Abstract: The transgenic rice Zhongda 2, genetically modified from a indica rice cultivar Zhuxian B by rice chitinase gene (RC24), had high resistance to rice sheath blight (Rhizoctonia solani) in laboratory and a two-year field experiment. The pathogen could infect the sheath of Zhongda 2 and induce symptom of the disease. There was no difference in time of penetration or incubation period between Zhongda 2 and non-transgenic rice control, Zhuxian B, but the melting hypha was observed early compared with the control. Resistance of Zhongda 2 showed to inhibit the growth of mycelium in host tissue. The preliminary study on resistance of hybrid rice combinations (F₁) of Zhongda 2(♂) crossed withother five non-transgenic rice materials showed that the resistance of F₁ generations were higher than those of non-transgenic maternal parents, but they also changed along with the different maternal parents.

Key words: transgenic rice, chitinase gene, rice sheath blight, resistance

摘要： 导入外源几丁质酶基因“RC24”的水稻中大2号接种纹枯病菌的结果表明，接种病菌后病斑扩展速率和田间病情指数小，表现为对水稻纹枯病高抗。组织病理学研究表明纹枯病菌能侵入中大2号，并引发纹枯病，入侵时间和症状出现的时间与非转基因感病对照没有显著差异，但病菌菌丝体消解现象出现早于对照，其抗病性主要表现为限制病菌扩展。以中大2号与非转基因水稻材料配制的杂交组合的抗病性表明，杂交组合的抗病性均高于非转基因亲本，但其抗病性也会因母本的不同而有所变化。

关键词: 转基因水稻, 几丁质酶基因, 纹枯病, 抗病性