红脂大小蠹雄性配偶选择行为及其对生殖的影响

为研究红脂大小蠹(Dendroctonus valens)雄性能否依据信息素对雌性进行选择,以及这种选择行为对生殖的影响,首先使用Y-型嗅觉仪验证这种选择行为,然后用玻璃夹板技术分析雄性对其选择(P)和未选择(NP)的雌性在求偶和交配行为上的差异,最后用木段接种技术研究雄性与P雌性和NP雌性配对后在坑道构筑、产卵和幼虫发育上的差异。结果表明,雄性对雌性有着显著的基于信息素的选择行为。在求偶和交配行为上,雄性对P雌性更易求偶成功,交配时间更长(P0.05)。当雄性和P雌性配对时,前10 d筑出更长的且更清洁的坑道(P0.05)。20 d时,P雌性后代中孵化幼虫占后代总数量的比例极显著高于NP雌性(P0.001)。30 d时,P雌性的幼虫质量极显著高于NP雌性(P0.001)。以上结果表明,红脂大小蠹存在基于信息素的雄性配偶选择行为,其对生殖产生显著影响。

Effects of Male Mate Choice on the Reproduction of Dendroctonus valens

To investigate whether males of Dendroctonus valens could choose females according to pheromones,and effects of the selection behavior on reproduction,we used Y-tube olfactometer to validate this selection behavior,and used phloem sandwich experiments to test whether male mate preferences affected courtship displays by allowing males to mate with preferred (P)and nonpreferred (NP)females,respectively.We also used bolt inoculation experiments to validate the differences in egg gallery,oviposition,and larval development when males were paired with P females and NP females,respectively.The results showed that males could choose females based on pheromones.Males paired with P females improved the compatibility of courtship interaction,and the duration of copulation (P ＜0.05).When males were paired with P females,males and females constructed larger and cleaner galleries during the first 10 days after gallery initiation (P ＜ 0.05).P females had an overall higher proportion of larvae to eggs when compared to P females at 20 days(P ＜ 0.001),and the larvae of P females also had higher weights at 30 days(P ＜0.001).In a word,Dendroctonus valens had a behavior of male mate choice based on pheromones,which affected reproduction significantly.