Background: Chickpea (Cicer arietinum L.) production is affected by many biotic factors, among them Fusarium wilt caused by Fusarium oxysporum f. sp. ciceri and Botrytis gray mold caused by Botrytis cinerea led to severe losses. As fungicide application is not advisable, biological management is the best alternative for plant protection. The rhizosphere-dwelling antagonistic bacteria are one of the important successful alternative strategy to manage these diseases of chickpea. Rhizosphere dwelling bacteria serve as biocontrol agents by different mechanisms like producing antibiotics, different enzymes, siderophores against pathogens and thereby reducing the growth of pathogens. Results: The present study aimed to isolate rhizospheric bacteria from the soils of different chickpea fields to evaluate biocontrol efficacy of the isolated bacteria to manage Fusarium wilt and Botrytis gray mold in chickpea. A total of 67 bacteria were isolated from chickpea rhizosphere from Bundelkhand region of India. Study revealed the isolated bacteria could reduce the Fusarium oxysporum f. sp. ciceris and Botrytis cinerea infection in chickpea between 17.29 and 75.29%. After screening of all the bacteria for their biocontrol efficacy, 13 most promising bacterial isolates were considered for further study out of which, three bacterial isolates (15d, 9c and 14a) have shown the maximum in vitro antagonistic effects against Fusarium oxysporum f. sp. ciceri and Botrytis cinerea comparable to in vivo effects. However, Isolate (15d) showed highest 87.5% and 82.69% reduction in disease against Fusarium wilt and Botrytis gray mold respectively, under pot condition. Three most potential isolates were characterized at molecular level using 16S rRNA gene and found to be Priestia megaterium (9c and 14a) and Serratia marcescens (15d). Conclusion: This study identified two native biocontrol agents Priestia megaterium and Serratia marcescens from the rhizospheric soils of Bundelkhand region of India for control of Fusarium wilt, Botrytis gray mold. In future, efforts should be made to further validate the biocontrol agents in conjugation with nanomaterials for enhancing the synergistic effects in managing the fungal diseases in chickpea. This study will definitely enhance our understanding of these bioagents, and to increase their performance by developing effective formulations, application methods, and integrated strategies.

Introduction: Fusarium wilt of chickpea, caused by Fusarium oxysporum f. sp. ciceris (FOC), is a major soil-borne disease that severely affects chickpea production worldwide. The present study aimed to isolate and characterize endophytic bacteria from different plant species and evaluate their antagonistic potential against FOC. Methods: Endophytic bacteria were isolated from leaves, stems, and roots of various plant species. A total of 73 bacterial isolates were obtained from 210 plant samples and screened for antagonistic activity against FOC under in vitro and in vivo conditions. Five promising isolates were selected for detailed studies, including biochemical characterization, stress tolerance assays (salinity, heat, and drought), and molecular identification through 16S rRNA gene sequencing. Results: The selected isolates were identified as Ochrobactrum quorumnocens, Bacillus velezensis, Alcaligenes faecalis, Bacillus subtilis , and Acinetobacter schindleri . These isolates exhibited significant inhibition of FOC on potato dextrose agar (PDA), with inhibition percentages of 36.29%, 48.48%, 45.89%, 57.37%, and 55.50%, respectively. Under field conditions, all five isolates significantly reduced disease incidence and enhanced chickpea growth compared to the untreated control. Discussion: The findings demonstrate that the selected endophytic bacterial isolates possess strong antagonistic activity against FOC and also exhibit plant growth-promoting traits. These isolates have considerable potential as biocontrol agents and PGPR for sustainable management of chickpea Fusarium wilt under both laboratory and field conditions.

This experiment aimed to evaluate the genetic diversity in chickpea germplasm and select superior accessions for breeding resilient, high-yielding varieties in the Bundelkhand region. Two hundred and four germplasm accessions (204) were evaluated in a replicated augmented‐block design with four check varieties across five blocks. Principal component analysis revealed a significant amount of genetic diversity within the germplasm, as 12 principal components (PCs) were identified. The first five PCs, with eigenvalues greater than one, accounted for 74.966% of the variability among the accessions, while PCs 6 to 12 had eigenvalues less than one, indicating minimal contribution to the overall variation. PC1 showed a positive correlation with seed yield, biomass, and the number of pods per plant, highlighting its importance for productivity potential. Accessions with high PC1 scores could be advantageous for high-yield breeding programs. The characteristics that weighed most heavily on PC2 included days to flowering, days to maturity, and seeds per pod, indicating its relevance in determining growth duration and reproductive efficiency. This may help identify early- or late-maturing genotypes that are suitable for specific growing environments. Similarly, PC3 was primarily associated with plant height and 100-seed weight, while PC4 was positively related to the number of secondary branches per plant. The total genotypes were grouped into 10 clusters, with the highest inter-cluster distance found between cluster 1 and cluster 7 (6.7), indicating that these two clusters exhibit the most distinct genetic variations. Genotypes from these groups could be used to generate genetic diversity. These findings emphasize the genetic variability present in chickpea germplasm and its potential for breeding resilient varieties tailored to the agro-climatic conditions of Bundelkhand.

Background: Shallots are infected by various viruses like Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV), Shallot latent virus (SLV) and Shallot virus X (ShVX). In India, they have been found to be persistently infected by ShVX. ShVX also infects onion and garlic in combination with other carlaviruses and potyviruses. ShVX is a member of genus Allexivirus of family Alphaflexiviridae. ShVX has a monopartite genome, which is represented by positive sense single-stranded RNA. Globally, only six complete and 3 nearly complete genome sequences of ShV X are reported to date. This number is insufficient to measure a taxon’s true molecular diversity. Moreover, the complete genome sequence of ShVX from Asia has not been reported as yet. Therefore, this study was undertaken to generate a complete genome sequence of ShVX from India. Results: Shallot virus X (ShVX) is one of the significant threats to Allium crop production. In this study, we report the first complete genome sequence of the ShVX from India through Next-generation sequencing (NGS). The complete genome of the ShVX (Accession No. OK104171), from this study comprised 8911 nucleotides. In-silico analysis of the sequence revealed variability between this isolate and isolates from other countries. The dissimilarities are spread all over the genome specifically some non-coding intergenic regions. Statistical analysis of individual genes for site-specific selection indicates a positive selection in NABP region. The presence of a recombination event was detected in coat protein region. The sequence similarity percentage and phylogenetic analysis indicate ShVX Indian isolate is a distinctly different isolate. Recombination and site-specific selection may have a function in the evolution of this isolate. This is the first detailed study of the ShVX complete genome sequence from Southeast Asia. Conclusion: This study presents the first report of the entire genome sequence of an Indian isolate of ShVX along with an in-depth exploration of its evolutionary traits. The findings highlight the Indian variant as a naturally occurring recombinant, emphasizing the substantial role of recombination in the evolution of this viral species. This insight into the molecular diversity of strains within a specific geographical region holds immense significance for comprehending and forecasting potential epidemics. Consequently, the insights garnered from this research hold practical value for shaping ShVX management strategies and providing a foundation for forthcoming studies delving into its evolutionary trajectory.