光周期对飞蝗三个地理种群胚胎滞育和生殖的影响(英文)

本文研究了光周期对飞蝗三个地理种群胚胎滞育和生殖的影响。结果表明飞蝗不同地理种群胚胎滞有特性存在显著差异。新疆和硕飞蝗种群无论在长光照还是短光照下均产滞育卵,属于专性滞育;天津北大港和新疆哈密飞蝗种群的胚胎滞育随光周期的不同而变化,长光照和短光照下分别产非滞有卵和滞育卵,属于不同类型的兼性滞育。在纬度等条件差别不大的情况下,海拔高度对滞有特性的影响可能起主导作用。长光照延长哈密和北大港飞蝗种群的产卵前期、降低其产卵频率及产卵量;但对和硕飞蝗种群的这些特性无明显影响。和硕飞蝗种群胚胎打破滞育所需的低温处理时间较哈密和北大港飞蝗种群所需时间长。     

Geographic variation in diapause induction and termination of the cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

Overwintering diapause in Helicoverpa armigera, a multivoltine species, is controlled by response to photoperiod and temperature. Photoperiodic responses from 5 different geographical populations showed that the variation in critical photoperiod for diapause induction was positively related to the latitudinal origin of the populations at 20, 22 and 25 °C. Diapause response to photoperiod and temperature was quite different between northern and southern populations, being highly sensitive to photoperiod in northern populations and temperature dependence in southern populations. Diapause pupae from southern population showed a significantly shorter diapause duration than from northern-most populations when they were cultured at 20, 22, 25, 28 and 31 °C; by contrast, overwintering pupae from southern populations emerged significantly later than from northern populations when they were maintained in natural conditions, showing a clinal latitudinal variation in diapause termination. Diapause-inducing temperature had a significant effect on diapause duration, but with a significant difference between southern and northern populations. The higher rearing temperature of 22 °C evoked a more intense diapause than did 20 °C in northern populations; but a less intense diapause in southern population. Cold exposure (chilling) is not necessary to break the pupal diapause. The higher the temperature, the quicker the diapause terminated. Response of diapause termination to chilling showed that northern populations were more sensitive to chilling than southern population.     

Sex‐linked inheritance of diapause induction in the butterfly Pieris napi

Many temperate insects survive harsh environmental conditions, such as winter, by entering a state of developmental arrest. This diapause state is predominantly induced by photoperiod. The photoperiod varies with latitude and has led to local adaptation in the photoperiodic induction of diapause in many insects. To understand the rapid evolution of the photoperiodic threshold, it is important to investigate and understand the underlying genetic mechanisms. In the present study, the genetic basis of photoperiodic diapause induction is investigated in the green‐veined white butterfly Pieris napi (Lepidoptera, Pieridae) by assaying diapause induction in a range of conditions for a Swedish and Spanish population. Furthermore, the inheritance of diapause induction is assessed in reciprocal F1 hybrids and backcrosses between the two populations. The southern population shows a clear photoperiodic threshold determining diapause or direct development, whereas the northern populations show a high incidence of diapause, regardless of photoperiod. The hybrid crosses reveal that the inheritance of diapause induction is strongly sex‐linked, and that diapause incidence in the genetic crosses is highly dependent on photoperiod. This emphasizes the importance of assaying a range of conditions in diapause inheritance studies. The results indicate a strongly heritable diapause induction with a major component on the Z‐chromosome, as well as a minor effect of the autosomal background.     

中华稻蝗五地理种群的卵滞育强度及生活史模式变异

为调查中华稻蝗Oxya chinensis的地理适应,自北纬42.3°至20.0°采集了5个地理种群的标本,比较了其子代的卵滞育发生、滞育强度及成虫虫体大小。结果表明: 不同的中华稻蝗地理种群显示了不同的光周期和温度反应模式。铁岭、济宁和泗洪种群的滞育不受光周期和温度的影响,滞育率均为100%。南方的长沙和海口种群仅部分卵进入滞育,海口种群在短日条件下的滞育率高于长日条件,卵期温度亦对其滞育有较大的影响,而长沙种群的卵滞育仅受卵期温度的调控。长沙和海口种群的卵滞育强度最弱,其次是铁岭种群,中间纬度的济宁和泗洪种群的滞育强度最高。在北方的一化性种群中,滞育强度随着纬度的降低而增强。成虫的虫体大小因栖息地纬度的变化而呈现复杂的变异,北方种群的虫体大小与栖息地纬度存在显著的负相关关系,而长沙和海口种群的虫体小于济宁和泗洪种群。结果提示中华稻蝗各种群已形成各自的地理适应机制,纬度梯度在其生活史的形成和发育中起着重要的作用。     

