134份四川小麦品种(系)的条锈病抗性评价

小麦条锈病是四川小麦生产中的第一大病害。为了系统掌握四川小麦品种和后备品系的条锈病抗性水平,给四川乃至全国小麦抗条锈病育种及品种的合理布局提供参考信息,利用7个条锈菌流行小种对134份四川审定品种和后备品系的苗期和成株期条锈病抗性进行鉴定。结果表明,四川小麦品种(系)在苗期对7个条锈菌小种CYR31、Su11-7、CYR29、Su11-4、CYR32、CYR33和V26(新致病类型)的抗性频率分别为92.4%、92.5%、89.3%、89.4%、87.3%、85.0%和82.8%;其中,76份品种(系)抗所有小种,占56.0%;此外,条锈菌新致病类型V26对四川小麦品种(系)的毒性已经超过当前的优势小种CYR32和CYR33。根据抗谱分析结果,将所有品种(系)分为四大类。其中,66.4%的品种(系)为全生育期抗性,17.9%为成株期抗性,9.7%表现为苗期抗性,6.0%表现为感病。表明四川小麦品种(系)整体抗性水平较高,但抗病类型相对单一。因此,需要进一步拓宽抗源,提高抗病基因的多样性;同时应逐步开展全生育期抗病基因和成株期抗病基因聚合育种,以提高品种抗病的持久性。

Evaluation of Resistance to Stripe Rust of 134 Wheat Cultivars and Lines from Sichuan Province

Stripe rust,caused by Puccinia striiformis Westend. f. sp. tritici Erikss. (Pst),is one of the most destructive diseases of wheat (Triticum aestivum L.) worldwide. Sichuan province plays an important role in stripe rust epidemic in China. To identify and evaluate the resistance to stripe rust in wheat of Sichuan province,134 wheat cultivars and lines were inoculated at seedling stage with seven Pst isolates in greenhouse and at adult stage with mixed races in field. The results indicated that frequencies of resistance to seven isolates of CYR31,Su11 7,CYR29,Su11 4,CYR32,CYR33 and V26 were 92.4%,92.5%,89.3%,89.4%,87.3%,85.0% and 82.8%,respectively. Among the 134 materials,76 (56.0%) were effective against all tested Pst isolates both in seedling and adult stages. The virulence of new Pst isolate V26,which is virulent on Yr24/ Yr26,was stronger than the predominant races CYR32 and CYR33. The 134 wheat cultivars and lines were classified into four clusters according to their reaction patterns to 7 isolates,and 66.4% of them showed all stage resistance,17.9% were adult plant resistance,9.7% were seedling stage resistance and 6.0% were susceptible. It is showed that the type of resistance was simplification although the resistance levels of wheat cultivars and lines were very high. Therefore,it is important to identify new resistant genes and enhance the diversity of resistant genes,and pyramiding all stage resistance with adult plant resistance in cultivars to achieve durable resistance to stripe rust in Sichuan province.