【摘要】 中红侧沟茧蜂Microplitismediator(Haliday)是夜蛾科害虫低龄幼虫的重要寄生蜂。田间实验表明,在冀中地区秋季田间条件下,当日平均气温为21.5℃、日平均光照时间为12h33min时,少数个体进入滞育;当气温降至17.9℃以下、日光照时间缩短到11h45min以下时,全部个体进入滞育。室内模拟实验结果表明,在17~26℃、光照时间10~14h范围内,随着温度的降低和光照时间的缩短,滞育率明显提高。高温能抵消短光照对滞育诱导的影响,在26℃下,短光照不能诱导滞育。因此,低温和短光照是诱导该种天敌昆虫滞育的主要因子。中红侧沟茧蜂感受滞育信号的敏感期为低龄幼虫期,以预蛹(茧)进入滞育。低龄幼虫感受滞育信号以后,需要在滞育环境中发育到老熟幼虫才能全部进入滞育。将室内诱导的滞育茧在4℃左右环境条件下冷藏240天,成蜂的羽化率和寄生能力与没有冷藏的非滞育茧差异不显著;冷藏300天,滞育茧仍有81.4%可以正常羽化。本项研究结果为中红侧沟茧蜂的规模化、标准化生产提供了科学的依据。更多还原

【Abstract】 Microplitis mediator (Haliday) is an important natural enemy to parasitize young larvae of some moths of Noctuidae (Lepidoptera). The results of field tests showed that in the middle region of Hebei province, when the daily average temperature was 21.5℃ and the daily average day length was 12 hours and 33 minutes, a few of M. mediator entered diapause. When the daily average temperature was below 17.9℃ and day length was shorter than 11 hours and 45 minutes, all of M. mediator entered diapause. The results of simulation test in the laboratory showed that when the temperature was between 17-26℃ and day length was 10-14 hours, the diapause rate significantly increased with the decrease of temperature and day length. High temperature counteracted the effect of short day length. When the temperature is 26℃, photoperiod had no effect on diapause. Thus, lower temperature and shorter day length were the major factors to induce diapause of the parasitoid. The parasitoid accepted the signal for diapause at the young larvae stage and entered diapause at the pre-pupa stage (cocoon). All pre-pupae entered diapause only if the young larvae had been reared in the temperature and the photoperiod for diapause induction till mature larvae. The emergence rate and the parasitic ability showed no significant difference between adults emerged from the diapause cocoons stored in the temperature of 4±2℃ for 240 days and those from the non-diapause cocoons without cold storage. After 300 days cold storage, the emergence rate of the diapause cocoons could still reach to 81.4%.更多还原