SELECTION OF YIELD CONTRIBUTING TRAITS IN WHITE MAIZE (Zea mays L.)

Abstract

Three white maize hybrid varieties and twelve inbred lines of yellow maize were evaluated for ten parameters at the experimental field of Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh during November 2018-April 2019. The genotypic and phenotypic variances, genotypic and phenotypic co-efficient of variation, heritability, genetic advance, simple correlations, path analysis and linear regression were studied for grain yield and other ten morpho-physiological traits among the genotypes of maize. The genotypes differed significantly for all traits studied. Genetic coefficient of variation was high for leaf length at 30 days after planting (36.52cm), cob length (22.97cm), cob weight (23.95g), kernel per cob (25.34) and yield per plant (37.74g). The root length at 105 days after planting (DAP) (68.74cm), root length at 120 DAP (68.74cm), leaves per plant at 30 DAP (70.27), leave length at 90 DAP (67cm), leave length at 105 DAP (73.50cm), leave length at 120 DAP (73.50cm), cob diameter (69.18cm) showed moderately high broad sense heritability and very high for rest of the traits. Genetic advance in percentage of mean was low for root length at 105 DAP i.e. RL105 (7.50), RL120 (6.95), LL90 (7.34), LL105 (8.77), LL120 (8.77), cob diameter (4.77), 100-kernel weight (5.21) and high for PH120 (21.09), RL30 (25.18), RL75 (26.93), LPP60 (25.28), LPP75 (30.61), LPP90 (28.28), LPP120 (34.86), LL30 (74.83), LL45 (26.62), LL60 (22.42), cob length (45.95), cob weight (49.02), kernel per cob (51.68), yield per plant (77.34) and the rest traits showed moderate. The final plant height at 120 DAP (PH120) exhibited significant negative association with RL45 (r=-0.49**), RL60 (r=-0.71***), RL75 (r=-0.78***), RL90 (r=-0.54***) and for others showed positive. The leaves per plant at 120 DAP (LPP120) exhibited nonsignificant positive association with LL30 (r=0.02), LL60 (r=0.18), cob diameter (r=0.26) and non-significant negative association with LL45 (r=-0.13) and other traits showed significant positive relation to each other. Path analysis revealed that plant height (0.10214), root length (0.45140), leaves per plant (0.65181), cob diameter (0.86270), cob weight (0.30468) and kernels per cob had positive direct effect (0.37719) on yield/plant, leave length (-0.52073), cob length (-0.82606), 100-kernel weight (-0.29441) had negative direct effect on yield/plant. The regression coefficient for independent variable like PH 120, RL 120, LPP 120, LL 120, cob length, cob diameter, cob weight, kernel per cob and 100 kernel weight & the corresponding scatter plot with the dependent variable yield per plant exhibited positive linear regression. Finally it may be concluded that BARI Hybrid Maize-14 performed better followed by BARI Hybrid Maize-13, BARI Hybrid Maize-12 and inbred line-15.