禾谷孢囊线虫(cereal cyst nematode,CCN)是一类重要的土传小麦病原线虫,危害我国小麦的主要是燕麦孢囊线虫(Heterodera avenae)和菲利普孢囊线虫(H.filipjevi)。我国对这些病原线虫的抗性资源十分缺乏,寻找新抗源是当前抗性育种的重要工作。本研究通过3年的田间病圃和温室接种鉴定,发现加拿大的硬粒小麦品种Waskana和Waskowa对H.filipjevi(河南许昌群体,Hfc-1致病型)和H.avenae(河南荥阳群体,Ha43致病型)都表现很强的抗性,单株孢囊数显著少于感病的普通小麦品种矮抗58、石4185和温麦19。显微观察可见,虽然2种线虫的幼虫都能够侵入Waskana和Waskowa的根组织内,但是根内的线虫数量显著少于感病对照普通小麦品种,最终在根系上形成的可见孢囊数量也较少。Waskana和Waskowa对2种病原线虫的抗性为我国抗CCN小麦品种选育提供了有较高利用价值的新抗源。根据南澳大利亚研究所的土传病害检测服务系统对土壤中病原线虫的分子检测结果,抗CCN品种Waskana和Waskowa根际土壤中的线虫虫卵量低于感病小麦品种,因此种植后可能降低土壤中禾谷孢囊线虫危害的风险。
Cereal cyst nematodes (CCN) are a group of important soil-borne pathogens of wheat. Heterodera avenae and H. filip- jevi are the major species of CCN that have limited wheat (Triticum aestivum) production in China in recent years. Since the CCN-resistant resource is short, it is important to develop new sources with resistance for breeding purpose in China. Based on the results of a 3-year field test and controlled environment tests, we found that two Canadian Triticum durum cultivars, Waskana and Waskowa, were highly resistant to both Heteroderafilipjevi (pathotype Hfc-1) and H. avenae (pathotype HA43) populations from Henan Province, China. The number of white females per plant in Waskana and Waskowa was significantly smaller than that in the susceptible common wheat cultivars Aikang 58, Shi 4185, and Wenmai 19. Although the juveniles of H. filipjevi and H. avenae populations were able to penetrate into the roots of Waskana and Waskowa, the," number of juveniles inside the roots was significantly smaller than that of Aikang 58, Shi 4185, and Wenmai 19, resulting in smaller numbers of females on the roots of these durum wheat cultivars. Waskana and Waskowa with resistance to H. filipjevi and H. avenae are useful in developing wheat cultivars with enhanced resistance to CCN in China. Based on the results from the DNA-basecl soil tesung swrvice operated by South Australian Research and Development Institute, the number of eggs of nematodes in the rhizospheric soil samples from the CCN-resistant cultivars Waskana and Waskowa was less than that in the soil samples from the susceptible wheat cultivars. This indicates that application of resistant cultivars might reduce the risk of damage caused by CCN in soil.