Cohen Michael B, Bernal Carmencita C, Virmani Sant S
Entomology and Plant Pathology Division, International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines.
J Econ Entomol. 2003 Dec;96(6):1935-41. doi: 10.1093/jee/96.6.1935.
Antibiosis-based resistance to two insect pests of rice, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), was compared in 11 F1 hybrids and their parental lines. Our objective was to determine whether hybrids show heterosis (hybrid vigor) for insect resistance or susceptibility. Heterosis is defined as the amount by which a hybrid exceeds its midparent value or its better parent. Overall, we did not find evidence of heterosis or heterobeltiosis (a type of heterosis in which a hybrid exceeds its better parent) for antibiosis-based resistance or susceptibility to either of the insects. One hybrid, IR64616H, seemed more resistant to M. patnalis than its better parent but none of the other hybrids showed heterobeltiosis for resistance or susceptibility to either insect. Three hybrids had resistance to N. lugens that exceeded their midparent value, possibly due to dominant resistance in one of the parents. The increased frequency and severity of insect outbreaks on hybrid rice that have been reported in China may be attributable to factors other than diminished antibiosis in hybrids, such as greater attractiveness of hybrids to migrating or dispersing insects or differences in agronomic practices applied to hybrids and inbred rice cultivars.
在11个F1杂交种及其亲本系中，比较了基于抗生作用对两种水稻害虫的抗性，这两种害虫分别是褐飞虱（Nilaparvata lugens (Stål)，半翅目：飞虱科）和稻纵卷叶螟（Marasmia patnalis Bradley，鳞翅目：螟蛾科）。我们的目的是确定杂交种对昆虫的抗性或易感性是否表现出杂种优势（杂交活力）。杂种优势定义为杂交种超过其双亲平均值或其较好亲本的数值。总体而言，我们没有发现基于抗生作用对这两种昆虫的抗性或易感性存在杂种优势或超亲优势（杂种优势的一种，其中杂交种超过其较好亲本）的证据。一个杂交种IR64616H对稻纵卷叶螟的抗性似乎比其较好亲本更强，但其他杂交种对这两种昆虫的抗性或易感性均未表现出超亲优势。三个杂交种对褐飞虱的抗性超过了它们的双亲平均值，这可能是由于其中一个亲本具有显性抗性。在中国报道的杂交水稻上昆虫爆发频率和严重程度增加，可能归因于杂交种抗生作用降低以外的其他因素，例如杂交种对迁飞或扩散昆虫的吸引力更大，或者应用于杂交种和自交水稻品种的农艺措施存在差异。
