Pengaruh Iradiasi Sinar Gamma terhadap Regenerasi Kalus Jeruk Siam Hasil Kultur Protoplas

Abstract

Tangerine cv. Siam has a quite sweet flavour, easily peeld skin, fragant, soft and juicy flesh. But still has relatively many seeds (15-20 seeds per fruit) and the skin color that has not been so attractive, so it can not compete with citrus from other countries. Quality improvement of citrus fruit with little or no seeds is very important. The first step for improvement is to increase the genetic variability of citrus, so that the selection process becomes more efficient. Callus culture from protoplast has a high level of genetic variability. This study aimed to enhance the genetic variability of Tangerine cv. Siam by Gamma ray irradiation treatment on callus from potoplast culture. Calli irradiated at doses of 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 Gray. Observation on the growth of callus showed variation in morphology and weight of callus. At lower doses (10-50 Gray) callus growth were not inhibited, but at higher doses (60-100 Gray) callus growth were very slow. Gamma ray irradiation also affects the formation of somatic embryos than other dose. After 4 weeks on media MW + 0.5 mg/l ABA, 50 Gray callus produced more somatic embryos than the other doses. Germination of somatic embryos from 50 Gray dose, produced more shoots than the other dose after 4 weeks on media MW + 0.5 mg/l GA3