中红侧沟茧蜂滞育临界光周期和敏感光照虫态的测定

室内对中红侧沟茧蜂Microplitis mediator滞育诱导的光周期反应及敏感光照虫态进行了研究。结果表明：在16℃和18℃温度下,当光周期为10L∶14D时,中红侧沟茧蜂的滞育率最高为98%和87.8%;其次是光周期为8L∶16D时,滞育率为78.7%和73%;光周期为12L∶12D时,滞育率为55.8%和50.8%;而在全光照LL, 光周期22L∶2D,20L∶4D,18L∶6D,16L∶8D,14L∶10D ,2L∶22D和全黑暗DD时的滞育率均为0。中红侧沟茧蜂属于典型的长日照发育型,在16℃时诱导滞育的临界光周期是7.03L∶16.97D和12.21L∶11.79D;在18℃时是6.75L∶17.25D和12.03L∶11.97D。16℃时中红侧沟茧蜂对光照反应最敏感时期为2龄幼虫第5～8天,2龄幼虫第1～4,9～12和13～16天及3龄期次之,卵期和1龄幼虫不敏感。     

光周期对梨小食心虫滞育诱导的影响

在实验室条件下对梨小食心虫滞育诱导的光周期反应和不同日龄幼虫对滞育诱导光周期的敏感性进行了研究。结果表明:梨小食心虫属于典型的短日照滞育型,在20℃条件下,当光周期为8L ∶ 16D,10L ∶ 14D和12L ∶ 12D时,梨小食心虫的滞育率均达95%以上,诱导滞育的临界光周期为13.75L ∶ 10.25D;在24℃条件下,当光周期为10L ∶ 14D和12L ∶ 12D时,滞育率均达95%以上,诱导滞育的临界光周期为13.68L ∶ 10.32D。在幼虫期,分别给不同日龄幼虫以12L ∶ 12D和16L ∶ 8D光照处理后,在不同发育时间内幼虫对滞育诱导光周期反应均显示出一定程度的敏感性,无明显的临界时间点,但仍以第5-8日龄幼虫接受滞育诱导光周期反应更为敏感。     

草地螟阿格姬蜂的滞育诱导和滞育茧的低温贮藏

为了阐明环境因子对草地螟阿格姬蜂Agrypon flexorium (Thunberg)滞育诱导作用, 测定了5个光周期和4个温度处理对阿格姬蜂的滞育诱导和该蜂感受光周期的敏感虫态以及不同时间段低温贮藏对滞育虫茧的影响。结果表明： 在17~23℃、 光照时间10~14 h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草地螟阿格姬蜂滞育的主要因子。草地螟阿格姬蜂感受滞育信号的敏感虫态为卵和1龄幼虫。卵和1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80 d, 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120 d, 滞育茧仍有71.7%可以正常羽化。结果说明,可在17℃,光周期8L∶16D条件下对寄生后3 d内的草地螟Loxostege sticticalis幼虫进行滞育诱导, 滞育后的虫茧最佳贮藏时间为80 d, 不宜超过120 d。本研究为室内扩繁、 防止蜂源退化、 控制寄生蜂发育时间以便适时释放提供了参考依据。     

烟蚜茧蜂滞育诱导的温光周期反应

烟蚜茧蜂Aphidius gifuensis Ashmead是可持续防控蚜虫的优良内寄生蜂,在害虫生防中具有重要作用,研究其滞育对探索发育调控机制、延长产品货架期、提高防治效果意义重大。本文采用梯度变温法和光周期反应曲线法,系统研究了温度和光周期对烟蚜茧蜂滞育诱导的影响,研究结果表明:烟蚜茧蜂以老熟幼虫滞育,滞育类型属冬滞育型。低温、短光照是诱导烟蚜茧蜂滞育的主要环境因子,二者相互配合能诱导更多个体滞育。短光照(L∶D=8∶16)条件下,温度低于12℃可诱导烟蚜茧蜂进入滞育,8℃时滞育率可达54.35%。长光照(L∶D=14∶10)下,高温不能诱导烟蚜茧蜂滞育,低温下的滞育率较低,仅为1.79%。低温(10℃)下,短光照(8 h)可诱导50.70%的高滞育率,光照为14 h和6 h其滞育率均显著下降。25℃时,不同光照下滞育率均为0,光周期作用不显著。综合而言,温度和光周期均能显著影响烟蚜茧蜂的滞育,温度较光周期的滞育诱导效能更显著,二者互作配合能极显著的诱导烟蚜茧蜂进入滞育态。     

