Inheritance studies of Pyrenophora leaf spot resistance genes in oat (Avena sativa L.) crop

Abstract

Oat is a hexaploid cultivated crop known for its usage as a fodder crop mainly, though being a dual purpose crop. Oats are affected by several abiotic and biotic stresses. Among them, foliar diseases like rust, leaf spot, smut, etc, are important and have threatened oat production. Pyrenophora leaf spot, which is a fungal disease that accounts for 40 to 50% yield losses in India. Keeping this in view, a study was conducted to identify the inheritance pattern of Pyrenophora leaf spot resistance genes by the previously developed F2 population involving resistant and susceptible parents. The population showed a minimum of 22% DSI and a maximum of 83% DSI. The result showed that populations derived from parents were separated into 114 resistant individuals and 26 susceptible individuals, fitting into a gene ratio of (13 resistant: 3 susceptible) which is less than a table value with non-significant deviation observed for the trait studied, indicating observed and expected distributions were not same. Further ratio indicated that inhibitory gene action was involved in governing it.