雅脊金小蜂长翅型雌蜂对米象种群的控制作用

Control effectiveness of long-winged Theocolax elegans (West.) against rice weevil, Sitophilus oryzae (L.)

雅脊金小蜂Theocolax elegans（West．）是我国南方重要仓储害虫米象Sitophilus oryzae（L．）的优势天敌。为了更好地保护和利用该蜂，采用单因子方差分析和ISD多重比较，在实验室内研究了雅脊金小蜂和米象的种群数量动态，以及该蜂长翅型雌蜂对米象种群的控制作用。结果显示，在温度25℃、相对湿度65％的条件下，雅脊金小蜂和米象的世代发育历期分别约为25天和40天。按照每盒1、2、4、8、16、32、64和128头接入的寄生蜂均可定殖，并对米象种群起着控制作用。其中，接蜂64头时，即寄生蜂与米象数量比为1：6时，控制效果最好，在放蜂后第10-50天内，控制效果迭89．11％-96．47％，与其它几组试验差异显著。试验结果表明，雅脊金小蜂可以有效地控制米象的发生与危害。

Theocolax elegans （ West. ） is a predominant parasitoid of Sitophilus oryzae （ L. ） in South China. In order to the conservation and utilization of this wasp, laboratory studies were conducted to assess the population dynamics of them and effectiveness of the long-winged parasitoid wasps, T. elegans for suppressing populations of S. oryzae using methods for single element variance analysis and LSD multiple comparisons. The population dynamics of T. elegans and S. oryzae showed that the developmental duration of them for one generation were 25 days and 40 days respectively at 25℃, 65% RH. The control experiment revealed that the released female wasps at different density of 1,2, 4, 8, 16, 32, 64 and 128 per box all can colonize and play an important natural control effect on rice weevil. When 64 female adults of T. elegans were inoculated in wheat, which the ratio between wasps and rice weevil was 1 to 6, the control effectiveness is the best, and the control effectiveness could reach 89.11% -96.47% after 10 to 50 days from initial wasp release, which show significant difference from the others. These results suggested that T. elegans could effectively control the occurrence and damage of S. oryzae under laboratory condition.