Resistant Chickpea Research Articles

Genetic resources and genes/QTLs for gram pod borer (Helicoverpa armigera Hübner) resistance in chickpea from the Western Himalayas.

Helicoverpa armigera (also known as gram pod borer) is a serious threat to chickpea production in the world. A set of 173 chickpea genotypes were evaluated for H. armigera resistance, including mean larval population (MLP), percentage pod damage (PPD), and pest resistance (PR) for 2 consecutive years (year 2020 and 2021). The same core set was also genotyped with 50K AxiomCicerSNP Array. The trait data and 50,000 single nucleotide polymorphism genotypic data were used together to work out marker-trait associations (MTAs) using different genome-wide association studies models. For MLP, a total of 53 MTAs were identified, including 25 MTAs in year 2020 and 28 MTAs in year 2021. A set of three MTAs was found common in both environments. For PPD, two MTAs in year 2020 and five MTAs in year 2021 were identified. A set of two MTAs were common in both environments. Similarly, for PR, only two MTAs common in both environments were identified. Interestingly, a common MTA (Affx_123255526) on chromosome 2 (Ca2) was found to be associated with all the three component traits (MLP, PPD, and PR) of pod borer resistance in chickpea. Further, we report key genes that encode SCAMPs (that facilitates the secretion of defense-related molecules), quinone oxidoreductase (enables the production of reactive oxygen species that promotes diapause of gram pod borer), and NB-LRR proteins that have been implicated in plant defense against H. armigera. The resistant chickpea genotypes, MTAs, and key genes reported in the present study may prove useful in the future for developing pod borer-resistant chickpea varieties.

Identification of Fusarium spp. Associated with Chickpea Root Rot in Montana

Root rot caused by Fusarium spp. is a significant issue in the chickpea-growing regions of Montana. The specific Fusarium species responsible for the disease and their prevalence remain uncertain. A survey was conducted in 2020 and 2021 to identify Montana’s Fusarium species associated with chickpea. Four hundred and twenty-six Fusarium isolates were recovered from symptomatic chickpea roots across ten counties in the state. Isolates were identified by comparing translation elongation factor 1-α (TEF1-α) sequences in the FUSARIUM-ID database. Among the recovered isolates, Fusarium oxysporum was the most prevalent species (33%), followed by F. acuminatum (21%), F. avenaceum (15%), F. redolens (14%), F. culmorum (6%), F. sporotrichioides (6%), Neocosmospora solani (6%), F. equiseti (2%), F. torulosum (0.9%), F. gamsii (0.8%), F. proliferatum (0.2%), F. pseudograminearum (0.2%), and F. brachygibbosum (0.1%). The aggressiveness of a subset of 51 isolates representing various Fusarium spp. was tested on chickpea cv. ‘CDC Frontier’. A non-parametric variance analysis conducted on disease severity ranks indicated that F. avenaceum isolates were highly aggressive. This study reports for the first time that F. gamsii, F. proliferatum and F. brachygibbosum are causal agents of root rot in chickpea in the United States. This knowledge is invaluable for making informed decisions regarding crop rotation, disease management, and developing resistant chickpea varieties against economically significant Fusarium pathogens.

Expression analysis and characterization of resistance (R) genes in contrasting Fusarium wilt resistant chickpea genotypes

Fusarium wilt is one of the most notorious diseases of crop plants. This disease leads to huge crop losses in chickpea with substantial monetary value worldwide. The objective of the current study was to characterise Fusarium oxysporum f. sp. cicris (Foc), the causal agent of chickpea wilt, on morphological basis followed by the assessment of resistance of thirty chickpea germplasm accessions to Foc in a pot experiment. The second objective of this research was to study gene expression and characterisation of specific resistance (R) genes in different Fusarium wilt-resistant chickpea genotypes. The morphological identification and characterization of Foc was done by culturing the fungus potato dextrose agar (PDA) medium. Fusarium wild resistance was assessed by challenging 30 chickpea genotypes to artificial inoculum of Foc by using a pre-defined disease rating scale. Different resistance levels were showed by different chickpea genotypes ranging from highly resistant to highly susceptible. Two accessions demonstrated resistance, 15 were moderately resistant and the rest of the genotypes were moderately susceptible to susceptible. The in-silico expression analysis of R genes showed that two R genes, LOC101499430 and LOC101499568 were upregulated in chickpea roots, indicating their probable role in Fusarium wilt resistance. The genes were further assessed for their expression in response to Fusarium inoculation in contrasting Fusarium wilt resistant and susceptible chickpea genotypes. The resistant genotypes showed significantly higher expression levels of the selected R genes in comparison with susceptible genotypes. This study provides valuable insights into evaluating chickpea germplasm for Fusarium wilt resistance and identification of candidate resistance genes which could be employed for enhancement of Fusarium wilt resistance in chickpea.

