Description
| - Z osmi populací na čtyřech geograficky vzdálených lokalitách v Číně bylo v letech 2003 a 2004 získáno 461 izolátů Blumeria graminis f.sp. hordei. Jejich frekvence virulence byla zjišťována na 30 diferenciačních liniích. Žádný izolát nebyl virulentní ke genům rezistence Mla1, Mla3, Mla6, Mla7, Mla9, Mla12, Mla13, Mlat, Mlg, Mla10, Mla22, Mla23, Mlp1, Ml(N81) a Mlmw. V Evropě převládají virulence k prvním 9 genům rezistence a tvoří hlavní část genetické vzdálenosti mezi čínskými a evropskými populacemi. Na základě reakcí diferenciačních linií nesoucích geny Mlk1, Mlh, MlLa, Ml(Bw), Mlra a Ml(Ru2), byly identifikovány patotypy a vypočítány parametry diverzity. Úplná efektivnost genů rezistence, pro něž nebyly zjištěny žádné odpovídající virulence, umožní čínským šlechtitelům přístup k mnoha moderním evropským odrůdám ječmene, které jsou plně odolné k padlí travnímu v Číně včetně těch, které mají gen nehostitelské rezistence mlo. (cs)
- Four hundred and sixty-one isolates of Blumeria graminis f.sp. hordei were obtained from eight populations at four geographically distant locations in China during 2003 and 2004. Their virulence frequency was determined on 30 differential lines. No isolate was virulent to resistance genes Mla1, Mla3, Mla6, Mla7, Mla9, Mla12, Mla13, Mlat, Mlg, Mla10, Mla22, Mla23, Mlp1, Ml(N81) and Mlmw. Virulences to the first nine resistance genes are prevalent in Europe and constitute the main part of genetic distance between Chinese and European populations. Based on reactions of differential lines possessing the genes Mlk1, Mlh, MlLa, Ml(Bw), Mlra and Ml(Ru2), pathotypes were identified and diversity parameters calculated. Complete effectiveness of the resistance genes, for which no corresponding virulences were found, will allow Chinese breeders to access many modern European barley cultivars that are fully resistant to powdery mildew in China, including those possessing the nonhost resistance gene mlo.
- Four hundred and sixty-one isolates of Blumeria graminis f.sp. hordei were obtained from eight populations at four geographically distant locations in China during 2003 and 2004. Their virulence frequency was determined on 30 differential lines. No isolate was virulent to resistance genes Mla1, Mla3, Mla6, Mla7, Mla9, Mla12, Mla13, Mlat, Mlg, Mla10, Mla22, Mla23, Mlp1, Ml(N81) and Mlmw. Virulences to the first nine resistance genes are prevalent in Europe and constitute the main part of genetic distance between Chinese and European populations. Based on reactions of differential lines possessing the genes Mlk1, Mlh, MlLa, Ml(Bw), Mlra and Ml(Ru2), pathotypes were identified and diversity parameters calculated. Complete effectiveness of the resistance genes, for which no corresponding virulences were found, will allow Chinese breeders to access many modern European barley cultivars that are fully resistant to powdery mildew in China, including those possessing the nonhost resistance gene mlo. (en)
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