Mitochondrial alternative oxidase pathway helps in nitrooxidative stress tolerance in germinating chickpea.

Mitochondrial alternative oxidase (AOX) is an important protein that can help in regulating reactive oxygen species and nitric oxide in plants. The role of AOX in regulation of nitro-oxidative stress in chickpea is not known. Using germinating chickpea as a model system, we investigated the role of AOX in nitro-oxidative stress tolerance. NaCl treatment was used as an inducer of nitro-oxidative stress. Treatment of germinating seeds with 150 mM NaCl led to reduced germination and radicle growth. The AOX inhibitor SHAM caused further inhibition of germination, and the AOX inducer pyruvate improved growth of the radicle under NaCl stress. Isolated mitochondria from germinated seeds under salt stress not only increased AOX capacity but also enhanced AOX protein expression. Measurement of superoxide levels revealed that AOX inhibition by SHAM can enhance superoxide levels, whereas the AOX inducer pyruvate reduced superoxide levels. Measurement of NO by gas phase chemiluminescence revealed enhanced NO generation in response to NaCl treatment. Upon NaCl treatment there was enhanced tyrosine nitration, which is an indicator of nitrosative stress response. Taken together, our results revealed that AOX induced under salinity stress in germinating chickpea can help in mitigating nitro-oxidative stress, thereby improving germination.

The potential of durum wheat-chickpea intercropping to improve the soil available phosphorus status and biomass production in a subtropical climate.

The intercropping system is a promising approach to augmenting the soil nutrient status and promoting sustainable crop production. However, it is not known whether intercropping improves the soil phosphorus (P) status in alluvial soils with low P under subtropical climates. Over two growing seasons--2019-2020 and 2020-2021--two experimental fields were employed to explore the effect of durum wheat (Dw) and chickpea (Cp) cropping systems on the soil available P. A randomized complete block design was used in this experiment, with three blocks each divided into three plots. Each plot was used for one of the following three treatments with three replications: Dw monocrop (Dw-MC), Cp monocrop (Cp-MC), and Dw + Cp intercrop (CpDw-InC), with bulk soil (BS) used as a control. A reduction in the rhizosphere soil pH (-0.44 and -0.11 unit) was observed in the (Cp-MC) and (CpDw-InC) treatments over BS, occurring concomitantly with a significant increase in available P in the rhizosphere soil of around 28.45% for CpDw-InC and 24.9% for Cp-MC over BS. Conversely, the rhizosphere soil pH was significantly higher (+0.12 units) in the Dw-MC treatments. In addition, intercropping enhanced the soil microbial biomass P, with strong positive correlations observed between the biomass P and available P in the Cp-MC treatment, whereas this correlation was negative in the CpDw-InC and Dw-MC treatments. These findings suggested that Cp intercropped with Dw could be a viable approach in enhancing the available P through improved pH variation and biomass P when cultivated on alluvial soil under a subtropical climate.

Responses of soil enzymatic activities and microbial biomass phosphorus to improve nutrient accumulation abilities in leguminous species.

Fertilizers application are widely used to get a higher yield in agricultural fields. Nutrient management can be improved by cultivating leguminous species in order to obtain a better understanding of the mechanisms that increase the amount of available phosphorus (P) and potassium (K) through fertilizer treatments. A pot experiment was conducted to identify the leguminous species (i.e., chickpea and pea) under various fertilizer treatments. Experimental design is as follows: T0 (control: no fertilizer was applied), T1: P applied at the level of (90 kg ha-1), T2: (K applied at the level of 90 kg ha-1), and T3: (PK applied both at 90 kg ha-1). All fertilizer treatments significantly (p < 0.05) improved the nutrient accumulation abilities and enzymes activities. The T3 treatment showed highest N uptake in chickpea was 37.0%, compared to T0. While T3 developed greater N uptake in pea by 151.4% than the control. However, T3 treatment also increased microbial biomass phosphorus in both species i.e., 95.7% and 81.5% in chickpeas and peas, respectively, compared to T0 treatment. In chickpeas, T1 treatment stimulated NAGase activities by 52.4%, and T2 developed URase activities by 50.1% higher than control. In contrast, T3 treatment enhanced both BGase and Phase enzyme activities, i.e., 55.8% and 33.9%, respectively, compared to the T0 treatment. Only the T3 treatment improved the activities of enzymes in the pea species (i.e., BGase was 149.7%, URase was 111.9%, Phase was 81.1%, and NAGase was 70.0%) compared to the control. Therefore, adding combined P and K fertilizer applications to the soil can increase the activity of enzymes in both legume species, and changes in microbial biomass P and soil nutrient availability make it easier for plants to uptake the nutrients.

