抗二化螟的水稻品种筛选

Resistance of rice varieties to the stripe stem borer Chilo suppressalis

【目的】筛选抗二化螟Chilo suppressalis水稻品种资源,明确其抗虫机理,是农业防治的基础。【方法】采用室内人工接虫为害和大田自然受害相结合的方法,鉴定了不同的水稻品种抗性;同时通过目测不同水稻植株外部形态特征、在网罩内供试品种上接入成虫后2 d的产卵量、幼虫孵化后2 d观察稻株内二化螟的存活率,探讨抗虫品种的抗虫机理。【结果】从344个水稻品种资源和当家品种中筛选出"碑田倒"和"银间杂糯"2个抗虫品种,以及"农飞"和"三香糯"等65个中抗品种,进一步对鉴定出的2个抗虫品种和65个中抗品种进行大田验证,发现符合率达88.06%;其中,抗虫品种"碑田倒"和"银间杂糯"稻株叶舌、叶耳紧贴,叶鞘紧包,脉间距较窄,其植株上的产卵量和幼虫存活率显著少于感虫品种"香稻"、"赣南早"、"三粒寸"、"赣优晚"及中抗品种"赛湖早"、"TKM6"。【结论】在籼稻、粳稻和糯稻中均可筛选出抗虫和中抗品种。其中,糯稻中的抗虫品种和中抗品种较多,占糯稻品种的33.3%;粳稻品种次之,中抗品种占20%,籼稻品种较少,为18.83%。其抗虫机理主要是稻株外部形态特征不利于二化螟蚁螟侵入、成虫产卵量少和幼虫生长发育不良、存活率低。

[Qbjectives] The resistance levels and underlying mechanisms by which rice varieties resist attack by the stripe stem borer were investigated to provide the basis for rational utilization of rice varieties. [Methods] The resistance levels of rice varieties to Chilo suppressalis were evaluated following both artificial inoculation and natural infection with this pest. The resistance mechanism of resistant rice varieties to C. suppressalis were studied by surveying the external morphological characteristics of rice plants, egg numbers and larval survival rates of C. suppressalis. [Results] 2 resistant rice varieties and 65 moderately resistant rice varieties were selected from 344 rice varieties. Similarity of resistance of the above 67 rice varieties to C. suppressalis in the field and laboratory was 88.06%. Compared with susceptible rice varieties, the leaf ligule, auricle and leaf sheath of resistant rice varieties（Beitiandao and Yingjianzanuo） clung more tightly to the rice stem, the distance between leaf veins was narrower, and egg numbers and survival rates of C. suppressalis on resistant rice plant were lower. [Conclusion] Resistant and moderately resistant rice varieties were selected from indica type rice, japonica rice and glutinous rice. A relatively high proportion of resistant and moderately resistant rice varieties were glutinous rice varieties（33.3%）, moderately resistant rice varieties accounted for 20% of japonica rice and 18.83% of indica type rice. The anti-insect mechanism of rice varieties included morphological features of rice plants that protect against the boring activity of C. suppressalis. Eggs numbers and larval survival rates of C. suppressalis on resistant rice plants were lower than on susceptible varieties.