Genetic Analysis of Partially Resistant and Susceptible Chickpea Cultivars in Response to Ascochyta rabiei Infection.

The molecular mechanism involved in chickpea (Cicer arietinum L.) resistance to the necrotrophic fungal pathogen Ascochyta rabiei is not well documented. A. rabiei infection can cause severe damage in chickpea, resulting in significant economic losses. Understanding the resistance mechanism against ascochyta blight can help to define strategies to develop resistant cultivars. In this study, differentially expressed genes from two partially resistant cultivars (CDC Corinne and CDC Luna) and a susceptible cultivar (ICCV 96029) to ascochyta blight were identified in the early stages (24, 48 and 72 h) of A. rabiei infection using RNA-seq. Altogether, 3073 genes were differentially expressed in response to A. rabiei infection across different time points and cultivars. A larger number of differentially expressed genes (DEGs) were found in CDC Corinne and CDC Luna than in ICCV 96029. Various transcription factors including ERF, WRKY, bHLH and MYB were differentially expressed in response to A. rabiei infection. Genes involved in pathogen detection and immune signalings such as receptor-like kinases (RLKs), Leucine-Rich Repeat (LRR)-RLKs, and genes associated with the post-infection defence response were differentially expressed among the cultivars. GO functional enrichment and pathway analysis of the DEGs suggested that the biological processes such as metabolic process, response to stimulus and catalytic activity were overrepresented in both resistant and susceptible chickpea cultivars. The expression patterns of eight randomly selected genes revealed by RNA-seq were confirmed by quantitative PCR (qPCR) analysis. The results provide insights into the complex molecular mechanism of the chickpea defence in response to the A. rabiei infection.

Metabolite profiling of chickpea (Cicer arietinum) in response to necrotrophic fungus Ascochyta rabiei.

Ascochyta blight (AB) caused by the necrotrophic fungus Ascochyta rabiei is one of the most significant diseases that limit the production of chickpea. Understanding the metabolic mechanisms underlying chickpea-A.rabiei interactions will provide important clues to develop novel approaches to manage this disease. We performed metabolite profiling of the aerial tissue (leaf and stem) of two chickpea accessions comprising a moderately resistant breeding line (CICA1841) and a highly susceptible cultivar (Kyabra) in response to one of the highly aggressive Australian A. rabiei isolates TR9571 via non-targeted metabolomics analysis using liquid chromatography-mass spectrometry. The results revealed resistance and susceptibility-associated constitutive metabolites for example the moderately resistant breeding line had a higher mass abundance of ferulic acid while the levels of catechins, phthalic acid, and nicotinic acid were high in the susceptible cultivar. Further, the host-pathogen interaction resulted in the altered levels of various metabolites (induced and suppressed), especially in the susceptible cultivar revealing a possible reason for susceptibility against A.r abiei. Noticeably, the mass abundance of salicylic acid was induced in the aerial tissue of the susceptible cultivar after fungus colonization, while methyl jasmonate (MeJA) was suppressed, elucidating the key role of phytohormones in chickpea-A. rabiei interaction. Many differential metabolites in flavonoid biosynthesis, phenylalanine, Aminoacyl-tRNA biosynthesis, pentose and glucuronate interconversions, arginine biosynthesis, valine, leucine, and isoleucine biosynthesis, and alanine, aspartate, and glutamate metabolism pathways were up- and down-regulated showing the involvement of these metabolic pathways in chickpea-A. rabiei interaction. Taken together, this study highlights the chickpea - A. rabiei interaction at a metabolite level and shows how A. rabiei differentially alters the metabolite profile of moderately resistant and susceptible chickpea accessions and is probably exploiting the chickpea defense pathways in its favour.

