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Naciri R, Chtouki M, Oukarroum A. Mechanisms of cadmium mitigation in tomato plants under orthophosphate and polyphosphate fertilization regimes. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 274:116219. [PMID: 38492483 DOI: 10.1016/j.ecoenv.2024.116219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 03/06/2024] [Accepted: 03/13/2024] [Indexed: 03/18/2024]
Abstract
Cadmium (Cd) is one of the most toxic elements in soil, affecting morphological, physiological, and biochemical processes in plants. Mineral plant nutrition was tested as an effective approach to mitigate Cd stress in several crop species. In this regard, the present study aimed to elucidate how different phosphorus (P) fertilization regimes can improve some bio-physiological processes in tomato plants exposed to Cd stress. In a hydroponic experiment, the impact of two phosphorus fertilizer forms (Polyphosphate (poly-P): condensed P-form with 100% polymerization rate and orthophosphate (ortho-P): from orthophosphoric acid) on the photosynthetic activity, plant growth, and nutrient uptake was assessed under three levels of Cd stress (0, 12, and 25 µM of CdCl2). The obtained results confirmed the negative effects of Cd stress on the chlorophyll content and the efficiency of the photosynthesis machinery. The application of poly-P fertilizer significantly improved the chlorophyll stability index (82%) under medium Cd stress (Cd12), as compared to the ortho-P form (55%). The analysis of the chlorophyll α fluorescence transient curve revealed that the amplitude of Cd effect on the different steps of electron transfer between PSII and PSI was significantly reduced under the poly-P fertilization regime compared to ortho-P, especially under Cd12. The evaluation of the RE0/RC parameter showed that the electron flux reducing end electron acceptors at the PSI acceptor side per reaction center was significantly improved in the poly-P treatment by 42% under Cd12 compared to the ortho-P treatment. Moreover, the use of poly-P fertilizer enhanced iron uptake and its stoichiometric homeostasis in the shoot tissue which maintained an adequate absorption of iron under Cd stress conditions. Findings from this study revealed for the first time that inorganic polyphosphate fertilizers can reduce Cd toxicity in tomato plants by enhancing photosynthesis activity, nutrient uptake, plant growth, and biomass accumulation despite the high level of cadmium accumulation in shoot tissues.
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Affiliation(s)
- Rachida Naciri
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, Morocco.
| | - Mohamed Chtouki
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, Morocco
| | - Abdallah Oukarroum
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, Morocco
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2
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Dhiman A, Thaper P, Bhardwaj D, Agrawal G. Biodegradable Dextrin-Based Microgels for Slow Release of Dual Fertilizers for Sustainable Agriculture. ACS APPLIED MATERIALS & INTERFACES 2024; 16:11860-11871. [PMID: 38410836 DOI: 10.1021/acsami.3c16670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
In this research, we report dextrin-based biodegradable microgels (PDXE MGs) having phosphate-based cross-linking units for slow release of urea and a potential P source to improve fertilization. PDXE MGs (∼200 nm) are synthesized by cross-linking the lauroyl-functionalized dextrin chains with sodium tripolyphosphate. The developed PDXE MGs exhibit high loading (∼10%) and encapsulation efficiency (∼88%) for urea. It is observed that functionalization of PDXE MGs with lauroyl chains slows down the release of urea (90% in ∼24 days) as compared to nonfunctionalized microgels (PDX MGs) (99% in ∼17 days) in water. Further studies of the developed formulation display that Urea@PDXE MGs significantly boost maize seed germination and overall plant growth as compared to pure urea fertilizer. Moreover, analysis of maize leaves obtained from plants treated with Urea@PDXE MGs reveals 3.5 ± 0.3% nitrogen content and 90 ± 0.7 mg/g chlorophyll content. These values are significantly higher than 1.4 ± 0.6% nitrogen content and 48 ± 0.05 mg/g chlorophyll content obtained by using bare urea. Further, acid phosphatase activity in roots is reduced upon treatment with PDXE MGs and Urea@PDXE MGs, suggesting the availability of P upon degradation of PDXE MGs by the amylase enzyme in soil. These experimental results present the developed microgel-based biodegradable formulation with a slow release feature as a potential candidate to move toward sustainable agriculture practices.
