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暗期干扰对环带锦斑蛾滞育诱导的影响 总被引:1,自引:0,他引:1
在短日照条件下,环带锦斑蛾Pseudopidorus fasciata以4龄幼虫进入冬季滞育,其滞育诱导的临界暗长为10.5 h。本文系统测试了暗期干扰实验[即在暗期采用单一的光(亦称光脉冲)干扰光周期反应的实验]对环带锦斑蛾幼虫滞育的抑制影响。幼虫孵化后在25℃,短日照L9∶D15(光9 h∶暗15 h),L10∶D14、L11∶D13及L12∶D12暗期的不同时段给予1 h或30 min光脉冲干扰。结果表明: 滞育是否被抑制主要取决于暗期的长度,当光脉冲干扰前的暗长(D1)或光脉冲干扰后的暗长(D2)超过临界暗长(10.5 h)时,100%的幼虫被诱导进入滞育;当D1和D2都短于(或等于)临界暗长时,滞育不同程度被抑制,抑制的效果则取决于所干扰的光周期、光脉冲的长度和光脉冲落入的位点。结果说明该虫滞育诱导的暗期干扰反应是基于临界暗长的时间测量。 相似文献
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重阳木锦斑蛾越冬幼虫的耐寒性变化 总被引:1,自引:0,他引:1
【目的】重阳木锦斑蛾Histia rhodope是为害重阳木Bischofia polycarpa的重要害虫之一。本研究旨在了解重阳木锦斑蛾幼虫的抗寒能力,并为探讨抗寒机理提供理论基础。【方法】在越冬期的不同阶段(2017年11月7日、2017年12月7日、2018年1月5日、2018年2月4日和2018年3月5日)分别采集室外重阳木锦斑蛾越冬幼虫,对其体重、过冷却点、结冰点、含水量、脂肪、总糖和总蛋白质含量进行测定。【结果】重阳木锦斑蛾幼虫的过冷却点在越冬期不同月份有显著差异,与环境温度呈显著正相关(P<0.05),最低值出现在1月份,为-15.26℃,最高值出现在3月份,为-13.30℃;结冰点变化趋势与过冷却点一致;体重和脂肪含量在越冬期间逐渐下降,与过冷却点无相关性(P>0.05);过冷却能力随着虫体游离水含量的升高而降低,随其降低而升高,而结合水含量的变化趋势恰好相反;总糖含量在11月最高,为14.95 μg/mg,显著高于3月份的5.07 μg/mg;总蛋白质含量在越冬期间呈先升高后降低的趋势,在1月份含量最高,为23.66 μg/mg,显著高于11月份的含量(16.69 μg/mg)。【结论】重阳木锦斑蛾幼虫的耐寒性在越冬期间随气温的降低逐渐增强,随气温的回升又逐渐减弱;蛋白质可能是该虫重要的耐寒物质。 相似文献
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为研究云南锦斑蛾Achelura yunnanensis幼虫的化学防御策略, 利用硅胶柱色谱和HPLC制备色谱等色谱学方法对其毒性分泌液进行了化学成分的分离, 并通过核磁共振和质谱学方法对分离到的成分进行了结构鉴定。从其毒性分泌液中分离得到了两个神经毒性氰苷类化合物, 经鉴定分别为linamarin和lotaustralin。取食试验表明, linamarin对黑头酸臭蚁Tapinoma melanocephalum有明显的拒食活性。我们推测, 云南锦斑蛾体内的神经毒性物质氰苷是通过摄取宿主植物冬樱花Prunus cerasoides和云南樱花P. majestic而获得的, 并在体内转化形成毒液, 用于防御其天敌。本研究为云南锦斑蛾和宿主植物的协同进化提供了化学依据。 相似文献
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高温胁迫对白眉野草螟滞育幼虫存活特性的影响 总被引:2,自引:0,他引:2
【目的】白眉野草螟 Agriphila aeneociliella 是小麦上新发现的一种害虫,以滞育的老熟幼虫做土茧在土壤中越夏,研究明确滞育幼虫在夏季持续高温和极端高温条件下的存活率,为该害虫秋季虫源基数的预测预报和有效防控提供依据。【方法】以白眉野草螟带土茧滞育幼虫和不带土茧滞育幼虫为研究对象,在室内条件下设置43,46,49,52和55℃极端高温,分别处理0.5,1,2和4 h;设置35,37,39和41℃普通高温,分别处理1,2,4和8 d。【结果】极端高温处理2和4 h后,带土茧滞育幼虫半致死温度分别为50.04℃(95%置信区间: 49.36~50.47℃)和48.81℃(95%置信区间: 47.74~49.37℃),去除土茧后分别为48.20℃(95%置信区间: 47.66~48.74℃)和47.36℃(95%置信区间: 47.08~48.37℃);52℃温度条件下,带有土茧滞育幼虫半致死时间为1.29 h(95%置信区间: 1.17~1.44 h),去除土茧后半致死时间为1.02 h(95%置信区间: 0.93~1.18 h)。普通高温处理41℃时,带有土茧滞育幼虫半致死时间为3.21 d(95%置信区间: 2.92~3.52 d),去除土茧后半致死时间为2.66 d(95%置信区间: 2.33~3.02 d)。【结论】白眉野草螟滞育幼虫具有很强的耐高温能力,土茧对其具有一定的保护作用。小麦收割后深耕灭茬,使土茧或幼虫裸露到地表,利用夏季土表高温杀死滞育幼虫,可以作为一项有效的农业防治措施。 相似文献
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在室内测定了二化螟滞育幼虫与非滞育幼虫对杀虫单和三唑磷的抗药性。测试结果表明,二化螟滞育幼虫比非滞育幼虫具有更高的抗药性。杀虫单对二化螟滞育幼虫与非滞育幼虫的LD50分别为24.3452μg/头与10.4721μg/头;三唑磷的LD50分别为0.0685μg/头和0.0497μg/头. 相似文献
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在以卵滞育的昆虫中昆虫滞育时的生理代谢特点已经得到了大量研究。本文对以末龄幼虫(5龄)滞育的大斑芫菁Mylabris phalerate(Pallas)在不同滞育阶段体内糖类和醇类代谢的特征进行了研究。结果表明: 滞育个体血淋巴中的海藻糖含量高于非滞育个体,且随滞育时间的加大逐渐升高,滞育5个月时达到最大值,为5.61 μmol/mL。糖原的含量随滞育的进程逐渐减少,滞育初期(0.5个月)为0.72 mg/mL,到滞育末期(5个月)时仅为0.1 mg/mL。滞育个体脂肪体中的海藻糖含量都高于非滞育个体,滞育1个月时为非滞育个体的3倍,至滞育末期时达非滞育个体的5倍,为2.5 μmol/g脂肪体。糖原含量总体变化趋势是随滞育时间的加大逐渐减少,滞育早期和中期都高于非滞育个体。在滞育过程中血淋巴积累的小分子多元醇主要为甘油,其次是山梨醇;而在脂肪体中主要为甘油,其次是甘露醇,少量积累山梨醇:表明大斑芫菁滞育幼虫主要积累的是海藻糖和一些小分子多元醇。滞育幼虫在准备滞育时储备了大量糖原,这些糖原可能为滞育期间海藻糖、山梨醇和甘油的代谢提供了原料。 相似文献
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【目的】本研究旨在明确云南锦斑蛾Achelura yunnanensis雌雄成虫触角、喙管和跗节等主要化感器官上的感器种类和差异,为后续该虫化学感受相关的研究奠定基础。【方法】采用光学显微镜和扫描电镜,观察了云南锦斑蛾雌雄成虫触角、喙管和跗节的形态特征及其感器的类型和超微结构。【结果】云南锦斑蛾雌雄成虫触角上有7类17种感器,包括5种锥形感器(sensilla basiconica, SB)、3种毛形感器(sensilla trichodea, ST)、3种刺形感器(sensilla chaetica, SCH)、2种Bhm氏鬃毛(Bhmbristles, BB)、2种腔锥形感器(sensilla coeloconica, SCO)、1种耳形感器(sensilla auricillica,SAU)和1种鳞形感器(sensilla squamiformia, SSQ),其中Bhm氏鬃毛I型仅分布在雄虫触角上,毛形感器II型和III型以及腔锥形感器I型在长度上具有性二型现象。雌雄成虫喙管上有2类5种感器,包括4种锥形感器和1种刺形感器,其中锥形感器III型仅在雌虫喙管上有分布。此外,雌雄成虫跗节上有5类13种感器,包括4种毛形感器、4种锥形感器、2种鳞形感器、2种Bhm氏鬃毛和1种刺形感器,其中毛形感器I型仅分布在雌虫跗节上,锥形感器I型和III型仅在雄虫跗节上有分布,锥形感器IV型和Bhm氏鬃毛I型在长度上具有性二型现象。【结论】云南锦斑蛾雌雄虫触角上有17种感器,喙管上有5种感器,跗节上有13种感器,部分感器在种类、长度或数量上具有性二型现象。 相似文献
