Effects of multiple N, P, and K fertilizer combinations on adzuki bean (Vigna angularis) yield in a semi-arid region of northeastern China

Foliar spraying exogenous ABA resists chilling stress on adzuki beans (Vigna angularis)

Adzuki bean, an important legume crop, exhibits poor tolerance to low temperatures. To investigate the effect of exogenous abscisic acid (ABA) on the physiological metabolism and yield resistance of adzuki bean under low-temperature stress, we conducted a potted experiment using Longxiaodou 4 (LXD 4) and Tianjinhong (TJH) as test materials and pre-sprayed with exogenous ABA at flowering stage continuously for 5 days with an average of 12°C and an average of 15°C, respectively. We found that, compared with spraying water, foliar spraying exogenous ABA increased the activities of antioxidants and the content of non-enzymatic antioxidants, effectively inhibited the increase of malondialdehyde (MDA), hydrogen peroxide (H2O2) content, O2-· production rate. Exogenous ABA induced the activation of endogenous protective mechanisms by increasing antioxidant enzymes activities such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), as well as elevated levels of non-enzymatic antioxidants including ascorbic acid (ASA) and glutathione (GSH). Moreover, the yield loss of 5.81%-39.84% caused by chilling stress was alleviated by spraying ABA. In conclusion, foliar spraying exogenous ABA can reduce the negative effects of low-temperature stress on the yield of Adzuki beans, which is essential to ensure stable production of Adzuki beans under low-temperature conditions.

Assessment of the Nutritional Value of Stems and Leaves of Australian Adzuki Bean

Adzuki bean has recently been proposed as a viable dual-purpose (grain-and-graze) crop for the Northern regions of Australia because of its successful use in semi-arid regions and its nitrogen fixation capacity to improve soil fertility and animal nutrition. However, there are very few studies on the phytochemical composition and nutritional value of the non-seed material. This study investigated the phenolic composition of the parts grown in the vegetative phase (leaves and stems) of nine Australian adzuki bean varieties for the first time. The total phenolic content (TPC) of the stem material (157-406 mg GAE/100 g) was 23-217% higher than that of commercial livestock feed, while the TPC of the leaf material (1158-1420 mg GAE/100 g) was 9-11 times higher. Using tandem liquid chromatography mass spectrometry (LC-MS), the major phenolic compounds identified were rutin, luteolin, salicylic acid, and quercetin-3-glucoside. The leaf and stem materials showed high levels of apparent in vitro dry matter digestibility, with no significant difference in total gas or methane production compared to lucerne hay. The results suggest that adzuki bean vegetative materials could be a high-value livestock fodder and support pursuing further in-depth studies into their nutritional value for livestock.

Comparison of the pretreatment methods for enhancing hydration of water-soaked adzuki beans (Vigna angularis)

Five pretreatments methods, cold plasma, pressure drop, heating, and bath-type and probe-type sonications were compared to shorten the rehydration process of adzuki bean (Vigna angularis) soaked before the cooking in terms of the hydration and softening efficacies. Moisture content and water activity of the probe-type sonicated beans were most dramatically increased as 11-45% and 0.59-0.97 after soaking for only 2 h, respectively (non-treated: 11-12% and 0.59-0.66). Accordingly, the probe-type sonicated beans were most rapidly softened as 27-5 N in the 2 h-soaking and exhibited the lowest hardness after soaking/cooking as ~ 0.97 N (non-treated: 27-21 N and ~ 5.5 N, respectively). According to scanning electron micrographs, these results can be attributed to formation of prominent fissures or scars in the hilum of the probe-type sonicated beans. Consequently, this study will be provide valuable information for developing a rational process in food industry to shorten the rehydration of the adzuki beans.

Yield and quality of alfalfa (Medicago sativa L.) in response to fertilizer application in China: A meta-analysis

INTRODUCTION

In China, alfalfa (Medicago sativa L.) often grows in marginal land with poor soil fertility and suboptimal climate conditions. Alfalfa production cannot meet demands both in yield and quality. It is necessary to apply fertilizers to achieve high yields and produce high-quality alfalfa in China. However, there is no understanding on the impact of fertilizer application on alfalfa production and the possible optimal application rates across China.

