Common bean under different water availability reveals classifiable stimuli-specific signatures in plant electrome

Plant electrophysiology has unveiled the involvement of electrical signals in the physiology and behavior of plants. Spontaneously generated bioelectric activity can be altered in response to changes in environmental conditions, suggesting that a plant's electrome may possess a distinct signature associated with various stimuli. Analyzing electrical signals, particularly the electrome, in conjunction with Machine Learning (ML) techniques has emerged as a promising approach to classify characteristic electrical signals corresponding to each stimulus. This study aimed to characterize the electrome of common bean (Phaseolus vulgaris L.) cv. BRS-Expedito, subjected to different water availabilities, seeking patterns linked to these stimuli. For this purpose, bean plants in the vegetative stage were subjected to the following treatments: (I) distilled water; (II) half-strength Hoagland's nutrient solution; (III) -2 MPa PEG solution; and (IV) -2 MPa NaCl solution. Electrical signals were recorded within a Faraday's cage using the MP36 electronic system for data acquisition. Concurrently, plant water status was assessed by monitoring leaf turgor variation. Leaf temperature was additionally measured. Various analyses were conducted on the electrical time series data, including arithmetic average of voltage variation, skewness, kurtosis, Probability Density Function (PDF), autocorrelation, Power Spectral Density (PSD), Approximate Entropy (ApEn), Fast Fourier Transform (FFT), and Multiscale Approximate Entropy (ApEn(s)). Statistical analyses were performed on leaf temperature, voltage variation, skewness, kurtosis, PDF µ exponent, autocorrelation, PSD β exponent, and approximate entropy data. Machine Learning analyses were applied to identify classifiable patterns in the electrical time series. Characterization of the electrome of BRS-Expedito beans revealed stimulus-dependent profiles, even when alterations in water availability stimuli were similar in terms of quality and intensity. Additionally, it was observed that the bean electrome exhibits high levels of complexity, which are altered by different stimuli, with more intense and aversive stimuli leading to drastic reductions in complexity levels. Notably, one of the significant findings was the 100% accuracy of Small Vector Machine in detecting salt stress using electrome data. Furthermore, the study highlighted alterations in the plant electrome under low water potential before observable leaf turgor changes. This work demonstrates the potential use of the electrome as a physiological indicator of the water status in bean plants.

A stable delivery system for curcumin: Fabrication and characterization of self-assembling acylated kidney bean protein isolate nanogels

The construction of protein-based nano-gels as curcumin delivery system effectively enhances the stability and bioavailability of curcumin. In this study, acylation modification and self-assembly techniques were jointly employed to construct acylated kidney bean protein isolate (AKBPI)-nanogels. Optimal conditions for AKBPI-nanogels were determined to be pH 7, concentration of 2 mg/mL, and temperature at 90℃ for 30 min. The optimized AKBPI-nanogels exhibited excellent uniformity as evidenced by decreasing average particle size (137.35 nm) and polydispersity index (0.38). Acylation enhanced the intermolecular interactions within the nanogel by reducing the polarity of tyrosine microenvironment and free sulfhydryl groups. AKBPI-nanogels demonstrated remarkable characteristics in terms of pH sensitivity, salt concentration, and storage tolerance. The curcumin-loaded AKBPI-nanogels exhibited an encapsulation efficiency of 92.30 % and maintained high antioxidant activity. In simulated gastrointestinal digestion, AKBPI-nanogels facilitated the controlled release and higher bioavailability of curcumin. Therefore, AKBPI-nanogels can be a stable tool for delivering curcumin.

Quantitative assessment of molecular, microstructural, and macroscopic changes of red kidney beans (Phaseolus vulgaris L.) during cooking provides detailed insights in their cooking behavior

Quantitative changes at different length scales (molecular, microscopic, and macroscopic levels) during cooking were evaluated to better understand the cooking behavior of common beans. The microstructural evolution of presoaked fresh and aged red kidney beans during cooking at 95 °C was quantified using light microscopy coupled with image analysis. These data were related to macroscopic properties, being hardness and volume changes representing texture and swelling of the beans during cooking. Microstructural properties included the cell area (Acell), the fraction of intercellular spaces (%Ais), and the fraction of starch area within the cells (%As/c), reflecting respectively cell expansion, cell separation, and starch swelling. A strong linear correlation between hardness and %Ais (r = -0.886, p = 0.07), along with a significant relative change in %Ais (∼5 times), suggests that softening is predominantly due to cell separation rather than cell expansion. Regarding volume changes, substantial cell expansion (Acell increased by ∼1.5 times) during the initial 30 min of cooking was greatly associated with the increase in the cotyledon volume, while the significance of cell separation became more prominent during the later stages of cooking. Furthermore, we found that the seed coat, rather than the cotyledon, played a major role in the swelling of whole beans, which became less pronounced after aging. The macroscopic properties did not correlate with %As/c. However, the evolution of %As/c conveyed information on the swelling of the starch granules during cooking. During the initial phase, the starch granule swelling mainly filled the cells, while during the later phase, the further swelling was confined by the cell wall. This study provides strong microscopic evidence supporting the direct involvement of the cell wall/ middle lamella network in microstructural changes during cooking as affected by aging, which is in line with the results of molecular changes.

A study of anti-wrinkle functions and improvement of cream with Phaseolus angularis

Chronic exposure to ultraviolet (UV) radiation from sunlight accelerates skin ageing, which is followed by harsh, thick, dry and loose conditions. One of the most demonstrative symptoms is deep wrinkles induced by skin barrier disruption. Our previous research showed that Phaseolus angularis seed extract (PASE) effectively inhibits skin ageing through UVB protection in HaCaT cells by suppressing skin damage. However, its efficacy has not been evaluated in clinical trials so far. PASE cream's effectiveness was initially tested on the artificial skin model, revealing an increase in filaggrin and defence against skin damage. Based on these results, in this single-centred, randomized, double-blind study, we investigated the anti-ageing effect of PASE in human eye wrinkle areas. For these 21 healthy adult women aged 30 to 59, a PASE cream was applied to the right eye wrinkle area and a placebo to the left eye wrinkle area twice a day (morning and evening) for 12 weeks. The change in thick, deep crease wrinkles around the eyes was confirmed by visual evaluation, skin measurements and a questionnaire. As a result, the surface roughness (R1), maximum roughness (R2), average roughness (R3), smoothness depth (R4) and arithmetic mean roughness (R5) values in the group using the PASE cream all decreased. Particularly, R1, R4 and R5 significantly decreased by 18.1%, 18.6% and 25.0%, respectively. Subjects who applied PASE cream also experienced an improvement in skin moisture nearly twice the time compared to the placebo group. In addition, no participants reported side effects. Our study showed that PASE cream led to clinically significant levels of wrinkle improvement. In conclusion, as PASE is a natural, safe food with no side effects, it can be a good resource for natural anti-wrinkle functional cosmetics in the future.

Genome-wide analysis of PvMADS in common bean and functional characterization of PvMADS31 in Arabidopsis thaliana as a player in abiotic stress responses

Changing climatic conditions with rising temperatures and altered precipitation patterns pose significant challenges to agricultural productivity, particularly for common bean crops. Transcription factors (TFs) are crucial regulators that can mitigate the impact of biotic and abiotic stresses on crop production. The MADS-box TFs family has been implicated in various plant physiological processes, including stress-responsive mechanisms. However, their role in common bean and their response to stressful conditions remain poorly understood. Here, we identified 35 MADS-box gene family members in common bean, with conserved MADS-box domains and other functional domains. Gene duplication events were observed, suggesting the significance of duplication in the evolutionary development of gene families. The analysis of promoter regions revealed diverse elements, including stress-responsive elements, indicating their potential involvement in stress responses. Notably, PvMADS31, a member of the PvMADS-box gene family, demonstrated rapid upregulation under various abiotic stress conditions, including NaCl, polyethylene glycol, drought, and abscisic acid (ABA) treatments. Transgenic plants overexpressing PvMADS31 displayed enhanced lateral root development, root elongation, and seed germination under stress conditions. Furthermore, PvMADS31 overexpression in Arabidopsis resulted in improved drought tolerance, likely attributed to the enhanced scavenging of ROS and increased proline accumulation. These findings suggest that PvMADS31 might play a crucial role in modulating seed germination, root development, and stress responses, potentially through its involvement in auxin and ABA signaling pathways. Overall, this study provides valuable insights into the potential roles of PvMADS-box genes in abiotic stress responses in common bean, offering prospects for crop improvement strategies to enhance resilience under changing environmental conditions.

Enzymatic activity and development of Frankliniella occidentalis (Thysanoptera: Thripidae) in response to exogenous calcium treatments of kidney bean plants

Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) is an agricultural pest threatening various horticultural crops worldwide. Inducing plant resistance is an ecologically beneficial and potentially effective method for controlling F. occidentalis. As an essential nutrient element, exogenous calcium enhances plant-induced resistance. This study investigated the effects of CaCl2 on the secondary metabolites of kidney bean plants and detoxifying and digestive enzymes in F. occidentalis. We found that treatment of plants and treatment time and also the interactions of the 2 factors significantly affected secondary metabolites contents (tannin, flavonoids, total phenol, alkaloid, and lignin) of kidney bean leaves, which indicated that that the effect of treatment of plants on secondary metabolites varied with treatment time. Moreover, when thrips fed on CaCl2-treated plants, the activities of detoxifying enzymes, enzymes glutathione S-transferase and cytochrome P450 substantially increased compared to those in which thrips fed on control plants. However, the activity of carboxylesterase significantly decreased. The detoxifying enzyme genes CL992.contig6, CYP4PN1, and CYP4PJ2 were significantly upregulated at 24 and 48 h. The activities of digestive enzymes (α-amylase, chymotrypsin, and lipase) increased substantially in F. occidentalis. The digestive enzyme gene, FoAMY-1, was significantly upregulated at 24 and 48 h after treatment. The pupation rate and pupal weight of F. occidentalis were significantly reduced. The results indicated that exogenous CaCl2-induced metabolic changes in kidney bean plants and altered the enzymatic activity and development of F. occidentalis that fed upon them.