Noor-2019: A High Yielding and Wilt Resistant Chickpea Kabuli (Cicer arietinum L.) Variety Developed through Introgression Breeding

Noor-2019: A High Yielding and Wilt Resistant Chickpea Kabuli (Cicer arietinum L.) Variety Developed through Introgression Breeding

Expression comparisons of defense-related genes in resistant and susceptible chickpea cultivars in response to Ascochyta rabiei

Ascochyta blight caused by Ascochyta rabiei is a destructive disease affecting chickpea crops worldwide. Numerous studies have sought to identify resistance genes involved in the defense response against Ascochyta blight, but the function of potential resistant genes across different chickpea genetic backgrounds remains poorly understood. This study evaluated the potential role of 16 genes involved in defense responses in partially resistant (ILC482) and susceptible (Sarı98) chickpea cultivars. The leaf samples were collected from 2-week-old seedlings at 6, 12, 24, 48, and 72 h post-inoculation (hpi) with A. rabiei and analyzed for differential expression of defense genes using qRT-PCR. Twelve out of 16 genes were differentially regulated between chickpea cultivars. The qRT-PCR analysis indicated that the expression of defense genes was significantly higher in the partially resistant cultivar than that in the susceptible cultivar. The time point of the highest upregulation ratio for defense genes was variable between the cultivars. The expression of glutathione S-transferase, serine/threonine-protein kinase, WRKY gene (CaWRKY16), and wall associated-receptor kinase genes reached maximum levels in the resistant cultivar at 6 hpi, while antimicrobial peptide precursor (SNAKIN2), polymorphic antigen membrane protein, ethylene receptor-like sequences (CaETR1), and two nucleotide-binding site-leucine-rich repeat genes showed the highest activity at 24 hpi. In particular, CaWRKY16, CaWRKY50, glutathione S-transferase, CaETR1, and wall-associated-receptor kinase genes provided valuable information for assessing chickpea cultivars with different resistance levels. The results indicated that the expression changes of these genes involved in defense pathways play a crucial role in enhanced resistance of chickpea plants against Ascochyta blight and, therefore could be potential candidate genes for future breeding studies.

Screening of Chickpea genotypes from different agro-climatic areas against Fusarium oxysporum f.sp. ciceris (race 3) using morphological and molecular marker

Fusarium oxysporum f.sp. ciceris (FOC), an extremely destructive pathogen, infects chickpea plants leading to over 100% losses. Although using chemicals like Carbendazim and Mancozeb control the disease but ruin the soil’s natural flora and fauna. Also, the emergence of new FOC races threatens the current genotypes. Many efforts have been made towards improving chickpea genotypes through breeding and selection, but the situation has not been improved over the last 2 decades. The current research uses pot screening and molecular-based approaches to screen out the resistant chickpea cultivars. In that view, the present research uses 16 chickpea genotypes collected from diverse agro-climatic areas and checked against FOC race-3. After the pot screening and ANOVA (P<0.001), the genotypes were categorized as highly Resistant (C 235, HC 1), resistant (GNG 2477, PHULeG 0517, GNG 2171, HC 7, PHULe G 0127), susceptible (ICCV 10) and highly susceptible (PUSA 547, RSG 931, RSG 888, ICCV 512, CSJ 513, ICCV 6). In Marker-assisted selection (MAS), the DNA of genotypes was subjected to PCR with STMS markers TA-96 and TA-27. The results revealed that the genotypes ICCV 512, C 235, GNG 2171, ICCV 10, HC 7, PHULe G 0127 and HC 1 were resistant. These results are significant for selecting resistant genotypes and can be utilized in the future validation and development of more wilt-resistant chickpea genotypes. Our results based on pot-screening and molecular-based datasets suggested a more reliable identification system for screening of FOC resistance cultivar inhibiting, which can help narrow down the selection.