光温条件明显影响棉铃虫的滞育强度

为了探明不同地理种群棉铃虫Helicoverpa armigera滞育强度的地理变异, 本研究系统地比较了光温条件（光照时数 11～16 h, 恒温20, 22, 25, 28和31℃及变温）对来自中国的4个地理种群（广东广州、 江西永修、 山东泰安和辽宁喀佐）棉铃虫滞育强度的影响。结果表明： 滞育诱导的光周期对继后棉铃虫的滞育强度有明显影响。在光照时数11～14 h范围内, 各地理种群的滞育持续期均随着光照时数的增加而延长。滞育强度也受到滞育诱导的温周期影响, 当光期温度相同时, 低纬度的GZ种群温周期比恒温有更强的诱导效应; 中纬度的YX种群温周期与恒温具有相同的滞育诱导强度; 高纬度的KZ和TA种群温周期所诱导的滞育强度一般低于恒温。滞育解除过程中的温度也显著影响到滞育的解除, 在20~31℃下, 温度愈高滞育解除愈快; 滞育持续期同时受到滞育诱导温度的影响, 对于北方的泰安种群和喀佐种群, 较高的滞育诱导温度能诱导更强的滞育。     

Effects of photoperiod and temperature on diapause induction and termination in the swallowtail,Sericinus montelus

Abstract Sericinus montelus overwinters as diapausing pupae. In the present study, the effects of photoperiod and temperature on diapause induction and termination of diapause are investigated. The results obtained demonstrate that high temperature can reverse the effect of short day‐lengths on diapause induction. Under an LD 12 : 12 h photoperiod, all pupae enter diapause at 15, 20 and 25 °C, whereas all pupae develop without diapause at 35 °C. No pupae enter diapause under an LD 14 : 10 h photoperiod when the temperature is above 20 °C. Photoperiodic response curves obtained at 25 and 30 °C indicate that S. montelus is a long‐day species and the critical day‐length is approximately 13 h at 25 °C. At 25 °C, the duration of diapause is shortest when the diapausing pupae are maintained under an LD 16 : 8 h photoperiod and increases under LD 14 : 10 h and LD 12 : 12 h photoperiods. Under an LD 16 : 8 h photoperiod, the duration of diapause is shortest when the diapausing pupae are maintained at 25 °C, followed by 20 and 30 °C, and then at 15 °C. These results suggest that a moderate temperature favours diapause development under a diapause‐averting photoperiod in this species. The duration of diapause induced by an LD 12 : 12 h photoperiod is significantly longer at 25 °C than those at 15, 20 and 30 °C, and is shortest at 15 °C. At 25 °C, the duration of diapause induced by LD 6 : 18, LD 12 : 12 and LD 13 : 11 h photoperiods is similar and longer than 90 days. Thus, the diapause‐inducing conditions may affect diapause intensity and a photoperiod close to the critical day‐length has significant influence on diapause intensity in S. montelus.     

Effect of variation in photoperiodic response on diapause induction and developmental time in the willow leaf beetle, Plagiodera versicolora

The willow leaf beetle, Plagiodera versicolora (Coleoptera: Chrysomelidae) overwinters in adult diapause. In this study, the photoperiodic responses for diapause induction and developmental time were examined in the Ishikari (Hokkaido, Japan) population of P. versicolora. All females entered reproductive diapause under short daylength (L10:D14), but 31.7% of females did not enter diapause under long daylength (L16:D8). The developmental time from oviposition to adult emergence was significantly longer at L10:D14 than that at L16:D8. Norm of reaction curves illustrated variation among families in the photoperiodic responses for diapause induction and for developmental time. ANOVA indicated significant family × photoperiod interactions in the developmental time. At L16:D8, developmental time was positively correlated with the incidence of diapause in females. This means that a female having a longer developmental time tends to have a longer critical photoperiod. Such variation may be maintained by differences in selection pressures on the growth rate and the critical photoperiod for diapause induction between univoltine and bivoltine genotypes because Ishikari is located in a transitional area between populations with univoltine and bivoltine life cycles.     

