Identifikasi Perubahan Fenotip pada Dua Varietas Jagung (Zea mays L.) Akibat Perlakuan Kolkisin

Abstract

Maize is the second most important food source after rice. Genetic improvement in corn plants can be done through mutation breeding activities that will produce phenotypic changes that are useful in increasing genetic diversity in corn plants. This study aims to identify phenotypic changes that appear due to the effect of colchicine treatment on two tested corn varieties. This research was conducted at Jalan Sedayu Raya, Tanjung Gusta, Sunggal District, Deli Serdang Regency, North Sumatra and at the Biology Laboratory of the Faculty of Mathematics and Natural Sciences, University of North Sumatra from September 2022 to April 2023. This study used the method of group randomized design (RAK) with soaking treatment at the same time of 12 hours and with 2 treatment factors. The first factor is variety (V): V1 (Bonanza F1), V2 (Purple Srikandi). The second factor is colchicine concentration (K): K0 (0 ppm), K1 (250 ppm), K2 (500 ppm). The observed variables were chromosome observation (number of chromosomes and karyotype), quantitative characters (plant height, number of leaves, male flowering age, female flowering age, harvest age, number of cobs per plant, cob length, number of seeds per cob, number of rows per cob, 100 seed weight per plot and production weight per plant), qualitative characters (male flower color, female flower color, seed color and seed shape). The results showed that the administration of colchicine at a concentration of 250 ppm produced aneupoliploid chromosomes and at a concentration of 500 ppm produced tetraploid chromosomes. The concentration of colchicine had a significant effect on the parameters of plant height 5-6 weeks after planting, number of leaves 4-6 weeks after planting, female flowering age, harvest age, cob length, number of seeds per cob and weight of 100 seeds per plot. In the qualitative character of seed color, there are differences in the color of seeds produced in each treatment concentration, in the V1K0 treatment produces yellow seeds, in V1K1 produces orange yellow seeds, in V1K2 produces orange seeds and in the V2K0 treatment produces purple seeds, in V2K1 produces purplish red seeds and in V2K2 produces reddish seeds. The interaction between varieties and colchicine concentration had no significant effect on all parameters.