Publications

Self-help groups engaged in development activities have the potential to empower their members through the provision of knowledge, skills, motivation, and competencies that underpin sustainable agriculture. There is a shortage of empirical data on the role of self-help groups in India; this study attempts to identify the effectiveness of farmer groups in improving the economic and social status of members by conducting a case study on two self-help groups in Punjab, India. The analysis revealed that, besides contributing toward economic development, these groups are important for social networking. While social activities are more prominent among groups with members who are wealthier, larger groups with more wealthy members mainly sought access to advanced technical information. Group involvement helps to establish appropriate marketing relationships and to minimize input costs. The results of the analysis indicate that both case study groups have the essential characteristics for effective group operation and are working successfully.

Moss-dominated biocrusts (moss crusts) are a feasible approach for the ecological restoration of drylands, but difficulty obtaining inoculum severely limits the progress of large-scale field applications. Exogenous microorganisms could improve moss growth and be conducive to moss inoculum propagation. In this study, we investigated the growth-promoting effects and potential mechanisms of exogenous microorganism additives on moss crusts. We used an incubator study to examine the effects of inoculation by heterotrophic microorganisms (<i>Streptomyces pactum</i>, <i>Bacillus megaterium</i>) and autotrophic microorganisms (<i>Chlorella vulgaris</i>, <i>Microcoleus vaginatus</i>) combined with <i>Artemisia sphaerocephala</i> gum on the growth of <i>Bryum argenteum</i>, the dominant moss crusts species in sandy deserts. Amplicon sequencing (16S and 18S rRNA) and PICRUSt2 were used to illustrate the microbial community structure and potential function in the optimal treatment at different developmental stages. Our results showed that exogenous microorganisms significantly promoted moss growth and increased aboveground biomass. After 30 days of cultivation, the <i>Streptomyces pactum</i> (1 g kg^-1 substrate) + <i>Chlorella vulgaris</i> (3.33 L m^-2) treatment presented optimal moss coverage, height, and density of 97.14%, 28.31 mm, and 2.28 g cm^-2, respectively. The best-performing treatment had a higher relative abundance of Streptophyta-involved in moss growth-than the control. The control had significantly higher soil organic carbon than the best-performing treatment on day 30. Exogenous microorganisms improved eukaryotic community diversity and richness and may enhance soil microbial functional and metabolic diversity, such as growth and reproduction, carbon fixation, and cellulose and lignin decomposition, based on functional predictions. In summary, we identified the growth-promoting mechanisms of exogenous additives, providing a valuable reference for optimizing propagation technology for moss inoculum.

Flowering Chinese cabbage (<i>Brassica campestris</i> L. ssp. <i>chinensis</i> var. <i>utilis</i> Tsen et Lee, 2n=20, AA) is a vegetable species in southern parts of China that faces high temperatures in the summer and winter seasons. While heat stress adversely impacts plant productivity and survival, the underlying molecular and biochemical causes are poorly understood. This study investigated the gene expression profiles of heat-sensitive (HS) '3T-6' and heat-tolerant (HT) 'Youlu-501' varieties of flowering Chinese cabbage in response to heat stress using RNA sequencing. Among the 37,958 genes expressed in leaves, 20,680 were differentially expressed genes (DEGs) at 1, 6, and 12 h, with 1,078 simultaneously expressed at all time points in both varieties. Hierarchical clustering analysis identified three clusters comprising 1,958, 556, and 591 down-regulated, up-regulated, and up- and/or down-regulated DEGs (3205 DEGs; 8.44%), which were significantly enriched in MAPK signaling, plant-pathogen interactions, plant hormone signal transduction, and brassinosteroid biosynthesis pathways and involved in stimulus, stress, growth, reproductive, and defense responses. Transcription factors, including MYB (12), NAC (13), WRKY (11), ERF (31), HSF (17), bHLH (16), and regulatory proteins such as PAL, CYP450, and photosystem II, played an essential role as effectors of homeostasis, kinases/phosphatases, and photosynthesis. Among 3205 DEGs, many previously reported genes underlying heat stress were also identified, e.g., <i>BraWRKY25, BraHSP70, BraHSPB27, BraCYP71A23, BraPYL9</i>, and <i>BraA05g032350.3C</i>. The genome-wide comparison of HS and HT provides a solid foundation for understanding the molecular mechanisms of heat tolerance in flowering Chinese cabbage.