Geographical variability in ecophysiological traits controlling dormancy in Chrysopa oculata (Neuroptera: Chrysopidae)

Dormancy in Chrysopa oculata, a multivoltine species, is controlled by reponses to photoperiod and temperature. Variation in both the critical photoperiod for diapause induction and the duration of diapause is positively related to the latitudianl origin of the population. The incidence of photoperiodically induced diapause also varies geographically; at 24°C the southern-most population is more variable for diapause induction than the northern populations. By contrast, there is little interpopulation variation in thermally determined rates of post-diapause development. The results suggest that the lower threshold for development and the thermal requirements above the threshold may be functionally correlated.     

Effects of photoperiod and temperature on reproductive diapause in Ophraella communa (Coleoptera: Chrysomelidae), a potential biocontrol agent against Ambrosia artemisiifolia

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.     

Very long diapause and extreme resistance to population disturbance in a galling insect

1. Some insects have a prolonged diapause – a dormancy that extends over more than 1 year. In most species prolonged diapause involves one or a few extra years, but in extreme cases diapause may surpass 10 years. Few cases of very long diapause have been described, and very little is known about the population consequences of the temporal refuge formed by the diapausing individuals. 2. The gall midge Contarinia vincetoxici Kieffer galls the flowers of a long‐lived herb Vincetoxicum hirundinaria Med. After completing development, larvae leave the galls for the ground where they enter diapause. Extending an earlier published inoculation experiment, we show that the diapause may last up to at least 13 years, with a median duration of at least 6 years. 3. The gall midge is attacked by two parasitoid species. Dissections of gall midge larvae for presence of parasitoids revealed that Omphale salicis Haliday had a maximum 2 year diapause and Synopeas acuminatus Kieffer a maximum 4 years. The very long diapause of the gall midge may thus provide a temporal refuge from these enemies. 4. In a 15‐year field experiment all galls were removed every year from six isolated habitat patches. Density changes in experimental populations were not statistically different from control populations for over a decade. After 14–15 years a modest decline could be observed. This slow response illustrates that prolonged diapause in C. vincetoxici provides a very strong population buffer against mortality during the galling stage.     

Life‐history traits related to diapause in univoltine and bivoltine populations of Ypthima multistriata (Lepidoptera: Satyridae) inhabiting similar latitudes

In most temperate insects, diapause strategies and voltinism generally exhibit latitudinal clines, supporting the concept that they represent adaptations to climate. In contrast, in the satyrine butterfly Ypthima multistriata Butler, local populations with different voltinism patterns are geographically intermingled, suggesting that life‐history traits related to diapause may differ even between geographically and phylogenetically close populations. In this study, we experimentally examined the critical photoperiod for diapause induction and the larval developmental period in two univoltine and two bivoltine populations of Y. multistriata, all of which inhabit virtually the same latitude (34.652–34.750°N). We found that the critical photoperiod for diapause induction was longer in the univoltine populations than in the bivoltine populations. Moreover, the larval period under the long day length treatment was different among populations in both sexes, although significant differences were also detected between populations with the same voltinism. These results indicate that in Y. multistriata, life‐history traits related to diapause can not be attributed merely to climatic conditions such as temperature or day length, which depend largely on latitude. Therefore, we suggest that biotic elements, such as leaf toughness, as well as abiotic elements should be taken into account in attempts to explain the enigmatic pattern of geographic variation in the diapause strategies of Y. multistriata.     