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Affiliation(s)
- Ankita Dhiman
- School of Chemical Sciences and Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175075, India
| | - Piyush Thaper
- School of Chemical Sciences and Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175075, India
| | - Dimpy Bhardwaj
- School of Chemical Sciences and Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175075, India
| | - Garima Agrawal
- School of Chemical Sciences and Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175075, India
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Chtouki M, Naciri R, Oukarroum A. A review on phosphorus drip fertigation in the Mediterranean region: Fundamentals, current situation, challenges, and perspectives. Heliyon 2024; 10:e25543. [PMID: 38333855 PMCID: PMC10850969 DOI: 10.1016/j.heliyon.2024.e25543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 01/16/2024] [Accepted: 01/29/2024] [Indexed: 02/10/2024] Open
Abstract
The Mediterranean agricultural sector faces many challenges related to water and mineral resource use for crop production and food security for an exponentially growing population. Phosphorus drip fertigation has recently emerged as an efficient and sustainable technique to improve water and nutrient use efficiency under such challenging pedoclimatic conditions. The classical methods for administering standard P fertilizers to crops (broadcasting and banding) have shown their limitations in terms of P acquisition and use efficiency. More than 60 % of applied P through dry P fertilizers is rapidly transformed into recalcitrant P forms and subsequently lost by soil erosion increasing the effects of P eutrophication issues on the ecosystem's sustainability. The emergence of new advanced irrigation technologies like high-frequent drip irrigation must be accompanied by the development of new P formulations with high water solubility and greater P use efficiency. This review illustrates the state of the art for P fertilizers used in Mediterranean agriculture in the last decades. An overall description is provided for the P fertilizer formulas, their physicochemical properties, as well as their suitability for drip fertigation systems and the consequent effects of their application on photosynthesis, plant growth, and crop productivity. The key factors influencing P fertilizer transformations and use efficiency under drip fertigation systems are extensively discussed in this review with a focus on the differences between orthophosphate and polyphosphate formulations.
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Affiliation(s)
- Mohamed Chtouki
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, 43150, Morocco
| | - Rachida Naciri
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, 43150, Morocco
| | - Abdallah Oukarroum
- Plant Stress Physiology Laboratory, College of Agriculture and Environmental Sciences, Mohammed VI Polytechnic University, Benguerir, 43150, Morocco
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Loudari A, Latique S, Mayane A, Colinet G, Oukarroum A. Polyphosphate fertilizer impacts the enzymatic and non-enzymatic antioxidant capacity of wheat plants grown under salinity. Sci Rep 2023; 13:11212. [PMID: 37433920 DOI: 10.1038/s41598-023-38403-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 07/07/2023] [Indexed: 07/13/2023] Open
Abstract
By 2050, the predicted global population is set to reach 9.6 billion highlighting the urgent need to increase crop productivity to meet the growing demand for food. This is becoming increasingly challenging when soils are saline and/or deficient in phosphorus (P). The synergic effect of P deficiency and salinity causes a series of secondary stresses including oxidative stress. Reactive Oxygen Species (ROS) production and oxidative damage in plants caused either by P limitation or by salt stress may restrict the overall plant performances leading to a decline in crop yield. However, the P application in adequate forms and doses could positively impact the growth of plants and enhances their tolerance to salinity. In our investigation, we evaluated the effect of different P fertilizers forms (Ortho-A, Ortho-B and Poly-B) and increasing P rates (0, 30 and 45 ppm) on the plant's antioxidant system and P uptake of durum wheat (Karim cultivar) grown under salinity (EC = 3.003 dS/m). Our results demonstrated that salinity caused a series of variations in the antioxidant capacity of wheat plants, at both, enzymatic and non-enzymatic levels. Remarkably, a strong correlation was observed between P uptake, biomass, various antioxidant system parameters and P rates and sources. Soluble P fertilizers considerably enhanced the total plant performances under salt stress compared with control plants grown under salinity and P deficiency (C+). Indeed, salt-stressed and fertilized plants exhibited a robust antioxidant system revealed by the increase in enzymatic activities of Catalase (CAT) and Ascorbate peroxidase (APX) and a significant accumulation of Proline, total polyphenols content (TPC) and soluble sugars (SS) as well as increased biomass, Chlorophyll content (CCI), leaf protein content and P uptake compared to unfertilized plants. Compared to OrthoP fertilizers at 45 ppm P, Poly-B fertilizer showed significant positive responses at 30 ppm P where the increase reached + 18.2% in protein content, + 156.8% in shoot biomass, + 93% in CCI, + 84% in shoot P content, + 51% in CAT activity, + 79% in APX activity, + 93% in TPC and + 40% in SS compared to C+. This implies that PolyP fertilizers might be an alternative for the suitable management of phosphorus fertilization under salinity.
