Effects of relative humidity on cocoon formation and survival in the braconid wasp Cotesia glomerata
Effects of relative humidity on cocoon formation and survival in the braconid wasp Cotesia glomerata
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相对湿度对茧蜂 Cotesia glomerata 结茧和存活的影响
DOI：
10.1111/j.1365-3032.2008.00635.x
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Y. Satoh
中科院分区：
文献类型：
--
作者：
J. Tagawa;Y. Satoh
相对湿度（RH）对小茧蜂（Cotesia glomerata， L.）成茧及存活的影响在不同湿度条件下（50、75、90、95和100% RH），在20°C和ld16: 8 h的光周期下进行研究（膜翅目：小蜂科）。在100% RH条件下，离宿主时的死亡率显著高于其他RH条件。在100%相对湿度下形成的茧团比在50、75或90%相对湿度下形成的茧团传播得明显更多。在不同的RHs下，黄蜂的发育周期有显著差异。在50-95%相对湿度条件下，从寄主迁移到成虫羽化的平均时间为8.7 d，在100%相对湿度条件下为8.0 d。在相同湿度条件下，离寄主后保持的羽化率在不同区域间无显著差异。然而，从100% RH转移到50%和75% RH的茧的羽化率< 70%，尽管大多数情况下羽化率为90%以上。有些黄蜂不会破茧而出：60%以上的黄蜂在成虫羽化后死亡；在50% RH条件下，成人死亡的相对频率约为90%。相对湿度对茧团和结茧状态影响较大，在较低的RHs条件下都能形成良好的团和茧。不同等级茧的羽化率有显著差异：低RHs时低等级茧的羽化率较低。RH通过茧的形成强烈地影响了C. glomerata的存活。
Abstract The effects of relative humidity (RH) on cocoon formation and survival in the braconid parasitoid wasp Cotesia glomerata (L.) (Hymenoptera: Braconidae) are investigated under various humidity conditions (50, 75, 90, 95 and 100% RH) at 20 °C and under an LD 16 : 8 h photoperiod. The mortality rate at the time of egression from hosts under 100% RH is significantly higher than for other RHs. Cocoon clusters formed at 100% RH spread significantly more than those formed at 50, 75, or 90% RH. Developmental periods differ significantly among RHs under which wasps developed. The mean period from the egression from hosts to adult emergence is 8.7 days when developed at 50–95% RHs, and 8.0 days at 100% RH. The emergence rates of C. glomerata that are maintained under the same humidity conditions after egression from hosts are not significantly different among RHs. However, emergence rates from cocoons that are transferred from 100% RH to 50 and 75% RH are < 70%, although the rates are > 90% in most cases. Some wasps do not emerge from cocoons: more than 60% die after adult eclosion at all RHs; the relative frequency of adult deaths is approximately 90% at 50% RH. Relative humidity influences the cluster and cocoon status strongly: both good clusters and cocoons are formed at low RHs. Emergence rates from cocoons of different ranks are significantly different: the rates of low‐rank cocoons are low at low RHs. The survival of C. glomerata is affected strongly by RH through cocoon formation.