Establishment Of Regeneration System And Study On Genetic Transformation Of Portulaca Oleracea L.

In order to solve the problem of vegetable safety, it was a new way to search eatable types in wild plants and improve them genetically. Portulaceae plants evoked many scholar's great notice on their potential values because of their extensive ecological adaptability and special medical function and high nutrition value. The improvement genetically by modern biotechnology would help to mine their potential values. This paper used Portulaca oleracea L. as material and studied the plantlet regeneration system and the Agrobacterium-mediated transformation system as well as the changes of physiological- biochemical indexes during the growth period of it's callus. The main results were as follows:1. Studied the tissue culture and plantlet regeneration. Using tender leaves and shoots as explants and studying the effects of different hormone combinations on callus induction and plant differentiation, we established the regeneration system of Portulaca oleracea L. as follows: the callus inducing medium was MS+6-BA0.5mg/L +2,4-D0.5mg/L or MS+6-BA0.5mg/L+2,4-D1.0mg/L and the frequency was 100%; the shoot inducing medium was MS+6-BA 4.0mg/L+NAA0.2mg/L and the frequency was 87.5%; the root inducing medium was 1/2MS+IBA2.0mg/L and the frequency was 100%.2. Studied the growth period and physiological- biochemical indexes of the callus. The results showed that the growth period was about 21 days and the growth curve was similar to "S" shape. The growth period could be divided into three phases as follows: lag phase (0~6d), exponential growth phase (6-15d) and stationary phase (15~21d). During the growth period, the content of soluble protein changed with the growth curve accordingly, while the activities of SOD, CAT and POD changed characteristically.