In an attempt to study the association of different agronomic traits in improving qualitative and quantitative aspects of maize correlation studies and path analysis were done. Association studies indicated that characters like plant height, ear height, ear length, ear girth, number of grains per row, number of grains per ear, starch content, hundred grain weight and carotene content showed significant positive association with grain yield. While days to tasseling and days to silking showed positive non-significant association with grain yield. Number of rows per ear and crude protein content recorded negative non-significant association with grain yield. Ear length recorded highest correlation (r = 0.871) with grain yield followed by number of grains per row (r = 0.868). Out of the fourteen traits taken for path analysis, ear length had a maximum positive direct effect on grain yield followed by ear height, number of rows per ear, days to silking, crude protein and carotene content and they contributed primarily to yield and could be relied upon for selection of genotypes to improve genetic yield potential of corn. Plant height, days to tasseling, ear girth, number of grains per row, number of grains per ear, hundred grain weight and starch content recorded negative direct effect on grain yield even though genotypic correlation coefficients on grain yield were positive. The study revealed that direct selection for ear length, ear height and number of rows per ear might be rewarding for yield improvement since they revealed true relationship with grain yield.
Chinnadurai Immanuel Selvaraj and Pothiraj Nagarajan, 2011. Interrelationship and Path-coefficient Studies for Qualitative Traits, Grain Yield and other Yield Attributes among Maize (Zea mays L.). International Journal of Plant Breeding and Genetics, 5: 209-223.