Geographical variation of photoperiodic wing form determination and genetic background of reproductive diapause in arrhenotokous populations of <Emphasis Type="Italic">Thrips nigropilosus</Emphasis> Uzel (Thysanoptera: Thripidae) in Japan

To determine the level of inter-population variation in wing form and the induction of reproductive diapause as affected by photoperiod, females of five populations of arrhenotokous Thrips nigropilosus Uzel were reared under four different photoperiodic conditions at 18°C. The experimental populations originated from Nakijin-son, Motobu-cho, and Uruma-shi in Okinawa Island, Amami-shi in Amami-Oshima Island, and Wakayama-shi on Honshu Island. In all five populations, only macropterae were observed when the photoperiod was 13 h light/11 h dark. Brachypterae were observed as the light period was reduced to 11.5 or 12 h in the Wakayama population, and to 10 or 11.5 h in the Nakijin, Motobu, and Uruma populations. Brachypterous females were observed in the Amami population only when the light period was 10 h. With the same photoperiod, only brachypterae were observed in the Wakayama and Uruma populations. Short-day conditions also induced reproductive diapause in the Wakayama population but not in the Amami and Okinawa Island populations. Under 10 h light/14 h dark, almost all hybrids obtained from crossing Wakayama with Amami populations entered reproductive diapause. Some populations in Okinawa Island may have been originated in northern localities.     

光周期和温度对亚洲玉米螟滞育诱导的影响

亚洲玉米螟Ostrinia furnacalis (Guenée)属兼性滞育昆虫, 其滞育特性与种群利用适生境的最大化和季节性活动密切相关。解析季节性因素如光周期和温度对其滞育的诱导作用可为预测种群发生动态提供科学依据。本实验在HPS 500型和HPG-320H型自动控制环境气候箱中, 测定了RH 80%下温度20℃, 27℃和30℃与11个光周期组合对吉林农安（NA）、 河北衡水（HS）、 广东惠州（HZ）和海南海口（HK）等4个地理种群的滞育诱导作用。结果表明： 光周期、 温度及其交互作用均对亚洲玉米螟滞育诱导具有重要影响, 其中光周期在滞育诱导中起主导作用。在20℃条件下, 其光周期反应曲线属典型的长日照反应型, 临界光周期随种群分布的地理纬度降低而缩短, 4个地理种群NA, HS, HZ和HK的临界日昼长依次为14 h 3 min, 13 h 59 min, 13 h 32 min和13 h 7 min, 最有效的滞育诱导光周期是日昼长12 h。另一方面, 随种群分布纬度升高, 其对光周期诱导滞育的敏感性降低。温度为27℃时, 其光周期反应曲线为短日照 长日照反应型, 各种群有两个临界光周期, 临界日昼长依次为12 h 50 min和13 h 32 min, 11 h 35 min和13 h 8 min, 12 h 58 min和13 h 1 min, 以及11 h 50 min和12 h 26 min, 且最有效的滞育诱导光周期范围的滞育率明显低于20℃。一定温度范围内（20℃～27℃）, 随温度升高, 临界光周期缩短; 温度达到30℃时则滞育显著被抑制, 滞育率仅为4.3%或更低。这些结果说明温度对亚洲玉米螟滞育的光周期诱导具有很强的补偿作用。因此, 在自然界亚洲玉米螟的滞育属具有温度补偿作用的长日照反应型昆虫, 临界光周期随地理纬度北移而增长; 种群滞育的短日照 长日照反应型特性可能是产生局部世代种群的重要内因。     

Photoperiod-dependent adult diapause within a geographical cline in the multivoltine bruchid Bruchidius dorsalis

Abstract The bruchid beetle Bruchidius dorsalis Fahraeus (Coleoptera: Bruchidae) has been known to undergo larval diapause during the final instar under short photoperiods ( Kurota & Shimada, 2001 ). This species has a multivoltine life cycle and the overwintering stages show a geographical variation across Japan ( Kurota & Shimada, 2002 ). In cooler areas, overwintering occurs during the final instar, whereas in warmer climates overwintering can occur during several developmental stages: non‐diapausing young instars, diapausing instars, and adults. In this study, we investigated the adult reproductive diapause in three populations from different geographical regions to clarify the role of geographical variation on overwintering strategies. We found that: (1) B. dorsalis entered reproductive diapause in addition to larval diapause under short photoperiods, (2) diapause propensity was higher and the critical photoperiod was longer in populations from cooler regions, and (3) the sensitive photoperiod range was the first 5 days after emergence. Predictions of the overwintering stage, derived from critical photoperiods, were consistent with actual overwintering stages observed in each population. The geographical variation in diapause induction is likely to reflect the adaptive overwintering strategy in each local environment.     