Mapping pathogenic bacteria resistance against common antibiotics and their potential susceptibility to methylated white kidney bean protein

As antibiotics cannot inhibit multidrug-resistant bacteria (MDR), continuous research is mandatory to find other antibacterials from natural resources. Native legume proteins and their modified forms exhibited broad spectra of high antimicrobial activities. Sixteen bacterial isolates were mapped for antibiotic resistance, showing resistance in the range of (58-92%) and (42-92%) in the case of the Gram-negative and Gram-positive bacteria, respectively. White native Phaseolus vulgaris protein (NPP) was isolated from the seeds and methylated (MPP). The MIC range of MPP against 7 MDR bacteria was 10-25 times lower than NPP and could (1 MIC) considerably inhibit their 24 h liquid growth. MPP showed higher antibacterial effectiveness than Gentamycin, the most effective antibiotic against Gram-positive bacteria and the second most effective against Gram-negative bacteria. However, MPP recorded MICs against the seven studied MDR bacteria in the 1-20 µg/mL range, the same for Gentamycin. The combination of Gentamycin and MPP produced synergistic effects against the seven bacteria studied, as confirmed by the Transmission Electron Microscopic images. The antimicrobial activity of MPP against the seven MDR bacteria remained stable after two years of cold storage at 8-10 °C as contrasted to Gentamycin, which lost 20-72% of its antimicrobial effectiveness.

Lima bean (Phaseolus lunatus Linn.) protein isolate as a promising plant protein mixed with xanthan gum for stabilizing oil-in-water emulsions

BACKGROUND

Lima bean protein isolate (LPI) is an underutilized plant protein. Similar to other plant proteins, it may display poor emulsification properties. In order to improve its emulsifying properties, one effective approach is using protein and polysaccharide mixtures. This work investigated the structural and emulsifying properties of LPI as well as the development of an LPI/xanthan gum (XG)-stabilized oil-in-water emulsion.

RESULTS

The highest protein solubility (84.14%) of LPI was observed and the molecular weights (Mw ) of most LPI subunits were less than 35 kDa. The enhanced emulsifying activity index (15.97 m2  g-1 ) of LPI might be associated with its relatively high protein solubility and more low-Mw subunits (Mw  < 35 kDa). The effects of oil volume fraction (ϕ) on droplet size, microstructure, rheological behavior and stability of emulsions were investigated. As ϕ increased from 0.2 to 0.8, the emulsion was arranged from spherical and dispersed oil droplets to polyhedral packing of oil droplets adjacent to each other, while the LPI/XG mixtures changed from particles (in the uncrowded interfacial layer) to lamellae (in the crowded interfacial layer). When ϕ was 0.6, the emulsion was in a transitional state with the coexistence of particles and lamellar structures on the oil droplet surface. The LPI/XG-stabilized emulsions with ϕ values of 0.6-0.8 showed the highest stability during a 14-day storage period.

CONCLUSION

This study developed a promising plant-based protein resource, LPI, and demonstrates potential application of LPI/XG as an emulsifying stabilizer in foods. © 2023 Society of Chemical Industry.

Silicon via fertigation with and without potassium application, improve physiological aspects of common beans cultivated under three water regimes in field

Frequent droughts have led to an expansion of irrigated common bean (Phaseolus vulgaris L.) cultivation areas. An effective strategy to enhance water use efficiency and optimize crop growth is the application of silicon (Si) and potassium (K). However, the interaction between Si dosage, water regimes, and plant potassium status, as well as the underlying physiological mechanisms, remains unknown. This study aimed to assess the effects of Si doses applied via fertigation under various water regimes, in the presence and absence of potassium fertilization, on gas exchange, water use efficiency, and growth of Common beans in field conditions. Two experiments were conducted, one with and one without K supply, considering that the potassium content in the soil was 6.4 mmolc dm-3 in both experiments and a replacement dose of 50 kg ha was applied in the with K treatment, with the same treatments evaluated in both potassium conditions. The treatments comprised a 3 × 4 factorial design, encompassing three water regimes: 80% (no deficit), 60% (moderate water deficit), and 40% (severe water deficit) of soil water retention capacity, and four doses of Si supplied via fertigation: 0, 4, 8, and 12 kg ha-1. Where it was evaluated, content of photosynthetic pigments, fluorescence of photosynthesis, relative water content, leaf water potential and electrolyte extravasation, dry mass of leaves, stems and total. The optimal doses of Si for fertigation application, leading to increased Si absorption in plants, varied with decreasing soil water content. The respective values were 6.6, 7.0, and 7.1 kg ha-1 for the water regimes without deficit, with moderate water deficit, and with severe water deficit. Fertigation application of Si improved plant performance, particularly under severe water deficit, regardless of potassium status. This improvement was evident in relative water content, leaf water potential, and membrane resistance, directly impacting pigment content and gas exchange rates. The physiological effects resulted in enhanced photosynthesis in water-deficient plants, mitigating dry mass production losses. This research demonstrates, for the first time in common bean, the potential of Si to enhance irrigation efficiency in areas limited by low precipitation and water scarcity.

Genome-wide identification, characterization, and expression analysis of MIPS family genes in legume species

BACKGROUND

Evolutionarily conserved in plants, the enzyme D-myo-inositol-3-phosphate synthase (MIPS; EC 5.5.1.4) regulates the initial, rate-limiting reaction in the phytic acid biosynthetic pathway. They are reported to be transcriptional regulators involved in various physiological functions in the plants, growth, and biotic/abiotic stress responses. Even though the genomes of most legumes are fully sequenced and available, an all-inclusive study of the MIPS family members in legumes is still ongoing.

RESULTS

We found 24 MIPS genes in ten legumes: Arachis hypogea, Cicer arietinum, Cajanus cajan, Glycine max, Lablab purpureus, Medicago truncatula, Pisum sativum, Phaseolus vulgaris, Trifolium pratense and Vigna unguiculata. The total number of MIPS genes found in each species ranged from two to three. The MIPS genes were classified into five clades based on their evolutionary relationships with Arabidopsis genes. The structural patterns of intron/exon and the protein motifs that were conserved in each gene were highly group-specific. In legumes, MIPS genes were inconsistently distributed across their genomes. A comparison of genomes and gene sequences showed that this family was subjected to purifying selection and the gene expansion in MIPS family in legumes was mainly caused by segmental duplication. Through quantitative PCR, expression patterns of MIPS in response to various abiotic stresses, in the vegetative tissues of various legumes were studied. Expression pattern shows that MIPS genes control the development and differentiation of various organs, and have significant responses to salinity and drought stress.

CONCLUSION

The MIPS genes in the genomes of legumes have been identified, characterized and their expression was analysed. The findings pave way for understanding their molecular functions and evolution, and lead to identify the putative MIPS genes associated with different cell and tissue development.

Anti-Obesity Effect of Combining White Kidney Bean Extract, Propolis Ethanolic Extract and CrPi3 on Sprague-Dawley Rats Fed a High-Fat Diet

Obesity has been associated with the occurrence and prevalence of various chronic metabolic diseases. The management of obesity has evolved to focus not only on reducing weight, but also on preventing obesity-related complications. Studies have shown that bioactive components in natural products like white kidney bean extract (WKBE), propolis ethanolic extract (PEE), and chromium picolinate (CrPi3) showed anti-obesity properties. However, no studies have examined the outcomes of combining any of these nutraceutical supplements. We compared the effects of HFD supplemented with WKBE, WKBE+PEE, or WKBE+PEE+CrPi3 against control and obese groups using Sprague-Dawley rats fed a 45% high-fat diet as an in vivo model. Nutritional parameters, biochemical parameters, and biomarkers of cardiovascular disease, liver function, kidney function, and gut health were among the comparable effects. Our findings showed that combining the three nutraceutical supplements had a synergetic effect on reducing weight gain, food utilization rate, abdominal fat, serum lipids, arterial and hepatic lipids, risk of cardiovascular disease, and blood glucose level, in addition to improving renal function and gut microbiota. We attributed these effects to the α-amylase inhibitor action of WKBE, flavonoids, and polyphenol content of PEE, which were potentiated with CrPi3 resulting in a further reduction or normalization of certain parameters.

Silicon (Si) mitigates the negative effects of iron deficiency in common bean (Phaseolus vulgaris L.) by improving photosystem activities and nutritional status

Silicon (Si) is the second most abundant element in the Earth's crust after oxygen. Its beneficial impact on crop development and yield, particularly under stressful conditions such as iron (Fe) deficiency, has been well documented. Fe deficiency is a critical constraint that limits crop production globally. The objective of this study was to investigate the effects of silicon (Na2SiO3) on common bean (Phaseolus vulgaris L. 'Coco Rose' variety) under iron-deficient conditions. The common bean plants were subjected to six treatments, which included three sufficient iron treatments (50 μM Fe) each paired with three varying silicon concentrations (0, 0.25, and 0.5 mM Si), and three iron-deficient treatments (0.1 μM Fe) each associated with the same silicon concentrations (0, 0.25, and 0.5 mM Si). The results indicate that iron deficiency had a negative impact on almost all the measured parameters. However, under silicon treatments, especially with 0.5 mM Si, the depressive effects of iron deficiency were significantly mitigated. The addition of 0.5 mM Si alleviated leaf chlorosis and improved biomass production, nutritional status, photosynthetic pigment content, photosynthetic gas exchange, and photosystem (PSI and PSII) activities. Interestingly, a greater beneficial effect of silicon was observed on PSII compared to PSI. This was accompanied by a significant augmentation in leaf iron concentration by 42%. Therefore, by enhancing the photosystem activities and nutritional status, among other mechanisms, silicon is capable of mitigating the adverse effects of iron-deficient conditions, making it a successful and effective solution to cope with this nutritional stress.

