rep-PCR法对稻瘟病菌有性后代随机群体的评价

摘要/Abstract

摘要： 构建稻瘟病菌有性后代随机群体是研究目的基因遗传特点，乃至克隆目的基因的重要基础，但是在建立有性后代随机群体时，可能会有无性后代污染。采用先分离单个子囊，待其长成菌落并产生分生孢子后，再分离单个萌发的分生孢子的方法构建稻瘟病菌有性后代随机群体。利用基于重复DNA序列Pot2的rep-PCR方法对分离得到的有性后代进行DNA指纹分析，并评价构建的稻瘟病菌有性后代群体的质量。结果表明，构建的有性后代随机群体共包含176个后代。每个后代个体的DNA指纹图谱均与两亲本的DNA指纹图谱不一致；有性后代之间的DNA指纹图谱也彼此不一样，说明得到的有性后代个体都是由子囊孢子萌发形成的，且分离自不同的子囊。GUY11的rep-PCR扩增片段中的5个特异性片段的分离比例也都符合1:1的期望值，是按单个位点标记分离的，与已知的结果相吻合，说明有性后代随机群体的质量较高，不存在偏离现象，是一个较为理想的群体。同时，研究结果还得出基于Pot2的rep-PCR方法可以用来快速评价稻瘟病菌有性后代群体的质量。

关键词: FSH, FSH, GC, MAPK, StAR

Abstract: The random population of ascospore progeny is highly important for genetic analysis or chromosome-walking based gene cloning of Magnaporthe oryzae, a fungal pathogen that causes disastrous rice disease. But the random ascospore progeny may be contaminated by conidia while conducting single ascus and ascospore isolation, which may result in a genetic bias. In this study, individual asci from a cross of strains GUY11 and 81278 were first isolated, then transferred to rice polish agar plates to grow and produce conidia for 3~5 d. Single conidium from each ascus was isolated to construct a random ascospore progeny population. DNA samples from the population and their parents were isolated and used to fingerprint by using Pot2 rep-PCR techniques. The results showed that 176 single conidia isolated from individual asci were different from their parents in DNA fingerprinting patterns, suggesting that each conidium is derived from a single ascospore, and all the progenies were isolated from individual asci. Furthermore, there were 5 specific amplified fragments segregated in 1:1 ratios, suggesting that these fragments are single-locus markers. The results further proved that the random ascospore progeny we constructed was of high quality for genetic analysis, and indicated that the Pot2 rep-PCR could be used as a rapid method for assessing the quality and estimating the deviation of the random ascospore progeny of M. oryzae.

中图分类号:

S435.111.41

王宝华,翁琴云,汤重淼,鲁国东,王宗华. rep-PCR法对稻瘟病菌有性后代随机群体的评价[J]. 中国农学通报, 2007, 23(12): 311-311.

Wang Baohua, Weng Qinyun, Tang Zhongmiao, Lu Guodong, Wang Zonghua. Assessment of the Random Ascospore Progeny of Magnaporthe oryzae by rep-PCR[J]. Chinese Agricultural Science Bulletin, 2007, 23(12): 311-311.

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