Molecular screening for Fusarium oxysporum resistance genes in chickpeas

Root rot and wilt (Fusarium oxysporum) are the most common pathogens among grain legumes, which cause yield losses of 10 to 40%. Wilt caused by Fusarium oxysporum f.sp. ciceris is a devastating disease in chickpea growing area. In this study, 50 chickpea genotypes were studied to identify genetic sources of resistance to the disease in 2021 and 2022 vegetative seasons. The studies were carried out against the natural background of the experimental field at the Saimasai Agrotechnopark site of the Kazakh National Agrarian Research University, and the studies were carried out against an artificial background at the experimental site of Agropark Ontustik LLP located in the village of Zhalpaksay, Almaty region, Karasai district. The resistance and susceptibility of the plants to F. oxysporum were determined four weeks after artificial inoculation. In field trials, 70% of the genotypes were resistant to wilt and the remaining 30% showed susceptibility to the disease with varying degrees. Molecular methods were used to identify genetic sources of resistance. In the molecular analysis, all 50 genotypes were screened using the primers CaSTMS2, TA200, TA194, TA72, TA46, TR29 and TR7, which are closely related markers to resistance genes. Marker selection can identify resistant genes when screening chickpea genotypes for this pathogen. As a result of screening, resistant chickpea genotypes have been identified that can be used in the breeding program to develop F. oxysporum resistant chickpea varieties.

Distribution of Chickpea (Cicer arietinum L.) Ascochyta blight (Didymella rabiei) and analyses of factors affecting disease epidemics in Central Ethiopia

Ascochyta blight (caused by Didymella rabiei) is one of the most important diseases affecting chickpea production and productivity. The distribution, incidence and severity of the disease, and the association of agronomic practices and environmental factors on the intensity of the disease mainly remained undermined. Chickpea field surveys were conducted in two main chickpea growing regions of central Ethiopia during the 2020 and 2021 main cropping seasons to determine the distribution and importance of Ascochyta blight and analyse its association with biophysical factors. A total of 366 chickpea fields were surveyed in five zones, and 76.6% of the fields were infected with Ascochyta blight. The results revealed that the overall mean prevalence and incidence of the disease ranged from 46.66 to 100%. Ascochyta blight in the infected fields had a mean severity index of 40.17%. The mean disease incidence was higher in fields at altitudes below 2129 m.a.s.l (39.2%) than the mean incidence of fields at higher altitudes. Using logistic regression analysis, the independent variables—zone, altitude, cropping season, seed source, cultivar type, variety, planting pattern, and plant density—were shown to have significant effects on the severity index (P < 0.001). High weed density, growth stage, planting time, crop rotation, Fusarium wilt, pod borer, aphid spp., and dry root rot were also significantly associated (P < 0.05) with Ascochyta blight epidemics. The highest severity (SI = 60.3%) was obtained in Arsi Zone, and the lowest in South West Shewa Zone (SI = 32.1%). The results of this survey indicate that planting chickpea in the middle of the main rainy season, proper weed management, planting improved varieties, and crop rotation should be practiced to reduce the negative impact of the disease until effective resistant chickpea varieties are developed. Furthermore, it is recommended that effective and feasible integrated management options need to be developed against the disease to boost the production and productivity of the crop.

Identification of multi-race Fusarium wilt resistance in chickpea (Cicer arietinum L.) using rapid hydroponic phenotyping

Fusarium wilt, caused by Fusarium oxysporum f. sp. ciceris (Padwick) Matuo and K. Sato is a major cause for low productivity of chickpea. Presence of multiple pathogenic races makes it difficult for the breeder to screen for Fusarium wilt resistance. Twenty-two chickpea genotypes were grown in Hoagland solution and inoculated with five different F. oxysporum races two isolates of each race), including host and pathogens from the major chickpea growing region of India. The resistant chickpea line “WR 315” showed a “highly resistant” reaction, and the susceptible line “JG 62” showed a “highly susceptible” reaction across all pathogen races and isolates. However, the parent lines “Pusa 372” and “JG 11” showed “susceptible” reactions, while the marker-assisted backcrossing (MABC) lines of “Pusa 372” (IL.11,12,14) and “JG 11” (IL.15,16,17) were superior for assessed characters (lengths of roots and shoots, fresh and dry weights), and were highly resistant to most races. This is the first study to use race specific screening of MABC lines using hydroponic host culture in chickpea.

