銀葉粉蝨在胡瓜上之族群介量

Population parameters of Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae) on cucumber

取食胡瓜之雌、雄性銀葉粉蝨（Bemisia argenti olii Bellows & Perring）於19.4日-19.9日內自卵發育為成蟲，雌雄間的發育期差異不顯著。發育期間之死亡率達27.5％；雌蟲壽命為25.0日，產卵前期則甚短（1.2日）；於22.5日之產卵期內可產90.4卵，每日每雌平均可產3.59卵，其產卵高峰出現於第4及第8日（6.78及6.14卵／雌／日），較年輕的雌成蟲日產卵量較高。子代性比雌性高於雄性（♀♀/（♀♀+♂♂）=0.69）。銀葉粉蝨取食胡瓜時，於世代時間（T= 28.3日）可增殖90.08倍（R_o），每日每雌之理論內在增殖率（r_m）達0.159子代／雌／日。銀葉粉蝨之齡別繁殖潛能（R）顯示因胡瓜植株老化（senescenc），會導致粉蝨向外遷移。穩定年齡分佈（C）揭示，年輕發育期之粉蝨佔族群之比例較高。經與往昔研究相比較之結果顯示，胡瓜品種之不同、溫度、光強度、寄主植物營養及雌蟲交尾次數等因子，均會造成銀葉粉蝨族群介量的差異；而銀葉粉蝨於不同胡瓜品種之適應策略，係依發育速率及成蟲壽命而非繁殖率。

"Both male and female silverleaf whitefly (SLWF), Bemisia argenti olii Bellows & Perring, feeding on cucumber of the Fon-yen variety, completed immature duration in 19.4 and 19.7 days, respectively, with a 27.5% mortality rate. Adult females lived an average of 25.0 days with a short preoviposition period (1.2 days) and laid 90.4 eggs in 22.5 days of the oviposition period, with a rate of 3.64 eggs/female/day. The peak reproduction rate was found at either day 4 (6.78 eggs/female/day) or day 8 (6.14 eggs/female/day). Younger females produced a larger amount of offspring than did aged ones, and the offspring sex ratio (♀♀/(♀♀ + ♂♂)) of the SLWF favored the female (0.69). The SLWF population increased 90.08-fold in a mean generation time of 28.3 days with an intrinsic rate of increase of 0.159 eggs/female/day. The stage-specific reproduction potential (Rx) of SLWF showed that the population moved out of its habitat when the host was senescent. A stable age distribution (C) showed that juveniles were the majority among the age groups that comprised the SLWF population. We also discuss the influences of the variety of cucumber, temperature, light intensity, host nutrient level, and frequency of copulation by the female on the development and growth of the SLWF. The strategies used by the SLWF for host adaptation, if not for all kinds of host then at least in cucumbers, are the developmental rate of immatures and adult longevity instead of the reproduction rate."