Bee Protection Center, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
Exp Appl Acarol. 2014 Jan;62(1):47-55. doi: 10.1007/s10493-013-9728-0. Epub 2013 Aug 24.
This study assessed the response of Apis mellifera to brood deliberately infested with Tropilaelaps mercedesae. The reproductive success of T. mercedesae in mite-inoculated and naturally infested brood was also compared. The presence of T. mercedesae inside brood cells significantly affected brood removal. Thai A. mellifera removed 52.6 ± 8.2 % of the brood inoculated with T. mercedesae as compared to 17.2 ± 1.8 and 5.7 ± 1.1 % removal rates for the groups of brood with their cell cappings opened and closed without mite inoculation and the control brood (undisturbed, no mite inoculation), respectively. Brood removal peaked during the second and third days post inoculation when test brood was at the prepupal stage. Overall, non-reproduction (NR) of foundress T. mercedesae was high. However, when NR was measured based on the criteria used for Varroa, the naturally infested pupae (NIP) supported the highest NR (92.8 %). Newly sealed larvae inoculated with Tropilaelaps collected from newly sealed larvae (NSL) had 78.2 % NR and those inoculated with Tropilaelaps collected from tan-bodied pupae (TBP) had 76.8 % NR. Since Tropilaelaps is known to have a short development period and nearly all progeny reach adulthood by the time of host emergence, we also used two Tropilaelaps-specific criteria to determine NR. Foundresses that did not produce progeny and those that produced only one progeny were considered NR. Using these two criteria, NR decreased tremendously but showed similar trends with means of 65, 40 and 33 % for NIP, NSL and TBP, respectively. High NR in the NIP group may indicate increased hygienic behavior in Thai A. mellifera colonies. The removal of infested prepupae or tan-bodied pupae will likely decrease the reproductive potential of Tropilaelaps. Our study suggests that brood removal may be one of the resistance mechanisms towards T. mercedesae by naturally adapted Thai A. mellifera.
本研究评估了蜜蜂对故意感染 Tropilaelaps mercedesae 的幼虫的反应。还比较了在有螨虫接种和自然感染的幼虫中 T. mercedesae 的繁殖成功率。T. mercedesae 存在于幼虫细胞内会显著影响幼虫的清除率。与未接种螨虫的幼虫组和对照组（未受干扰，未接种螨虫）相比，接种 T. mercedesae 的幼虫组的幼虫清除率为 52.6±8.2%，而仅打开和关闭幼虫细胞盖的幼虫组的幼虫清除率分别为 17.2±1.8%和 5.7±1.1%。幼虫接种后第 2 天和第 3 天幼虫处于预蛹期时，幼虫清除率达到峰值。总体而言，发现者 T. mercedesae 的非生殖（NR）率很高。然而，当根据用于 Varroa 的标准来衡量 NR 时，自然感染的蛹（NIP）支持最高的 NR（92.8%）。从新封盖的幼虫中接种 Tropilaelaps（NSL）的新封盖幼虫的 NR 为 78.2%，从棕褐色体蛹（TBP）中接种 Tropilaelaps 的 NR 为 76.8%。由于 Tropilaelaps 的发育周期较短，并且几乎所有后代在宿主出现时都已成年，因此我们还使用了两个 Tropilaelaps 特有的标准来确定 NR。未产生后代的发现者和只产生一个后代的发现者被认为是 NR。使用这两个标准，NR 大大降低，但趋势相似，NIP、NSL 和 TBP 的平均值分别为 65%、40%和 33%。NIP 组中的高 NR 可能表明泰国蜜蜂的卫生行为有所增加。清除受感染的预蛹或棕褐色体蛹可能会降低 Tropilaelaps 的繁殖潜力。我们的研究表明，幼虫清除可能是泰国自然适应的蜜蜂抵抗 T. mercedesae 的一种抵抗机制。
