JOINT REGRESSION ANALYSIS OF MAIZE FOR YIELD AND YIELD CONTRIBUTING CHARACTERS

Abstract

The field experiment was conducted during the period from October 2009 to March 2010 in the experimental field of the Department of Genetics and Plant Breeding, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, to study the joint regression analysis of maize for yield and yield contributing characters. The experiment considered as two factors such as: Factor A- Irrigation level such as, I,: 01 irrigation at knee stage, I,: 02 irrigations at knee and preflowering stage and I;: 03 irrigations at knee, pre-flowering and milking stage; Factor B- 10 maize genotypes such as G, (Kanak), G) (Diamond), G3; (HP-100), G4 (Lakkhi), G; (BARI-1), Gs (Durga), G7 (NT-6323), Gg (Seed tee-740), Go (NK-40) and Gyo (Kongvoi). The experiment was laid out in two factors Randomized Complete Block Design (RCBD) with three replications. Mean performance, variability, correlation matrix and joint regression analysis were done on 12 yield contributing and yield characters. Grain yield per plant in terms of phenotypic variation (395.55) was higher than the genotypic variance (219.07) which was supported by narrow difference between phenotypic (9.10%) and genotypic (6.77%) co-efficient of variation. High heritability (55.38%) for grain yield per plant attached with high genetic advance (29.08%) and low genetic advance in percentage of mean (13.31). Plant height (0.319), days to flowering of male (0.290), days to flowering of female (0.399), cob length (0.453), cob diameter (0.501), number of grains per cob (0.246), weight of 1000 seeds (0.376) and ear length (0.429) showed positive significant association with grain yield per plant in maize genotypes. Three irrigations was better for higher grain yield and plant growth of maize. Crop produce with three irrigations gave the proper plant height, tassel height, cob to tassel height, days to flowering of male, days to flowering of female, days to maturity, cob length, cob diameter, number of grains per cob, weight of 1000 seeds, ear length and grain yield per plant. The genotype G, (Lakkhi) produced the highest grain yield (233g/plant) followed by the genotype Gg (Durga) and both the hybrids had nonsignificant regression coefficient and negative deviation from regression, hence response to irrigation was predictable but stability was not ascertained for these two high yielding hybrids over the three levels of irrigation.