Maize (Zea mays L.) single-cross hybrids derived from 12 x 12 half-diallel crosses
among selected inbred lines were evaluated for performance of the hybirds and to
determine phenotypic correlations among traits. Varied estimates of broad-sense
heritability (h2B) between locations were found for all characters, indicating the presence
of genotype x location interaction on the genetic performance of the hybrids. One
hundred-grain weight gave the highest h2B estimates at both locations, Field 2 and Share
farm (66.4 and 93.8%, respectively), as well as in the combined analysis (80.2%).
Narrow-sense heritability (h2N) estimates obtained from the variance components method
were generally in agreement with those from the parent-offspring regression method,
although those obtained from the latter were slightly higher for almost all traits. The h2N
estimates for grain yield recorded were 54.0 and 36.7%, at field 2 and Share farm,
respectively, from variance components method, while 44.7 and 34.2%, respectively,
from parent-offspring regression method. Grain yield of the hybrids was most highly
correlated with grain weight and grain weight/ear. Grain yield correlations with grain
weight gave r values of 0.87, 0.90 and 0.91, respectively at field 2, Share farm and the
locations combined, while its correlation coefficients with grain weight/ear were 0.87,
0.81 and 0.90, respectively. Flowering and maturity characters were negatively correlated
with most other characters, indicating that early flowering and maturing hybrids were
more favourable for grain yield and the other characters measured. Among the yield
components themselves, highest correlations were shown between ear weight and grain
weight/ear, where r-values recorded were 0.99, 0.96 and 0.98, respectively at field 2,
Share farm and the locations combined. Promising hybrids identified in the study could
be further utilized in the hybrid maize development programme.
Sriani Sujiprihati, Ghizan Bin Saleh and Eltahir Siddig Ali , 2003. Heritability, Performance and Correlation Studies on Single Cross Hybrids of Tropical Maize. Asian Journal of Plant Sciences, 2: 51-57.