Seventy-four accessions of wild Arachis species along with a susceptible line TMV 2 belonging to A. hypogaea were evaluated for resistance to late leaf spot and rust under greenhouse environment. The experiment was conducted twice to confirm the resistance of the accessions. Percentage of leaf area damaged and disease score on a 1 to 9 scale for late leaf spot and rust were recorded for all accessions in both experiments. Additionally, percentage of defoliation was recorded for late leaf spot. One accession, ICG 8190, of A. hoehnei and one accession, ICG 13199, of A. duranensis were asymptomatic to late leaf spot in both experiments. In addition, 26 accessions were classified as resistant, 10 accessions were moderately resistant, and the remaining 36 accessions exhibited a susceptible reaction to late leaf spot. Only one accession, ICG 8954 of A. kuhlmannii, remained asymptomatic to rust in both experiments. All other accessions, except ICG 8206 of A. ipaensis, ICG 8197, ICG 8198, ICG 11549, and ICG 13178 of A. monticola, and ICG 13171 of A. stenosperma were classified as highly resistant to rust. Four accessions of A. monticola were susceptible to late leaf spot and rust.

Host plant resistance is the major component in the management of fungal diseases in chickpea (Cicer arietinum). We screened a chickpea mini-core collection composed of 211 germ plasm accessions representing the diversity of the global chickpea germ plasm collection of 16,991, maintained at the International Crops Research Institute for the Semi-Arid Tropics to identify sources of multiple disease resistance. The accessions were screened for resistance against As-cochyta blight (Ascochyta rabiei), Botrytis gray mold (Botrytis cinerea), Fusarium wilt (Fusarium oxysporum f. sp. ciceris), and dry root rot (Rhizoctonia bataticola) under a controlled environment. High levels of resistance were observed to Fusarium wilt (FW), where 21 accessions were asymptomatic and 25 resistant. In all, 3, 55, and 6 accessions were moderately resistant to Ascochyta blight (AB), Botrytis gray mold (BGM), and dry root rot (DRR) respectively. ICC 11284 was the only accession moderately resistant to both AB and BGM. Combined resistance also was identified for DRR and FW in 4 accessions, and for BGM and FW in 11 accessions. Through this study, chickpea germ plasm accessions were identified that possess high levels of resistance to more than one fungal disease and would be useful in chickpea multiple disease resistance breeding programs.

Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. ex. Fr., is an economically important disease of chickpea (Cicer arietinum L.), especially in areas where cool, cloudy, and humid weather persists. Several epidemics of BGM causing complete crop loss in the major chickpea-producing countries have been reported. The pathogen B. cinerea mainly survives between seasons on infected crop debris and seeds. Despite extensive investigations on pathological, physiological, and molecular characteristics of B. cinerea causing grey mould type diseases on chickpea and several other hosts, the nature of infection processes and genetic basis of pathogen variability have not been clearly established. This lack of information coupled with the need for repeated application of chemical fungicides forced the deployment of host plant resistance (HPR) as a major option for BGM management. Effective and repeatable controlled-environment and field-screening techniques have been developed for identification of HPR. Of the selected portion of chickpea germplasm evaluated for BGM resistance, only few accessions belonging to both cultivated and wild Cicer spp. were tolerant to BGM, and the search for higher levels of disease resistance continues. Fungicide application based on disease predictive models is helpful in precision-based fungicide application. Integrated disease management (IDM) of BGM has proved more effective than any of the individual disease management components in large-scale, on-farm studies conducted in India, Nepal, and Bangladesh. Further information on the biology of B. cinerea and epidemiology of the disease is needed to strengthen the IDM programs. In this paper the biology of B. cinerea including its variability, epidemiology of BGM, identified sources of resistance, and other management options, and available information on biochemical and genetic basis of disease resistance have been reviewed with a mention of future research priorities.

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