转基因作物对天敌昆虫的影响是转基因生态安全研究的一个重要内容。本文通过室内试验,研究了黑肩绿盲蝽兼性取食褐飞虱蜜露和稻株伤流液可能带来的潜在生态风险。结果表明,黑肩绿盲蝽取食褐飞虱蜜露,雌、雄成虫寿命分别为75.9和67.5 d,比蒸馏水对照组显著延长,雌成虫捕食褐飞虱卵的能力为23粒/日,比蒸馏水对照下降;取食稻株伤流液的雌成虫寿命(58.1 d)延长,捕食能力(24.9粒/日)下降;无论黑肩绿盲蝽取食褐飞虱蜜露或稻株伤流液,转基因水稻Bar68-1对黑肩绿盲蝽成虫寿命(雌67.6 d,雄61 d)和捕食能力(24.9粒/日)的影响,与非转基因亲本对照D68和非转基因感虫对照TN1的一致。研究表明,兼性取食转基因抗除草剂水稻Bar68-1稻株伤流液和褐飞虱蜜露,没有给稻田重要捕食性天敌黑肩绿盲蝽增加新的生态风险。
The effect of genetically modified (GM) crops on natural enemies is an essential part of ecological safety assessment of GM crops. The potential risk of genetically modified herbicide-tolerant (GMHT) rice Bar68-1 on Cyrtorhinus lividipennis, a natural enemy for the brown planthopper (BPH) with facultative feeding on honeydew of BPH and bleeding sap of rice plants, was evaluated in the laboratory. Results showed that longevity of male (67.5 d) and female (75.9 d) adults of C. lividipennis fed on BPH honeydew was significantly longer than those in the BPH fed water only (control). The longevity of female adults fed on bleeding sap of rice plants (58.1 d) was prolonged, too. However, the number of BPH eggs preyed by C. lividipennis per day significantly decreased in female adult of C. lividipennis fed BPH honeydew (23) and bleeding sap of rice plants (24.9). The adult longevity (male 61 d, female 67.6 d) and predatory capacity (24.9 eggs preyed per day) of C. lividipennis fed GMHT rice Bar68-1 were not significantly different from those of the insects fed untransformed parental cultivar D68 or a BPH-susceptible rice variety, Taichung Native 1, whether C. lividipennis was fed plantbleeding sap or BPH honeydew. The results suggest that adult longevity and predatory capacity of C. lividipennis are not affected by GMHT Rice Bar68-1 regardless of its facultative feeding on BPH honeydew or plant bleeding sap, so the transgenic rice will not bring new ecological risks to one of the most important predators of BPH in rice ecosystem.