Antiproliferative and anti-inflammatory effects of fractionated crude lectins from boiled kidney beans (Phaseolus vulgaris)

In this study, we investigated the biological profile of lectins isolated from raw and boiled Japanese red Kintoki beans (red kidney beans [RKB]; Phaseolus vulgaris). Lectins in beans showing agglutination activity were retained after heating. Raw and boiled RKB lectins were fractionated using carboxymethyl- and diethylaminoethyl-Sepharose, respectively. Boiled RKB lectins were evaluated for carbohydrate specificity as well as cytokine-inducing and antiproliferative activities against cancer cells and compared with raw RKB lectins. Raw RKB lectins showed specificity for thyroglobulin and fetuin, whereas boiled lectins showed specificity for N-acetylneuraminic acid. Raw RKB lectins showed low resistance to proteases and tolerated temperatures greater than 80°C for 5 min. Notably, lectins from raw and boiled beans showed antiproliferative activity against five types of cancer cells B16, LM8, HeLa, HepG2, and Colo 679. In particular, lectins from raw beans exhibited a significantly stronger activity than those from boiled beans. Anti-inflammatory effects were notably observed in crude extracts from raw and boiled beans. Specifically, lectins fractionated from boiled beans markedly inhibited the expression of tumor necrosis factor-α and interleukin-6. Overall, our results showed that RKB lectins from boiled beans exert anti-inflammatory and anticancer effects and could be developed as potential chemopreventive agents. PRACTICAL APPLICATION: Japanese red kidney beans (RKB) are cultivated in numerous parts of the temperate zone and consumed in many countries. Lectins from boiled beans exhibited anticancer activity, similar to lectins from raw beans. Additionally, crude and fractionated lectins from boiled beans showed anti-inflammatory activity. Thus, boiled RKB lectins have the potential to be used as a bioactive protein for medical research and could be developed as anticancer agents.

Impact of red kidney bean protein on starch digestion and exploring its underlying mechanism

This study aimed to investigate the effect of different proportions of red kidney bean protein (RKP) on the digestibility of co-gelatinized wheat starch (WS) and corn starch (CS), as well as explore the potential underlying mechanisms. The results showed a significant reduction in both the rate and extent of digestion for WS and CS after adding the RKP during co-gelatinization. Furthermore, incorporating RKP at 0 % to 20 % levels increased the content of resistant starch (RS) by 34.89 % and 14.43 % in the digested systems of wheat starch and maize starch, respectively, while decreasing the concentration of rapidly digestible starch (RDS) by 12.24 % and 20.39 %, respectively. Furthermore, RKP was found to inhibit α-amylase in a dose-dependent and non-competitive manner. Its interaction with starch occurred through hydrogen bonds and hydrophobic interactions, resulting in a modification of the short-range ordered structure of starch and ultimately leading to inhibition of starch digestion. The physical barrier effect of RKP on starch digestion also contributed to its inhibitory action. Considering the health-related delay in the rate and extent of postprandial starch digestion, Our findings have important inspirational value for the use of red kidney bean protein in hypoglycemic foods.

Negro Jamapa) on glucose metabolism and oxidative stress in induced diabetic lab rats model

A retrograded starch ingredient obtained from Negro Jampa beans (Phaseolus vulgaris L. Negro Jamapa), applying a debranching process (18 U/g for 12 h) and retrogradation (2 °C for 3 days), was evaluated as a potential functional ingredient to improve glucose homeostasis in a diabetic animal model. The obtained ingredient was reduced in rapid digestible starch amount compared to its related isolated native starch (34.1 % and 53.6 %, respectively) and resistant (33.4 % and 22.3 %, respectively). Therefore, a reduced total digestibility was determined for the obtained ingredient compared to native starch (51.5 % and 79 %, respectively). As consequence, diabetic animals fed with functional ingredient replacement (30 %) showed a lower and attenuated postprandial glucose levels, reducing the hyperglycaemic condition, compared with the non-treated animals (r2 = 0.9775; p ≤ 0.05), reducing the glucose serum levels 73 % compared (17.21 vs 23.6 mmol/L, respectively). Also, significant improvement on weight gain (49.75 ± 34.1 g) compared to non-treated (18.14 ± 45.52 g), as well as lower insulin resistance index and improved oxidative stress status was determined for the treated group. These results highlight the potential of retrograded starch obtained from Negro Jamapa beans as a functional ingredient focus on the improvement of the glucose homeostasis and diabetic condition.

Role of a LORELEI- like gene from Phaseolus vulgaris during a mutualistic interaction with Rhizobium tropici

Reactive oxygen species (ROS), produced by NADPH oxidases known as RBOHs in plants, play a key role in plant development, biotic and abiotic stress responses, hormone signaling, and reproduction. Among the subfamily of receptor-like kinases referred to as CrRLK, there is FERONIA (FER), a regulator of RBOHs, and FER requires a GPI-modified membrane protein produced by LORELEI (LRE) or LORELEI-like proteins (LLG) to reach the plasma membrane and generate ROS. In Arabidopsis, AtLLG1 is involved in interactions with microbes as AtLLG1 interacts with the flagellin receptor (FLS2) to trigger the innate immune response, but the role of LLGs in mutualistic interactions has not been examined. In this study, two Phaseolus vulgaris LLG genes were identified, PvLLG2 that was expressed in floral tissue and PvLLG1 that was expressed in vegetative tissue. Transcripts of PvLLG1 increased during rhizobial nodule formation peaking during the early period of well-developed nodules. Also, P. vulgaris roots expressing pPvLLG1:GFP-GUS showed that this promoter was highly active during rhizobium infections, and very similar to the subcellular localization using a construct pLLG1::PvLLG1-Neon. Compared to control plants, PvLLG1 silenced plants had less superoxide (O2-) at the root tip and elongation zone, spotty hydrogen peroxide (H2O2) in the elongation root zone, and significantly reduced root hair length, nodule number and nitrogen fixation. Unlike control plants, PvLLG1 overexpressing plants showed superoxide beyond the nodule meristem, and significantly increased nodule number and nodule diameter. PvLLG1 appears to play a key role during this mutualistic interaction, possibly due to the regulation of the production and distribution of ROS in roots.

Chemometric Evaluation of RI-Induced Phytochemicals in Phaseolus vulgaris Seeds Indicate an Improvement on Liver Enzymes in Obese Rats

Liver enzymes alterations (activity or quantity increase) have been recognized as biomarkers of obesity-related abnormal liver function. The intake of healthy foods can improve the activity of enzymes like aspartate and alanine aminotransferases (AST, ALT), γ-glutaminyl transferase (GGT), and alkaline phosphatase (ALP). Beans have a high concentration of several phytochemicals; however, Restriction Irrigation (RI) during plant development amends their synthesis. Using chemometric tools, we evaluated the capacity of RI-induced phytochemicals to ameliorate the high activity of liver enzymes in obese rats. The rats were induced with a high-fat diet for 4 months, subsequently fed with 20% cooked beans from well-watered plants (100/100), or from plants subjected to RI at the vegetative or reproduction stage (50/100, 100/50), or during the whole cycle (50/50) for 3 months. A partial least square discriminant analysis indicated that mostly flavonols have a significant association with serum AST and ALT activity, while isoflavones lowered GGT and ALP. For AST and ALT activity in the liver, saponins remained significant for hepatocellular protection and flavonoids remained significant as hepatobiliary protectants by lowering GGT and ALP. A principal component analysis demonstrated that several flavonoids differentiated 100/50 treatment from the rest, while some saponins were correlated to 50/100 and 50/50 treatments. The intake of beans cultivated under RI improves obesity-impaired liver alterations.

Phenolic Composition, Antioxidant Capacity, and α-Glucosidase Inhibition of Boiled Green Beans and Leaves from Chilean Phaseolus vulgaris

The tender green pods of the common bean (Phaseolus vulgaris L.) are marketed fresh, frozen or canned. The main bean accessions cultivated for green pods in central Chile are Arroz, Magnum, Peumo and the introduced Malibú. Little is known about the identity of phenolics in the processed pods or in the boiled bean leaves. Raw leaves from Chilean bean landraces showed a strong inhibition towards the enzyme α-glucosidase, associated with flavonoids and caffeoyl malic acid content. The aim of this work was to assess the phenolic composition, antioxidant capacity and activity towards α-glucosidase of boiled leaves and green pods from selected bean landraces. The study was performed with four green pods samples and six leaf accessions, respectively. The leaves included the continuous growth bean Ñuño (red seed and black seed). Antioxidant capacity and inhibition of α-glucosidase were measured. The main phenolics were identified by comparison with standards and were quantified using calibration curves. The extracts of most boiled green pods inhibited α-glucosidase while the leaves were inactive. The content of phenolics in the boiled pods is low, with rutin and quercetin 3-O-glucuronide as the main constituents. In boiled leaves, the main phenolics were quercetin 3-O-glucuronide and kaempferol 3-O-glucuronide. The main flavonoids and caffeoyl malic acid in leaves decreased after boiling. Boiling affected the phenolic profile, reducing antioxidant capacity and glucosidase inhibition, highlighting the importance of characterizing foods as they are ingested.

