The effects of medium modification on in vitro seed germination and callus induction in tomato

Abstract

Tomato is one of the most important vegetable and it is part of human daily food. High world population growth rate demands to increase the tomato productivity. Tomato is chosen among the researchers due to its high anti-oxidant and mineral properties. In the present study, in vitro response of tomato c.v. Rio Grande was investigated. It was found that when sucrose was used as the source of carbon, the highest germination frequency of 85% was achieved in modified N6 whereas the highest germination rate in modified 2N6 medium was 15.6. In medium supplemented with 1.5 mg/l GA3, 1.5 mg/l BAP and 0.25 mg/l, 0.5 mg/l and 0.75 mg/l of 2, 4-D, the highest callus induction frequency of 39% was observed. In the same time, the highest induction rate of 1.3 was observed in medium supplemented with 1.5 mg/l GA3, 1.5 mg/l BAP and 0.25 and 0.5 mg/l 2, 4-D. Analysis of variance showed significant effects of medium concentration on in vitro seed germination and plant growth regulators on callus induction in different tomato explants. Cotyledons showed better response compared to hypocotyls. These results suggested that sucrose would be a better carbon source either for in vitro germination or callogenesis and cotyledon would be better explants for tissue culture studies.