Abstract: The resistance of Chinese japonica rice Chunjiang 06 (CJ-06) to the whitebacked planthopper (WBPH), Sogatella furcifera, was studied in compared with the susceptible hybrid rice Shanyou 63 (SY-63). Results showed that CJ-06 was highly resistant to WBPH. WBPH immigrants rejected to land and failed to establish colonies on CJ-06, while they preferred to settle and well reproduced on SY-63. Under a free-choice experimental condition, significantly fewer WBPHs alighted on CJ-06 than on SY-63. A WBPH female excreted only 4.8 mg honeydew per day on CJ-06, while 17.4 mg on SY-63, indicating a significantly suppressed sucking activity of WBPH on CJ-06. Both fecundity and egg hatchability were markedly reduced on CJ-06, when newly emerged WBPH females continuously fed and were allowed to oviposit in it. Average number of eggs laid in CJ-06 and SY-63 was 42.4 and 133.6, and percentage of egg hatchability was 20.1% and 64.5%, respectively. Consequently, the number of nymphs hatched on CJ-06 amounted to only about one-tenth of that on SY-63. WBPH eggs showed a high mortality in watery lesions at oviposition sites of CJ-06. The watery lesions rapidly led to the formation of conspicuous necrotic symptoms before the eggs hatched. The egg mortality occurred within 1-2 days after oviposition. Such watery lesions seldom occurred on SY-63, where the eggs hatched normally. Based on the above findings, it was concluded that sucking inhibition and ovicidal reaction were critical factors for WBPH resistance in CJ-06. These functions were associated with the antixenosis mechanism against WBPH immigrants, as well as the antibiosis mechanism whereby fecundity and egg hatchability of inhabitants were reduced, respectively. Such dual mechanisms of varietal resistance could result in the stable and durable field resistance to WBPH in the Chinese japonica rice CJ-06.

Key words: whitebacked planthopper, varietal resistance, japonica rice, sucking inhibition

摘要： 与感虫杂交稻汕优63相比较，研究了具有抗性的中国粳稻春江06对白背飞虱的抗性。结果表明，春江06高抗白背飞虱。迁入的白背飞虱拒绝在春江06上着陆，也不能在其上繁殖种群；而白背飞虱更趋向于在汕优63上定居，并繁殖良好。在自由选择的试验条件下，选择春江06的白背飞虱数量显著地低于选择汕优63的。白背飞虱在春江06上平均每天每只雌成虫分泌的蜜露量仅为4.8 mg，而在汕优63上为17.4 mg，表明春江06明显抑制白背飞虱的取食活动。如果让刚羽化的白背飞虱在春江06上连续取食和产卵的话，其产卵能力和卵孵化能力明显降低。白背飞虱在春江06和汕优63上的平均产卵量分别为每只雌成虫42.4个和133.6个，孵化率分别为20.1%和64.5%；在春江06上孵化出的若虫数量只有在汕优63上的10%左右。白背飞虱卵在春江06的水渍状产卵部位有很高的死亡率。在卵孵化之前，水渍状褐变部位迅速形成坏死症状。卵死亡出现在产卵后的1~2 d内。这样的水渍状褐变则极少发生在卵孵化正常的汕优63上。根据以上的发现，可总结出在春江06对白背飞虱的抗性中，抑制取食和杀卵作用是关键的因素。这些作用分别与对迁入白背飞虱的忌避性机理、与居留型白背飞虱产卵能力和卵孵化能力下降的抗生性机理相关。这种品种抗虫性的双抗机理使得粳稻品种春江06具有了稳定和持久的田间抗虫性。

关键词: 白背飞虱, 品种抗虫, 粳稻, 拒食抗性, 杀卵抗性