from Lake Magadi, Kenya, against Rhizoctonia solani Kühn in Phaseolus vulgaris L

A decline in common bean production and the ineffectiveness of synthetic chemical products in managing plant pathogens has led to exploiting Kenyan soda lakes as an alternative search for biocontrol agents. This study aimed to identify phylogenetically Bacillus spp. from Lake Magadi and their antagonistic activity against Rhizoctonia solani under in vitro and in vivo conditions. The 16 S ribosomal RNA (rRNA) subunit sequences of six bacterial strains isolated from Lake Magadi showed diversity similar to the Bacillus genus; Bacillus velezensis, Bacillus subtilis, and Bacillus pumilus. In vitro, antagonism showed varied mycelium inhibition rates of fungi in the coculture method. Enzymatic assays showed the varied ability of isolates to produce phosphatase, pectinase, chitinase, protease, indole-3-acetic acid (IAA), and hydrogen cyanide (HCD). The in vivo assay showed M09 (B. velezensis) with the lowest root mortality and incidence of postemergence wilt. Pre-emergence wilt incidence was recorded as lowest in M10 (B. subtilis). Isolate M10 had the highest phenylalanine ammonia-lyase (PAL) for defense enzymes, while polyphenol oxidase (PPO) and peroxidase were recorded as highest in M09. For the phenolic content, M10 recorded the highest phenolic content. In conclusion, Lake Magadi harbors Bacillus spp, which can be used as a potential biocontrol of R. solani.

nov., a biological control bacterium isolated from the common bean (Phaseolus vulgaris L.) crop in Sinaloa, Mexico

Strain FSQ1T was isolated from the rhizosphere of the common bean (Phaseolus vulgaris L.) crop sampled in a commercial field located in the Gabriel Leyva Solano community, which belongs to the Guasave municipality (state of Sinaloa, Mexico). Based on its full-length 16S rRNA gene sequence, strain FSQ1T was assigned to the genus Bacillus (100 % similarity). This taxonomic affiliation was supported by its morphological and metabolic traits. Strain FSQ1T was a Gram-stain-positive bacterium with the following characteristics: rod-shaped cells, strictly aerobic, spore forming, catalase positive, reduced nitrate to nitrite, hydrolysed starch and casein, grew in the presence of lysozyme and 2 % NaCl, utilized citrate, grew at pH 6.0-8.0, produced acid from glucose, was unable to produce indoles from tryptophan, and presented biological control against Sclerotinia sclerotiorum. The whole-genome phylogenetic results showed that strain FSQ1T formed an individual clade in comparison with highly related Bacillus species. In addition, the maximum values for average nucleotide identity and from Genome-to-Genome Distance Calculator analysis were 91.57 and 44.20 %, respectively, with Bacillus spizizenii TU-B-10T. Analysis of its fatty acid content showed the ability of strain FSQ1T to produce fatty acids that are not present in closely related Bacillus species, such as C18 : 0 and C20 : 0. Thus, these results provide strong evidence that strain FSQ1T represents a novel species of the genus Bacillus, for which the name Bacillus mexicanus sp. nov. is proposed. The type strain is FSQ1T (CM-CNRG TB51T=LBPCV FSQ1T).

A comprehensive metabolomics and lipidomics atlas for the legumes common bean, chickpea, lentil and lupin

Legumes represent an important component of human and livestock diets; they are rich in macro- and micronutrients such as proteins, dietary fibers and polyunsaturated fatty acids. Whilst several health-promoting and anti-nutritional properties have been associated with grain content, in-depth metabolomics characterization of major legume species remains elusive. In this article, we used both gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) to assess the metabolic diversity in the five legume species commonly grown in Europe, including common bean (Phaseolus vulgaris), chickpea (Cicer arietinum), lentil (Lens culinaris), white lupin (Lupinus albus) and pearl lupin (Lupinus mutabilis), at the tissue level. We were able to detect and quantify over 3400 metabolites covering major nutritional and anti-nutritional compounds. Specifically, the metabolomics atlas includes 224 derivatized metabolites, 2283 specialized metabolites and 923 lipids. The data generated here will serve the community as a basis for future integration to metabolomics-assisted crop breeding and facilitate metabolite-based genome-wide association studies to dissect the genetic and biochemical bases of metabolism in legume species.

Effects of processing technologies on the antioxidant properties of common bean (Phaseolus vulgaris L.) and lentil (Lens culinaris) proteins and their hydrolysates

The effects of ultrasound (280 W, 5 min), heat treatment (75 °C and 90 °C for 10 min) and microfluidization (125 MPa, 4 cycles) as pre or post treatments and their combination with enzymatic hydrolysis on the antioxidant properties of common bean and lentil protein hydrolysates were investigated. In general, hydrolysis resulted in increases of antioxidant activity, both in the presence and absence of processing technologies. The increases reached maximum values of 158% (ABTS), 105% (DPPH), 279% (FRAP) and 107% (TAC) for the bean protein hydrolysates submitted to post-treatment with ultrasound (ABTS, FRAP and TAC) and pre-treatment with microfluidization (DPPH), compared to their respective controls (untreated samples). For lentil proteins, the increases reached 197% (ABTS), 170% (DPPH), 690% (FRAP) and 213% (TAC) for samples submitted to ultrasound post-treatment (ABTS), microfluidization pre-treatment (DPPH) and post-treatment (FRAP), and 75 °C pre-treatment (TAC) compared to their respective controls. Surface hydrophobicity and molecular weight profile by SEC-HPLC analysis indicated modifications in the structures of proteins in function of the different processing technologies. For both proteins, electrophoresis indicated a similar profile for all hydrolysates, regardless of the process applied as pre or post treatment. Solubility of bean and lentil protein concentrates was also improved. These results indicated that different processing technologies can be successfully used in association with enzymatic hydrolysis to improve the antioxidant properties of lentil and bean proteins.

Exploring the nutritional and health benefits of pulses from the Indian Himalayan region: A glimpse into the region's rich agricultural heritage

Pulses have been consumed worldwide for over 10 centuries and are currently among the most widely used foods. They are not economically important, but also nutritionally beneficial as they constitute a good source of protein, fibre, vitamins and minerals such as iron, zinc, folate and magnesium. Pulses, but particularly species such as Macrotyloma uniflorum, Phaseolus vulgaris L., Glycine max L. and Vigna umbellate, are essential ingredients of the local diet in the Indian Himalayan Region (IHR). Consuming pulses can have a favourable effect on cardiovascular health as they improve serum lipid profiles, reduce blood pressure, decrease platelet activity, regulate blood glucose and insulin levels, and reduce inflammation. Although pulses also contain anti-nutritional compounds such as phytates, lectins or enzyme inhibitors, their deleterious effects can be lessened by using effective processing and cooking methods. Despite their great potential, however, the use of some pulses is confined to IHR regions. This comprehensive review discusses the state of the art in available knowledge about various types of pulses grown in IHR in terms of chemical and nutritional properties, health effects, accessibility, and agricultural productivity.

durum) and white bean (Phaseolus vulgaris L.) seed germination

This research was undertaken to optimize the phenolic compound removal from Olive Mill Wastewater (OMW) by sawdust and red clay as natural adsorbents. Fractional factorial experimental design at 25-1 was used in order to optimize the experimental conditions for high removal efficiency. Statistics ANOVA analysis, Fisher's test, and Student's test suggested that the adsorbent dose has the most significant influence on polyphenol removal for both adsorbents. The maximum removal of polyphenols by sawdust reached 49.6% at 60 °C by using 60 g/L of adsorbent dose, pH 2, reaction time of 24 h, and agitation speed of 80 rpm. Whereas, for red clay, 48.08% of polyphenols removal was observed under the same conditions for sawdust except the temperature of 25 °C instead of 60 °C. In addition, the thermodynamic parameters suggested spontaneous process for both adsorbents, endothermic for the sawdust and exothermic for red clay. Furthermore, the phytotoxicity effect of OMW on durum wheat (Triticum turgidum L. var. durum) and white bean (Phaseolus vulgaris L.) seed germination was investigated. The obtained results showed that the untreated OMW inhibited the seed germination of T. turgidum and P. vulgaris seeds. OMW treatment with red clay followed by dilution (95% water) resulted in 87 and 30% germination of P. vulgaris and T. turgidum, respectively. While, the treatment of OMW with sawdust and dilution at 95% resulted in 51 and 26% germination of P. vulgaris and T. turgidum, respectively.

Investigating the interactions of endornaviruses with each other and with other viruses in common bean, Phaseolus vulgaris

BACKGROUND

Plant viruses of the genus Alphaendornavirus are transmitted solely via seed and pollen and generally cause no apparent disease. It has been conjectured that certain plant endornaviruses may confer advantages on their hosts through improved performance (e.g., seed yield) or resilience to abiotic or biotic insult. We recently characterised nine common bean (Phaseolus vulgaris L.) varieties that harboured either Phaseolus vulgaris endornavirus (PvEV1) alone, or PvEV1 in combination with PvEV2 or PvEV1 in combination with PvEV2 and PvEV3. Here, we investigated the interactions of these endornaviruses with each other, and with three infectious pathogenic viruses: cucumber mosaic virus (CMV), bean common mosaic virus (BCMV), and bean common mosaic necrosis virus (BCMNV).

RESULTS

In lines harbouring PvEV1, PvEV1 and PvEV2, or PvEV1, PvEV2 plus PvEV3, the levels of PvEV1 and PvEV3 RNA were very similar between lines, although there were variations in PvEV2 RNA accumulation. In plants inoculated with infectious viruses, CMV, BCMV and BCMNV levels varied between lines, but this was most likely due to host genotype differences rather than to the presence or absence of endornaviruses. We tested the effects of endornaviruses on seed production and seedborne transmission of infectious pathogenic viruses but found no consistent relationship between the presence of endornaviruses and seed yield or protection from seedborne transmission of infectious pathogenic viruses.

