GENETIC EVALUATION OF HYBRIDS IN RELATION TO THEIR PARENTS IN INTRASPECIFIC CROSSES IN MAIZE (Zea mays L.)

Abstract

Information about combining ability is important for making breeding strategies. A 5x5 half diallel cross between inbred lines of maize (Zea mays L.) with an evaluation to estimate the genetic parameters were carried out at Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, to study on Genetic Evaluation of Hybrids in Relation to Their parents in Intraspecific Crosses in Maize. The main objective of this study was to evaluate the yield contributing traits of F, hybrids to 1 check variety and 5 inbred lines, based on a diallel cross (without reciprocals) General Combining Ability (GCA) and Specific Combining Ability (SCA). The components of the genetic variance were calculated using Griffing’s formula (1956), method 2, mathematic model I. The highest value for yield per plant (240.22g) was obtain from combination of the inbred lines P5xP6 where as heterobeltosis was 110.51 and standard heterosis was 12.649, while the minimal average value obtained for the hybrid combination was P1xP5 (142.11g). The variation between the largest and the smallest yield per plant for the hybrid combination was 98.11 g or 59%, but not significant at ANOVA test for the combining ability of GCA and SCA effect. Again for the character of 100-grain yield was found highest in the combination of P5xP6 (57.17g) including with heterobeltosis was 30.79 and standard heterosis was 23.46 where as lowest value was found in P1xP4 (30.7g). For this character, significantly positive heterosis was desirable and hybrids were P1xP2 (F 1), P1xP4 (F 3), P1xP5 (F 4), P2xP3 (F 6), P2xP4 (F 7), P2xP5 (F 8), P3xP5 (F 11), P3xP6 (F 12), P4xP5 (F 13) and P5xP6 (F 15) showed significantly positive heterosis over better parent where as only P5xP6 (F 15) showed positive heterosis over check variety. ANOVA’s test for the combining ability of GCA and SCA effects were highly significant at the p < 0.05 and p< 0.01 level of probability, respectively.