【作者】 许永玉；

【导师】 胡萃； 牟吉元；

【作者基本信息】 浙江大学 ， 农业昆虫与昆虫防治， 2001， 博士

【摘要】 中华通草蛉Chrysoperla sinica（Tjeder）是蚜虫、叶螨和鳞翅目卵和低龄幼虫等多种农林害虫的重要天敌，是害虫生物防治中极具应用价值的一种天敌昆虫。该虫以成虫进行兼性滞育越冬，本文首次较系统地研究了中华通草蛉成虫滞育的生理及生态机制，同时还对该虫的测报和幼虫的捕食行为进行了初步研究。研究结果如下。1 中华通草蛉的发生消长和影响越冬成虫存活的生态因素 在山东省泰安地区，中华通草蛉在自然界世代重叠较为明显，越冬代成虫在越冬后种群数量稀少，6月份之前，自然界成虫的种群数量一直较少。6～9月间，在农田、果园和山区等环境中相继出现四次成虫高峰，其中6月份在果园和9月份在大叶黄杨苗圃中的两次成虫高峰最为明显。成虫越冬场所，在平原地带，主要为农田周围的林木苗圃和低矮的树林及果园的落叶中，麦田中没有发现越冬成虫；在丘陵地带，主要为向阳低矮的灌木丛及松柏树冠等环境中。 中华通草蛉越冬成虫在其越冬环境中的存活率较低，只有10％～20％，影响越冬成虫存活的主要因素是温度、湿度和食物。室外越冬环境中的试验表明，利用较密闭的器具贮存越冬成虫和越冬前后成虫能够获得充足的食物可明显提高成虫的存活率。室内不同温、湿度对越冬成虫存活影响的结果表明，当温度为5～9℃和相对湿度为70％～85％时，有利于成虫的存活，贮存5个月的存活率可达50％以上；温度和湿度过高或过低均不利于成虫的存活。2 中华通草蛉成虫滞育的生态机制 室内、外的研究表明，中华通草蛉属短日照滞育型昆虫；在自然界，组成越冬种群的成虫主要为第四代成虫和少量的第三、五代成虫；成虫滞育的敏感虫态主要是成虫期，三龄幼虫、预蛹和蛹的短光照经历对成虫滞育的形成也具有促进作用。在15℃、20℃、25℃和27℃下，诱导成虫滞育的临界光周期分别处于13L∶11D和14L∶10D、12.5L∶11.5D和13L∶11D、12L∶12D和12.5L∶11.5D、11L∶13D和12L∶12D之间；影响成虫滞育的主要因素为光周期和温度，光周期起决定性的作用。 中华通草岭成虫期一直保持着对诱导滞育短光照的敏感性，而且对光周期表现出明显的数量反应和循环反应特性，即不同光周期诱导的滞育成虫的滞育深度和滞育发育时间不同；尽管滞育成虫在滞育发育后期较短时间内失去对光周期的敏感性，但在解除滞育开始产卵后很快又恢复了对短光照的敏感性。 温度不是影响中华通草岭成虫滞育的关键因素，但能调节光周期对成虫滞育的作用效果，较低的温度能促进滞育的形成，降低滞育的发育速度，而较高的温度则起到相反的作用。结果表明，温度与成虫的滞育发育速度存在明显的线性相关关系，在光周期为gL；15D下，滞育成虫的发育始点为12．4℃，有效积温为785．4日度。低温对成虫滞育的解除没有促进作用。 食物对成虫滞育的发育过程没有明显的影响，但在成虫解除滞育后，食物是成虫生殖活动当即启动的重要影响因子。3中华通草玲成虫滞育的生理生化机制 滞育成虫在许多方面同非滞育成虫表现出很大的差异。中华通草岭成虫的滞育征候群主要有；滞育雌虫的卵巢发育明显受到抑制，最终呈萎缩且透明状，无卵黄沉积，滞育雄虫主要表现为精巢长度缩短，附腺明显萎缩，储精囊中无精子。滞育成虫体内脂肪细胞明显膨大，其内有大形脂滴；飞行肌退化。在代谢特征上主要表现为体内脂肪和糖原的含量明显提高，呼吸代谢速率明显下降，体内含水量也明显降低。成虫体色由绿色变为土黄色，体背出现红褐色的滞育斑，研究表明成虫体色的不同变化与成虫滞育的开始、结束以及滞育的深度有着密切的联系，成虫体色的变化可以做为判断成虫滞育的一个重要标志。 中华通草蛤成虫滞育与耐寒能力间的关系研究表明，成虫的耐寒不是滞育征候群的组成部分，低温锻炼才能明显提高成虫的耐寒能力。结果表明成虫的滞育和耐寒在自然界越冬过程中同时发生，并分别由光周期和温度来控制和调节。 中华通草岭成虫滞育的内分泌调控机制的研究表明，保幼激素（JH）是调节成虫生殖和滞育的重要内源激素，JH滴度在滞育成虫体内明显低于非滞育成虫，通过点滴外源保幼激素或保幼激素类似物可刺激成虫卵黄的沉积和卵的形成。脑的超微结构观察结果说明，滞育成虫脑神经分泌细胞的活性明显低于非滞育成虫。 皿 ／。4中华通草岭的测报和幼虫的捕怵为 根据中华通草蚌雌性生殖系统解剖学特征，将其发育分为5级，并以各级卵巢主要生化成份含量变化加以验证。该分级用于麦田测报结果表明，田间卵量与3级和4级卵巢所占比例具有很大的相关性。当雌虫生殖系统发育至3级的个体达50％以上时，3～4d后，田间雌成虫进入产卵高峰，当发育至4级的个体达50％以上时，雌虫进入产卵末期。这一测报方法可以试行。 中华通草?更多还原

