紫外线胁迫对红色型豌豆蚜生物学特性的影响

由于臭氧层消耗,南北半球中高纬度地区紫外线(UV-B)胁迫增强,为了探求增强的UV-B胁迫对红色型豌豆蚜生物学特性的影响,以期明确UV-B辐射在豌豆蚜种群演替和种下分化中的作用。本研究以40 W紫外线灯连续辐射处理红色型豌豆蚜8代,每代从初产若蚜开始每天处理1次,连续照射6d,分20、30、40、50和60min 5个处理,并设置白炽灯对照。结果显示,同一世代,随着UV-B辐射时间延长,豌豆蚜体长逐渐减短,体重逐渐减轻,净增殖率、内禀增长率、周限增长率逐渐减小,平均世代周期逐渐延长。同一UV-B辐射时间下,随着世代增加,豌豆蚜体长、体重、净增殖率、内禀增长率、周限增长率均呈先上升后显著下降的趋势,平均世代周期呈先下降后显著上升的趋势。至F8代,不同辐射时间下豌豆蚜平均体长为对照的42.58%~81.94%,平均体重为对照的33.77%~73.12%,净增殖率为对照的6.94%~46.55%,周限增长率为对照的77.00%~87.94%,平均世代周期为对照的1.20~1.38倍,内禀增长率降低,且50~60min处理下小于对照的1/2,种群数量增长放缓。以上说明长期UV-B胁迫对豌豆蚜的生长发育和种群增长最终都有抑制作用。

Effects of UV-B stress on biological characteristics of red peaaphid Acyrthosiphon pisum Harris

The depletion of ozone resulted in enhanced UV-B stress in middle and high latitudes of the northern or southern hemisphere. These situations generally made genetic divergence of aphids. This study sought to determine the effects of UV-B stress on biological properties of the red pea aphid and on species succession and subspecies differentiation. The newly born red pea aphids were treated for 8 generations by 40 W UV-B radiation, once a day, 6 times at 20 min, 30 min, 40 min, 50 min and 60 min. The results indicated that, with UV-B radiation time prolonged, the average body length of red pea aphids cut back, with average weight lightened, net reproductive rate, finite rate of increase and intrinsic rate reduced, and the mean generation time was prolonged in the same generation. Continuous UV-B radiation made average body length, average weight, net reproductive rate, finite rate of increase and intrinsic rate all increase in the first four generations, then reduce greatly with generation increasing, but the mean generation time declined at first, then increased. Up to F8, the average body length, average weight, net reproductive rate, finite rate of increase and mean generation time were 42.58%-81.94%, 33.77%-73.12%, 6.94%-46.55%, 77.00%-87.94%, and 1.20-1.38 times of the CK.However, the intrinsic rate decreased to 1/2 of the CK under the treatments of 50 min and 60 min, indicating that the population quantity was negative increase. All these data suggested that a long period of UV-B stress might lead to inhibitory effects on development and population growth of the red pea aphid.