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Affiliation(s)
- Aicha Loudari
- Plant Stress Physiology Laboratory, Mohammed VI Polytechnic University (UM6P)-AgroBioSciences, Lot-660 Hay Moulay, Rachid, 43150, Ben Guerir, Morocco.
- Terra Research Center, Liege University-Gembloux Agro Bio Tech Faculty, 5030, Gembloux, Belgium.
| | - Salma Latique
- Plant Stress Physiology Laboratory, Mohammed VI Polytechnic University (UM6P)-AgroBioSciences, Lot-660 Hay Moulay, Rachid, 43150, Ben Guerir, Morocco
| | - Asmae Mayane
- Plant Stress Physiology Laboratory, Mohammed VI Polytechnic University (UM6P)-AgroBioSciences, Lot-660 Hay Moulay, Rachid, 43150, Ben Guerir, Morocco
| | - Gilles Colinet
- Terra Research Center, Liege University-Gembloux Agro Bio Tech Faculty, 5030, Gembloux, Belgium
| | - Abdallah Oukarroum
- Plant Stress Physiology Laboratory, Mohammed VI Polytechnic University (UM6P)-AgroBioSciences, Lot-660 Hay Moulay, Rachid, 43150, Ben Guerir, Morocco.
- High Throughput Multidisciplinary Research Laboratory, Mohammed VI Polytechnic University (UM6P), 43150, Ben Guerir, Morocco.
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Khourchi S, Elhaissoufi W, Ibnyasser A, Haddine M, Ghani R, Zeroual Y, Delaplace P, Bargaz A. Integrated use of polyphosphate and P-solubilizing bacteria enhanced P use efficiency and growth performance of durum wheat. Front Microbiol 2023; 14:1211397. [PMID: 37476670 PMCID: PMC10354339 DOI: 10.3389/fmicb.2023.1211397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 06/15/2023] [Indexed: 07/22/2023] Open
Abstract
Coupling phosphate-solubilizing bacteria (PSB) with P fertilizers, including polyphosphates (PolyP), was reported as eco-efficient approach to enhance P use efficiency. Although PSB have been recently reported to hydrolyze PolyP, the plant growth promoting mechanisms of PolyP-PSB co-application were not yet uncovered. This study aims to evaluate the effect of a PSB consortium (PSBCs) on growth, P use efficiency (PUE), and wheat yield parameters under PolyP (PolyB) application. Co-application of PolyB-PSBCs significantly enhanced wheat growth at 75 days after sowing (DAS) compared to 30 DAS. A significant increase in shoot dry biomass (47%), shoot inorganic P content (222%), PUE (91%), and root P absorption efficiency (RPAE, 99%) was noted compared to unfertilized plants. Similarly, the PolyB-PSBCs co-application enhanced morphological root traits at 30 DAS, while acid phosphatase activities (root and rhizosphere), RPAE, and PUE were significantly increased at 75 DAS. The improved wheat P acquisition could be attributed to a lower investment in root biomass production, and significant induction of acid phosphatase activity in roots and rhizosphere soil under PolyB-PSBCs co-application. Consequently, the PolyB-PSBCs co-application significantly improved aboveground performance, which is reflected by increased shoot nutrient contents (P 300%, K 65%), dry weight (54%), and number (50%) of spikes. Altogether, this study provides relevant evidence that co-application of PolyP-PSBCs can be an integrated and environmentally preferred P fertilization approach owing to the dual effects of PolyP and PSBCs on wheat PUE.
