Genetic Variability, Correlation and Path Coefficient Analysis in Hybrid Maize (Zea mays L.)

Abstract

The goal of the current investigation was to determine correlation coefficient, path analysis and genetic variability among twenty four maize hybrids for ten characters in a Randomized Block Design (RBD) with three replications at the research field of Plant Breeding Division, Regional Agricultural Research Station, Barisal, Bangladesh Agricultural Research Institute (BARI), Bangladesh during rabi season of 2014-15. The measured traits were Days to 50% tasseling (DT), days to 50% silking (DS), anthesis silking interval (ASI), plant height (PH), ear height (EH), days to maturity (DM), cob length (CL), cob diameter (CD), thousand seed weight (TSW) and yield(yield t/ha). Here yield was considered as dependent variable and the rest of the parameters were independent variable. The data were submitted to analysis of variance and mean values were compared by DMRT test at both 5% and 1% of probability. Positive and significant genotypic, phenotypic correlation coefficient were recorded for yield with cob diameter (rg=0.75**, rp=0.61**), cob length (rg=0.66**and rp=0.42**), plant height (rg=0.62**and rp=0.55**), ear height (rg=0.66**and rp=0.55**) and thousand seed weight (rg=0.36**and rp=0.44**). High genotypic coefficient of variation (GCV) was obtained from anthesis silking interval (17.26), yield (15.17), ear height (13.80) and thousand seed weight (9.43). The highest phenotypic coefficient of variation (PCV) were observed in anthesis silking interval (26.49) followed by yield (20.51), ear height (16.19) and the lowest in days to maturity (0.70). The difference between GCV and PCV of yield indicated that the characters had some environmental influence. The highest heritability was observed for plant height (73.78) followed by ear height (72.67), thousand seed weight (59.52) and days to maturity (55.97) but the lowest heritability identified for days to silking (18.98). The characters with higher values of GCV and heritability of the aforementioned traits were indicative for selection. The plant height had the highest positive direct effect (1.34) on yield followed by days to silking (0.75), cob diameter CD (0.46) and thousand seed weight (0.41), days to maturity (0.21) and cob length (0.20) indicating the effectiveness of direct selection. Direct negative effect on yield was shown by ear height (-1.03), days to tasseling  (-0.52) and anthesis silking interval (-0.50) was indicating the effectiveness of indirect selection.