使用双抗真菌蛋白基因提高水稻抗病性的研究

Enhancement of Rice Disease Resistance by Two Antifungal Protein Genes

将含有串联的RC24基因和β-1，3－Glu基因的pGB12质粒与含有hpt基因的p35H质粒用基因枪法同时导入华南地区一优良籼稻（OryzasativaL．ssp．indica）品种“七丝软占”中。Southernblot分析证明获得17个同时整合有RC24基因和β-1，3－Glu基因的转基因系。而Northernblot分析表明在不同的转基因系中两基因的表达量存在很大差异。对R1及R2代转基因植株的分子分析表明，这两个基因已稳定遗传到R1、R2代，并在RNA水平上持续表达。转基因植株苗期抗稻瘟病试验表明，部分R1代转基因植株苗对广东省稻瘟病菌（Magnaphorthagrisea）中的5个代表菌株表现出不同程度的抗性提高。而其中18株抗性提高的R1代转基因植株的R2代各苗对广东省稻瘟病菌优势生理小种中的3个代表菌株表现出一致的抗性提高，结合分子分析，初步证明获得10株整合有RC24和β-1，3－Glu双基因的稻瘟病抗性提高的R1代转基因纯系植株。且这些转基因纯系植株的离体叶片对纹枯病菌（RhizoctoniaSolaniKuhn的抗性也明显提高。

Plasmid pGB12 containing a rice basic chitinase gene RC24 and an alfalfa β-1, 3-glucanase gene β-1, 3- Glu and p35H containing hypromycin phosphotransferase gene hpt were simultaneously bombarded into an elite indica rice (Oryza sativa L. ssp. indica ) variety──' Qisiruanzhan' grown in South China. 17 independent lines co-harboring RC24 and β-1, 3-Clu were obtained by Southern blot. Northern blot analysis revealed substantial variations among these transformants. The introduced RC24 and β-1, 3-Clu were stably inherited and expressed in the second and third generations. To the five isolates of Magnaphortha grisea varieties, evaluation of leaf blast of the second generation showed a different degree of resistance- And every progeny of 18 R1 transgenic rice plants showed resistance to the three dominant isolates. Based on bioassay of leaf blast with R2 transgenic rice plants and data from the molecular analyses, ten homlogous transgenic lines were primarily obtained, which exerted higher inhibitor efficiency on the growth of Rhizoctonia solani Kuhn.