Assessment of the Random Ascospore Progeny of Magnaporthe oryzae by rep-PCR

Abstract

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.

CLC Number:

S435.111.41

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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