Assessment of Genetic Diversity of Maize (Zea mays L.) Inbreds for Starch Content, Yield and Yield Contributing Traits
K. Harshitha *
Department of Genetics and Plant Breeding, College of Agriculture, Professor Jayashankar Telangana Agricultural University, Rajendranagar, Hyderabad, Telangana, India.
D. Bhadru
Department of Genetics and Plant Breeding, Maize Research Unit, Agricultural Research Institute (ARI), Rajendranagar, Hyderabad, Telangana, India.
K. Lakshmi Prasanna
Department of Seed Science and Technology, Seed Research and Technology Centre (SRTC), Rajendranagar, Hyderabad, Telangana, India.
B. Mallaiah
Department of Plant Pathology, Agricultural Research Institute (ARI), Rajendranagar, Hyderabad, Telangana, India.
*Author to whom correspondence should be addressed.
Abstract
Genetic diversity among parental inbred lines is essential for developing productive maize hybrids with improved grain quality. This study assessed genetic diversity among 30 maize (Zea mays L.) inbred lines for starch content, grain yield and ten yield-contributing traits. The experiment was conducted during Rabi 2025–26 at the Maize Research Unit, Agricultural Research Institute, Rajendranagar, Hyderabad, using a randomised block design with three replications. Starch content was quantified by the anthrone method, and the data were analysed through analysis of variance, Mahalanobis D² statistics, Wilks’ criterion and Tocher’s clustering. Significant differences were detected among the inbred lines for all 12 traits, indicating substantial genetic variability. The genotypes were distributed across 11 clusters, and inter-cluster distances ranged from 19.50 to 179.01. The greatest divergence occurred between Clusters VI and IX. Ear height contributed most to total genetic divergence, followed by ear length and ear girth. Starch content ranged from 50.82% to 63.51%, while yield per plant ranged from 81.53 to 127.57 g. BML 51 and BML 7 combined high starch content with superior grain yield and were therefore identified as promising parental lines for simultaneous improvement of both traits. Crosses involving genetically distant clusters may broaden variability, although their heterotic performance requires confirmation through hybrid evaluation and combining-ability studies.
Keywords: Genetic diversity, Mahalanobis D², Tocher’s clustering, starch content, grain yield, heterosis