Maize Stress Breeding and Genetics

Thirty inbreeding lines of Zea mays were screened in a glasshouse. Eight best performing lines were selected based on nine traits screened to cross with testers. The resulting F1 hybrids were screened in the field for their performance. Root and shoot length ratio, fresh shoot weight, dry root weight, and dry shoot weight were the most important traits to be used as criteria in selecting drought tolerance maize genotypes. Principal component analysis suggested that K55TMS, OH3A54, W187R, A556, WA3748, WM13RA and A545 performed the best under normal and drought conditions. High heritability and genetic advance was found for plant height, 100-grain weight, grain rows per plant and grain yield per plant, suggesting that selection of high yielding maize genotypes is possible through this approach. High specific combining ability of W64SP, A495, A509 and A50-2 suggested pre-screening of inbred lines that the inbred lines may be an efficient approach to develop higher yielding maize hybrids through heterosis breeding under drought.