CONCLUSIONS

It was concluded that endornaviruses do not interfere with each other's accumulation. There appears to be no direct synergy or competition between infectious pathogenic viruses and endornaviruses, however, the effects of host genotype may obscure interactions between endornaviruses and infectious viruses. There is no consistent effect of endornaviruses on seed yield or susceptibility to seedborne transmission of other viruses.

The outstanding diversity of rhizobia microsymbionts of common bean (Phaseolus vulgaris L.) in Mato Grosso do Sul, central-western Brazil, revealing new Rhizobium species

Common bean is considered a legume of great socioeconomic importance, capable of establishing symbioses with a wide variety of rhizobial species. However, the legume has also been recognized for its low efficiency in fixing atmospheric nitrogen. Brazil is a hotspot of biodiversity, and in a previous study, we identified 13 strains isolated from common bean (Phaseolus vulgaris) nodules in three biomes of Mato Grosso do Sul state, central-western Brazil, that might represent new phylogenetic groups, deserving further polyphasic characterization. The phylogenetic tree of the 16S rRNA gene split the 13 strains into two large clades, seven in the R. etli and six in the R. tropici clade. The MLSA with four housekeeping genes (glnII, gyrB, recA, and rpoA) confirmed the phylogenetic allocation. Genomic comparisons indicated eight strains in five putative new species and the remaining five as R. phaseoli. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) comparing the putative new species and the closest neighbors ranged from 81.84 to 92.50% and 24.0 to 50.7%, respectively. Other phenotypic, genotypic, and symbiotic features were evaluated. Interestingly, some strains of both R. etli and R. tropici clades lost their nodulation capacity. The data support the description of the new species Rhizobium cerradonense sp. nov. (CNPSo 3464T), Rhizobium atlanticum sp. nov. (CNPSo 3490T), Rhizobium aureum sp. nov. (CNPSo 3968T), Rhizobium pantanalense sp. nov. (CNPSo 4039T), and Rhizobium centroccidentale sp. nov. (CNPSo 4062T).

5-ALA Improves the Low Temperature Tolerance of Common Bean Seedlings through a Combination of Hormone Transduction Pathways and Chlorophyll Metabolism

Low-temperature stress is a key factor limiting the yield and quality of the common bean. 5-aminolevulinic acid (5-ALA), an antioxidant in plants, has been shown to modulate plant cold stress responses. However, the molecular mechanisms of 5-ALA-induced physiological and chemical changes in common bean seedlings under cold stress remains unknown. This study explored the physiological and transcriptome changes of common bean seedlings in response to cold stress after 5-ALA pretreatment. Physiological results showed that exogenous 5-ALA promotes the growth of common bean plants under cold stress, increases the activity of antioxidant enzymes (superoxide dismutase: 23.8%; peroxidase: 10.71%; catalase: 9.09%) and proline content (24.24%), decreases the relative conductivity (23.83%), malondialdehyde (33.65%), and active oxygen content, and alleviates the damage caused by cold to common bean seedlings. Transcriptome analysis revealed that 214 differentially expressed genes (DEGs) participate in response to cold stress. The DEGs are mainly concentrated in indole alkaloid biosynthesis, carotenoid biosynthesis, porphyrin, and chlorophyll metabolism. It is evident that exogenous 5-ALA alters the expression of genes associated with porphyrin and chlorophyll metabolism, as well as the plant hormone signal transduction pathway, which helps to maintain the energy supply and metabolic homeostasis under low-temperature stress. The results reveal the effect that applying exogenous 5-ALA has on the cold tolerance of the common bean and the molecular mechanism of its response to cold tolerance, which provides a theoretical basis for exploring and improving plant tolerance to low temperatures.

Characteristics of the microstructure and the key components of white kidney bean sourdough bread induced by mixed-strain fermentation and its influence on gut microbiota

In this study, the effect of mixed-strain fermentation using Kluyveromyces marxianus with either Lactobacillus plantarum or Pediococcus pentosaceus on the physiochemical and nutritional properties of white kidney bean flour sourdough was investigated. The results indicated that mixed-strain fermentation reduced the anti-nutritional factors produced from the white kidney bean flour, especially in the sourdough fermented by L. plantarum and K. marxianus (WKS-LK) compared to that by P. pentosaceus and K. marxianus (WKS-JK). Meanwhile, the content of lactic acid and acetic acid and the proportion of peptides with molecular weights ranging from <500 to 5000 Da were increased in the sourdoughs (WKS-LK > WKS-JK). Compared to the control (WK), microstructural characteristics of the dough seemed to be improved in WKS-LK followed by WKS-JK in terms of their corresponding gluten network consistency. Moreover, mixed fermentation led to a reduced starch digestibility accompanied by a higher content of resistant starch and slowly digestible starch. In contrast, protein digestibility was enhanced in WKS-LK and WKS-JK sourdough breads. More importantly, the changes in gut microbiota composition, short-chain fatty acid (SCFA) production, systemic inflammation, glucose tolerance and liver tissue histopathology following 21-day consumption of the sourdough bread were also evaluated via an animal model. The intake of sourdough breads reduced the abundance of the pathogenic microbiota Escherichia shigella. In contrast, the corresponding abundance of Rikenellaceae, Akkermansiaceae, Erysipelotrichaceae, Prevotellaceae and Eubacterium coprostanoligenes was increased, followed by enhanced SCFA generation, with the highest in WKS-LK and then WKS-JK. Meanwhile, a reduced level of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α in the serum and improved glucose tolerance and liver tissue histopathology following the bread consumption were also achieved in the order of WKS-LK, then WKS-JK mice compared to WK.

Selection Behavior and OBP-Transcription Response of Western Flower Thrips, Frankliniella occidentalis, to Six Plant VOCs from Kidney Beans

Plant volatile organic compounds (VOCs) are an important link that mediates chemical communication between plants and plants, plants and insects, and plants and natural enemies of insect pests. In this study, we tested the response in the selective behavior of western flower thrips, Frankliniella occidentalis, to the VOCs of kidney bean, Phaseolus vulgaris L., to explore their "attraction" or "repellent" effects regarding their application in integrated pest management (i.e., IPM). The results indicated that 12.7 μL/mL (E, E, E, E)-squalene, 3.2 μL/mL dioctyl phthalate, and 82.2 μL/mL ethyl benzene had a significantly attractive effect on the selective behavior of F. occidentalis, while 10.7 μL/mL and 21.4 μL/mL 2,6-ditert-butyl-4-methyl phenol had a significantly repulsive effect on the selective behavior of F. occidentalis, showing that F. occidentalis responds differently to specific concentrations of VOCs from P. vulgaris plant emissions. Interestingly, the three compounds with the specific above concentrations, after being mixed in pairs, significantly attracted F. occidentalis compared to the control treatment; however, the mixture with the three above compounds had no significant different effect on F. occidentalis compared to the control treatment. It can be seen that the effect with the mixtures of three kinds of VOCs had the same function and may not get better. Simultaneously, the reasons for this result from the transcription levels of odorant-binding protein genes (OBPs) were determined. There were differences in the types and transcription levels of OBPs, which played a major role in the host selection behavior of F. occidentalis under the mixed treatment of different VOCs. It is presumed that there are specific VOCs from P. vulgaris plants that have a good repellent or attracting effect on the selective behavior of F. occidentalis, which can be used for the development of plant-derived insect attractants and repellents to serve as IPM in fields. But attention should be paid to the antagonism between plant-derived preparations and VOCs produced by plants themselves after application.

Spirulina platensis extract improves the production and defenses of the common bean grown in a heavy metals-contaminated saline soil

Plants have to cope with several abiotic stresses, including salinity and heavy metals (HMs). Under these stresses, several extracts have been used as effective natural biostimulants, however, the use of Spirulina platensis (SP) extract (SPE) remains elusive. The effects of SPE were evaluated as soil addition (SA) and/or foliar spraying (FS) on antioxidant defenses and HMs content of common bean grown in saline soil contaminated with HMs. Individual (40 or 80 mg SPE/hill added as SA or 20 or 40 mg SPE/plant added as FS) or integrative (SA+FS) applications of SPE showed significant improvements in the following order: SA-80+FS-40 > SA-80+FS-20 > SA-40+FS-40 > SA-40+FS-20 > SA-80 > SA-40 > FS-40 > FS-20 > control. Therefore, the integrative SA+FS with 40 mg SP/plant was the most effective treatment in increasing plant growth and production, overcoming stress effects and minimizing contamination of the edible part. It significantly increased plant growth (74%-185%) and yield (107%-227%) by enhancing net photosynthetic rate (78.5%), stomatal conductance (104%), transpiration rate (124%), and contents of carotenoids (60.0%), chlorophylls (49%-51%), and NPK (271%-366%). These results were concurrent with the marked reductions in malondialdehyde (61.6%), hydrogen peroxide (42.2%), nickel (91%-94%), lead (80%-9%), and cadmium (74%-91%) contents due to the improved contents of glutathione (87.1%), ascorbate (37.0%), and α-tocopherol (77.2%), and the activities of catalase (18.1%), ascorbate peroxidase (18.3%), superoxide dismutase (192%), and glutathione reductase (52.2%) as reinforcing mechanisms. Therefore, this most effective treatment is recommended to mitigate the stress effects of salinity and HMs on common bean production while minimizing HMs in the edible part.