Drought stress resistance indicators of chickpea varieties grown under deficit irrigation conditions.

The aim of this study was to determine the drought stress resistance of three chickpea cultivars (Inci, Hasanbey and Seçkin) grown under water deficit conditions and to discuss the use of yield, crop water stress index and chlorophyll index values as drought stress tolerance indicators in breeding studies. Three drought stress levels, (full irrigation = no stress - I100, deficit irrigation = moderate stress - I50, and no irrigation = severe stress - I0) were used as irrigation treatments. The highest seed yield (1,984 kg ha-1) in severe stress conditions was recorded for the Inci cultivar with a low crop water stress index (CWSI) (0.50) and high chlorophyll index (33.60 SPAD). The lowest seed yield (1,783.66 kg ha-1) in I0treatment was noted for the Seçkin cultivar which had a high CWSI (0.58) and low chlorophyll index (32.88 SPAD). The highest seed yield (2,566.33 kg ha-1) in full irrigation was recorded for the Inci cultivar which had a low CWSI (0.19) and high chlorophyll index (44.39 SPAD), while the lowest seed yield (2,328.00 kg ha-1) in I100 treatment was recorded for the Seçkin cultivar which had a high CWSI (0.26) and low chlorophyll index (42.12 SPAD). The seed yield of the Hasanbey cultivar in both severe stress (1,893 kg ha-1) and full irrigation (2,424.00 kg ha-1) conditions was between Inci and Seçkin varieties. The chlorophyll index and yield had a significant positive (r = 0.877) correlation, while a significant negative (r = -0.90) relationship was determined between CWSI and yield. Seed yield of the Inci cultivar in I0and I100treatments and water use efficiency revealed that the Inci cultivar is resistant to drought stress. Therefore, the Inci cultivar can be used in drought stress tolerance studies. In addition, the CWSI and chlorophyll index values can be employed as resistance indicators in chickpea breeding studies to determine the drought resistant chickpea cultivars.

Ascochyta Blight in Chickpea: An Update.

Chickpea (Cicer arietinum L.), one of the most cultivated legumes worldwide, is crucial for the economy of several countries and a valuable source of nutrients. Yields may be severely affected by Ascochyta blight, a disease caused by the fungus Ascochyta rabiei. Molecular and pathological studies have not yet managed to establish its pathogenesis, since it is highly variable. Similarly, much remains to be elucidated about plant defense mechanisms against the pathogen. Further knowledge of these two aspects is fundamental for the development of tools and strategies to protect the crop. This review summarizes up-to-date information on the disease's pathogenesis, symptomatology, and geographical distribution, as well as on the environmental factors that favor infection, host defense mechanisms, and resistant chickpea genotypes. It also outlines existing practices for integrated blight management.

Unravelling the mechanism of Fusarium wilt resistance in chickpea seedlings using biochemical studies and expression analysis of NBS-LRR and WRKY genes

