Correlation and path coefficient studies in tropical maize (Zea mays L.) inbreds

A study was carried out to investigate the relationship between grain yield and other important yield contributing characters in maize inbreds through correlation and path coefficient analysis. One hundred and forty-four inbreds were tested in a square lattice design with two replications and the observations were recorded on 12 important characters viz., days to 50% tasseling, days to 50% silking, plant height (cm), number of leaves, ear length (cm), ear girth (cm), number of kernel rows per ear, number of kernels per row, days to maturity, 100-seed weight (g), shelling percentage and grain yield (g/plant). Analysis of simple correlation coefficient showed that all the characters studied had positive correlation with yield. However, significant and high positive correlation with grain yield was recorded by number of kernels per row, ear length, number of leaves, ear girth, plant height, 100-seed weight and days to maturity. Path analysis revealed that number of kernels per row and 100-seed weight had very high direct effect on grain yield. Number of kernel rows showed high direct effect and number of leaves had moderate direct effect on grain yield. Among these, number of kernels per row, 100-seed weight and number of leaves had significant and positive genotypic correlation with grain yield along with high positive direct effect on grain yield, whereas the other characters showed non-significant genotypic correlation with grain yield or negative direct effect on grain yield. Hence, more importance can be given to number of kernels per row, 100-seed weight and number of leaves to develop productive inbreds in maize breeding programmes.