籼稻A232及其RILs对三化螟产卵的抗性

Evaluation of indica rice A232 and its derived RILs on resistance to Tryporyza incertulas(Walker)

【目的】明确不同水稻基因型对三化螟Tryporyza incertulas(Walker)产卵的抗性差异,为抗螟材料的育种利用提供依据。【方法】以5个对照品种及10个冈46B×A232的RILs为材料,在海南自然条件下通过灯诱三化螟雌蛾产卵,比较不同基因型间落卵量的差异。【结果】三化螟雌蛾卵块在水稻基因型间呈聚集分布,A232、TTP、F77及RILs C22-230、C22-174、C22-113、C22-133的聚集均数(λ)值<2,对雌蛾产卵具有一定的驱避性。基因型间的叶片卵块指数及分蘖卵块指数均达显著或极显著差异,冈优188的叶片及分蘖卵块指数分别是A232的6.1倍及5.7倍。C22-99的叶片及分蘖卵块指数是C22-113的2.7倍及3.3倍。A232、TTP及C22-113对雌蛾产卵及幼虫取食均具有一定抗性。聚类分析将15个供试材料分为倾抗虫亲本A232和倾感虫亲本冈46B两大类。【结论】水稻基因型间对三化螟产卵的抗性存在显著差异,筛选评价抗螟种质应将对幼虫为害抗性与对雌蛾产卵抗性结合起来。

[Objectives] To identify genotypes of rice resistant to Tryporyza incertulas（Walker） for the selective breeding of more resistant strains. [Methods] Female T. incertulas moths were attracted by light traps to 5 control varieties of rice and 10 RILs derived from Gang 46 B ×A232 under natural conditions on Hainan Island. Oviposition on rice plants was statistically analyzed among different the different rice genotypes. [Results] Egg masses were aggregated on rice plants. The aggregation average（lambda） value was 2 in the three control varieties（i.e. A232, TTP and F77） and 4 RILs（i.e. RILs C22-230, C22-174, C22-113 and C22-133）, suggesting that these lines are somewhat repellent to ovipositing female moths. Egg mass abundance, as assessed by both leaf and tiller indices, were significantly different among rice genotypes（P0.05 and 0.01, respectively）. Leaf and tiller egg mass indices for Gangyou 188 were 6.1 times and 5.7 higher, respectively, than in A232. Leaf and tiller egg mass indices in C22-99 were 2.7 times and 3.3 higher, respectively, than in C22-113. Our data revealed that the A232, TTP and C22-113 rice strains were relatively resistant to female moth oviposition and larval feeding. We subsequently divided the 15 rice lines into two types on the basis of their similarity to the resistant parent A232, or the susceptible parent, Gang 46 B. [Conclusion] Resistance to female moth oviposition was significantly different among different rice genotypes tested. It is necessary to consider resistance to both larval damage and female moth oviposition to evaluate the overall resistance of rice varieties to T. incertulas.