侵染狄斯瓦螨后西方蜜蜂的致畸等级划分

为明确狄斯瓦螨侵袭西方蜜蜂蜂群后工蜂出现的畸形等级和形态差异,参照1988年Ruttner提出的形态测定标准,测定了蜂螨侵袭后采集蜂巢内正常蜂、畸形蜂、爬行蜂的喙、翅、足、背、腹等躯干的形态特征值,划分西方蜜蜂的致畸等级。结果表明:畸形蜂的腿长(8.188±0.122)mm、蜡镜面积2.451 mm²、翅脉指数Ci(-0.501)小于其他3种蜂,畸形蜂的经济性能消失;爬行蜂的蜡镜面积3.072 mm²、第六腹板宽指数(93.686)最大,而背腿比(56.759)最小,从形态结构上来说,背部与腿部的比例失调可能造成了工蜂爬行;按累积贡献率>85%原则确定了蜂螨对工蜂致畸性的8个主要成分;聚类分析显示,爬行蜂在形态上不能与正常工蜂区分开,因素分析显示畸形蜂划分为3个等级:A型趋近正常工蜂;B型中度残缺,表现为翅膀残缺;C型重度残缺,翅膀、腹、腿完全畸形。蜂螨入侵后翅膀与腹部首先发生变化,表明这个部位具较强的脆弱性,出现不同程度的畸形可能是蜜蜂抗蜂螨的一种抗逆适应性的表现。

Malformation grade of western honeybee,Apis mellifera,infected by mite,Varroa destructor

In order to investigate the malformation grade and morphological difference of honeybee worker, Apis mellifera, infected by ectoparasitic mite, Varroa destructor, the honeybee morphologic value by Ruttner (1988) were referred to measure the size of proboscis, wings, hindleg, targit, sternit and then the malformation for foragers, normal younger bees, climbing bees and malformed bees was graded. The results showed that economic performance disappeared for malformed bees whose hind leg length (8.188±0.122) mm, area of wax mirror (2.451 mm²) and cubital index (-0.501) was less than normal young bees, foragers, climbing bees. The area of wax mirror (3.072 mm²), 1/width sternit 6(93.686) of climbing bees was more than others but the body size/leg (56.759) was the smallest. In terms of morphology and structure, the imbalance between the back and the legs may cause the crawling of worker bees. Eight major components for malformed bees were established by high than 85% accumulated contribution rates of correlated matrix. The cluster analysis didn't distinguish the climbing bees with normal bees and discriminated analysis revealed three grades for malformation workers in which A type was close to normal bees, B type was medium and had an incomplete wings, C type had complete absent wings and shortened the leg and abdomen. The wings and abdomen previous variations showed vulnerability and malformation grade that may reflect an adaptive stress tolerance for bee resisted to mite.