Physio-biochemical responses and crop performance analysis in chickpea upon botanical priming.

Chickpea is a highly nutritious protein-rich source and one of the major crops to alleviate global malnutrition, but poor seed quality affects its productivity. Seed quality is essential for better crop establishment and higher yields, particularly in the uncertain climate change. The present study investigated the impact of botanical priming versus hydropriming and bavistin seed treatment on chickpea seeds. A detailed physiological (germination percentage, root and shoot length, vigour index) and biochemical (amylase, protease, dehydrogenase, phytase, and lipid peroxidation) analysis was carried out in order to assess the effect of priming treatments. Turmeric-primed seeds showed better germination rate (94.5%), seedling length, enzyme activity, and lower malondialdehyde (MDA) content. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed the expression of minor polypeptides of albumin and globulin in the primed seeds. Moreover, field experiments indicated increased crop growth, vigour, days to 50% flowering, yield and its attributing traits in turmeric-primed seeds. Botanical priming can increase chickpea yield by up to 16% over the control group. This low-cost and eco-friendly technique enhances seed and crop performance, making it a powerful tool for augmenting chickpea growth. Therefore, chickpea growers must adopt botanical priming techniques to enhance the quality of seed and crop performance. Moreover, this approach is environmentally sustainable and can help conserve natural resources in the long term. Therefore, this new approach must be widely adopted across the agricultural industry to ensure sustainable and profitable farming practices.

MicroRNA164e suppresses NAC100 transcription factor-mediated synthesis of seed storage proteins in chickpea.

Development of protein-enriched chickpea varieties necessitates an understanding of specific genes and key regulatory circuits that govern the synthesis of seed storage proteins (SSPs). Here, we demonstrated the novel involvement of Ca-miR164e-CaNAC100 in regulating SSP synthesis in chickpea. Ca-miRNA164e was significantly decreased during seed maturation, especially in high-protein accessions. The miRNA was found to directly target the transactivation conferring C-terminal region of a nuclear-localized transcription factor, CaNAC100 as revealed using RNA ligase-mediated-rapid amplification of cDNA ends and target mimic assays. The functional role of CaNAC100 was demonstrated through seed-specific overexpression (NACOE) resulting in significantly augmented seed protein content (SPC) consequential to increased SSP transcription. Further, NACOE lines displayed conspicuously enhanced seed weight but reduced numbers and yield. Conversely, a downregulation of CaNAC100 and SSP transcripts was evident in seed-specific overexpression lines of Ca-miR164e that culminated in significantly lowered SPC. CaNAC100 was additionally demonstrated to transactivate the SSP-encoding genes by directly binding to their promoters as demonstrated using electrophoretic mobility shift and dual-luciferase reporter assays. Taken together, our study for the first time established a distinct role of CaNAC100 in positively influencing SSP synthesis and its critical regulation by CamiR164e, thereby serving as an understanding that can be utilized for developing SPC-rich chickpea varieties.

Effect of drought stress on the expression pattern of genes involved in ABA biosynthesis in Desi-type chickpea (Cicer arietinum L.).

