Functional diversity of Finger millet [Eleusine coracana L. Gaertn.] cultural composite for the management of blast [Pyricularia grisea (Cooke) Sacc.] disease

Abstract

Combinations of cultivar mixtures with varying levels of disease resistance show promise in managing plant diseases under reduced fungicide application. Theoretically, canopy architecture influences the expansion of disease epidemics under field conditions. The objective of this study was to evaluate the effect of different combinations of cultivar composites on finger millet blast epidemics and yield sustainability. A composite of advanced pre-released cultures, TNEc 1285, TNEc 1294, and TNEc 1310, combined with the resistant check GE 4449, a leading variety, in a 1:1 ratio, was evaluated against tricyclazole 75% WP under field conditions for leaf blast reactions. Fungicide treatment with tricyclazole 75% WP recorded a lower incidence of leaf blast, with all the treatments tried performing at par with all the treatments across both years. Quantitative measurements of disease epidemics using the area under the disease progress curve indicated a consistent pattern of disease progression across all treatments. The benefit-cost (B:C) ratio, analysed through partial budgeting, identified the cultivar composite as the most effective among all treatments. This approach effectively reduced disease epidemics under field conditions and sustained yield over both years, even with minimal or no chemical/fungicidal inputs.