Optimization of the regeneration culture system from mature embryos and its influencing factors.

In order to establish an efficient tissue culture and regeneration system for genetic transformation of wheat varieties,mature embryos of 12 wheat cultivars were used as explants to study the induction and differentiation of callus,and the effect of three induction medium and one differentiation media(including three ratios of hormone) on mature embryo in vitro culture.The results showed that the L32 medium were better than MS2 and N64 for callus induction,and all of the average induction rate were more than 85%,of which the N64 medium was the highest.All three hormone ratios could induce the differentiation of callus from wheat mature embryo,but there was great difference of differentiation frequency among different treatments.L3 as the basic differentiating medium containing 0.5 mg·L-1 IAA and 1 mg·L-1 KT,had the highest differentiation rate of 55.68%,and the medium of root formation containing 0.2 mg·L-1 IAA and 0.5 mg·L-1 MET,had the highest rooting rate of 37.02%.Wheat genotypes is an important factor to the formation and differentiation of mature embryo callus.The induction rate of callus,plumule rate,differentiation rate and rooting rate of different genotype were remarkably different.Lumai 14,liangxin 99,jimai 21,shannong20,liangxin66 were screened as the suitable material for genetic transformation among the 12 varieties,and their culture systems had been set up.