BACKGROUND: The behavior of Abscisic acid (ABA) as a stress phytohormone may be involved in mechanisms leading to tolerance and survival in adverse environmental conditions such as drought stress. METHODS: Here, we evaluated ABA-mediated responses at physio-biochemical and molecular levels in drought-stressed seedlings of two different Desi-type chickpea genotypes (10 as a tolerant genotype and 247 as a sensitive one). RESULTS: Under drought stress, two chickpea genotypes showed a decrease in their relative water content (RWC), and the intense decrease was related to the sensitive genotype (73.9%) in severe stress. Hydrogen peroxide (H2O2) and malondialdehyde (MDA) concomitant with the severity of stress increased in genotypes and the higher increase was in the sensitive genotype (5.8-fold and 3.43-fold, respectively). In the tolerant genotype, the enhanced accumulation of total phenolic content (1.75-fold) and radical scavenging action, based on 1,1-diphenyl-2-picrylhydrazyl test (DPPH), (1.69-fold) were simultaneous with ABA accumulation (1.53-fold). In the tolerant genotype, transcriptional analysis presented upregulation of Zeaxanthin epoxidase (ZEP) (1.35-fold), 9-cis-epoxycarotenoid dioxygenase (NCED) (5.16-fold), and Abscisic aldehyde oxidase (AAO) (1.52-fold compared to control conditions) genes in severe stress in comparison with mild stress. The sensitive genotype had a declining trend in total chlorophyll (up to 70%) and carotenoid contents (36%). The main conclusion to be drawn from this investigation is that ABA with its regulatory effects can affect drought tolerance mechanisms to alleviate adverse effects of unsatisfactory environmental conditions. CONCLUSIONS: In this paper, we tried to indicate that drought stress induces overexpression of genes triggering ABA-mediated drought responses simultaneously in two genotypes while more increment expression was related to the tolerant genotype. At first thought, it seems that the tolerant genotype compared to the sensitive genotype has a genetically inherent ability to cope with and drop adverse effects of drought stress through over-accumulation of ABA as drought.

Role of calcium signaling in cadmium stress mitigation by indol-3-acetic acid and gibberellin in chickpea seedlings.

Given the adverse impacts of heavy metals on plant development and physiological processes, the present research investigated the protective role of indole-3-acetic acid (IAA) and gibberellic acid (GA3) against cadmium (Cd)-induced injury in chickpea seedlings. Therefore, seeds germinated for 6 days in a medium containing 200 µM Cd alone or combined with 10 µM GA3 or 10 µM IAA. Both GA3 and IAA mitigated Cd-imposed growth delays in roots and shoots (80% and 50% increase in root and shoot length, respectively). This beneficial effect was accompanied by a significant reduction in Cd2+ accumulation in both roots (74% for IAA and 38% for GA3) and shoots (68% and 35%, respectively). Furthermore, these phytohormones restored the cellular redox state by reducing the activity of NADPH oxidase and downregulating the transcription level of RbohF and RbohD genes. Likewise, hydrogen peroxide contents were reduced by GA3 and IAA supply. Additionally, GA3 and IAA countered the Cd-induced reduction in total phenols, flavonoids, and reducing sugars in both roots and shoots. The exogenous effectors enhanced the activities of catalase, ascorbate peroxidase, and thioredoxin, as well as the corresponding gene expressions. Interestingly, adding GA3 and IAA to the Cd-contaminated germination media corrected the level of calcium (Ca2+) ion within seedling tissues. This effect coincided with the upregulation of key genes associated with stress sensing and signal transduction, including auxin-binding protein (ABP19a), mitogen-activated protein kinase (MAPK2), calcium-dependent protein kinase (CDPK1), and calmodulin (CaM). Overall, the current results suggest that GA3 and IAA sustain the Ca2+ signaling pathway, resulting in metal phytotoxicity relief. Amendment of agricultural soils contaminated with heavy metals with GA3 or IAA could represent an effective practice to improve crop yield.

Genome-wide analysis and expression divergence of protein disulfide isomerase (PDI) gene family members in chickpea (Cicer arietinum) under salt stress.