光周期对大草蛉(Chrysopa pallens)滞育及发育的影响

在22℃条件下,研究大草蛉对光周期的敏感性,结果表明:大草蛉属短日照滞育型,在短光照条件下饲养获得的预蛹进入滞育状态,诱导预蛹滞育的临界光周期为10.5L-13.5D到11L-13D.2龄幼虫期是诱导预蛹滞育的敏感虫期,只有当2龄幼虫期处于短光照条件下时才能进入滞育状态.1龄和3龄幼虫期也在滞育诱导条件下进行滞育诱导,能够提高滞育率.光周期对大草蛉幼虫历期及预蛹重的影响研究结果表明:光周期对幼虫历期有一定的影响,特别对2龄幼虫期的影响比较明显.幼虫期的光周期条件影响预蛹的重量,滞育预蛹的重量显著高于非滞育预蛹.     

黄杨绢野螟滞育诱导及光温反应

为了探讨黄杨绢野螟Diaphania perspectalis(Walker)越冬滞育特性,在自然条件与室内恒温下对黄杨绢野螟滞育诱导的光周期反应与光敏感龄期进行了研究。结果表明:该虫的光周期反应属于长光照反应型,短光照是引起黄杨绢野螟幼虫滞育的主要因子。幼虫的光周期反应对温度敏感,在恒温25℃和28℃条件下,诱导滞育的临界光周期分别为13h36min和12h50min。在日平均温度为26.7℃条件下,诱导滞育的临界光周期为13h40min。在恒温25℃条件下的滞育敏感虫龄试验表明,2～3龄幼虫即孵化后4～9d的幼虫对光周期反应最敏感。     

光周期和温度对草地螟滞育诱导的影响

草地螟Loxostege sticticalis以老熟幼虫滞育越冬。在室内通过人工诱导的方法对其滞育的光周期和温度诱导条件进行了研究。结果表明:草地螟是一种典型的长日照发育型种类。光周期、温度及其交互作用均对草地螟滞育诱导具有重要影响, 其中光周期起主导作用, 温度伴随着光周期起作用。对幼虫滞育诱导最有效的光周期是L12∶D12; 随着温度的升高, 临界光周期呈缩短趋势（18℃除外）。18, 22, 26和30℃条件下幼虫滞育的临界日长依次为13.97, 14.48, 13.92 和12.88 h。光敏感实验揭示:21℃时草地螟对光照反应最敏感时期为幼虫孵化后的11～17 d（约5龄幼虫）, 但孵化后7～11 d（约4龄幼虫）的短光照积累对提高滞育率也有重要作用, 可以将滞育率从40.0%提高到90.0%。     

中华通草蛉滞育的光周期调控Ⅰ.诱导成虫滞育的临界光周期和临界光照虫态(英文)

在22℃条件下,研究中华通草蛉对光周期的敏感性,结果表明:中华通草蛉属短日照滞育型,在短光照条件下饲养获得的成虫进入滞育状态,诱导成虫滞育的临界光周期为12.5小时到13小时。成虫期本身是诱导成虫滞育的最关键虫期,只有当羽化的成虫处于短光照条件下时才能进入滞育状态。成虫期之前其它虫期的短光周期经历能延长成虫在长光照条件下的产卵前期。三龄幼虫和预蛹期比成虫期前的其它虫期对光周期的变化更为敏感。     

大猿叶虫夏滞育的诱导：基于定量的光周期反应

为了探明大猿叶虫Colaphellus bowringi Baly夏滞育诱导的光周期时间测量特性, 我们通过室内实验系统比较了该虫在25℃、 不同长光照条件下,夏滞育的发生以及诱导50%个体进入夏滞育所需求的光 暗循环数。结果表明：不同长光照诱导的夏滞育比率有显著差异, 其中15 h或16 h光照诱导的滞育比率最高, 短于或长于这两个光照其滞育率均明显下降。在不同光 暗循环实验中, 14 h诱导的滞育比率均低于50%, 诱导50%个体进入夏滞育所需求的光 暗循环数在L15∶D9, L16∶D8, L17∶ D7和L18∶D6分别为2.61, 3.72, 4.64和5.92 d, 处理间存在显著差异。这些结果提示该虫夏滞育的诱导是基于定量的光周期反应。     