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The effect of daylength and temperature on the regulation of the larval diapause of a central Missouri population of the sunflower moth, Homoeosoma electellum, was examined. Fully grown fourth-instar larvae exhibit a facultative diapause. Measurements of the effect of photoperiod on diapause induction revealed critical photoperiods of about 13 h 30 min light/day at 20°C, and between 11 h 45 min and 12 h light/day at 23°C. Third and fourth-instar larvae were shown to be the main sensitive stages for diapause determination. Daylength was also shown to be an important regulator of the rate of diapause development. A short day of LD 10:14 h permitted only a low rate of diapause development, whereas long days of LD 14:10 h and LD 16:8 h accelerated diapause development at 25 and 30°C. When long days were alternated with short days at 30°C the accelerating effect of long days on diapause development was not found. Systematic transfers of chilled diapausing larvae revealed an accelerated diapause development in groups transferred from 10 to 30°C LD 10:14 h, but diapause development was not accelerated in groups transferred from 10 to 30°C LD 16:8 h. 相似文献
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Abstract: The pine sawyer Monochamus galloprovincialis is the vector of the introduced pine wood nematode Bursaphelenchus xylophilus in Portugal and has a fixed univoltine life cycle, overwintering as larvae inside the wood. We investigated the possibility of the existence of a phase of winter dormancy affecting the larvae, its induction and termination under controlled conditions and its incidence and termination in the field. In the laboratory, the majority of the newly hatched larvae which were maintained at a constant temperature of 23°C and different photoperiods became dormant in <70 days. Part of the population completed dormancy and reassumed development until adult emergence at the constant temperature, without the need for a chilling period. Although no critical photoperiod for dormancy maintenance or termination could be determined, dormancy termination was more frequent for larvae experiencing changes on daylength duration. In the field, dormancy incidence grew progressively from a minimum of 26% in October to a maximum of 100% in April, and dormancy appeared to be completed only during late winter. The results suggest that M. galloprovincialis larvae underwent an obligatory dormancy associated with the last larval instar, which conforms to the general definition of diapause, although presenting some affinities with oligopause. The role of this dormancy on the regulation of the pine sawyer's seasonal development and the number of generations is discussed. 相似文献
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A wild bean weevil,Kytorhinus sharpianus Bridwell (Coleoptera: Bruchidae), has a multivoltine life cycle and enters a hibernal larval diapause at the fourth instar
under a short daylength (Shimada & Ishihara, 1991). Here, we investigated their diapause incidence under different photoperiods