Chickpea (Cicer arietinum ) is a grain crop that is an important source of protein, vitamins, carbohydrates and minerals. It is highly sensitive to salt stress, and salt damage to cellular homeostasis and protein folding affects production. Plants have several mechanisms to prevent cellular damages under abiotic stresses, such as proteins in the endoplasmic reticulum (protein isulfide somerases (PDIs) and PDI-like proteins), which help prevent the build-up of mis-folded proteins that are damaged under abiotic stresses. In this study, we completed initial comprehensive genome-wide analysis of the chickpea PDI gene family. We found eight PDI genes are distributed on six out of eight chromosomes. Two pairs of paralogous genes were found to have segmental duplications. The phylogenetic analysis showed that the PDI s have a high degree of homology in C. arietinum, Cicer reticulatum, Lens culinaris, Phaseolus acutifolius, Pisum sativum and Oryza sativa . The gene structure analysis displayed that CaPDI1-CaPDI8 have 9-12 exons except for CaPDI5 , which has 25 exons. Subcellular localisation indicated accumulation of CaPDIs in endoplasmic reticulum. Protein-conserved motifs and domain analysis demonstrated that thioredoxin domains of PDI family is present in all CaPDIs. CaPDI proteins have strong protein-protein interaction. In silico expression analysis showed that four out of eight PDI genes (CPDI2, CaPDI6, CaPDI7 and CaPDI8 ) were expressed under salt stress. Of these, expression of CaPDI2 and CaPDI8 was the highest. This work indicated that PDI genes are involved in salt stress tolerance in chickpea and the CaPDIs may be further studied for their role of inducing salt tolerance.

Isoflavones isolated from chickpea sprouts alleviate ovariectomy-induced osteoporosis in rats by dual regulation of bone remodeling.

Osteoporosis is a common systemic skeletal disease and a predominant underlying factor in the increased occurrence of fractures. The structure of isoflavones resembles that of estrogen and can confer similar but weaker effects. This study investigated the potential inhibitory effects of isoflavones from chickpea sprouts (ICS) on ovariectomy (OVX)-induced osteoporosis in vitro and in vivo. Notably, we found that ICS treatment could attenuate bone loss and improve trabecular microarchitecture and biomechanical properties of the fourth lumbar vertebra in OVX-induced osteoporotic rats and could also inhibit the development of a hyperosteometabolic state in this model. The osteogenic differentiation of bone marrow stem cells (BMSCs) was significantly enhanced by ICS intervention in vitro, and we confirmed that estrogen receptor α signaling was required for this increased osteogenic differentiation. Additionally, ICS has been shown to inhibit bone resorption via ERa modulation of the OPG/RANKL pathway. RANKL-induced osteoclastogenesis was reduced under ICS treatment, supporting that NF-κB signaling was inhibited by ICS. Thus, ICS attenuates osteoporosis progression by promoting osteogenic differentiation and inhibiting osteoclastic resorption. These results support the further exploration and development of ICS as a pharmacological agent for the treatment and prevention of osteoporosis.

Functional allele of a MATE gene selected during domestication modulates seed color in chickpea.

Seed color is one of the key target traits of domestication and artificial selection in chickpeas due to its implications on consumer preference and market value. The complex seed color trait has been well dissected in several crop species; however, the genetic mechanism underlying seed color variation in chickpea remains poorly understood. Here, we employed an integrated genomics strategy involving QTL mapping, high-density mapping, map-based cloning, association analysis, and molecular haplotyping in an inter-specific RIL mapping population, association panel, wild accessions, and introgression lines (ILs) of Cicer gene pool. This delineated a MATE gene, CaMATE23, encoding a Transparent Testa (TT) and its natural allele (8-bp insertion) and haplotype underlying a major QTL governing seed color on chickpea chromosome 4. Signatures of selective sweep and a strong purifying selection reflected that CaMATE23, especially its 8-bp insertion natural allelic variant, underwent selection during chickpea domestication. Functional investigations revealed that the 8-bp insertion containing the third cis-regulatory RY-motif element in the CaMATE23 promoter is critical for enhanced binding of CaFUSCA3 transcription factor, a key regulator of seed development and flavonoid biosynthesis, thereby affecting CaMATE23 expression and proanthocyanidin (PA) accumulation in the seed coat to impart varied seed color in chickpea. Consequently, overexpression of CaMATE23 in Arabidopsis tt12 mutant partially restored the seed color phenotype to brown pigmentation, ascertaining its functional role in PA accumulation in the seed coat. These findings shed new light on the seed color regulation and evolutionary history, and highlight the transcriptional regulation of CaMATE23 by CaFUSCA3 in modulating seed color in chickpea. The functionally relevant InDel variation, natural allele, and haplotype from CaMATE23 are vital for translational genomic research, including marker-assisted breeding, for developing chickpea cultivars with desirable seed color that appeal to consumers and meet global market demand.

