Establishment Of The Transgenic Acceptor System And A Preliminary Study On Genetic Transformation By Agrobacterium-mediated In Rice

Rice (Oryza sativa L.) is one of the most important food crops in the world, and it is also staple food of more than fifty percent population in China. With the living standard being improved, more and more people concern with the nutritional value of rice, especially the content of microelement, protein and required amino acid. Lyine and methionine are required amino acids for people and animal. But they can not be synthesized by themselves, people should absorb it directly from food. Absence of amino acids will bring about a disturbance of body metabolism even some disease relating to physiological function. As staple food of majority, the content of them are very low. And the content of iron in rice is low. The human lactoferrin (hLF) is an iron-binding glycoprotein with widely biological muti-functions, including broad spectrum anti microbial activity and anti-inflammatory and immunoregulatory activities. It can increase the effectivity of iron. In order to adapt to the requirement of people, it is necessary to raise the content of nutrient traits during rice production. We can improve multiple traits of rice by conventional breeding approaches, but it cause long cycle and low efficient. Practice indicated that, introducing multiple genes which present in the same T-DNA region of one plasmid into target rice is an efficient approach to improve multiple traits of rice simultaneously.It is necessary to establish stable, high frequency and easy- differentiated acceptor system in rice transgenic technology in order to realize ideal transformation. In this paper, four rice varieties were selected as material; some principal factors affecting the efficiency on mature embryo and immature embryo culture of rice were studied systematically. And the constitution of medium that inducing embryonic callus from mature embryo were improved in order to establish a stable and high-efficient transformation system. The human lactoferrin (hLF) gene, lysine-rich protein (SB401) gene and a methionine-rich protein (RZ10) gene which were integrated into the same T-DNA region of plasmid P1304, were transferred into rice varieties by using the methods of Agrobacterium-mediated genetic transformation. The research results are as follows:1. The effects on mature embryo sterilization were quite different with sterilant combinations. 75%CH₃CH₂OH 3min + 10%NaClO10min+ 0.1%HgCl₂15min had optimal...