Green Global
Foundation   Journal
...an emerging window for scientific research and publication across the globe

GENE ACTION AND COMBINING ABILITY ASSESSMENT OF FIELD CORN (Zea mays L.) USING LINE × TESTER MATING DESIGN (Pages : 11 - 16)

An elite parental line with good combining ability is mandatory for hybrid-oriented breeding program. In this study, line × tester mating design was used to determine combining ability, type of gene action, genetic variance of yield and yield contributing characters for selecting superior parents of field corn (maize). Ten S5 lines of commercial hybrid NT 6323 were crossed with 2 testers in a line × tester mating design and the resulting 20 crosses along with the parents and standard checks BHM 9, NK 40 and 900 M GOLD were evaluated in a Randomized Complete Block Design (RCBD) replicated twice, during rabi season, 2015-16 at the experimental field of Bangladesh Agricultural Research Institute (BARI), Gazipur, Bangladesh. There were significant differences among the lines for days to 50% silking, plant height, ear height and number of grains per row whereas both testers were insignificant for all the traits though they were from different heterotic group of maize. No significant difference was observed for line × tester interaction except thousand grain weight and yield. Mean squares due to genotype, parents, parents versus crosses and crosses were significant for the most studied traits. Estimation of variance due to GCA, SCA and their ratio revealed intensive non-additive gene effects for all the traits except ear height. Lines NT 6323/S5-21-1-2 and NT 6323/S5-49-1 exhibited significant negative GCA effect for both plant height and ear height. Only NT 6323/S5-50-1line displayed significant negative GCA effect for both of the traits days to 50% tasseling and days to 50% silking. Therefore, lines NT 6323/S5-21-1-2 and NT 6323/S5-49-1 could be used to develop dwarf variety and line NT 6323/S5-50-1for short duration variety. NT 6323/S5-27-1, NT 6323/S5-44-1 and NT 6323/S5-50-1 were good general combiners for grain yield and some of the important yield contributing characters. Cross combinations NT 6323/S5-50-1 x BIL 79 and NT 6323/S5-27-1 × BIL 28 showed significant poDownload