Zinc oxide nanoparticles alleviate chromium-induced oxidative stress by modulating physio-biochemical aspects and organic acids in chickpea (Cicer arietinum L.).

Extensive chromium (Cr) release into water and soil severely impairs crop productivity worldwide. Nanoparticle (NP) technology has shown potential for reducing heavy metal toxicity and improving plant physicochemical profiles. Herein, we investigated the effects of exogenous zinc oxide NPs (ZnO-NPs) on alleviating Cr stress in Cr-sensitive and tolerant chickpea genotypes. Hydroponically grown chickpea plants were exposed to Cr stress (0 and 120 µM) and ZnO-NPs (25 µM, 20 nm size) twice at a 7-day interval. Cr exposure reduced physiochemical profiles, ion content, cell viability, and gas exchange parameters, and it increased organic acid exudate accumulation in roots and the Cr content in the roots and leaves of the plants. However, ZnO-NP application significantly increased plant growth, enzymatic activities, proline, total soluble sugar, and protein and gas exchange parameters and reduced malondialdehyde and hydrogen peroxide levels, Cr content in roots, and organic acid presence to improve root cell viability. This study provides new insights into the role of ZnO-NPs in reducing oxidative stress along with Cr accumulation and mobility due to low levels of organic acids in chickpea roots. Notably, the Cr-tolerant genotype exhibited more pronounced alleviation of Cr stress by ZnO-NPs. These findings highlight the potential of ZnO-NP in regulating plant growth, reducing Cr accumulation, and promoting sustainable agricultural development.

Multifarious Potential of Biopolymer-Producing Bacillus subtilis NJ14 for Plant Growth Promotion and Stress Tolerance in Solanum lycopercicum L. and Cicer arietinum L: A Way Toward Sustainable Agriculture.

Diverse practices implementing biopolymer-producing bacteria have been examined in various domains lately. PHAs are among the major biopolymers whose relevance of PHA-producing bacteria in the field of crop improvement is one of the radical unexplored aspects in the field of agriculture. Prolonging shelf life is one serious issue hindering the establishment of biofertilizers. Studies support that PHA can help bacteria survive stressed conditions by providing energy. Therefore, PHA-producing bacteria with Plant Growth-Promoting ability can alter the existing problem of short shelf life in biofertilizers. In the present study, Bacillus subtilis NJ14 was isolated from the soil. It was explored to understand the ability of the strain to produce PHA and augment growth in Solanum lycopersicum and Cicer arietinum. NJ14 strain improved the root and shoot length of both plants significantly. The root and shoot length of S. lycopersicum was increased by 3.49 and 0.41 cm, respectively. Similarly, C. arietinum showed a 9.55 and 8.24 cm increase in root and shoot length, respectively. The strain also exhibited halotolerant activity (up to 10%), metal tolerance to lead (up to 1000 µg/mL) and mercury (up to 100 µg/mL), indicating that the NJ14 strain can be an ideal candidate for a potent biofertilizer.

Genome-wide analysis of Glutathione peroxidase (GPX) gene family in Chickpea (Cicer arietinum L.) under salinity stress.

Chickpea is the second most widely grown legume in the world. Its cultivation is highly affected by saline soils. Salt stress damages its all growth stages from germination to maturity. It has a huge genetic diversity containing adaptation loci that can help produce salt-tolerant cultivars. The glutathione peroxidase (GPX) gene family plays an important role in regulating plant response to abiotic stimuli and protects cells from oxidative damage. In current research, the role of GPX genes is studied for inducing salt tolerance in chickpea. This study identifies the GPX gene family in Cicer arietinum. In response to the NaCl stress, the gene expression profiles of CaGPX3 were examined using real-time qRT-PCR. The results of phylogenetic analysis show that CaGPX genes have an evolutionary relationship with monocots, dicots, chlorophytes, and angiosperms. Gene structure analysis showed that CaGPX3, CaGPX4, and CaGPX5 have six, CaGPX2 has five, and CaGPX1 contains 9 exons. According to the Ka and Ks analysis chickpea has one pair of duplicated genes of GPX and the duplication was tandem with negative (purifying) selection Ka < Ks (<1). In-silico gene expression analysis revealed that CaGPX3 is a salt stress-responsive gene among all other five GPX members in chickpea. The qRT-PCR results showed that the CaGPX3 gene expression was co-ordinately regulated under salt stress conditions, confirming CaGPX3's key involvement in salt tolerance.

