Zeng Xiao-Fang, Li Lei, Li Jian-Rong, Zhao De-Gang
The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Guizhou University, Guiyang, Guizhou, People's Republic of China.
The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education) Institute of Agro-Bioengineering and College of Life Sciences, Guizhou University, Guiyang, Guizhou, People's Republic of China.
Biotechnol Appl Biochem. 2016 Jan-Feb;63(1):77-85. doi: 10.1002/bab.1342. Epub 2015 Apr 24.
To produce new rice blast- and herbicide-resistant transgenic rice lines, the McCHIT1 gene encoding the class I chitinase from Momordica charantia and the herbicide resistance gene PAT were introduced into Lailong (Oryza sativa L. ssp. Japonica), a glutinous local rice variety from Guizhou Province, People's Republic of China. Transgenic lines were identified by ß-glucuronidase (GUS) histochemical staining, PCR, and Southern blot analyses. Agronomic traits, resistance to rice blast and herbicide, chitinase activities, and transcript levels of McCHIT1 were assessed in the T2 progeny of three transgenic lines (L1, L8, and L10). The results showed that the introduction of McCHIT1-PAT into Lailong significantly enhanced herbicide and blast resistance. After infection with the blast fungus Magnaporthe oryzae, all of the T2 progeny exhibited less severe lesion symptoms than those of wild type. The disease indices were 100% for wild type, 65.66% for T2 transgenic line L1, 59.69% for T2 transgenic line L8, and 79.80% for T2 transgenic line L10. Transgenic lines expressing McCHIT1-PAT did not show a significant difference from wild type in terms of malondialdehyde (MDA) content, polyphenol oxidase (PPO) activity, and superoxide dismutase (SOD) activity in the leaves. However, after inoculation with M. oryzae, transgenic plants showed significantly higher SOD and PPO activities and lower MDA contents in leaves, compared with those in wild-type leaves. The transgenic and the wild-type plants did not show significant differences in grain yield parameters including plant height, panicles per plant, seeds per panicle, and 1000-grain weight. Therefore, the transgenic plants showed increased herbicide and blast resistance, with no yield penalty.
为培育新的抗稻瘟病和抗除草剂转基因水稻品系，将编码来自苦瓜的I类几丁质酶的McCHIT1基因和抗除草剂基因PAT导入来自中华人民共和国贵州省的本地糯稻品种来隆（Oryza sativa L. ssp. Japonica）。通过β-葡萄糖醛酸酶（GUS）组织化学染色、PCR和Southern杂交分析鉴定转基因株系。在三个转基因株系（L1、L8和L10）的T2代中评估农艺性状、对稻瘟病和除草剂的抗性、几丁质酶活性以及McCHIT1的转录水平。结果表明，将McCHIT1-PAT导入来隆显著增强了除草剂抗性和稻瘟病抗性。用稻瘟病菌Magnaporthe oryzae感染后，所有T2代子代的病斑症状均比野生型轻。野生型的病情指数为100%，T2转基因株系L1为65.66%，T2转基因株系L8为59.69%，T2转基因株系L10为79.80%。表达McCHIT1-PAT的转基因株系在叶片丙二醛（MDA）含量、多酚氧化酶（PPO）活性和超氧化物歧化酶（SOD）活性方面与野生型没有显著差异。然而，接种稻瘟病菌后，与野生型叶片相比，转基因植株叶片中的SOD和PPO活性显著更高，MDA含量更低。转基因植株和野生型植株在株高、单株穗数、每穗粒数和千粒重等产量参数方面没有显著差异。因此，转基因植株表现出增强的除草剂抗性和稻瘟病抗性，且没有产量损失。
