Evolution of the wheat blast fungus through functional losses in a host specificity determinant
Evolution of the wheat blast fungus through functional losses in a host specificity determinant
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DOI：
10.1126/science.aam9654
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发表时间：
2017-07-07
期刊：
影响因子：
56.9
通讯作者：
Tosa, Yukio
中科院分区：
文献类型：
--
作者：
Inoue, Yoshihiro;Vy, Trinh T. P.;Tosa, Yukio
小麦稻瘟病最早于20世纪80年代中期出现在巴西，最近在亚洲造成了严重的作物损失。在这里，我们展示了这种毁灭性的病原体是如何在巴西进化的。通过对稻瘟菌寄主决定因素的遗传分析，克隆了无毒基因PWT3和PWT4，其基因产物在含有相应抗性基因Rwt3和Rwt4的小麦品种中诱导防御。对无毒和抗性基因分布的研究，以及巴西小麦种植的历史数据表明，小麦稻瘟病的出现是由于rwt3小麦(对Lolium分离物敏感)的广泛传播，随后是PWT3功能的丧失。这表明rwt3小麦是寄主向普通小麦跳跃的跳板。
Wheat blast first emerged in Brazil in the mid-1980s and has recently caused heavy crop losses in Asia. Here we show how this devastating pathogen evolved in Brazil. Genetic analysis of host species determinants in the blast fungus resulted in the cloning of avirulence genes PWT3 and PWT4, whose gene products elicit defense in wheat cultivars containing the corresponding resistance genes Rwt3 and Rwt4. Studies on avirulence and resistance gene distributions, together with historical data on wheat cultivation in Brazil, suggest that wheat blast emerged due to widespread deployment of rwt3 wheat (susceptible to Lolium isolates), followed by the loss of function of PWT3. This implies that the rwt3 wheat served as a springboard for the host jump to common wheat.