Greenberg S M, Sappington T W, Setamou M, Armstrong J S, Coleman R J, Liu T-X
Benficial Insect Research Unit, Kika dela Garza SARC-ARS-USDA, Weslaco, TX 78596, USA.
Environ Entomol. 2007 Apr;36(2):256-62. doi: 10.1603/0046-225x(2007)36[256:rpoofa]2.0.co;2.
The feeding and oviposition activity of overwintering boll weevils, Anthonomus grandis grandis (Boheman), and seasonal fluctuations in development, survival, and reproduction of progeny of overwintering and first- and second-generation boll weevil females were determined in the laboratory at 27 degrees C, 65% RH, and a photoperiod of 12:12 (L:D) h. During the cotton-free period in the Lower Rio Grande Valley, female boll weevils without access to cotton resorb their unlaid eggs and enter reproductive diapause. However, when they were provided daily with greenhouse-grown cotton squares, commencement of oviposition began after 7, 15, or 20 d, depending on when they were captured. Females captured later in the winter fed longer before laying eggs than those captured in the early fall, suggesting that it may take females longer to terminate diapause the longer they have been dormant. The rate of feeding by females was significantly less during the winter months, and this may have affected the rate of diet-mediated termination of dormancy. Females of the first and second generations after the overwintering generation produced a significantly higher percentage of progeny surviving to adulthood and a higher proportion of these progeny were females. Offspring development time from overwintering female parents was significantly longer than that from first and second generations under the same laboratory conditions. The total number of lifetime eggs produced by females of the second generation during the cotton-growing season were approximately 9.9-fold higher than for overwintering females and 1.5-fold higher than for first-generation females. Life table calculations indicated that the population of second-generation boll weevils increased an average of 1.5-fold higher each generation than for females of the first generation and 22.6-fold higher than for overwintering females. Our data showed variation in boll weevil survival, development, and reproductive potential among the overwintering and first- and second-generation females, suggesting inherent seasonal fluctuations in these parameters.
在27摄氏度、相对湿度65%以及光周期为12:12（光照:黑暗）小时的实验室条件下，测定了越冬棉铃象甲（Anthonomus grandis grandis (Boheman)）的取食和产卵活动，以及越冬、第一代和第二代棉铃象甲雌虫后代的发育、存活和繁殖的季节性波动。在下里奥格兰德河谷没有棉花的时期，无法接触到棉花的棉铃象甲雌虫会吸收未产下的卵并进入生殖滞育。然而，当每天给它们提供温室种植的棉蕾时，产卵在7、15或20天后开始，这取决于它们被捕的时间。冬季后期捕获的雌虫在产卵前取食的时间比初秋捕获的雌虫更长，这表明雌虫休眠的时间越长，终止滞育可能需要更长的时间。冬季月份雌虫的取食速率显著较低，这可能影响了饮食介导的休眠终止速率。越冬代之后的第一代和第二代雌虫产生的后代存活到成年的百分比显著更高，并且这些后代中雌虫的比例更高。在相同实验室条件下，越冬雌虫亲本的后代发育时间明显长于第一代和第二代。第二代雌虫在棉花生长季节产生的终生总卵数比越冬雌虫大约高9.9倍，比第一代雌虫高1.5倍。生命表计算表明，第二代棉铃象甲种群数量每代平均比第一代雌虫增加1.5倍，比越冬雌虫增加22.6倍。我们的数据显示，越冬、第一代和第二代雌虫之间棉铃象甲的存活、发育和繁殖潜力存在差异，表明这些参数存在固有的季节性波动。