Metabolomic insights into the effect of chickpea protein hydrolysate on the freeze-thaw tolerance of industrial yeasts.

The use of frozen dough is an intensive food-processing practice that contributes to the development of chain operations in the bakery industry. However, the fermentation activity of yeasts in frozen dough can be severely damaged by freeze-thaw stress, thereby degrading the final bread quality. In this study, chickpea protein hydrolysate significantly improved the quality of steamed bread made from frozen dough while enhancing the yeast survival rate and maintaining yeast cell structural integrity under freeze-thaw stress. The mechanism underlying this protective role of chickpea protein hydrolysate was further investigated by untargeted metabolomics analysis, which suggested that chickpea protein hydrolysate altered the intracellular metabolites associated with central carbon metabolism, amino acid synthesis, and lipid metabolism to improve yeast cell freeze-thaw tolerance. Therefore, chickpea protein hydrolysate is a promising natural antifreeze component for yeast cryopreservation in the frozen dough industry.

Plant growth promoting rhizobacterium Bacillus sp. BSE01 alleviates salt toxicity in chickpea (Cicer arietinum L.) by conserving ionic, osmotic, redox and hormonal homeostasis.

Soil salinity leading to sodium toxicity is developing into a massive challenge for agricultural productivity globally, inducing osmotic, ionic, and redox imbalances in plants. Considering the predicted increase in salinization risk with the ongoing climate change, applying plant growth-promoting rhizobacteria (PGPR) is an environmentally safe method for augmenting plant salinity tolerance. The present study examined the role of halotolerant Bacillus sp. BSE01 as a promising biostimulant for improving salt stress endurance in chickpea. Application of PGPR significantly increased the plant height, relative water content, and chlorophyll content of chickpea under both non-stressed and salt stress conditions. The PGPR-mediated tolerance towards salt stress was accomplished by the modulation of hormonal signaling and conservation of cellular ionic, osmotic, redox homeostasis. With salinity stress, the PGPR-treated plants significantly increased the indole-3-acetic acid and gibberellic acid contents more than the non-treated plants. Furthermore, the PGPR-inoculated plants maintained lower 1-aminocyclopropane-1-carboxylic acid and abscisic acid contents under salt treatment. The PGPR-inoculated chickpea plants also exhibited a decreased NADPH oxidase activity with reduced production of reactive oxygen species compared to the non-inoculated plants. Additionally, PGPR treatment led to increased antioxidant enzyme activities in chickpea under saline conditions, facilitating the reactive nitrogen and oxygen species detoxification, thereby limiting the nitro-oxidative damage. Following salinity stress, enhanced K+ /Na+ ratio and proline content were noted in the PGPR-inoculated chickpea plants. Therefore, Bacillus sp. BSE01, being an effective PGPR and salinity stress reducer, can further be considered to develop a bioinoculant for sustainable chickpea production under saline environments.

Multifarious Plant Growth-Promoting Rhizobacterium Enterobacter sp. CM94-Mediated Systemic Tolerance and Growth Promotion of Chickpea (Cicer arietinum L.) under Salinity Stress.