METHODS

We conducted a meta-analysis to explore the contribution of fertilizer application to the yield and quality of alfalfa based on a dataset from 86 studies published between 2004 and 2022.

RESULTS AND DISCUSSION

The results showed that fertilizer application not only increased alfalfa yield by 19.2% but also improved alfalfa quality by increasing crude protein (CP) by 7.7% and decreasing acid detergent fibre by 2.9% and neutral detergent fibre by 1.8% overall compared to the non-fertilizer control levels. The combined nitrogen (N), phosphorus (P) and potassium (K) and combined NP fertilizer applications achieved the greatest yield and CP concentration increases of 27.0% and 13.5%, respectively. Considering both yield and quality, the optimal rate of fertilizer application ranged from 30 to 60 kg ha^-1 for N, 120 to 150 kg ha^-1 for P and less than 120 kg ha^-1 for K. Meta-analysis further showed that the effect of fertilizer application on yield was greater in low soil organic matter (SOM) soils than in high SOM soils. In conclusion, fertilizer application is an effective strategy to improve the yield and quality of alfalfa in China, especially that grown in low SOM soils. This study is helpful for optimizing fertilization schedules of alfalfa in China.

Transcriptome Analysis of Short-Day Photoperiod Inducement in Adzuki Bean (Vigna angularis L.) Based on RNA-Seq

The flowering characteristics of adzuki bean are influenced by several environmental factors. Light is an important ecological factor that induces flowering in adzuki bean, but to date, there have been few reports on the transcriptomic features of photoperiodic regulation of adzuki bean flowering. This study is based on RNA sequencing (RNA-seq) techniques to elucidate the expression of light-related regulatory genes under short-day photoperiod inducement of adzuki bean flowering, providing an important theoretical basis for its accelerated breeding. Short-day photoperiod inducement of 10 h was conducted for 5 day, 10 day, and 15 day periods on "Tang shan hong xiao dou" varieties, which are more sensitive to short-day photoperiod conditions than the other varieties. Plants grown under natural light (14.5 h) for 5 days, 10 days, and 15 days were used as controls to compare the progress of flower bud differentiation and flowering characteristics. The topmost unfolded functional leaves were selected for transcriptome sequencing and bioinformatics analysis. The short-day photoperiod inducement promoted flower bud differentiation and advanced flowering time in adzuki bean. Transcriptomic analysis revealed 5,608 differentially expressed genes (DEGs) for the combination of CK-5d vs. SD-5d, CK-10d vs. SD-10d, and CK-15d vs. SD-15d. The three groups of the DEGs were analyzed using the Gene Ontology (GO) and the Kyoto Encyclopedia of Genomes and Genomes (KEGG) databases; the DEGs were associated with flowering, photosystem, and the circadian rhythm and were mainly concentrated in the hormone signaling and metabolism, circadian rhythm, and antenna protein pathways; So, 13 light-related genes across the three pathways were screened for differential and expression characteristics. Through the functional annotations of orthologs, these genes were related to flowering, which were supposed to be good candidate genes in adzuki bean. The findings provide a deep understanding of the molecular mechanisms of adzuki bean flowering in response to short-day photoperiod inducement, which laid a foundation for the functional verification of genes in the next step, and provide an important reference for the molecular breeding of adzuki bean.

Genetic Diversity and Environmental Influence on Yield and Yield-Related Traits of Adzuki Bean (Vigna angularis L.)

Adzuki beans are an important food legume crop in East Asia. A large number of adzuki bean accessions are maintained in the Chinese national seed genebank. A collection of 59 elite cultivars, 389 landraces, and 27 wild adzuki beans were selected and phenotyped extensively for yield and yield-related traits at two different locations (Nanning and Nanyang, China). Ten agronomic and yield-related traits were scored, and the data were subjected to analysis of variance (ANOVA), principal component analysis (PCA), correlation, and cluster analysis. Significant variation was observed for genotypes, locations, and genotype x environment interaction for most traits. Also, there were significant differences in the phenotypes among accessions of different germplasm types. The broad-sense heritability of traits studied ranged from 4.4% to 77.8%. The number of seeds per pod (77.8%), 100-seed weight (68.0%), and number of plant branches (63.9%) had a high heritability. A total of 10 traits were transformed into 3 comprehensive factors by principal component analysis, and the first three principal component factors contributed 72.31% of the total variability. Cluster analysis categorized the 475 adzuki bean accessions into five distinct groups. The results described in this study will be useful for adzuki bean breeders for the development of varieties with high end-use quality.

