松褐天牛六种类型的触角感器的超微结构

Ultrastructure of six types of antennal sensilla in Monochamus alternatus

利用扫描电镜和透射电镜对松褐天牛Monochamus alternatus Hope不同类型触角感器的超微结构进行了观察和研究。在松褐天牛触角上存在6种类型的感器:机械感器、锥形感器、毛型感器、耳形感器、刺形感器和栓锥形感器。机械感器壁厚无孔,淋巴腔中无树突。锥形感器壁薄多孔,有50多个树突分支,每个分支有1～10个微管。毛型感器单壁,壁上有小孔,孔数相对较少,感器内树突1～8个不等,树突内含不同数量的微管。耳形感器,壁薄多孔,内部有少于5个的树突分支,树突内含有数量不等的微管。刺形感器又分为2个亚型:Ⅰ型壁上具纵脊无孔,顶端有孔;Ⅱ型壁上无脊无孔,顶端具单孔。刺形感器Ⅰ型和Ⅱ型均壁厚无孔,树突鞘一直通到顶端小孔。栓锥形感器上半部具纵脊无孔,下端有少量孔,顶端具三瓣状开口的孔。对感受器功能的讨论认为:机械感器不是化学感器;锥形、毛型和耳形感器是嗅觉感器;刺形和栓锥形感器可能是接触化学(味觉)感器。

The ultrastructure of different types of antennal sensilla in Monochamus alternatus Hope was investigated by scanning and transmission electron microscopy.There were six types of sensilla on its antenna,i.e.mechanoreceptor,sensilla basiconica,sensilla trichodea,sensilla auricillica,sensilla chaetica and sensilla styloconica.There was thick wall and no dendrite in mechanoreceptor.There was thin cuticular wall perforated by numerous pores in sensilla basiconica,and more than 50 dendritic branches,each of which contained 1-10 microtubules.Sensilla trichodea were single-walled with relatively fewer pores,and there were 1-8 dendrites,each of which contained different amount of microtubules.There was thin cuticular wall perforated by numerous pores in sensilla auricillica,and less than 5 dendritic branches,each of which contained different amount of microtubules.There were two subtypes in sensilla chaetica,in which subtype I showed grooved surface and no pores,but terminal pores,and subtype II showed no grooved surface and pores,as well as a terminal pore.There was thick non-porous wall in both subtypes,and dendrite sheath up to terminal pore.There were lengthways veins and no pores on the upside of sensilla styloconica,several pores on the downside,and a trifurcate terminal pore.The functions of sensilla were discussed that mechanoreceptor was not chemical sensilla,and sensilla basiconica,sensilla trichodea and sensilla auricillica were olfactory sensilla,but sensilla chaetica and sensilla styloconica were possibly gustatory sensilla.