Aksi Gen dan Daya Gabung pada Persilangan Jagung Ketan Ungu terhadap Karakter Hasil

New superior hybrid development programs continue to be carried out, considering the high demand for corn. Understanding the nature of the action of the genes involved in certain traits is very important to increase crop yields. Diallel crosses are used to determine the actions of additive and non-additive genes controlling of desirable traits. This study aimed to obtain information on gene action and combining ability in purple maize crosses. The research was conducted in Junrejo Sub-district, Batu City, East Java Province, with an altitude of ± 600 m with a daily temperature of 18.1-31.0 ⁰C. The materials used were four parental line of purple corn 12 M-01, 12 M-02, 12 M-03, 12 M – 04. This research was carried out using a full diallel mating design with 16 cross combinations of 4 parents, 6 crosses between parents and 6 reciprocal crosses with three replications. The results showed that the variance in general combining ability (GCA) from highest to lowest was sequentially found in the characteristics of cob diameter (2.7678), weight of corn without cornhusks (1.1522), cob weight (0.8112), weight of 100 seeds (0.426), Brix content (0.3266 ), number of rows of seeds/cobs (0.2238), length of cobs (0.0861) and weight of corn with cornhusks (-1.5091). The variance of specific combining ability (SCA) from highest to lowest in sequence was found in the characteristics of corn weight with cornhusks (49.6993), corn weight without cornhusks (36.1253), cob weight (7.0353), Brix content (3.0065), cob length (2.1695), cob diameter (0.7424), number of rows of seeds/cobs (-0.3573) and weight of 100 seeds (-5.3678). The highest to lowest DGU:DGK variance ratio was found in the characteristics of cob diameter (3.7285), cob weight (0.1153), Brix content (0.1086), cob length (0.0397), weight of corn without cornhusks (0.0319), weight of corn with cornhusks (-0.0304), number of rows of seeds/cobs (-0.06264) and weight of 100 seeds (-0.0794). A ratio value of σ²DGU/σ²DGU that is less than one indicates that the influence of SCA is greater than the influence of GCA. Non-additive gene action is found in the characteristics of number of rows of seeds per cob, cob length, cob weight, weight of 100 seeds, weight of corn without cornhusks, weight of corn with cornhusks and Brix content. The degree of dominance shows that partial dominance occurs in the cob diameter character. Positive over-dominance occurred in several characters of corn weight with cornhusks, corn weight without cornhusks, cob length, cob weight, weight of 100 kernels and Brix content and negative in the character of number of rows of seeds/cobs.