朱砂叶螨滞育诱导的研究

朱砂叶螨滞育诱导反应曲线为长日照型,临界光照长度为9小时45分。15℃条件下诱导,0～1小时30分和11～24小时光照时无滞育发生,光照6小时15分至9小时45分则几乎完全滞育。后若螨期和成螨期具光敏感性,最敏感虫态是成螨期。诱导其他虫态,滞育不发生。     

温度和光周期对管侧沟茧蜂滞育诱导及滞育茧的低温冷藏

【目的】为明确诱导管侧沟茧蜂Microplitis tuberculifer 滞育的主要因子,在田间和室内研究了不同温度和光周期下管侧沟茧蜂的滞育率和滞育茧的最佳冷藏温度。【方法】田间实验分别从8月31日到9月25日每隔5 d在室外罩笼内释放管侧沟茧蜂寄生的粘虫幼虫,待寄生蜂结茧后统计子代蜂的滞育率。室内实验共设5个不同温度（16℃, 18℃, 20℃, 22℃和24℃）和7个不同光周期（6L:18D, 8L:16D, 10L:14D, 12L:12D, 14L:10D, 16L:8D和18L:6D）,分别统计寄生蜂在各个处理条件下的滞育率。【结果】在河北中部地区秋季自然条件下,8月底当日平均气温为24.4℃,日平均光照时间为12 h 51 min 时,少数蛹（5.08%）开始进入滞育;9月25日,当日平均气温为17.2℃,日平均光照时间为11 h 36 min以下时,几乎所有蛹个体进入滞育,滞育率达到99.70%。在室内人工控制条件下,当温度为22℃以上,无论光周期如何变化,管侧沟茧蜂不能进入滞育,所结茧全部为非滞育茧。温度为22℃以下存在光周期反应,在温度16℃, 18℃和20℃,光周期10L:14D时形成滞育茧数量最多,滞育率分别为100%, 89.75% 和 29.58%。可见温度和光周期二者共同影响管侧沟茧蜂的滞育。滞育茧在0℃左右条件下冷藏 240 d 和5℃左右环境条件下冷藏180 d, 成虫的羽化率和寄生能力与发育茧差异不显著(P>0.05);0℃条件下冷藏300 d,滞育茧仍有79%可以正常羽化。【结论】该寄生蜂在秋季进入滞育主要是低温条件和短光照反应相互作用的结果,滞育茧在0℃和5℃温度下至少可以保存240 d。这些结果对管侧沟茧蜂的大规模繁殖和滞育茧的保存具有重要参考价值。     

温度和光周期对绿盲蝽滞育诱导的影响

为了阐明环境因子对绿盲蝽Apolygus lucorum Meyer-Dür卵滞育诱导作用,测定了3个温度和6个光周期组合处理对绿肓蝽的滞育诱导和绿盲蝽光周期感应的敏感虫态,系统调查了绿肓蝽在不同温度和不同光照组合下所产卵的孵化率.结果表明:绿盲蝽的敏感虫态为1龄若虫;在17℃,20℃和23℃3个不同温度下,光照时间小...     

稻螟赤眼蜂诱导滞育条件的优化

应用滞育技术是延长赤眼蜂货架期的可行性措施之一。为实现工厂化生产稻螟赤眼蜂滞育蜂,本研究以在3种光周期(16 L∶8 D、12 L∶12 D和8 L∶16 D)下繁育的稻螟赤眼蜂种群为材料,考察了诱导始期(寄生后发育12 h、24 h、36 h、48 h、60 h和72 h)、诱导温度(10℃和13℃)和诱导历期(14 d、21 d、28 d和35 d)对稻螟赤眼蜂滞育的影响。研究结果表明短光照下繁育的种群更容易进入滞育状态;寄生后发育24 h和12 h为最敏感的诱导始期,随着诱导始期虫龄的增长,滞育效果也随之下降;诱导温度对滞育也有显著影响,其中8 L∶16 D的种群在13℃下诱导的滞育率要显著高于10℃,但其他两个种群在10℃下诱导的滞育率要显著高于13℃;诱导历期的增加可以显著提高稻螟赤眼蜂的滞育率。供试稻螟赤眼蜂种群的较适宜滞育条件为8 L∶16 D下繁育的赤眼蜂种群寄生后发育12 h于13℃下诱导滞育28 d或35 d,以及寄生后发育24 h于10℃或13℃下诱导滞育35 d,滞育率可超过95%。     

