Yoshioka Motohiro, Kishii Masahiro, Singh Pawan Kumar, Inoue Yoshihiro, Vy Trinh Thi Phuong, Tosa Yukio, Asuke Soichiro
Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan.
International Maize and Wheat Improvement Center (CIMMYT), Mexico City, Mexico.
Phytopathology. 2024 Sep;114(9):2113-2120. doi: 10.1094/PHYTO-01-24-0018-R. Epub 2024 Sep 12.
Wheat blast, caused by (syn. ) pathotype (MoT), is a devastating disease that can result in up to 100% yield loss in affected fields. To find new resistance genes against wheat blast, we screened 199 accessions of , the D genome progenitor of common wheat (), by seedling inoculation assays with Brazilian MoT isolate Br48 and found 14 resistant accessions. A synthetic hexaploid wheat line (Ldn/KU-2097) derived from a cross between the 'Langdon' (Ldn) and resistant accession KU-2097 exhibited resistance in seedlings and spikes against Br48. In an F population derived from 'Chinese Spring' × Ldn/KU-2097, resistant and susceptible individuals segregated in a 3:1 ratio, suggesting that the resistance from KU-2097 is controlled by a single dominant gene. We designated this gene . Genetic mapping using an F population from the same cross mapped the locus to the short arm of chromosome 2D. was ineffective against Bangladesh isolates but effective against Brazilian isolates. Field tests in Bolivia showed increased spike resistance in a synthetic octaploid wheat line produced from a cross between common wheat cultivar 'Gladius' and KU-2097. These results suggest that would be beneficial in farmers' fields in South America.
小麦稻瘟病由（同义词：）致病型（MoT）引起，是一种毁灭性病害，在受影响的田块中可导致高达100%的产量损失。为了寻找抗小麦稻瘟病的新基因，我们用巴西MoT分离株Br48对普通小麦（）的D基因组祖先199份材料进行了苗期接种试验，发现了14份抗性材料。由“Langdon”（Ldn）与抗性材料KU-2097杂交得到的一个人工合成六倍体小麦品系（Ldn/KU-2097）在幼苗和穗期对Br48表现出抗性。在由“中国春”×Ldn/KU-2097衍生的F群体中，抗性和感病个体以3:1的比例分离，这表明来自KU-2097的抗性由一个单显性基因控制。我们将该基因命名为。利用同一杂交组合的F群体进行遗传定位，将位点定位到2D染色体短臂上。对孟加拉国分离株无效，但对巴西分离株有效。在玻利维亚的田间试验表明，普通小麦品种“Gladius”与KU-2097杂交产生的人工合成八倍体小麦品系的穗抗性增强。这些结果表明，在南美洲的农田中会对农民有益。