Intrinsic labelling of common beans with 2H2O to enable estimates of protein digestibility

BACKGROUND

The use of plant protein intrinsically labelled with stable isotopes provides an innovative solution to assess the efficiency of protein intake by humans. Here, the incorporation of 2H has been applied to intrinsically labelled plant protein in the common bean. This study aimed to evaluate which is the best phenological phase of seed maturation to incorporate the heavy hydrogen isotope 2H into seed amino acids. Common beans (Phaseolus vulgaris L.) were grown in pots, then, after 50 days sowing, 2H2O dissolved in irrigation water was applied, then again at an interval of either 3, 6, 9, and 12 days.

RESULTS

Applications of 2H2O at 6, 9, and 12 days after the first application, in the full-flowering stage, were the best treatments for enriching protein-bound amino acids in the bean seed with 2H.

CONCLUSION

All treatments resulted in enrichment above 500 ppm, so the treatments (quantity and timing of 2H2O addition) were deemed successful for enriching bean seeds. This makes the intrinsically labelled seeds suitable for preparing test meals to assess the digestion and essential amino acid absorption of common bean amino acids in human subjects.

Genome-wide characterization and comparative analysis of the OSCA gene family and identification of its potential stress-responsive members in legumes

Cicer arietinum, Cajanus cajan, Vigna radiata, and Phaseolus vulgaris are economically important legume crops with high nutritional value. They are negatively impacted globally by different biotic and abiotic stresses. Hyperosmolality-gated calcium-permeable channels (OSCA) have been characterized as osmosensors in Arabidopsis thaliana but have not previously reported in legumes. This study provides a genome-wide identification, characterization, and comparative analysis of OSCA genes in legumes. Our study identified and characterized 13 OSCA genes in C. cajan, V. radiata, P. vulgaris, and 12 in C. arietinum, classified into four distinct clades. We found evidence to suggest that the OSCAs might be involved in the interaction between hormone signalling pathways and stress signalling pathways. Furthermore, they play a major role in plant growth and development. The expression levels of the OSCAs vary under different stress conditions in a tissue-specific manner. Our study can be used to develop a detailed understanding of stress regulatory mechanisms of the OSCA gene family in legumes.

Sustainable production of biopesticides for common bean root rot control within the biorefinery approach: a Technology Readiness Level 3 experimental proof of concept

Biopesticides are recognized as an efficient alternative to synthetic pesticides for pest and disease crop management. However, their commercial production processes use grains, generating large amounts of organic waste, even when agriculture waste or byproducts are the feedstock of choice. Frequently, these organic wastes are rich in nutrients that, after adequate treatment, can be used as nitrogen and carbohydrate sources for secondary metabolite production produced by microorganisms during submerged fermentation. In this sense, this study aimed to prove the concept that biopesticides could be produced under a full biorefinery process, using the entire biomass of an underexplored agroindustrial waste-damaged bean-as the main feedstock. A combination of sequential processes, including solid state fermentation, hydrolysis, and submerged fermentation, were designed for the production of two biopesticides (conventional-fungal conidia and second-generation secondary metabolite-cerulenin) from a high potential biological control agent strain Sarocladium oryzae BRM 59907. The combined processes, using damaged common bean grain as the main feedstock, provided biopesticides and organic fertilizer production that successfully controlled common bean root rot disease. This work proved to be possible the biopesticide production using a full biorefinery concept, inside the same productive chain, contributing to a sustainable environment and economy, together with animal and human health safety.

Natural Occurrence and Analysis of Nosema sp. Infection in the Adult Population of Western Bean Cutworm in Michigan

An understanding of population dynamics and insect biology is important for effective crop management strategies. Biotic factors such as pathogens play a large role on the fitness and dynamics of insect populations. Microsporidia are obligate intracellular parasites that infect more than 150 insect species and range from sublethal and chronic to fast acting and deadly. The western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a pest of both corn (Zea maize L. [Poales: Poaceae]) and dry beans (Phaseolus sp L. [Fabales: Fabaceae]) that is infected by a microsporidian parasite from the genus Nosema (Microsporidia: Nosematidae). Unfortunately, little is known about the interactions between the Nosema sp. (Microsporidia: Nosematidae) infecting the western bean cutworm and its prevalence and effects on the host population. This is especially true for the western bean cutworm population that has settled in the Great Lakes region over the last two decades. Using field caught samples and phase contrast microscopy, no consistent trends in pathogen load were observed over the course of the western bean cutworm flight season. A weak, but statistically significant relationship was observed between male body weight and pathogen load. Overall, we found a 100% prevalence of infection in the adult western bean cutworm population in Michigan.

Sustainable agricultural use of sewage sludge: impacts of high Zn concentration on on Folsomia candida, Enchytraeus crypticus, Lactuca sativa, and Phaseolus vulgaris

Zinc (Zn) is an essential micronutrient for plants and an important component for maintaining soil quality. Commonly found in the soil due to anthropogenic activities, such as industrialization and application of organic waste as fertilizers, in high concentrations, Zn may induce soil toxicity, affecting important communities, such as edaphic fauna. Despite its high concentrations found in the environment, Zn bioavailability can be affected by the type of soil, organic matter content and pH. In this work, Zn had its toxicity evaluated in a natural tropical soil, sampled in São Paulo-Brazil, for two soil invertebrates (Folsomia candida, Enchytraeus crypticus) and two seeds (Lactuca sativa and Phaseolus vulgaris), through ecotoxicological tests. The invertebrate E. crypticus was exposed to Zn concentrations of 10.0 (T1); 100.0 (T2); 150.0 (T3); 200.0 (T4); 400.0 (T5) mg Zn kg-1 of dry soil, while F. candida, L. sativa and P. vulgaris were exposed to Zn concentrations of 100.0; 200.0; 400.0; 800.0 (t6); 1600.0 (t7); and 2000.0 (t8) mg Zn kg-1 of dry soil. The outcome evaluated were seed germination, for L. sativa and P. vulgaris, and reproduction, for F. candida and E. crypticus. The EC50 obtained for E. crypticus, F. candida, L. sativa, and P. vulgaris were 261.5, 1089.7, 898.5, and 954.5 mg Zn kg-1 of dry soil, respectively, being E. crypticus the most sensitive organism, and only at the highest Zn's concentrations the organisms' reproduction and seeds' germination showed a statistically significant inhibitory effect (p < 0.05). Therefore, this work's results showed that Zn does not present significant toxicity for the tested soil organisms and seeds and that at 100 mg Zn kg-1 of dry soil it can be beneficial to F. candida and E. crypticus' reproduction and L. sativa's germination. These results imply that the presence of Zn in low concentrations, both in soil and biofertilizers, such as sewage sludge, not only is not a concern, but it can even benefit certain crops and functions of edaphic organisms, which may contribute to the engagement of sustainable agricultural practices and the quest for food security.

Transcriptome Dynamics of Common Bean Roots Exposed to Various Heavy Metals Reveal Valuable Target Genes and Promoters for Genetic Engineering

Understanding the gene regulatory basis of plant response to heavy metals (HMs) is fundamental for the management of food safety and security. However, a comprehensive and comparative view of the plant responses to different HMs is still lacking. Here, we compared root transcriptomes in common bean under 9 HM treatments at 50 μM for three time points each. Cd, Cr, Co, Ni, and Pb caused most severe morphological and/or biochemical retardations. A total of 448 genes were found to be responsive to all nine HMs, which were mostly involved in photosynthesis, oxidization-reduction, and ion binding. Cd and Cu triggered the greatest number of unique differentially expressed genes (DEG)s, which were predominantly related to cellular transport/localization in the former and RNA binding in the latter. Short-term and prolonged HM treatments shaped very different DEG patterns. Weighted gene co-expression network analysis identified six co-expression modules showing exceptionally high transcripts abundance in specific HM × time scenarios. We experimentally verified the promoter activity of the gene GIP1 and the novel function of XTH23 under Cu/Cd stress. Collectively, the transcriptomic atlas provides valuable resources for better understanding the common and unique mechanisms of plant response to different HMs and offers a mass of candidate target genes/promoters for genetic engineering.

Diurnal accumulation of K+-dependent L-asparaginase in leaf of common bean (Phaseolus vulgaris L.)

L-Asparaginase (EC 3.5.1.1) activity has been previously reported to fluctuate with the photoperiod in young pea leaves, with higher activity in the light. The present research sought to investigate this phenomenon in developing leaves of common bean (Phaseolus vulgaris L.). There are two genes coding for K⁺-dependent asparaginase in this species. Expression of PvASPG1 predominates over PvASPG2 in all tissues. The catalytic efficiency of recombinant PvASPG2 was approximately 2-fold lower than that of PvASPG1. Polyclonal antibodies were raised against a specific peptide present in PvASPG1 to use in immunoblotting. In developing seed, asparaginase protein levels in the seed coat stayed constant, whereas levels in cotyledon were lower and progressively declined. In young leaf, asparagine protein levels showed diurnal variation, increasing at the end of the dark period and slowly decreasing during the light period. This was paralleled by changes in activity levels in leaf extracts. These changes accompanied a transient increase in free asparagine concentration at the beginning of the light period. The present results demonstrated that K⁺-dependent asparaginase activity reaches a maximum level at the transition from dark to light, anticipating dawn, in young leaves of common bean.