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Affiliation(s)
- Said Khourchi
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
- TERRA – Teaching and Research Center, Plant Sciences, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium
| | - Wissal Elhaissoufi
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Ammar Ibnyasser
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Meryem Haddine
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Rachid Ghani
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
| | - Youssef Zeroual
- Situation Innovation, OCP Group, Jorf Lasfar, El Jadida, Morocco
| | - Pierre Delaplace
- TERRA – Teaching and Research Center, Plant Sciences, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium
| | - Adnane Bargaz
- Agrobiosciences Program, College for Sustainable Agriculture and Environmental Sciences, , Mohammed VI Polytechnic University (UM6P), Ben Guerir, Morocco
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Bourak K, Sare AR, Allaoui A, Jijakli MH, Massart S. Impact of Two Phosphorus Fertilizer Formulations on Wheat Physiology, Rhizosphere, and Rhizoplane Microbiota. Int J Mol Sci 2023; 24:9879. [PMID: 37373026 DOI: 10.3390/ijms24129879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/29/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Phosphorus (P) is the second most important macronutrient for crop growth and a limiting factor in food production. Choosing the right P fertilizer formulation is important for crop production systems because P is not mobile in soils, and placing phosphate fertilizers is a major management decision. In addition, root microorganisms play an important role in helping phosphorus fertilization management by regulating soil properties and fertility through different pathways. Our study evaluated the impact of two phosphorous formulations (polyphosphates and orthophosphates) on physiological traits of wheat related to yield (photosynthetic parameters, biomass, and root morphology) and its associated microbiota. A greenhouse experiment was conducted using agricultural soil deficient in P (1.49%). Phenotyping technologies were used at the tillering, stem elongation, heading, flowering, and grain-filling stages. The evaluation of wheat physiological traits revealed highly significant differences between treated and untreated plants but not between phosphorous fertilizers. High-throughput sequencing technologies were applied to analyse the wheat rhizosphere and rhizoplane microbiota at the tillering and the grain-filling growth stages. The alpha- and beta-diversity analyses of bacterial and fungal microbiota revealed differences between fertilized and non-fertilized wheat, rhizosphere, and rhizoplane, and the tillering and grain-filling growth stages. Our study provides new information on the composition of the wheat microbiota in the rhizosphere and rhizoplane during growth stages (Z39 and Z69) under polyphosphate and orthophosphate fertilization. Hence, a deeper understanding of this interaction could provide better insights into managing microbial communities to promote beneficial plant-microbiome interactions for P uptake.
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Affiliation(s)
- Kaoutar Bourak
- Terra Research Center, Integrated and Urban Plant Pathology Laboratory, Liege University, Gembloux Agro-Bio-Tech, B-5030 Gembloux, Belgium
- Microbiology Laboratory, African Genome Center (AGC), Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
| | - Abdoul Razack Sare
- Terra Research Center, Integrated and Urban Plant Pathology Laboratory, Liege University, Gembloux Agro-Bio-Tech, B-5030 Gembloux, Belgium
| | - Abdelmounaaim Allaoui
- Microbiology Laboratory, African Genome Center (AGC), Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
| | - M Haissam Jijakli
- Terra Research Center, Integrated and Urban Plant Pathology Laboratory, Liege University, Gembloux Agro-Bio-Tech, B-5030 Gembloux, Belgium
| | - Sébastien Massart
- Terra Research Center, Integrated and Urban Plant Pathology Laboratory, Liege University, Gembloux Agro-Bio-Tech, B-5030 Gembloux, Belgium
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Yang B, Chen N, Dang Y, Wang Y, Wen H, Zheng J, Zheng X, Zhao J, Lu J, Qiao L. Identification and validation of quantitative trait loci for chlorophyll content of flag leaf in wheat under different phosphorus treatments. FRONTIERS IN PLANT SCIENCE 2022; 13:1019012. [PMID: 36466250 PMCID: PMC9714299 DOI: 10.3389/fpls.2022.1019012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 10/14/2022] [Indexed: 06/17/2023]
Abstract
In wheat, the leaf chlorophyll content in flag leaves is closely related to the degree of phosphorus stress. Identifying major genes/loci associated with chlorophyll content in flag leaves under different phosphorus conditions is critical for breeding wheat varieties resistant to low phosphorus (P). Under normal, medium, and low phosphorus conditions, the chlorophyll content of flag leaves was investigated by a double haploid (DH) population derived from a cross between two popular wheat varieties Jinmai 47 and Jinmai 84, at different grain filling stages. Chlorophyll content of the DH population and parents decreased gradually during the S1 to the S3 stages and rapidly at the S4 stage. At the S4 stage, the chlorophyll content of the DH population under low phosphorus conditions was significantly lower than under normal phosphate conditions. Using a wheat 15K single-nucleotide polymorphism (SNP) panel, a total of 157 QTLs were found to be associated with chlorophyll content in flag leaf and were identified under three phosphorus conditions. The phenotypic variation explained (PVE) ranged from 3.07 to 31.66%. Under three different phosphorus conditions, 36, 30, and 48 QTLs for chlorophyll content were identified, respectively. Six major QTLs Qchl.saw-2B.1, Qchl.saw-3B.1, Qchl.saw-4D.1, Qchl.saw-4D.2, Qchl.saw-5A.9 and Qchl.saw-6A.4 could be detected under multiple phosphorus conditions in which Qchl.saw-4D.1, Qchl.saw-4D.2, and Qchl.saw-6A.4 were revealed to be novel major QTLs. Moreover, the closely linked SNP markers of Qchl.saw-4D.1 and Qchl.saw-4D.2 were validated as KASP markers in a DH population sharing the common parent Jinmai 84, showed extreme significance (P <0.01) in more than three environments under different phosphorus conditions, which has the potential to be utilized in molecular marker-assisted breeding for low phosphorus tolerance in wheat.