Abstract Biofertilizers has potential to improve crop productivity in a sustainable manner yet their impact on forage crops yields and forage quality indices have not been extensively explored. In this study, the impact of different cropping patterns and fertilizer sources on the forage yield and quality of ajowan ( Carum copticum L.), fenugreek ( Trigonella foenum‐graecum L.), and pea ( Pisum sativum L.) was investigated. The findings shed light on the importance of biofertilizer application as a sustainable solution for enhancing forage production and quality in agricultural systems. The experimental treatments involved six cropping patterns [ajowan monoculture, fenugreek monoculture, pea monoculture, intercropping of one row ajowan + one row fenugreek + one row pea (1:1:1), two rows ajowan + two rows fenugreek + two rows pea (2:2:2), and three rows ajowan + three rows fenugreek + three rows pea (3:3:3)] and five fertilizer sources [no fertilizer (control), 100% chemical fertilizer (CF), chemical fertilizer + humic acid (CF + HU), chemical fertilizer + biofertilizer (CF + BF), and humic acid + biofertilizer (HU + BF)]. The results revealed that the 2:2:2 intercrop fertilized with CF + BF had the highest N, P, and K concentrations for the three species. The monoculture systems with CF + BF produced the highest forage yields for ajowan (5492 kg/ha), fenugreek (3811 kg/ha), and pea (12,695 kg/ha). In addition, 2:2:2 intercrop fertilized with CF + BF produced the highest forage quality for all three species, decreasing the crude fiber, acid detergent fiber, and neutral detergent fiber contents and increasing forage ASH, dry matter intake, water‐soluble carbohydrates, and relative feed value. The 2:2:2 intercrop ratio combined with CF + BF application could be recommended to farmers as an eco‐friendly strategy (decreasing chemical fertilizer use) for improving forage productivity and quality in sustainable agricultural systems.

Narrow-leafed lupin (Lupinus angustifolius L.) is the predominant grain legume crop in southern Australia, contributing half of the total grain legume production of Australia. Its yield in Australia is hampered by a range of subsoil constraints. The adaptation of lupin genotypes to subsoil constraints may be improved by selecting for optimal root traits from new and exotic germplasm sources. We assessed root trait diversity and genetic diversity of a core collection of narrow-leafed lupin (111 accessions) using 191 Diversity Arrays Technology (DArT) markers. The genetic relationship among accessions was determined using the admixture model in STRUCTURE. Thirty-eight root-associated traits were characterized, with 21 having coefficient of variation values >0.5. Principal coordinate analysis and cluster analysis of the DArT markers revealed broad diversity among the accessions. An ad hoc statistics calculation resulted in 10 distinct populations with significant differences among and within them (P < 0.001). The mixed linear model test in TASSEL showed a significant association between all root traits and some DArT markers, with the numbers of markers associated with an individual trait ranging from 2 to 13. The percentage of phenotypic variation explained by any one marker ranged from 6.4 to 21.8%, with 15 associations explaining >10% of phenotypic variation. The genetic variation values ranged from 0 to 7994, with 23 associations having values >240. Root traits such as deeper roots and lateral root proliferation at depth would be useful for this species for improved adaptation to drier soil conditions. This study offers opportunities for discovering useful root traits that can be used to increase the yield of Australian cultivars across variable environmental conditions.

Grain quality and composition in food legumes are influenced by abiotic stresses. This review discusses the influence of abiotic stresses on grain composition and quality in food grains. Grain protein declines under salt stress due to the restricted absorption of nitrate from the soil solution. Grain phosphorus, nitrogen, and potassium contents declined whereas sodium and chloride increased. However, under drought, grain protein increased whereas the oil contents were decreased. For example, among fatty acids, oleic acid content increased; however, linoleic and/or linolenic acids were decreased under drought. Heat stress increased grain oil content whereas grain protein was decreased. Low temperature during late pod-filling reduced starch, protein, soluble sugar, fat, and fiber contents. However, an elevated CO₂ level improved omega-3 fatty acid content at the expense of omega-6 fatty acids. Crop management and improvement strategies, next generation sequencing, and gene manipulation can help improve quality of food legumes under abiotic stresses.

In the Mediterranean-type environment of south-western Australia, pod filling of chickpea occurs when net photosynthesis and nitrogen fixation is low as a result of the onset of terminal drought. Remobilisation of carbon (C) and nitrogen (N) from vegetative parts to developing seed may be an important alternative source of C and N for seed filling. The contribution of stored pre-podding C and N to seed filling was studied by labelling the vegetative tissues with the stable isotopes, 13C and 15N, prior to podding and following their subsequent movement to the seed. In ICCV88201, an advanced desi breeding line, 9% of the C and 67% of the N in the seed were derived from pre-podding C and N in well-watered plants compared with 13% of the seed C and 88% of the seed N in water-stressed plants. Furthermore, the contribution of pre-podding C and N was higher for earlier set compared with later set seeds. Pre-podding C and N were derived predominantly from the leaves with relatively little from the stems, roots, and pod walls. Genotypic variation in remobilisation ability was identified in contrasting desi (Tyson) and kabuli (Kaniva) cultivars. In well-watered Tyson, 9% of the seed C and 85% of the seed N were remobilised from vegetative tissues compared with 7% of the seed C and 62% of seed N in well-watered Kaniva. Water deficit decreased the amount of C remobilised by 3% in Tyson compared with 66% in Kaniva, whereas the total amount of N remobilised was decreased by 11% in Tyson and 48% in Kaniva. This was related to the maintenance of greater sink strength in Tyson, in which the number of filled pods was reduced by 66% in stressed plants compared with a 91% decrease in Kaniva. This indicates that better drought tolerance in desi genotypes is partly a consequence of better remobilisation and higher pod number. These studies show that C and N assimilated prior to podding can supplement the supply of current assimilates to the filling seed in both well-watered and water-stressed chickpea. Remobilisation of pre-podding N is an essential source of N for seed filling irrespective of environmental stress.

