湿度对橘小实蝇及寄生蜂存活与发育的影响

Survival and development of Psyttalia incisi and its host Bactrocera dorsalis under different relative humidities

研究外来入侵害虫橘小实蝇及其寄生蜂在不同湿度条件下的存活与发育能力,以预测其在福建的适生分布区。结果表明:在25℃条件下,不同相对湿度对切割潜蝇茧蜂成蜂种群寿命影响大小依次为75%>95%>55%>35%,其中75%相对湿度下种群平均寿命最长,采用二次曲线模型并求得最适相对湿度为75.2%;不同相对湿度对橘小实蝇种群寿命的影响大小依次为75%>55%>95%>35%,采用二次曲线模型并求得最适相对湿度为68.7%,二者可能具有相似的分布区域。同时,从存活曲线分布的情况来看,切割潜蝇茧蜂在不同湿度下的存活曲线分布较橘小实蝇更集中,表明橘小实蝇对湿度的变化表现出更强的敏感性。同时,湿度低于35%时,不能交配并繁殖后代;处于较高湿度时,对其后代体形大小没有显著影响。

The ability of Bactrocera dorsalis （Hendel）, and its parasitoid, Psyttalia incisi（ Silvestri）, to survive and develop under different relative humidities （35%, 55%, 75%, 95% ） at 25℃ was studied to predict potentialclimatic limitations to their establishment in Fujian and indicate whether the parasitoid has different climatic tolerance compared to its host population at all experimental conditions. Adult survival was evaluated under relative humidities maintained by saturated solutions. The sequence of effect on the longevity of P. incisi was 75% 〉95% 〉55% 〉35% and P. incisi survived longer at 75% RH than any other relative humidities, while that of B. dorsalis was 75% 〉55% 〉95% 〉35%. Which suggested both of them had a lower net water loss rate at ＂r5% RH. The relationship between the survival and RH was both simulated to get the optimal RH, they were 75.2% for P. incisi, and 68.7% for B. dorsalis, suggesting the moisture requirements for these two population are considerable. What＇ smore, the density of survival curve of P. incisi was denser than that of B. dorsalis, suggesting P. incisi was more susceptive to change of relative humidities than B. dorsalis. In addition, the female couldnt mate the male under lower relative humidity （35%）, while different higher relative humidities hadn＇t remarkable impact on the size of next generation.