中华花翅跳小蜂生物学特性和种群动态的研究

Bionomics and population dynamics of Microterys sinicus Jiang (Hymenoptera: Encyrtidae)

中华花翅跳小蜂MicroteryssinicusJiang是白蜡虫成虫产卵期的主要天敌。该蜂成虫喜在自然光下活动 ,取食和交配都在寄主树上进行。中华花翅跳小蜂每雌平均怀卵量 34 39粒 ,产卵前期 2～ 3天。产卵量、产卵率和产卵天数与温度密切相关 ,2 7℃时产卵量和产卵率最高。 30℃时产卵天数最少。 2 1～ 2 7℃卵孵化率达 80 %以上。幼虫共 5龄。每头跳小蜂幼虫平均取食蜡虫卵数分别为 :1龄 14 6粒 ,2龄 2 9 8粒 ,3龄 6 9 4粒 ,4龄 12 6 9粒。 5龄幼虫不取食。全代发育起点温度和有效积温分别为 11 84℃和 5 74 32日·度。补充营养能显著延长成虫寿命和产卵天数 ,提高雌虫产卵量。中华花翅跳小蜂成虫在田间有两个高峰期 ,分别发生在 4月上中旬和 5月中下旬。每粒虫囊内跳小蜂幼虫数与白蜡虫健卵百分率呈负指数关系 ,拟合方程为 :Y =96 0 82 9Exp (- 0 1872x)。

The bionomics and population dynamics of Microterys sinicus Jiang, an important natural enemy of the white wax insect, Ericerus pela Chavannes, during the latter's oviposition period, were surveyed from 1995 to 1998 in Yunnan Province. It was found that the adults moved up and down host trees and fed on honeydew as supplementary nutrition. Copulation occurred on host trees. There were 34 39 ova in one female. The pre oviposition period was 2-3 days. 81 72% of the total eggs laid were laid during the 4th-10th day of oviposition. The egg numbers, percentage of eggs laid and duration of oviposition were closed related to temperature. The highest oviposition numbers and oviposition percentages occurred at 27℃, and the shortest oviposition period at 30℃. Hatchability was above 80% from 21℃ to 27℃. The larvae underwent 5 instars. The 1st-4th instar larva consumed 14 6, 29 8, 69 4 and 126 9 eggs of the white wax insect respectively. The 5th instar larva stopped feeding, excreted and pupated in the host body. Generation time became shorter as the temperature increased with the shortest generation time occurring at 27℃. Excessively high or low temperatures were unfavorable to the development of the wasp. The thermal threshold and thermal sum for larval development were 11 84℃ and 574 32 day degrees respectively. Supplementary nutrition could prolong adult lifespan, the duration of oviposition and increase female oviposition numbers remarkably. The first and middle ten days of April and the middle and last ten days of May were the peak periods of wasp abundance. The relationship between wasp quantities per ovisac and the percentage of health white wax insect eggs can be simulated with the index equation: Y=96 0829 Exp (-0 1872 x) .