Response of tropical maize inbred lines to high plant density stress in terms of grain yield and disease attributes

Abstract

The significantly lower maize productivity in tropical countries in comparison on temperate zones has always been an area of high concern. The increase in the number of plants per unit area, through the adoption of high plant density (HPD), has been extensively used in temperate maize but this strategy has not been well exploited in tropical maize. The proposed study is to identify HPD adept donor inbreds to generate commercial hybrids to achieve high productivity in tropical/ subtropical maize. A set of 20 inbred lines, selected from diverse origin of tropical maize germplasm pool, was screened under normal plant density (NPD) and high plant density to assess their tolerance to crowding stress in terms of grain yield and prevalent diseases during Kharif season. The present study indicated that maize inbred lines PML 387, PML 503 and PML 892 with good seed yield potential and disease resistance may serve as potential donors to generate crowding stress tolerant hybrids for commercial hybrid breeding programme. With systematic evaluation of HPD amenable parents and hence, generated hybrids, there is a feasibility to enhance the maize productivity on commercial scale with new agronomic intervention of altered plant to plant spacing.