Nishizawa Y, Nishio Z, Nakazono K, Soma M, Nakajima E, Ugaki M, Hibi T
National Institute of Agrobiological Resources, 2-1-2,Kannondai , Tsukuba, 305-8602, Japan, JP.
Theor Appl Genet. 1999 Aug;99(3-4):383-90. doi: 10.1007/s001220051248.
Rice blast is the most devastating plant disease in Japan. Our goal is to create new rice varieties which show enhanced resistance against blast, regardless of the race of blast. By an Agrobacterium-mediated transformation method, we reintroduced a rice class-I chitinase gene, Cht-2 or Cht-3, under the control of the enhanced CaMV 35S promoter and a hygromycin phosphotransferase gene, as a selection marker into the Japonica rice varieties Nipponbare and Koshihikari, which have retained the best popularity over a long period in Japan. In regenerated plants (R(0)), the Cht-2 product was found to accumulate intracellularly whereas the Cht-3 product was found to be targeted extracellularly. The transgenic rice plants which constitutively expressed either chitinase gene showed significantly higher resistance against the rice blast pathogen Magnaporthe grisea races 007.0 and 333. Both high-level expression of the chitinase and blast-resistance were stably inherited by the next generation in several lines.
稻瘟病是日本最具毁灭性的植物病害。我们的目标是培育出对稻瘟病具有更强抗性的新型水稻品种，且这种抗性不依赖于稻瘟病菌株的生理小种。通过农杆菌介导的转化方法，我们将一个水稻I类几丁质酶基因Cht - 2或Cht - 3，在增强型CaMV 35S启动子的控制下，以及作为选择标记的潮霉素磷酸转移酶基因，重新导入到日本粳稻品种日本晴和越光中，这两个品种在日本长期以来一直广受欢迎。在再生植株（R(0)）中，发现Cht - 2产物在细胞内积累，而Cht - 3产物则靶向细胞外。组成型表达任一几丁质酶基因的转基因水稻植株对稻瘟病菌生理小种007.0和333表现出显著更高的抗性。几丁质酶的高水平表达和抗稻瘟病能力在多个株系的下一代中都得到了稳定遗传。