The yield potential of chickpea is highly compromised because of Fusarium wilt stress. Plant employs a series of physiological, biochemical and molecular changes to restrict pathogen spread. To understand the biochemical basis of resistance in chickpea against Fusarium oxysporum f.sp. ciceri (Foc), the temporal changes in antioxidant enzyme activity profiles were investigated. We documented guaiacol peroxidase, catalase, ascorbate peroxidase, and superoxide dismutase enzyme activities in resistant (WR 315) and susceptible (JG 62) chickpea genotypes under control and wilt stress conditions at two time points, 2- and 10- days post inoculation. Biochemical studies suggest that early and rapid defense responses, against pathogen attack, restrict pathogen spread in resistant cultivar while a weak and slow response by susceptible genotype leads to aggressive colonization by the pathogen. We have identified a set of wilt stress responsive nucleotide binding site and leucine rich repeat (NBS-LRR) resistance (R) and WRKY genes, known to be involved in plant defense, based on their co-localization with previously reported major Foc resistance QTLs and expression profiles. Sixteen NBS-LRR and eleven WRKY genes were co-localized to previously reported ten major Foc-QTLs present in chromosome 2 and 6. Interestingly, majority of these genes were co-localized to chromosome 2 which is also considered as a hotspot for Fusarium wilt resistance. The gene expression analysis in contrasting chickpea genotypes in response to Foc infection identified fourteen NBS-LRR and nine WRKY genes that showed differential expression suggesting their involvement in Fusarium wilt resistance. Our study provides new insights into biochemical and molecular mechanisms underlying resistance and susceptibility in chickpea against Fusarium oxysporum infection.

STMS markers related to Ascochyta blight resistance in chickpea

Chickpea (Cicer arietinum L.) is one of the important legume crops and is cultivated in large-scale throughout Türkiye as well as the world. Ascochyta blight, caused by the fungal phytopathogen Ascochyta rabiei, is the leading reason for the highest yield losses among the diseases known for chickpea. The pathogen exhibits high genetic diversity in Türkiye. Therefore, resistancy using Sequence Tagged Microsatellite Site (STMS) markers related with the genes that provide resistant against Ascochyta blight was investigated for the 205 chickpea breeding lines grown in different parts of Türkiye. The analysis for Ascochyta blight resistance was performed using Ta2, Ta146 and Ts54. It was demonstrated that Ta2, Ts54 and Ta146 were the STMS markers having distinguishable features for the detection of Ascochyta blight resistance and were shown to be used in credible fashion for the selection of resistant chickpea breeding lines.

A Genotype-Independent, Simple, Effective and Efficient in Planta Agrobacterium-Mediated Genetic Transformation Protocol.

Crop improvement under changing climatic conditions is required to feed the growing global population. The development of transgenic crops is an attractive and conceivably the most effective approach for crop improvement with desired traits in varying climatic situations. Here, we describe a simple, efficient and robust in planta Agrobacterium-mediated genetic transformation method that can be used in most crops, including rice, wheat and cotton, and particularly in tissue culture recalcitrant crops, such as chickpea and pigeon pea. The protocol was successfully used for the development of transgenic chickpea and pigeon pea lines for resistance against pod borer. Transgenic lines in chickpea, pigeon pea and wheat were also developed for salt stress tolerance. These lines exhibited improved salt tolerance in terms of various physio-biochemical parameters studied. Since the protocol is rapid, as no tissue culture step is involved, it will significantly contribute to the improvement of most crops and will be of interest for plant biologists working with genetic engineering or genome editing.

Overexpression of CaMYB78 transcription factor enhances resistance response in chickpea against Fusarium oxysporum and negatively regulates anthocyanin biosynthetic pathway.

Chickpea, an important grain legume, suffers from considerable loss of yield due to Fusarium wilt disease. Inaccessibility of resistant gene pool among cultivars and lack of report of resistance, genes from alien sources have been the major constraints for resistance development in this valuable crop. However, along with some other transcription factors, MYB78 was significantly upregulated during chickpea-Fusarium interplay in resistant chickpea genotype. Beinga highly recalcitrant species, thetransformation of this important crop remained non-reproducible until recently. Following a tissue culture independent plumular meristem transformation protocol, introgression of CaMYB78 TF finally became feasible in chickpea. The overexpressed plants developed resistance against the pathogen but the anthocyanin production in transformed flowers was perturbed. In silico analyses of the anthocyanin biosynthetic key gene promoters reported the occurrence of multiple MYB-binding cis elements. Detailed molecular analyses establish the differential regulatory roles of CaMYB78, resistance response against Foc1 on one hand and suppression of pigmentation during flower development on the other, which is an innovative finding of its kind.

