ASSESSMENT OF GENETIC PARAMETERS IN MAIZE (Zea mays L.) FOR YIELD AND ASSOCIATED TRAITS

Abstract

The present study was undertaken during the rabi season of 2024–25 at the Regional
Agricultural Research Station (RARS), Lam, Guntur, Andhra Pradesh, to evaluate the extent of
genetic variability, heritability and genetic advance in maize (Zea mays L.) inbred lines. A total of
50 inbred lines comprising 48 test entries along with two standard checks (LM 13 and LM 14) are
assessed using alpha lattice design with two replications. Data was recorded on thirteen quantitative
traits encompassing phenological, morphological and yield-related parameters. Analysis of
variance revealed highly significant differences among the genotypes for all the traits studied
indicating the presence of considerable genetic variability. The phenotypic coefficient of variation
(PCV) exceeded the genotypic coefficient of variation (GCV) for all traits, reflecting the influence
of environmental factors on trait expression. High estimates of GCV and PCV were observed for
ear height, 100-kernel weight and grain yield per plant suggesting the existence of substantial
variability within the genetic material. Moderate variability was recorded for plant height, ear
length and SPAD chlorophyll meter reading, whereas relatively low variability was observed for
days to 50% anthesis, days to 50% silking and days to maturity. High heritability coupled with
high genetic advance as per cent of mean was recorded for plant height, ear height, number of
kernels per row, 100-kernel weight and grain yield per plant indicating the predominance of additive
gene effects and the potential effectiveness of direct selection for these traits. Moderate heritability
with moderate genetic advance was observed for ear length, ear girth, number of kernel rows per
ear and SPAD chlorophyll meter reading, suggesting the involvement of both additive and nonadditive
gene actions.