【Abstract】 The lacewing, Chrysoperla sinica (Tjeder) was known as an important natural enemy attacking agriculture and forestry pests like aphids, mites and eggs, young larvae of lepidopterous insects, and a good biological control agent. This species overwintered as adults, but only a few studies had been done to investigate the termination of adult diapause. This paper mainly dealt in details with the ecological, physiological and biochemical mechanism of adult diapause in natural and experimental conditions. Egg forecasting in the field by the method of developmental grading of female reproductive system and larvae searching behavior were also preliminarily studied. The main results were summarized as follows.1. Population fluctuations of Chrysoperla sinica and Effects of Ecologic-al Factors on the Survival Rate of Overwintering AdultsIn Tanshan district of Tai-an, the phenomenon of C. sinica generation overlapping was obvious in the field; this species overwintered as diapausing adults in nature. The adult population was rare in spring, and remained low until the end of May. Four adult peaks occurred from June to September in the agricultural fields, orchard, and mountainous region, especially the adult peaks in orchard in June and in nursery garden of Euonymus joponicus in September were much distinct. In the plain area, overwintering C. sinica adults were found in the nursery garden, woods and leaves in orchard around agricultural fields. In hilly region, overwintering adults were found in the south- and east-facing low clumps of shrub and the crowns of pine and cypress.The survival rate of overwintering C. sinica adults in their natural overwintering site was much low, only about 10%~20%, the major ecological factors affecting survive of overwintering adults were temperature, relative humidity and food. The survival rate of adults hi natural overwintering site could be enhanced by the methods of collecting and storing them in the relative airtight implements and providing them sufficient foods before and after overwintering. Studies on the effects of temperature and relative humidity (RH) on the survive of overwintering adults collected from outdoor hi laboratory showed that 5*C ~ 9"C and RH 70% ~ 85% were the favorable storing conditions, under above conditions, the survival rate of overwintering adults was above 50% after five months storage. Temperature below 5 癈 and RH lower than 70% or higher than 90% could reduce the survival rate.2. Ecological Mechanism of Adult diapause of Chrysoperla sinicaThe studies indoor and outdoor showed that the C. sinica exhibited a facultative adult diapause induced under a short-day photoperiod, diapause was induced and terminated reversibly by photoperiodic changes between short-day (diapause-inducing) and long-day (diapause-preventing) conditions. In field, The overwintering population consisted mainly of adults of the fourth generation and of a small amount of the third and fifth generation. The photoperiodic sensitive stage was adult,and short-day experience of the third instar larvae, prepupa, pupa could promote the induction for adult diapause . At 15 "C ,20 癈 ,25 癈 ,and 27 癈 ,the critical daylenths for the induction of diapause were between 13hr and 14hr,12.5hr and 13hr , 12hr and 12.5hr ,llhr and 12hr, respectively . The primary factors affecting the adult diapause were photoperiod and temperature, and the key factor was photoperiod .Photoperiodic sensitivity persisted throughout the adult life. The diapausing adults showed clearly a quantitative photoperiodic response that different photoperiod have thus different quantitative effects on both the initial intensity of diapause and the rate of diapause development, and a recurrent photoeriodic response that adults could resume response to the diapause-promoting photoperiod after they terminated diapause and had a short period of oviposition. In post-diapause, diapausing adults lost sensitivity to photoperiod.Temperature wasn’t the key factor controlling the adult diapause of C. sinica, but更多还原