COMBINING ABILITY, SUPERIORITY AND LATE WILT DISEASE RESISTANT IN NEW YELLOW MAIZE INBRED LINES VIA DIALLEL MATING DESIGN

ABSTRACT
A half diallel (8 x 8) analysis using eight new yellow maize inbred lines, which derived from geographical regions by the National Maize Breeding Program at Sids, Giza, Sakha and Gemmeiza Agricultural Research Stations were evaluated to estimate combining abilities of the eight new yellow maize inbred lines & their crosses of them, identify the superior crosses exceeded high yielding with resistant of late wilt disease & estimate the relation-ship between grain yield and its attributes. The 28 crosses along with two yellow check hybrids; (SC-168 and Pioneer SC-3444) were evaluated at three locations; Sids, Sakha and Nubaria Agricultural Research Stations. Results showed significant differences among the three locations (Loc) for all the studied traits, except days to 50% silking (DTSE). Furthermore, mean squares of genotypes (G), crosses © and their interaction with locations were significantly differences for all traits except ear height (EHT) and ear position% (EP%) of G x Loc and C x Loc. Variances of general combining ability (GCA) and specific combining ability (SCA) were highly significant for all the studied traits, indicating that the importance of additive as well as non-additive types of gene effects in this study. Inbred lines P1, P2 and P5 were the best general combiner for grain yield (GY) and late wilt resistant disease% (LWRD%) toward high yielding and lodging resistant. Three lines; P4, P6 and P8 were the best general combining ability for DTSE, plant height (PHT) and EHT traits toward earliness, short plant and lower ear placement. Two crosses; P1 x P7 and P3 x P4 had SCA effects positive and significant for GY ard. fed.^-1 and LWRD% traits toward high yielding and lodging resistant, respectively. Also, P1 x P3 and P6 x P8 possessed SCA effects positive (desirable) toward short plant, short ear height and lower ear placement toward lodging resistant. In the same vein, cross P6 x P8 had SCA effects negative (desirable) for DTSE toward earliness. Three crosses; P1 x P5, P1 x P7 and P2 x P7 were positive and significantly superiority% relative to the check SC-168 for GY, where scored (5.88*), (13.44**) and (8.74**) in respectively. While, two crosses; P1 x P7 (4.48) and P2 x P7 (0.15) were superiority% positive and not significant relative to the highest yield check SC-3444. These crosses could be recommended to use in maize breeding programs to produce a promising hybrids with high yielding ability and lodging resistant.