at 24°C and 27°C. The critical photoperiods for diapause induction were 14.5 h at 24°C and 14 h at 27°C. The stages susceptible
to diapause-inducing stimuli were estimated by transferring larvae of various instars from long days to short days and vice
versa. Then we investigated the incidence of larval diapause. The sensitive stage was estimated to be from the third to early
fourth instar. Though larval diapause, which was induced under a short daylength, was terminated only by increasing the daylength,
the termination was more synchronized by an exposure to a low temperature followed by increasing temperature, irrespective
of photoperiod. 相似文献
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JianJun Tang XingPing Liu HaiMin He LiLi Huang ShaoHui Wu FangSen Xue 《Ecology and evolution》2022,12(5)
The life cycle of the cabbage beetle Colaphellus bowringi in southeastern China is complex due to four options for adult development: summer diapause, winter diapause, prolonged diapsuse, and nondiapause. However, detailed information on the multi‐year emergence patterns of diapausing individuals in this beetle has not been documented. In this study, we monitored the adult emergence patterns of diapausing individuals and estimated the influence of the diapause‐inducing temperature and photoperiod on the incidence of prolonged diapause under seminatural conditions for several years. The duration of diapause for adults collected from the vegetable fields in different years varied from several months to 5 years. Approximately 25.9%–29.2% of individuals showed prolonged diapause (emergence more than 1 year after entering diapause) over the 5 years of observation. Furthermore, regardless of insect age, the emergence of diapausing adults from the soil always occurred between mid‐February and March in spring and between late August and mid‐October in autumn, when the host plants were available. The influence of diapause‐inducing temperatures (22, 25, and 28°C) combined with different photoperiods (L:D 12:12 h and L:D 14:10 h) on diapause duration was tested under seminatural conditions. Pairwise comparisons of diapause duration performed by the log‐rank test revealed that the low temperature of 22°C combined with the long photoperiod of L:D 14:10 h induced the longest diapause duration, whereas the low temperature of 22°C combined with the short photoperiod of L:D 12:12 h induced the highest proportion of prolonged diapause. This study indicates that C. bowringi adopts a multi‐year dormancy strategy to survive local environmental conditions and unpredictable risks. 相似文献
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Eggs of the European skipper, Thymelicus lineola, containing pharate first-instar larvae were brought into the laboratory at the beginning of each month from September to May and maintained at 20°C, 14L:10D. No emergence was observed within 40 days of collection before December. From that time on, while total emergence was similar, the duration of the emergence period decreased over the season from > 120 days in December to < 14 days in May. There was however no marked change in the seasonal supercooling point values of diapausing larvae.The rate of emergence from eggs collected in March was influenced by photoperiod, being slower under short-day conditions. However for any given photoperiod tested, the rate of emergence increased with an increase in temperature. The possible adaptive significance of a two-phase diapause, where diapause termination is photoperiodically controlled in species that overwinter as an egg or as a pharate first-instar larva within the egg chorion in exposed habitats, is discussed. 相似文献
