Sequence Cloning, Transformation And Function Analysis Of C Gene To Non-pungent Pepper

Pepper is an important vegetable and well-known for its nutrition and economy values. Capsaicin as the main pungent substances in pungent pepper has many kinds of activity in pharmacology and physiology, and its content is one of the significant standard of pepper characters. Capsaicinoid Synthetase is the last and most pivotal speed-restrained enzyme in Capsaicin Synthetase pathway. We transferred C gene which encodes Capsaicinoid Synthetase into sweet and pungent pepper mediated by Agrobacterium tumefaciens and investigated its function through phenotype variation of the transgenic plants. We expected that our work will be helpful in increasing the capsaicin and the taste flavor improvement of the pepper. Main conclusions are listed as follows:1. The infection of several factors including seedling age, genotypes and explant types are discussed and an efficient regeneration system of pepper cotyledon was established.(1) Buds Regenetation: There are highest regeneration rates of pepper cotyledons of Zhongjiao No.5 and Xiangjiao No.8 of 16d; The explants browning can be avoided effectively with 10mg/L AgNO₃ in regeneration medium; IAA is better than NAA in buds regeneration. A most suitable regeneration medium is MS+6-BA 5.0mg/L+IAA 1.0mg/L+AgNO₃ 10.0mg/L+Sucrose 20g/L+Carrageenan 8.0g/L.(2) Buds Elongation: It is difficult to elongate for the regeneration buds of pepper. The optimal medium for buds elongation was MS with 6-BA 2.0mg/L and IAA 0.3mg/L, additional GA3 2.0mg/L would be better. The rigidity of the medium and the air humidity of the triangle bottle will influence the elongation of the buds seriously. If we add 6.0g/L Carrageenan into medium and seal the bottle with plastic film there will be a basal environment for buds elongation and the effect is evident. The most conformable elongation medium is MS+6-BA 2.0mg/L +IAA 0.3mg/L+GA₃ 2.0mg/L +Sucrose 20g/L +Carrageenan 6.0mg/L.(3) Buds rootage: 1/2MS Medium is better than MS in root formation for the pepper adventitious buds. Low concentration IAA is better than high. The best root formation medium is 1/2MS +NAA 0.1 mg/L +IAA 0.2mg/L+Sucrose 20g/L +Carrageenan 8.0mg/L. It will take about 50-60d from pepper explants to regeneration plantlets.