Environmental induction of larval diapause and life-history consequences of post-diapause development in the Large Copper butterfly,Lycaena dispar (Lepidoptera: Lycaenidae)

Many insects in temperate zones withstand the adverse conditions of winter through entering diapause and the two most important environmental stimuli that induce diapause are photoperiod and ambient temperature. The Large Copper butterfly, Lycaena dispar Haworth (Lepidoptera: Lycaenidae), is a Palearctic butterfly that hibernates as larvae. Since this butterfly is a near threatened species in some regions, there has been a growing need for a standardized protocol for mass rearing of this butterfly based on the adequate knowledge of its ecology. In the present study, we first identified that L. dispar larvae were sensitive to the photoperiodic induction of diapause during their first larval instar. We then investigated to what extent the diapause-inducing effects of photoperiod could be modified by ambient temperatures in L. dispar larvae by exposing them to the range of day-lengths (L:D 14:10, 12:12, 10:14 and 8:16) at three different temperatures (15, 20 and 25 °C). All larvae were induced to enter diapause at low ambient temperature (15 °C) regardless of photoperiod, whereas most of them (86 %) exhibited direct development when temperature was high (25 °C). The photoperiodic induction of diapause was evident when day-length was shorter than 14 h at intermediate temperature (20 °C). Pre-diapause development was prolonged at low temperatures. Finally, we found that post-diapause development of L. dispar larvae was determined by both the chilling temperature experienced by diapausing larvae and the duration of larval diapause. Adult emergence was enhanced when larvae were chilled at 8 °C and when they had been under the state of diapause for 20 days before they were treated to terminate diapause.     

Induction and termination of diapause inOrius predatory bugs

Photoperiodic induction of reproductive diapause at 18°C was investigated in fourOrius [Heteroptera: Anthocoridae] species.Orius insidiosus (Say) displayed a long-day response with a critical photoperiod between L11:D13 and L12:D12. Diapause in this species was terminated rapidly when the temperature and/or the daylength were increased.Orius majusculus (Reuter) also displayed a long-day response. The critical photoperiod fell between L14:D10 and L16:D8. Diapause in this species was not terminated within 14 days when both temperature and daylength were increased. InOrius albidipennis (Reuter) no diapause could be induced at photoperiods varying from L8:D16 to L16:D8. InOrius tristicolor (White) a high proportion of diapause was found at all photoperiods tested. The effect of temperature on photoperiodic induction of diapause was studied inO. insidiosus at L10:D14. Diapause occurred at 18°C, 21°C and 25°C, but not at 30°C. Again, diapause was terminated rapidly after transfer to 25°C/L16:D8. Exposing only the nymphal instars 1–5 to short daylength was not enough to induce diapause in the whole population ofO. majusculus. Orius predatory bugs are used as biocontrol agents against western flower thrips,Frankliniella occidentalis (Pergande) [Thysanoptera: Thripidael, in greenhouses. The consequences of photoperiodic induction of diapause for the success of early season releases ofOrius are discussed.     

Effects of photoperiod and temperature on diapause induction in Conogethes punctiferalis (Lepidoptera: Pyralidae)