Rhizosheath carboxylates originate from plant root exudates, soil microbial activity, and soil organic matter decomposition. This review provides a comprehensive bibliometric analysis of critical discussions on the role of rhizosheath carboxylates in soil ecosystems by examining factors influencing their release, and their implications for nutrient availability, contaminant behavior, and carbon dynamics. Root exudates comprise numerous compounds, including enzymes, polysaccharides, primary metabolites such as carbohydrates, amino acids, and carboxylates, and secondary metabolites like phenols, glucosinolates, vitamins, and plant hormones. In response to biotic and abiotic stresses, soil microorganisms also release carboxylates as part of their adaptive strategies. Their release, concentration, and persistence in the rhizosheath fluctuate over time, which is influenced by various factors, including soil type, plant species, nutrient availability, microbial activity, and environmental conditions. These carboxylates play a key role in mobilizing carbon, nutrients, and contaminants, thus influencing their bioavailability to plants and microbes. While the dynamic and transient nature of these root exudates allows plants to respond to changing environmental conditions and nutrient demands by adjusting their exudation patterns, it poses significant challenges to the measurement and quantification of root exudates. This challenge can be overcome by developing techniques for the in situ measurement of root carboxylate exudation.

This new software provides a user-friendly interface to estimate stability statistics accurately for plant scientists, agronomists, and breeders who deal with large volumes of quantitative data. This software can also show ranking patterns of genotypes and describe associations among different statistics with yield performance through a heat map plot. The software is available at https://mohsenyousefian.com/stabilitysoft/.

Straw returning is an effective practice to sequester soil carbon in agricultural soils. However, the response of soil extracellular enzyme activities (EEAs) to straw returning and their linkages to soil carbon pools remain poorly understood. Here, we present a global meta-analysis on the effect of straw returning on soil hydrolytic carbon-acquiring (<em>C-acq</em>) EEAs and their relationships with soil carbon pools in agricultural ecosystems. On average, straw returning increased <em>C-acq</em> EEAs by 23.2%, soil microbial biomass carbon (MBC) content by 29.2%, and soil organic carbon (SOC) storage by 21.1%, relative to no straw returning. The effect of straw returning on MBC content and SOC storage is best explained by their positive relationships with <em>C-acq</em> EEAs: when straw returning strongly stimulates <em>C-acq</em> EEAs, MBC content and SOC storage increase; conversely, when straw returning weakly stimulates <em>C-acq</em> EEAs, MBC content and SOC storage decline. Furthermore, soil pH and straw amount best predicted the straw returning effects on <em>C-acq</em> EEAs. Our results provide the first evidence that <em>C-acq</em> EEAs are linked to soil carbon increases under straw returning in agricultural ecosystems. Incorporating the soil microbial effects of straw returning revealed here on agricultural soils into Earth system models could improve predictions of soil carbon dynamics.

Soil nitrous oxide (N2O) emissions are strongly affected by field practices, including irrigation and fertilization. This study investigated whether aerated drip irrigation (ADI) can enhance the soil environment, mitigate N2O emissions, and improve crop yields relative to conventional drip irrigation (DI). Tomato and muskmelon crops were grown in a solar greenhouse under different irrigation methods (DI and ADI) and nitrogen fertilizer rates (tomato: 0, 150, 200, and 250 kg N ha–1; muskmelon: 0, 150, and 225 kg N ha–1). The results showed that ADI increased soil temperature by 1.3–7.0 %, oxygen concentration by 1.9–3.2 %, and soil NH4+ and NO3– concentrations in the upper soil layers (0–60 cm) by 3.7–27.1 % and 3.6–51.5 % and decreased soil NH4+ and NO3– concentrations from 60 to 100 cm depth by 5.0–17.6 % and 1.9–18.9 %, relative to DI. However, ADI decreased soil moisture by 2.3–3.6 %. ADI also significantly increased soil microbial activity by 0.5–28.6 %. In addition, ADI and 150 kg N ha–1 significantly reduced yield-scaled N2O emissions (YSNES) and emission factors (EF), increasing tomato and muskmelon yields. The results of this study suggest that ADI combined with appropriate N application rates can improve soil productivity and mitigate N2O emissions.