BACKGROUND: Chickpea is one of the most important leguminous crops and its productivity is significantly affected by salinity stress. The use of ecofriendly, salt-tolerant, plant growth-promoting rhizobacteria (PGPR) as a bioinoculant can be very effective in mitigating salinity stress in crop plants. In the present study, we explored, characterized, and evaluated a potential PGPR isolate for improving chickpea growth under salt stress. METHODS: A potential PGPR was isolated from rhizospheric soils of chickpea plants grown in the salt-affected area of eastern Uttar Pradesh, India. The isolate was screened for salt tolerance and characterized for its metabolic potential and different plant growth-promoting attributes. Further, the potential of the isolate to promote chickpea growth under different salt concentrations was determined by a greenhouse experiment. RESULTS: A rhizobacteria isolate, CM94, which could tolerate a NaCl concentration of up to 8% was selected for this study. Based on the BIOLOG carbon source utilization, isolate CM94 was metabolically versatile and able to produce multiple plant growth-promoting attributes, such as indole acetic acid, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, siderophore, hydrogen cyanide (HCN), and ammonia as well as solubilized phosphate. A polyphasic approach involving the analysis of fatty acid methyl ester (FAME) and 16S rRNA gene sequencing confirmed the identity of the isolate as Enterobacter sp. The results of greenhouse experiments revealed that isolate CM94 inoculation significantly enhanced the shoot length, root length, and fresh and dry weight of chickpea plants, under variable salinity stress. In addition, inoculation improved the chlorophyll, proline, sugar, and protein content in the tissues of the plant, while lowering lipid peroxidation. Furthermore, isolate CM94 reduced oxidative stress by enhancing the enzymatic activities of superoxide dismutase, catalase, and peroxidase compared to in the respective uninoculated plants. CONCLUSIONS: Overall, the results suggested that using Enterobacter sp. CM94 could significantly mitigate salinity stress and enhance chickpea growth under saline conditions. Such studies will be helpful in identifying efficient microorganisms to alleviate salinity stress, which in turn will help, to devise ecofriendly microbial technologies.

Genome wide identification and characterization of the amino acid transporter (AAT) genes regulating seed protein content in chickpea (Cicer arietinum L.).

Amino acid transporters (AATs), besides, being a crucial component for nutrient partitioning system are also vital for growth and development of the plants and stress resilience. In order to understand the role of AAT genes in seed quality proteins, a comprehensive analysis of AAT gene family was carried out in chickpea leading to identification of 109 AAT genes, representing 10 subfamilies with random distribution across the chickpea genome. Several important stress responsive cis-regulatory elements like Myb, ABRE, ERE were detected in the promoter region of these CaAAT genes. Most of the genes belonging to the same sub-families shared the intron-exon distribution pattern owing to their conserved nature. Random distribution of these CaAAT genes was observed on plasma membrane, vacuolar membrane, Endoplasmic reticulum and Golgi membranes, which may be associated to distinct biochemical pathways. In total 92 out 109 CaAAT genes arise as result of duplication, among which segmental duplication was more prominent over tandem duplication. As expected, the phylogenetic tree was divided into 2 major clades, and further sub-divided into different sub-families. Among the 109 CaAAT genes, 25 were found to be interacting with 25 miRNAs, many miRNAs like miR156, miR159 and miR164 were interacting only with single AAT genes. Tissues specific expression pattern of many CaAAT genes was observed like CaAAP7 and CaAVT18 in nodules, CaAAP17, CaAVT5 and CaCAT9 in vegetative tissues while CaCAT10 and CaAAP23 in seed related tissues as per the expression analysis. Mature seed transcriptome data revealed that genotypes having high protein content (ICC 8397, ICC 13461) showed low CaAATs expression as compared to the genotypes having low protein content (FG 212, BG 3054). Amino acid profiling of these genotypes revealed a significant difference in amount of essential and non-essential amino acids, probably due to differential expression of CaAATs. Thus, the present study provides insights into the biological role of AAT genes in chickpea, which will facilitate their functional characterization and role in various developmental stages, stress responses and involvement in nutritional quality enhancement.

Genetic mapping and transcriptome profiling of a chickpea (Cicer arietinum L.) mutant identifies a novel locus (CaEl) regulating organ size and early vigor.

