水稻抗白叶枯基因的遗传多样性与分子进化

抗病基因进化就是新抗病专化性产生的过程。对水稻抗白叶枯基因Xa1和Xa21在近缘类群中耐雌渭岸杂易宄稍苯胁庑颍ü员雀鹘峁褂蛐蛄屑涞募罨婊环绞健⒚苈胱拥母谋淝榭觥⒆蜃拥姆植加胫掷嗟龋芯靠共』蛟谥旨渌降囊糯嘌裕髦刈椤⒀≡窈图且渥涞纫蛩氐淖饔眉岸嘌缘奈只疲治銎溆肟共∽ɑ约涞墓叵怠?..

Abstract:Plant resistance gene (R gene)and phytopathogen avirulence gene (avr gene).are co-evolved with a genetic ralationship named “gene-for-gene”. Owing ochromosome recombination, R genes and their gene families maintained high level of.genetic variation. With supporting of a short-term NSF fund, our study aimed at.revealing genetic diversity of rice bacteria-blight resistance gene Xa21 within genus Oryza. A bacterial chromosome library of rice are constructed, which consists of 33,792 clones, with average insertion length as 80 Kb and amounted to 6 X genome coverage. A primary Southern blot analysis of eight species of AA genome from Oryza genus, with Xa21 PCR fragment as probe, revealed that a number of Xa21 homologues exist. Further study is necessary to determine the detail and mechanisms behind it. Key words: Bacteria-blight resistance gene; Genetic diversity; Molecular Evolution;