Assessment of selenium and zinc enriched sludge and duckweed as slow-release micronutrient biofertilizers for Phaseolus vulgaris growth

Selenium (Se) and zinc (Zn) are essential micronutrients that are often lacking in the diet of humans and animals. Application of mineral Se and Zn fertilizers into soils may lead to a waste of Se and Zn due to the fast leaching and low utilization by plants. Slow-release Se and Zn biofertilizer may therefore be beneficial. This study aims to assess the potential of SeZn-enriched duckweed and sludge produced from wastewater as slow-release Se and Zn biofertilizers. Pot experiments with green beans (Phaseolus vulgaris) and sampling of Rhizon soil pore water were conducted to evaluate the bioavailability of Se and Zn in sandy and loamy soils mixed with SeZn-enriched duckweed and sludge. Both the Se and Zn concentrations in the soil pore water increased upon amending the two biomaterials. The concentration of Se released from SeZn-enriched duckweed rapidly decreased in the first 21 days and slowly declined afterwards, while it remained stable during the entire experiment upon application of SeZn-enriched sludge. The Zn content in the soil pore water gradually increased over time. The application of SeZn-enriched duckweed and sludge significantly increased the Se concentrations in plant tissues, in particular in the form of organic Se-methionine in seeds, without a negative impact on plant growth when an appropriate dose was applied (1 mg Se/kg soil). While, it did not increase Zn concentrations in plant seeds. The results indicate that the SeZn-enriched duckweed and sludge could be only used as organic Se biofertilizers for Se-deficient soils. Particularly, the SeZn-enriched sludge dominated with elemental nano-Se was an effective Se source and slow-release Se biofertilizer. These results could offer a theoretical reference to choose an alternative to chemical Se fertilizers for biofortification, avoiding the problem of Se losses by leaching from mineral Se fertilizers while recovering resources from wastewater. This could contribute to the driver for a future circular economy.

via the modulation of antioxidant and redox systems

The present study represents new evidence of the successful use of metal oxide nanoparticles in the remediation of heavy metals. Zinc oxide nanoparticles (ZnO NP) and copper oxide nanoparticles (CuO NP) were assessed to alleviate cadmium (Cd) toxicity in Phaseolus vulgaris L. seedlings and plants. Monitoring physiological and metabolic parameters allowed to elucidate Cd mechanism and process whereby it exerts phytotoxic effects on bean. The response of P. vulgaris seedlings is NP dose-dependent (10 mg/L, 50 mg/L, 100 mg/L, and 200 mg/L). Similarly, applied concentrations triggered a differential response of growing plants in terms of length and biomass. Our physiological data allowed to select 100 mg/L as the most appropriate concentration to apply, in order to avoid any risk of phytotoxicity. The regulatory mechanisms by which ZnO NP and CuO NP act are for the first time compared in the embryonic axes of bean seedlings under Cd stress. Both NP were able to reduce the hypergeneration of hydrogen peroxide (H₂O₂). They also acted via enhancing ROS scavenging enzymatic capacity, and activity of antioxidant enzymes CAT, APX, GPOX, GPX, and GR, and inhibited the activity of ROS producing enzymes such as GOX and NOX. Another mechanistic effect of NP consisted of the modulation of redox enzymes Trx, NTR, Fd, and FNR evolved in cellular homeostasis and maintaining reduced status in cells. Taken together, ZnO NP triggered more significant metabolic regulations allowing to mitigate the oxidative damage caused by Cd.

Modeling root loss reveals impacts on nutrient uptake and crop development

Despite the widespread prevalence of root loss in plants, its effects on crop productivity are not fully understood. While root loss reduces the capacity of plants to take up water and nutrients from the soil, it may provide benefits by decreasing the resources required to maintain the root system. Here, we simulated a range of root phenotypes in different soils and root loss scenarios for barley (Hordeum vulgare), common bean (Phaseolus vulgaris), and maize (Zea mays) using and extending the open-source, functional-structural root/soil simulation model OpenSimRoot. The model enabled us to quantify the impact of root loss on shoot dry weight in these scenarios and identify in which scenarios root loss is beneficial, detrimental, or has no effect. The simulations showed that root loss is detrimental for phosphorus uptake in all tested scenarios, whereas nitrogen uptake was relatively insensitive to root loss unless main root axes were lost. Loss of axial roots reduced shoot dry weight for all phenotypes in all species and soils, whereas lateral root loss had a smaller impact. In barley and maize plants with high lateral branching density that were not phosphorus-stressed, loss of lateral roots increased shoot dry weight. The fact that shoot dry weight increased due to root loss in these scenarios indicates that plants overproduce roots for some environments, such as those found in high-input agriculture. We conclude that a better understanding of the effects of root loss on plant development is an essential part of optimizing root system phenotypes for maximizing yield.

Rhizobia Contribute to Salinity Tolerance in Common Beans (Phaseolus vulgaris L.)

Rhizobia are soil bacteria that induce nodule formation on leguminous plants. In the nodules, they reduce dinitrogen to ammonium that can be utilized by plants. Besides nitrogen fixation, rhizobia have other symbiotic functions in plants including phosphorus and iron mobilization and protection of the plants against various abiotic stresses including salinity. Worldwide, about 20% of cultivable and 33% of irrigation land is saline, and it is estimated that around 50% of the arable land will be saline by 2050. Salinity inhibits plant growth and development, results in senescence, and ultimately plant death. The purpose of this study was to investigate how rhizobia, isolated from Kenyan soils, relieve common beans from salinity stress. The yield loss of common bean plants, which were either not inoculated or inoculated with the commercial R. tropici rhizobia CIAT899 was reduced by 73% when the plants were exposed to 300 mM NaCl, while only 60% yield loss was observed after inoculation with a novel indigenous isolate from Kenyan soil, named S3. Expression profiles showed that genes involved in the transport of mineral ions (such as K⁺, Ca²⁺, Fe³⁺, PO₄^3-, and NO₃^-) to the host plant, and for the synthesis and transport of osmotolerance molecules (soluble carbohydrates, amino acids, and nucleotides) are highly expressed in S3 bacteroids during salt stress than in the controls. Furthermore, genes for the synthesis and transport of glutathione and γ-aminobutyric acid were upregulated in salt-stressed and S3-inocculated common bean plants. We conclude that microbial osmolytes, mineral ions, and antioxidant molecules from rhizobia enhance salt tolerance in common beans.

plant and evaluation of its bioaccumulation and translocation by electrochemical methods

The objective of this work is to study the toxicological effect of the imidacloprid (IMD) on common bean plants (Phaseolus vulgaris L) when used at high doses and its quantification by electrochemical method. Common bean plants were exposed to increasing concentrations of IMD and the different plant tissues were subjected to various analyses. The IMD detection in different tissues of the bean plant was performed after extraction on the metallic silver electrode using square wave voltammetry. The analytical and calibration parameters (Slope, correlation coefficient, linear range, detection limit and relative standard deviation) were calculated for the different plant tissues. The effect of different doses (5.0 × 10^-3 to 5.0 × 10^-2 mol L^-1) of IMD was evaluated on germination, seedling (vigour, growth) and photosynthetic pigments in the bean plant. The results indicate that germination rate and seed vigour index reduced significantly (p ≤ 0.05) only in the applied concentrations above the recommended dose. A similar effect of IMD was observed on seedling development in term of roots length, plant length, number of leaves and number of nods. Concerning pigments content, chlorophyll a, b and total chlorophyll maximally decreased by 95.26%, 80.44% and 82.15% respectively at high applied dose. The bioaccumulation and translocation behaviour of IMD in bean plant was investigated, revealing that the IMD can be bioaccumulated in roots and can easily be translocated into stems and leaves.

Iodine biofortification of bean (Phaseolus vulgaris L.) and pea (Pisum sativum L.) plants cultivated in three different soils

An important challenge for mankind today is to find a plant-based source of iodine, instead of table salt, which would provide the recommended daily dosage of iodine. The aim of this work was to study the accumulation of iodine and the physiochemical changes in bean (Phaseolus vulgaris L.) and pea (Pisum sativum L.) irrigated with iodine-containing water. Applying iodine at concentration of 0.5 mg L-1 resulted 51, 18, and 35% decrement in biomass of bean fruit, while in pea fruit, a 13% reduction and a 3 and 2% increment were observed when the plants were cultivated in sand, sandy silt, and silt, respectively. The highest iodine concentrations in the bean and pea fruits were detected in plants cultivated in silt soil with concentration of 0.5 mg I- L-1 and amounted to 1.6 and 0.4 mg kg-1, respectively. In presence of iodine at concentration of 0.5 mg L-1, the concentration of magnesium, phosphorous, manganese and iron increased in the bean fruit, while in the case of pea, at iodine concentration above 0.1 mg L-1 the uptake of these nutrients were hampered. Based on these facts, the iodized bean can be recommended as a possible food source to enhance the iodine intake.

Managing White Mold on Common Bean with Type III Growth Habit by Integrating Partial Resistance, Plant Density, and Fungicide

The combination of plant density, fungicide, and levels of genotype resistance to white mold (WM) has not been studied for its effect on performance of common bean with type III growth habit under WM pressure. We established four sprinkler-irrigated trials in the fall to winter season in Brazil, combining density (8, 14, 20, or 26 plants/m²), genotype (susceptible or partially resistant to WM), and fungicide to manage WM (two fluazinam applications or without fluazinam) at 0.5 m row spacing in fields infested with sclerotia. One trial was established in a warm region, aiming to obtain low WM pressure. For three trials, the linear mixed model was used. WM pressure in the trials ranged from low to high. Genotype × density × fungicide and genotype × density interactions were not significant for incidence, severity, and yield for all trials. In the three trials, severity was 29% lower at eight than at 26 plants/m², and yield at 14 plants/m² (3,294 kg/ha) was 14% higher than yield at eight plants/m² (P = 0.035) where fluazinam was applied. However, without fluazinam, density did not affect yield. In conclusion, choices of plant density for type III bean cultivars do not need to take into account their resistance levels to WM in the fall to winter season. However, fungicide treatment to manage WM affects the choice of density, with 8 to 12 plants/m² recommended if fungicide is not an option to manage WM (as in organic systems), and 10 to 14 plants/m² recommended if fungicide applications are likely.

