Correlation between downy mildew resistance and yield related traits in cauliflower (Brassica oleracea L. var. botrytis) under sub temperate conditions of North Western Himalayas

A set of twenty-nine genotypes of cauliflower were evaluated to assess the effect of downy mildew disease incidence on yield and yield-related traits. We undertook a comparative analysis of yield and plant disease index under disease stress condition to obtain a first indication of the crucial traits associated with disease resistance in cauliflower. Information about the direct contribution of different traits to downy mildew resistance would be highly important for formulating a selection programme. Plant disease (downy mildew) index showed highly significant negative (desirable) association with marketable yield per plant, net curd weight, gross curd weight, harvest index, curd diameter, curd size index, per cent marketable curds, curd depth and curd compactness at both genotypic and phenotypic levels. So, for the genetic improvement of disease resistance in cauliflower, selection based on the above characters is desirable. Direct and indirect effects showed that marketable yield per plant and curd depth played a crucial role in determining the resistance to downy mildew.