Differentiation of an Iranian resistance chickpea line to Ascochyta blight from a susceptible line using a functional SNP

Identification of resistant sources to Ascochyta blight (AB) has been considered as a main purpose in most chickpea breeding programs. Achievements to molecular markers related to resistance to Ascochyta rabiei allows selection programs to be developed more accurately and efficiently. The aim of this study was to investigate the applicability of a functional SNP in differentiating Iranian resistant cultivars to be used in selection programs. Amplification of SNP-containing fragment with specific primer pair and its sequencing resulted in tracking and determining the allelic pattern of SNP18, SNP18-2147, SNP18-2491 and SNP18-2554 loci belong to GSH118 gene in ILC263 (sensitive) and MCC133 (resistant) chickpea lines. Mutations in SNP18 and SNP18-2147 occur at the protein level at positions 499 and 554. Bioinformatics studies have shown that the GSH118 gene is a Lucien-rich repeat receptor kinases (LRR-RKs) and encodes a membrane protein which can be involved in recognizing microorganisms and initiating immune signaling pathways in plants. Additional studies to determine the function of this gene and its interaction with other proteins can be effective in gaining more knowledge about the molecular basis of resistance against AB.

Antagonistic and growth-promoting potential of multifarious bacterial endophytes against Fusarium wilt of chickpea

BackgroundChickpea is the most important legume crop in India, and its productivity is significantly lowered due to biotic constraints such as wilt caused by Fusarium oxysporum f. sp. ciceris. Endophytes help plants to thrive better under stress conditions by regulating plant hormones and inducing systemic resistance. The aim of the present study was to identify chickpea root bacterial endophytes having antagonistic ability for the management of the Fusarium wilt.ResultsTwenty endophytic bacterial strains were isolated from the susceptible and resistant chickpea cultivar, amongst which 35% bacterial endophytes gave positive results for siderophore and 15% isolates were HCN producers, whereas 55% showed good growth on ACC-supplemented medium. Based upon 16S rRNA phylogenetic analysis, efficient endophytic bacterial isolates CRBE1, CRBE3 and CRBE7 were identified as Priestia megaterium, Brucella haematophila and Microbacterium paraoxydans, respectively. Bacterial endophyte CRBE7 and CRBE3 showed pronounced antagonistic activity against Fusarium oxysporum f. sp. ciceris under in vitro conditions. Inoculation of chickpea with isolated bacterial endophytes alone and in combination through seed priming resulted in significant biocontrol activity against Fusarium wilt of chickpea under screenhouse conditions. Biopriming of chickpea seeds alone with CRBE3 and as consortium of CRBE3 + CRBE7 upsurged the phenol content in susceptible and resistant chickpea varieties JG 62 and HC 3, which indicated the role of promising endophytes as potential bio-agents under in vivo conditions.ConclusionsChickpea root bacterial endophytes Priestia megaterium (CRBE1), Brucella haematophila (CRBE3) and Microbacterium paraoxydans (CRBE7) exhibiting antagonistic activity could be incorporated in integrated disease management module against Fusarium wilt of chickpea.

Effects of Host Plant Resistance and Fungicide Applications on Ascochyta Blight Symptomology and Yield of Chickpea.

Ascochyta blight (AB), caused by the pathogen Ascochyta rabiei, is a major threat to chickpea production worldwide, causing major yield losses and decreasing quality. Control of AB requires integrating pest management options including resistant cultivars and fungicide applications. To address this, fungicides with different modes of action were evaluated on three chickpea cultivars with differing levels of susceptibility to AB under irrigated and dryland conditions in 2015 to 2017. The fungicides were applied once or twice and compared with a no-fungicide application control on AB score and yield. The mean grain yields across locations and years were 1,753, 1,283, and 981 kg/ha, with a corresponding AB mean score of 2.6, 3.2, and 3.3 on 0 to 7 scale (where 0 is no disease and 7 is completely dead) for the moderately resistant, moderately susceptible, and susceptible chickpea cultivars, respectively. Fungicide application was not enough to control disease throughout the season. The use of AB-resistant cultivars had the most significant impact on minimizing the disease and maximizing yield, irrespective of year and location. This study supports previous research indicating that planting AB-resistant chickpea cultivars is essential for disease control, regardless of the fungicides applied.