An Overview of the Practices and Management Methods for Enhancing Seed Production in Conifer Plantations for Commercial Use

Flowering, the beginning of the reproductive growth, is a significant stage in the growth and development of plants. Conifers are economically and ecologically important, characterized by straight trunks and a good wood quality and, thus, conifer plantations are widely distributed around the world. In addition, conifer species have a good tolerance to biotic and abiotic stress, and a stronger survival ability. Seeds of some conifer species, such as Pinus koraiensis, are rich in vitamins, amino acids, mineral elements and other nutrients, which are used for food and medicine. Although conifers are the largest (giant sequoia) and oldest living plants (bristlecone pine), their growth cycle is relatively long, and the seed yield is unstable. In the present work, we reviewed selected literature and provide a comprehensive overview on the most influential factors and on the methods and techniques that can be adopted in order to improve flowering and seed production in conifers species. The review revealed that flowering and seed yields in conifers are affected by a variety of factors, such as pollen, temperature, light, water availability, nutrients, etc., and a number of management techniques, including topping off, pruning, fertilization, hormone treatment, supplementary pollination, etc. has been developed for improving cone yields. Furthermore, several flowering-related genes (FT, Flowering locus T and MADS-box, MCMI, AGAMOUS, DEFICIENCES and SRF) that play a crucial role in flowering in coniferous trees were identified. The results of this study can be useful for forest managers and for enhancing seed yields in conifer plantations for commercial use.

Molecular Evaluation of Kyoho Grape Leaf and Berry Characteristics Influenced by Different NPK Fertilizers

Fertilization, a fundamental aspect of a plant’s life, has been of great concern for agricultural specialists to minimize the yield gap between actual and potential yield. Around the globe, fertilizers with different NPK ratios are being used to attain a better yield of grape. To find the suitable commercially available fertilizer for quality grape production, a 2 years (2017–2018) study was conducted for the evaluation of 10 fertilizers with different NPK ratios. Commercial fertilizers included were Zhanlan (16:16:16), Garsoni (15:15:15), Acron (16:16:16), Norway (21:7:12), Peters 1 (30:10:10), Nutrivant (14:14:30), Peters 2 (20:20:20), UMAX (15:15:15), G2 (20:20:20), and Yara (15:15:15). The fertilizer application rate was 20 g plant⁻¹, and each was applied at L-29, L-33, and L-36 phenological stages. Chlorophylls, carotenoids, macro/micronutrients in leaf, and anthocyanin derivatives in grape peel were evaluated. Expression levels of 24 genes, including nitrogen, phosphorous, potassium, and anthocyanin pathways in leaf, peel, and pulp were validated by qPCR at L-29, L-33, and L-36 stages. Results indicated that Norway (21:7:12) and Peters 1 (30:10:10) increased carotenoids, chlorophylls, and anthocyanins in leaves, while Zhanlan (16:16:16) improved fruit biochemical attributes, and anthocyanin (cyanidin, delphinidin, petunidin, malvidin, peonidin, and pelargonidin contents). However, a better grape yield was obtained by the application of Peters 1 (30:10:10). Potassium pathway genes were upregulated by Nutrivant (14:14:30), phosphorous pathway genes by Peters 2 (20:20:20), and nitrogen pathway genes by Peters 1 (30:10:10), while Nutrivant (14:14:30) upregulated anthocyanin pathway genes and simultaneously enhanced anthocyanin biosynthesis in berry peels. Results of two years’ study concluded that Peters 1 (30:10:10) was proved better to increase yield, while Zhanlan (14:14:30) was superior in improving anthocyanin biosynthesis.