The yellow peach moth, Conogethes punctiferalis (Guenée), a multivoltine species that overwinters as diapausing larvae, is one of the most serious insect pests on maize in China. Effect of photoperiod and temperature on larval diapause was examined under empirical laboratory conditions. Short‐day treatments caused larval diapause at 25°C, and the critical photoperiod was between 12 and 13 h (or 12 h 51 min) light per day. No sensitive instar was identified for diapause induction under alternated short‐ (L : D 11 : 13 h) and long‐day (L : D 14 : 10 h) treatments at different larval stages. However, accumulative treatment of three instars and 10 d under short‐day treatment was required for the induction of 50% larval diapause. All larvae entered diapause at 20°C, whereas less than 3% did so at 30°C, irrespective of the long‐ or short‐day treatment. Furthermore, under the short‐day treatment, more than 90% of larvae went into diapause with temperatures ≤ 25°C, but less than 17% did so at 28°C. In contrast, under the long‐day treatment, less than 19% of larvae went into diapause with temperatures ≥ 23°C. The forward shift (5°C) of critical temperature under the long‐day regime demonstrated the compensatory effect of temperature and photoperiod on diapause induction. In conclusion, C. punctiferalis had a temperature‐dependent type I photoperiodic diapause response; there was no sensitive instar for diapause determination, but the photoperiodic accumulation time countermeasures both of the short‐day cycles and the number of instars exposed, and the photoperiodic diapause response, was a temperature‐compensated phenomenon.     

Photoperiodic responses during larval development and diapause of two geographic ecotypes of the rice stem maggot, Chlorops oryzae

Chlorops oryzae is bivoltine in northern Japan but trivoltine in the southern part of the country. In the bivoltine strain, both the egg and larval stages were found to be sensitive to photoperiod. When the egg stage was exposed to a long-day photoperiod (16L:8D), larval development showed a short-day type response, and mature third-instar larvae entered a summer diapause under a long-day photoperiod (15L:9D). When eggs experienced short days, the first-instar larvae entered a winter diapause under short-day conditions, and the critical photoperiod in the larval stage ranged from about 14L:10D to about 12L:12D as the photoperiod experienced by the eggs increased from 12L:12D to 14L:10D. However, the development of the larvae after overwintering was not influenced by the photoperiod. In the trivoltine strain, larval development was retarded under a 14L:10D photoperiod but not under either shorter or longer photoperiods, when larvae had spent the egg stage under a 16L:8D photoperiod. The critical photoperiod of the larval stage for the induction of a winter diapause in the first instar was about 12L:12D, though it varied to some extent with the photoperiod during the egg stage. Thus, Chlorops oryzae was able to adapt itself to the local climatic conditions by the development of variable and complicated photoperiodic responses.     

Diapause initiation and alterations in the life cycle of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) as induced by photoperiodic conditions

Grapholita molesta (Busck) is one of the major pests of Rosaceae, causing significant damage to buds and fruits. In Southern Brazil, its population density is reduced during Rosaceae dormancy months. The present study evaluated the influence of different photoperiods (L:D) (10:14, 11:13, 12:12, 13:11, 14:10 and 16:8) at 25 ± 1oC and 60 ± 10% RH on diapause induction of G. molesta eggs, larvae, prepupae, and pupae. The effects of the photoperiod on the life cycle of non-diapausing insects and on the second generation were also assessed. Prepupal diapause was observed only when eggs and neonates (≤ 12h-old larvae) were exposed to photophases from 10h to 14h long. Development of non-diapausing individuals and those from the second generation tended to be longer in photophases between 10h and 14h long.     

PHOTOPERIODIC CONTROL OF ADULT DIAPAUSE IN CHRYSOPERLA SINICA (TJEDER) (NEUROPTERA: CHRYSOPIDAE— I. CRITICAL PHOTOPERIOD AND SENSITIVE STAGES OF ADULT DIAPAUSE INDUCTION

Abstract  Photoperiodic sensitivity for diapause induction of the green lacewing, Chrysoperla sinica (Tjeder) was examined at 22°C. The adult diapause of C. sinica was induced by short-day photoperiods, and the critical photoperiod for its induction was between 12.5L-11.5D and 13L-11D.
Adults developed without diapause under long-day conditions, and entered diapause under short-day conditions. The adult stage was the uppermost sensitive stage for adult diapause induction, adults could go into diapause only when the emerging adults were under diapause-inducing short-day photoperiods. The short-day photoperiodic experience by transferring between 15L: 9D and 9L: 15D at preimaginal stages did not result in adult diapause under 15L: 9D photo regime, although some treatments extended the pre-oviposition period in adult stage. The results showed that the 3rd instar larvae and pre-pupae were more sensitive to the photoperiodic change from 15L: 9D to 9L: 15D photo regime than the other preimaginal stages.