Efficacy of hot water treatment for postharvest control of western flower thrips, Frankliniella occidentalis, in French beans

BACKGROUND

The western flower thrips, Frankliniella occidentalis, is a quarantine pest of French beans that requires phytosanitary treatment to meet quarantine requirements for strict lucrative markets. In this study, the efficacy of hot water treatment against F. occidentalis eggs and its effects on the postharvest physicochemical quality parameters of French beans was evaluated.

RESULTS

The immersion time of 8.01 min (95% critical limits CL 7.77-8.24) was predicted by the probit model as the minimum time required to achieve a 99.9968% control level. Confirmatory tests with a large number of F. occidentalis eggs were performed to validate the estimated time to achieve probit-9 control level, and there were no survivors from the 50 103 eggs treated. Likewise, none of the 55 364 eggs exposed to 45 ± 0.2 °C for 7 min (observational time) survived. The effect of the treatment schedule on French beans quality parameters was assessed and there were no differences in weight loss, moisture content, total soluble solids, titratable acidity, pH, and reducing sugars between treated and untreated samples.

CONCLUSION

Our results indicate that hot water treatment (at 45 ± 0.2 °C for a duration of 8.01 min is an effective phytosanitary treatment for the control of Frankliniella occidentalis on French beans, with no significant impact on pods quality. © 2022 Society of Chemical Industry.

Comparison of Glycemic Response to Carbohydrate Meals without or with a Plant-Based Formula of Kidney Bean Extract, White Mulberry Leaf Extract, and Green Coffee Extract in Individuals with Abdominal Obesity

Due to the rising prevalence of obesity and type 2 diabetes, a strategy that can positively influence diet quality in a simple way is being explored, since a low glycemic index (GI) diet is advised in the dietoprophylaxis and diet therapy of diabetes. Methods: Twenty-three women with abdominal obesity participated in the study. The postprandial glycemic response and glycemic index were determined after three carbohydrate meals (noodle soup, white rice, strawberry sorbet) without or with the addition of a plant-base supplement (extracts of kidney bean, white mulberry leaf, and green coffee) with a potentially hypoglycemic effect. For two products (instant noodle soup and white rice), the addition of the plant supplement resulted in a reduction in glicemic iAUC values (respectively, by: 17.1%, p = 0.005 and 5.3%; p = 0.03; 40.6%, p = 0.004 and 5.3%, p = 0.019). However, this effect was not observed for strawberry sorbet. The blood glucose concentrations 30 min after the consumption of instant noodle soup and white rice with the plant-based formula addition significantly affected the GI value of tested meals (p = 0.0086, r = 0.53; p = 0.0096, r = 0.53), which may indicate the effect of this plant supplement on enterohormone and/or insulin secretion. Conclusion: A formula containing kidney bean, white mulberry leaves, and green coffee extracts may therefore be a notable factor in lowering postprandial glycemia and the GI of carbohydrate foods. However, further research is needed to determine for which food groups and meals its use may be most effective.

Leaves Increase Short-Chain Fatty Acid (SCFA) Production, Ameliorating Early Metabolic Alterations

High-fat/high-fructose diets promote early metabolic disorders in weight and lipid and glucose metabolism. Bioactive compounds such as polyphenols and fiber present in plant-based food prevent the development of metabolic disorders. The objective of the present study was to evaluate the effect of Phaseolus vulgaris L. Flor de Mayo Eugenia (FME) bean leaves on early metabolic alterations in male Wistar rats fed a high-fat/high-fructose diet. After proximate and chemical analysis of FME bean leaves, thirty-six male Wistar rats (ethical approval 06FCN2019 and 77FCN2019) were randomly assigned to one of four groups: 1) standard diet (S) fed with Rodent Laboratory Chow 5001®; 2) standard diet + 10% dry FME bean leaves (SBL); 3) high-fat (lard) and high-fructose diet (H); and 4) high-fat/high-fructose diet + 10% dry FME bean leaves (HBL). The study was carried out for six weeks. Group H exhibited early metabolic alterations compared to Group S: final weight gain (↑15%), abdominal fat accumulation (waist circumference, ↑11%), triglycerides (↑30%), glucose (↑16%), insulin resistance (HOMA-IR, ↑32%), and fecal triglycerides (↑284%) and decreased total short-chain fatty acids (SCFAs, ↓17%). FME bean leave supplementation (HBL) prevented body weight gain (↓12%), abdominal fat accumulation (waist circumference, ↓10%), and early insulin resistance (glucose area under the curve, ↓6%) compared to Group H. The supplementary bean leave diet increased SCFA production (↑54%), most likely mediated by the fiber and polyphenols present in the leaves. Therefore, bean leaves are a low-cost alternative for human nutritional care and prevention of early metabolic alterations.

Survey for Virus Diversity in Common Bean (Phaseolus vulgaris) Fields and the Detection of a Novel Strain of Cowpea polerovirus 1 in Zambia

The production of common bean (Phaseolus vulgaris L.) is adversely affected by virus-like diseases globally, but little is known about the occurrence, distribution, and diversity of common bean-infecting viruses in Zambia. Consequently, field surveys were conducted during the 2018 season in 128 fields across six provinces of Zambia and 640 common bean leaf tissue samples were collected with (n = 585) or without (n = 55) symptoms. The prevalence of symptomatic fields was 100%, but incidence of symptomatic plants ranged from 32 to 67.5%. Metagenomic analyses of nine composite samples and a single plant sample of interest revealed the occurrence of isolates of Bean common mosaic necrosis virus, Bean common mosaic virus, Cowpea aphid-borne mosaic virus, Peanut mottle virus, Southern bean mosaic virus (SBMV), Cucumber mosaic virus, Phaseolus vulgaris alphaendornavirus 1 (PvEV-1), PvEV-2, Ethiopian tobacco bushy top virus (ETBTV), and a novel strain of Cowpea polerovirus 1 (CPPV1-Pv) of 5,902 nt in length. While CPPV1-Pv was consistently detected in mixed infection with ETBTV and its satellite RNA molecule, based on results of mechanical transmission assays it does not appear to be involved in disease etiology, suggesting that its role may be limited to being a helper virus for the umbravirus. Screening of the survey samples by real-time PCR for the viruses detected by high-throughput sequencing revealed the prevalence of single (65.2% or 417/640) over mixed (1.9% or 12/640) infections in the samples. SBMV was the most frequently detected virus, occurring in ∼29.4% (188/640) of the samples and at a prevalence rate of 58.6% (75/128) across fields. The results showed that diverse virus species are present in Zambian common bean fields and the information will be useful for the management of common bean viral diseases.

Effect of copper stress on Phaseolus coccineus in the presence of exogenous methyl jasmonate and/or Serratia plymuthica from the Spitsbergen soil

Copper stress in the presence of exogenous methyl jasmonate and Serratia plymuthica in a complete trifactorial design with copper (0, 50 µM), methyl jasmonate (0, 1, 10 µM) and Serratia plymuthica (without and with inoculation) was studied on the physiological parameters of Phaseolus coccineus. Copper application reduced biomass and allantoin content, but increased chlorophyll and carotenoids contents as well as catalase and peroxidases activities. Jasmonate did not modify biomass and organic acids levels under copper treatment, but additional inoculation elevated biomass and content of tartrate, malate and succinate. Jasmonate used alone or in combination with bacteria increased superoxide dismutase activity in copper application. With copper, allantoin content elevated at lower jasmonate concentration, but with additional inoculation - at higher jasmonate concentration. Under copper stress, inoculation resulted in higher accumulation of tartrate, malate and citrate contents in roots, which corresponded with lower allantoin concentration in roots. Combined with copper, inoculation reduced catalase and guaiacol peroxidase activities, whereas organic acids content was higher. Under metal stress, with bacteria, jasmonate reduced phenolics content, elevated superoxide dismutase and guaiacol peroxidase activities. The data indicate that jasmonate and S. plymuthica affected most physiological parameters of P. coccineus grown with copper and revealed some effect on biomass.

Chemical seed treatment and mycorrhizal inoculation provide better development and nutrition of common bean plants

BACKGROUND

Chemical seed treatment is an established practice in agriculture to protect crops from soil-borne pathogens and pests. Arbuscular mycorrhizal fungi (AMF) benefit plants by extending soil exploration as well as water and nutrient uptake. The objective of this work was to analyze the effects of combinations of seed treatments with doses of inoculant containing Rhizoglomus intraradices on vegetative development, root colonization and nutrition of Phaseolus vulgaris plants and soil microbiota.

RESULTS

Seed treatment benefited the vegetative development and nutrition of beans, with the treatments metalaxyl + fludioxonil + tiabendazole and pyraclostrobin + thiophanate methyl + fipronil standing out regarding the contents of nitrogen (N), phosphorus (P), iron (Fe) and zinc (Zn) of the aerial parts. Mycorrhizal inoculation linearly increased dehydrogenase activity, root biomass and total plant biomass, with increments reaching 27%. There was an interaction between seed treatment and inoculation dose for aboveground biomass and the contents of potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), manganese (Mn) and root colonization, with expressive results for the combination of the two highest doses of inoculant with metalaxyl + fludioxonil + tiabendazole or pyraclostrobin + methylthiophanate + fipronil in the seeds.

CONCLUSION

Chemical seed treatment and mycorrhizal inoculation benefited bean plants and their nutritional status. The best combinations for the bean crop were metalaxyl + fludioxonil + tiabendazole with 41.4 mg of the inoculant per 100 seeds and pyraclostrobin + thiophanate methyl + fipronil with 62.1 mg of the inoculant per 100 seeds. © 2022 Society of Chemical Industry.