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Abstract To investigate the seasonal adaptation strategies of Ophraella communa to new habitats, the effects and regulation mechanisms of photoperiod and temperature on the reproductive diapause in a population collected from Changsha, Hunan were examined. Adults showed obvious reproductive diapause, which was regulated by photoperiod and temperature. At 30°C, there was no adult diapause occurring under either long‐day or short‐day conditions; at 25°C the pre‐oviposition period was short and fecundity was high in adult females under L : D 16 : 8 h, whereas under L : D 12 : 12 h, a few females entered reproductive diapause; at 20°C under short‐day conditions, all female adults entered diapause. The pre‐oviposition period was significantly prolonged when the pupae and adults were transferred from long‐days to short‐days, but the day length influence was not obvious when they were transferred only in the adult stage. However, the fecundity dropped greatly no matter whether the photoperiod shifted to short‐days only in the adult stage or whether the shift occurred in both the pupal and adult stage. The fecundity was extremely low when photoperiod shifted from long‐days to short‐days in both pupal and adult stages. This was an indication that the pupal and adult stages were the photoperiod‐sensitive stage for adult reproductive diapause. This was especially true for the photoperiod in the pupal stage, which has a distinctly significant regulative effect on reproductive diapause. Additionally, this article also addresses the reason for different photoperiodic response patterns in reproductive diapause induction between the Changsha strain and the Tsukuba strain (Japan) of O. communa. 相似文献
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KAZUHIRO TANAKA 《Physiological Entomology》1991,16(2):249-262
Abstract In order to elucidate the mechanism regulating its seasonal life cycle, the photoperiodic response of Achaearanea tepidariorum has been analysed. Nymphal development was faster in long-day and slower in short-day photoperiods. The combined action of low temperature, poor food supply and short daylength induced diapause at an earlier developmental stage than short days alone. Thus, photoperiod is a primary factor inducing nymphal diapause, but the diapausing instar is influenced by both temperature and food supply. Hibernating nymphs became unresponsive to photoperiod in late December. After hibernation, however, sensitivity was restored and the nymphs remained sensitive to photoperiod throughout their life. This spider could also enter an imaginal or reproductive diapause. Photoperiod was again a primary inducing factor and temperature modified the photoperiodic response to some extent. The induction of the reproductive diapause was almost temperature-compensated whereas development was not. So the involvement of a photoperiodic counter system was suggested. Irrespective of whether the nymph had experienced diapause or not, the imaginal diapause was induced in response to a short-day photoperiod after adult moult. Based on these observations, the seasonal life cycle and the adaptive significance of nymphal and imaginal diapause are discussed. 相似文献