湖南水稻主推品种对旱稻孢囊线虫的抗性及评价方法

【目的】旱稻孢囊线虫是一种水稻上重要的病原线虫。筛选抗虫种质资源对抗病品种的选育至关重要。【方法】通过室内二龄幼虫接种和田间自然病圃鉴定,以单株平均孢囊数、相对抗病指数和繁殖系数法评价了湖南省51个主推的水稻品种对旱稻孢囊线虫的抗性。【结果】在供试水稻品种中未发现有免疫和高抗品种。室内接种条件下,在24个中稻品种中,依据单株平均孢囊数评价,仅广两优2010表现为抗;依据相对抗病指数评价,广两优2010、准两优527、广两优1128 3个品种为抗;在27个晚稻品种中,依据单株平均孢囊数评价,盛泰优9712、准两优608、农香优204、岳优9264、岳优3700、中浙优1号、岳优27、湘晚糯1号、贺优50、Y两优9918共10个品种为抗;而依据相对抗病指数评价,湘晚糯1号、贺优50、Y两优9918表现为中感。在田间自然病圃条件下,依据繁殖系数Pf/Pi评价,筛选出9个晚稻抗性品种,鉴定结果与室内接种相对抗病指数法基本一致。【结论】室内接种相对抗病指数法可以作为评价水稻品种对旱稻孢囊线虫抗性的有效方法。

Resistance to Heterodera elachista and Evaluation Methods of Major Rice Varieties from Hunan Province,China

【Objective】Heterodera elachista is a new pathogenic nematode of rice. In order to screen the resistant rice cultivars to H. elachista, 【Method】 51 rice varieties from Hunan Province were evaluated by the second-stage juvenile inoculation test in greenhouse and field with average number of cysts per plant, relative resistance index (RRI) and Pf/Pi ratio as indicators. 【Result】No rice cultivar was immune or highly resistant to H. elachista. Among the 24 middle-season rice cultivars, only Guangliangyou 2010 showed resistance to H. elachista based on average number of cysts per plant, and Guangliangyou 2010, Zhunliangyou 527 and Guangliangyou 1128 showed resistance to H. elachista based on RRI evaluation in greenhouse. Among the 27 late rice varieties, Shengtaiyou 9712, Zhunliangyou 608, Nongxiangyou 204, Yueyou 9264, Yueyou 3700, Zhongzheyou 1, Yueyou 27, Xiangwannuo 1, Heyou 50 and Y Liangyou 9918, were resistant to H. elachista based on average number of cyst per plant. However, Xiangwannuo 1, Heyou 50 and Y liangyou 9918 were moderately susceptible based on RRI evaluation. Using Pf/Pi ratio as the evaluation index, nine late resistant varieties screened from greenhouse based on RRI evaluation were basically consistent with field resistance. 【Conclusion】RRI is an efficient index for evaluating the resistance of rice cultivars to rice cyst nematode.