Tagle Analiza Grubanzo, Chuma Izumi, Tosa Yukio
Graduate School of Agricultural Sciences, Kobe University, Kobe 657-8501, Japan.
Phytopathology. 2015 Apr;105(4):495-9. doi: 10.1094/PHYTO-06-14-0182-R.
A single gene for resistance, designated Rmg7 (Resistance to Magnaporthe grisea 7), was identified in a tetraploid wheat accession, St24 (Triticum dicoccum, KU120), against Br48, a Triticum isolate of Pyricularia oryzae. Two other wheat accessions, St17 (T. dicoccum, KU112) and St25 (T. dicoccum, KU122), were also resistant against Br48 and showed a similar disease reaction pattern to St24. Crosses between these resistant accessions yielded no susceptible F2 seedlings, suggesting that St24, St17, and St25 carry the same resistance gene. Furthermore, a single avirulence gene corresponding to Rmg7 was detected in a segregation analysis of random F1 progenies between Br48 and MZ5-1-6, an Eleusine isolate virulent to St24 at a higher temperature. This avirulence gene was recognized not only by St24, but also by St17 and St25, thus supporting the preceding results indicating that all three accessions carry Rmg7. This resistance gene may have potential in future wheat breeding programs.
在四倍体小麦材料St24（二粒小麦，KU120）中鉴定出一个抗稻瘟病基因，命名为Rmg7（抗稻瘟病菌7），该基因对稻瘟病菌的一个小麦分离株Br48具有抗性。另外两个小麦材料St17（二粒小麦，KU112）和St25（二粒小麦，KU122）对Br48也具有抗性，并且与St24表现出相似的病害反应模式。这些抗性材料之间的杂交未产生感病的F2幼苗，这表明St24、St17和St25携带相同的抗性基因。此外，在Br48与MZ5-1-6（在较高温度下对St24具有毒性的穇属分离株）的随机F1后代的分离分析中，检测到一个与Rmg7对应的无毒基因。这个无毒基因不仅被St24识别，也被St17和St25识别，从而支持了之前的结果，即这三个材料都携带Rmg7。这个抗性基因可能在未来的小麦育种计划中具有潜力。