Chickpea is among the top three legumes produced and consumed worldwide. Early plant vigor, characterized by good germination and rapid seedling growth, is an important agronomic trait in many crops including chickpea, and shows a positive correlation with seed size. In this study, we report a gamma-ray-induced chickpea mutant with a larger organ and seed size. The mutant (elm) exhibits increased early vigor and contains higher proline that contributes to a better tolerance under salt stress at germination, seedling, and early vegetative phase. The trait is governed as monogenic recessive, with wild-type allele being incompletely dominant over the mutant. Genetic mapping of this locus (CaEl) identified it as a previously uncharacterized gene (101503252) in chromosome 1 of the chickpea genome. There is a deletion of this gene in the mutant with a complete loss of expression. In silico analysis suggests that the gene is present as a single copy in chickpea and related legumes of the galegoid clade. In the mutant, cell division and expansion are affected. Transcriptome profiling identified differentially regulated transcripts related to cell division, expansion, cell wall organization, and metabolism in the mutant. The mutant can be exploited in chickpea breeding programs for increasing plant vigor and seed size.

In-depth analysis of the xanthine oxidase inhibitors of Cicer arietinum L.-based receptor-ligand affinity coupled with complex chromatography.

INTRODUCTION: Cicer arietinum L. is the choice of health food for people with diabetes, hypertension, and hyperlipidemia. As an essential source of high-nutrition legumes, it is also an important source of dietary isoflavones. OBJECTIVES: In order to improve the preparation efficiency of natural plants, a rapid biological activity screening and preparation of xanthine oxidase inhibitors from C. arietinum L. was established. METHODS: Xanthine oxidase (XOD) inhibitors were rapidly screened using ultrafiltration liquid chromatography-mass spectrometry (UF-LC-MS) based on receptor-ligand affinity. The change in XOD activity was evaluated by enzymatic reaction kinetics measurement. The potential bioactive compounds were verified through molecular docking. In addition, the biological activity of ligands screened was separated and purified by complex chromatography. The structures of the compounds were identified by nuclear magnetic resonance spectroscopy. RESULTS: Three active ingredients, namely daidzin, daidzein, calycosin with XOD binding affinities were identified and isolated from the raw plant materials via semi-preparative high-performance liquid chromatography (HPLC), 0-60 min, 5-50% B and countercurrent chromatography (CCC) (ethyl acetate/acetic acid/water [5:0.8:10, v/v/v]). CONCLUSION: This study will help to elucidate the mechanisms of action of natural plants of interest at the molecular level and could also provide more opportunities for the discovery and development of new nutritional value from other natural resources.

Intercropping Sedum alfredii Hance and Cicer arietinum L. does not present a suitable land use pattern for multi-metal-polluted soil.

Intercropping of specific accumulators with industrial crops is used in moderately metal contaminated agricultural land. The distribution characteristics and environmental risks of non-accumulated ions in intercropping fields have rarely been reported. This study analyzed dissolved organic matter (DOM) fractionation and metal chemical forms to investigate the bioavailability, transformation, and uptake of non-hyperaccumulated metals in different cultivation patterns of a Cd hyperaccumulator (Sedum alfredii Hance) and a commercial crop (Cicer arietinum L.). The study focused on the distribution and transformation of heavy metals, with a particular emphasis on the role of DOM in intercropping. The contents of DOM in the rhizosphere soils of the Cd hyperaccumulator monoculture and the intercropping field were obviously greater than the DOM concentration in the commercial crop monoculture. The content of soluble Cd was significantly lower in the former two planting patterns than in the latter. In contrast, soluble Pb and Cu exhibited opposite content characteristics. In addition, the metal extraction ability of DOM extracted from the C. arietinum monoculture was lower than those from the Cd hyperaccumulator monoculture and the intercropping field. The concentrations of Cd in both below-ground and aerial parts of C. arietinum intercropping were significantly lower than those in its monoculture, since S. alfredii depleted soil Cd. Contrastingly, the contents of Cu and Pb in C. arietinum harvested from intercropping were significantly greater than those in its monoculture because the intercropped Cd hyperaccumulator activated Cu and Pb by changing soil DOM content and fractionations without absorbing them. The findings provide valuable insights into the use of intercropping to remediate moderately metal-contaminated agricultural land and highlight the potential risks associated with intercropping in multi-metal-contaminated fields.