1Department of Agroecotechnology, Faculty of Agriculture, University of Mataram, Mataram83125, Indonesia
*Corresponding Author: I. W ayan Sudika, Department of Agroecotechnology, Faculty of Agriculture, University of Mataram, Mataram83125, Indonesia. Email: iwsudika@unram.ac.id
Evaluation of genetic parameters under contrasting environmental conditions is essential to determine appropriate selection criteria for advancing lines to the fifth generation (S5) through selfing. This study aims to evaluate the genetic parameters, including genetic diversity, heritability and genotypic correlation of quantitative traits of maize lines under two environmental conditions on dry land.
The experiment was conducted using a randomized complete block design (RCBD) arranged in a split-plot design (SPD). Environmental condition served as the main plot, while genotype was assigned as the subplot, with two replications for each treatment combination. Observations were recorded on growth traits, harvest age, yield and yield components. Data were analyzed using split-plot analysis of variance for combined environmental conditions and randomized block analysis for each individual environment at a 5% significance level. Genetic parameters, including the coefficient of genetic variation, broad-sense heritability and genotypic correlation coefficient (particularly between leaf angle and yield traits), were subsequently calculated.
The genetic diversity for most quantitative traits was relatively narrow under both environmental conditions. However, cob weight and grain yield under drought-stressed conditions showed moderate genetic variability. Heritability estimates were generally low for most quantitative traits observed accross both environments. No significant genotypic correlation was observed between leaf angle with other traits. In contrast, most traits exhibited positive genotypic correlations with yield, ranging from weak (0.361) to strong (0.995) accross both environmental conditions. Advancement to the generation through selfing should involve selection foor taller plants to improve yield under both drought-stressed and normal environmental conditions.
Drought stress, Dryland agriculture, Food security, Genetic variability, Heritability, Maize (Zea mays L.)
