Genetic Variability for Mesocotyl Length in Maize

Plant ability to tap moisture from deep-soil zones is crucial to adaptation to water stress environments. The function of the mesocotyl in seedling emergence is established in grasses such as maize. Information is scarce on the extent of genetic variability for mesocotyl length in available maize germplasm. Sixty-eight maize genotypes were studied using Completely Randomized Design in a laboratory experiment to investigate the extent of genetic variability for mesocotyl length (ML), and the relationship among seed biochemical components and ML. Ten seeds of each genotype were germinated for ten days in the dark, using locally-available materials. Mesocotyl length was determined by placing cut mesocotyl from germinated seedlings against a flexible measuring tape. Maize samples were also analyzed for biochemical composition. Analysis of variance revealed highly-significant (p ≤ 0.01) genotype mean squares. Broad-sense heritability and genetic advance were high. Mean mesocotyl length for genotypes ranged from 0.58 to 9.02. Dendrogram from cluster analysis based on Ward’s minimum variance classified 67 of the genotypes into clusters I, II, and III with mesocotyl length (mean ± standard deviation) of 0.49 ± 0.18, 4.25 ± 0.96, and 9.16 ± 0.93 cm respectively. The results of the biochemical analysis and the implications of the results of this study on maize improvement will be discussed at the meeting.