豇豆荚螟幼虫的生物学特性研究

Biological Characteristics of the Bean Pod borer's Larvae

通过室内饲养和田间调查,研究了豇豆荚螟(Maruca testulalis Geyer)幼虫的生物学特性,结果表明:该虫在湖南长沙地区一年发生6～7代,幼虫共5龄。1～5龄幼虫头壳宽度分别为0.197±0.001、0.325±0.009、0.536±0.003、0.889±0.006、1.471±0.004mm,相邻头壳宽度比值约为1.64。在18℃时,1～5龄幼虫的历期分别是3.1±0.81、3.0±0.8、2.5±0.6、3.7±0.9和5.7±1.5d;在32℃时,1～5龄幼虫的历期分别为1.7±0.7、1.1±0.3、1.2±0.5、1.2±0.6、1.3±0.7d。幼虫期的发育起点温度是9.9℃,有效积温为187.2℃。

Biological characteristics of larvae of bean pod borer （Maruca testulalis Geyer） was studied by indoor feeding and field investigation. The results showed that bean pod borer had 6-7 generations per year in Changsha region. Bean pod borer＇s larvaes had 5 instars altogether. The helmet breadth of bean pod borer for the 1^st - 5^th instar larvaes were 0.197±0.001, 0.325±0.009, 0.536±0.003, 0.889±0.006, and 1.471±0.004 mm respectively, The ratio of the neighboring helmet breadths was 1.64. At 18℃, the developmental durations of the 1^st-5^th larvaes were 3.1 ±0.8, 3.0±0.8, 2.5±0.6, 3.7±0.9 and 5.7±1.5 d, respectively. At 32℃, those were 1.7±0.7,1.1±.3, 1.2±0.5, 1.2±0.6, and 1.3 ±0.7 d. The developmental threshold temperature of bean pod borer＇s larvaes was 9.9℃, and the effective accumulated temperature was 187.2℃.