嗜卷书虱高CO_2抗性品系的选育及其适合度研究(英文)

室内恒温条件下以人工饲料饲养的嗜卷书虱 Ｌｉｐｏｓｃｅｌｉｓ ｂｏｓｔｒｙｃｈｏｐｈｉｌａ Ｂａｄｏｎｎｅｌ成虫，分别在３５％和５５％ＣＯ_２。（２１％Ｏ_２，Ｎ_２作为平衡气体使用）组配的气调环境中以７０％的选择压力处理，以选育其抗高ＣＯ_２气调性。选育至３０代获得抗性品系ＨＣＣ_１和ＨＣＣ_２，以ＬＴ_５０为标准，其抗性倍数分别达４．６和５．３倍。整个选育过程中，气调暴露时间对数值与死亡率机率值间的回归直线基本平行，且斜率值均低于敏感基线的斜率值，这表明嗜卷书虱对高ＣＯ_２抗性发展的基因潜能至第３０代仍未耗尽。两个抗性品系的抗性均不太稳定，去除选择压力后抗性显著下降，且两抗性品系均具有繁殖不利性即适合度缺陷。以净增值率为指标衡量，ＨＣＣ_１和ＨＣＣ_２相对于敏感品系分别具有０．５２和０．４５的适合度。

SELECTION OF RESISTANCE STRAINS IN LIPOSCELIS BOSTRYCHOPHILA BADONNEL TO CO_2-ENRICHED ATMOSPHERES

Adults of the psocid Liposcelis bostr ychophila Badonnel were exposed to atmospheres contain- ing 35% and 55% CO_2 for 30 generations to select strains resistant to high CO_2, content (HCC). Selection pressure was maintained at around 70% of mortality. At the 30th generation, comparison of sensitivities between the selected strains (HCC_1 and HCC_2) and the original susceptible strain (MA-S) revealed a resis- tance factor (RF) at the 50% mortality level (LT_50) of 4. 6-and 5. 3-folds, respectively. Throughout the selection process, log-time against probit-mortality lines remained roughly parallel and the slopes remained lower than that of MA-S strain until the last generation. It is inplied that the genetic potential of L. bostrychophila to develop resistance to CO_2 was not exhausted until the 30th generation. Removal of selec- tion pressure for 5 generations from 2 sub-populations of two selected strains from the 25th generation caused significant reduction in resistance. In the absence of MAs exposure, the two selected strains (HCC_1 and HCC_2) possessed the fitness defect. HCC_1 and HCC_2 were calculated by R_o to have a fitness value of 0. 52 and 0. 45 relative to MA-S.