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Affiliation(s)
- Bin Yang
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Nan Chen
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
- College of Agronomy, Shanxi Agricultural University, Taiyuan, China
| | - Yifei Dang
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
- College of Agronomy, Shanxi Agricultural University, Taiyuan, China
| | - Yuzhi Wang
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Hongwei Wen
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Jun Zheng
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Xingwei Zheng
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Jiajia Zhao
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Jinxiu Lu
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
| | - Ling Qiao
- Institute of Wheat Research, State Key Laboratory of Sustainable Dryland Agriculture, Shanxi Agricultural University, Linfen, China
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Loudari A, Mayane A, Zeroual Y, Colinet G, Oukarroum A. Photosynthetic performance and nutrient uptake under salt stress: Differential responses of wheat plants to contrasting phosphorus forms and rates. FRONTIERS IN PLANT SCIENCE 2022; 13:1038672. [PMID: 36438086 PMCID: PMC9684725 DOI: 10.3389/fpls.2022.1038672] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Salt stress impacts phosphorus (P) bioavailability, mobility, and its uptake by plants. Since P is involved in many key processes in plants, salinity and P deficiency could significantly cause serious damage to photosynthesis, the most essential physiological process for the growth and development of all green plants. Different approaches have been proposed and adopted to minimize the harmful effects of their combined effect. Optimising phosphorus nutrition seems to bring positive results to improve photosynthetic efficiency and nutrient uptake. The present work posed the question if soluble fertilizers allow wheat plants to counter the adverse effect of salt stress. A pot experiment was performed using a Moroccan cultivar of durum wheat: Karim. This study focused on different growth and physiological responses of wheat plants grown under the combined effect of salinity and P-availability. Two Orthophosphates (Ortho-A & Ortho-B) and one polyphosphate (Poly-B) were applied at different P levels (0, 30 and 45 ppm). Plant growth was analysed on some physiological parameters (stomatal conductance (SC), chlorophyll content index (CCI), chlorophyll a fluorescence, shoot and root biomass, and mineral uptake). Fertilized wheat plants showed a significant increase in photosynthetic performance and nutrient uptake. Compared to salt-stressed and unfertilized plants (C+), CCI increased by 93%, 81% and 71% at 30 ppm of P in plants fertilized by Poly-B, Ortho-B and Ortho-A, respectively. The highest significant SC was obtained at 45 ppm using Ortho-B fertilizer with an increase of 232% followed by 217% and 157% for both Poly-B and Ortho-A, respectively. The Photosynthetic performance index (PItot) was also increased by 128.5%, 90.2% and 38.8% for Ortho-B, Ortho-A and Poly B, respectively. In addition, Poly-B showed a significant enhancement in roots and shoots biomass (49.4% and 156.8%, respectively) compared to C+. Fertilized and salt-stressed plants absorbed more phosphorus. The P content significantly increased mainly at 45 ppm of P. Positive correlations were found between phosphorus uptake, biomass, and photosynthetic yield. The increased photochemical activity could be due to a significant enhancement in light energy absorbed by the enhanced Chl antenna. The positive effect of adequate P fertilization under salt stress was therefore evident in durum wheat plants.
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Affiliation(s)
- Aicha Loudari
- Plant Stress Physiology Laboratory–AgroBioSciences, Mohammed VI Polytechnic University (UM6P), Benguerir, Morocco
- Terra Research Center, Gembloux Agro Bio Tech Faculty, Liege University (ULIEGE), Gembloux, Belgium
| | - Asmae Mayane
- Plant Stress Physiology Laboratory–AgroBioSciences, Mohammed VI Polytechnic University (UM6P), Benguerir, Morocco
| | - Youssef Zeroual
- Plant Stress Physiology Laboratory–AgroBioSciences, Mohammed VI Polytechnic University (UM6P), Benguerir, Morocco
| | - Gilles Colinet
- Terra Research Center, Gembloux Agro Bio Tech Faculty, Liege University (ULIEGE), Gembloux, Belgium
| | - Abdallah Oukarroum
- Plant Stress Physiology Laboratory–AgroBioSciences, Mohammed VI Polytechnic University (UM6P), Benguerir, Morocco
- High Throughput Multidisciplinary Research Laboratory, Mohammed VI Polytechnic University (UM6P), Benguerir, Morocco
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