Geographic variation in diapause induction under constant and changing conditions in Helicoverpa armigera

Variation in the incidence of diapause in local populations of Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae) was examined in relation to changes in photoperiod and/or temperature during the larval period. Temperate zone populations of H. assulta, a native species in temperate Japan, showed a high incidence of diapause induction when only the photoperiod was decreased during the larval period, even at favorable temperatures. This photoperiod‐dependent response may allow H. assulta to foresee the beginning of autumn well in advance in the temperate zone, where temperature conditions are severe. In contrast, temperate zone populations of H. armigera, an invasive and polyphagous species mainly distributed in the subtropics, showed a high incidence of diapause only when both photoperiod and temperature decreased, whereas subtropical populations showed a very low incidence of diapause under the same conditions. Furthermore, both temperate zone and subtropical populations of H. armigera enter diapause under constant low temperatures at short‐day photoperiod. Thus, there is geographic variation in sensitivity to diapause‐inducing stimuli (changes in photoperiod and temperature) in H. armigera. This variation may be a part of the climatic adaptation achieved by H. armigera in Japan.     

Geographic variation in photoperiodic diapause induction and diapause intensity in Sericinus montelus (Lepidoptera: Papilionidae)

Abstract Due to the risk of extinction and ornamental value of the swallowtail butterfly, Sericinus montelus Gray (Lepidoptera: Papilionidae) in China, knowledge about local adaptations is important for the conservation and economical utilization of the species. In the present study, photoperiodic diapause induction and diapause intensity of S. montelus populations from Jiamusi (46°37′N), Beijing (40°15′N), Zibo (36°48′N), Fangxian (32°36′N), Wuhan (30°33′N) and Huaihua (27°33′N) were characterized at 25°C. Logistic regression analysis revealed a significant population × hours of light interaction, confirming that photoperiodic responses varied among populations. The critical photoperiod was positively correlated with latitude and increased toward the north at a rate of about 1 h for each 6.67 degrees of latitude. Survival analyses indicated that survival time of diapausing pupae before adult eclosion differed significantly among populations at 25°C and 16 : 8 L : D h. The mean duration of pupal diapause was also positively correlated with latitude. Our study reveals geographic variation in the critical photoperiod for diapause induction and in diapause intensity of S. montelus. These results provide useful information for our general understanding about seasonal adaptation in insects and may also be used to predict how geographic populations respond to climate warming.     

Geographic variation in diapause response of adult Rhipicephalus appendiculatus ticks

Diapause in adults of the African brown ear tick Rhipicephalus appendiculatus is dependent on latitude and stock origin. Lower latitude populations, that is, those nearer the equator, show no diapause response to long or short day exposure. Diapause response to short day lengths is found in higher latitude populations, further south, and increases with increasing latitude. Nearly all individuals in the southernmost population, used in this study, enter diapause under short and long day exposure which implies that the onset of diapause in this population is obligatory. Diapause termination in higher latitude populations is induced by increasing photo period, further north, but still south of the equator, diapause is terminated by ageing. The differences in diapausing behaviour of the different populations are discussed in relation to their climatic conditions. This revised version was published online in July 2006 with corrections to the Cover Date.     

Geographical variation in dormancy in a copepod: evidence from population crosses

Populations of the freshwater copepod Mesocyclops edax inhabiting Michigan lakes are dormant during winter, whereas populations inhabiting Florida lakes develop and reproduce continuously throughout the year. A Michigan and a Florida population were exposed to dormancy inducing conditions (low temperature and short photoperiod) in the laboratory and observed for indications of dormancy. All Michigan individuals and a small percentage of the Florida individuals entered dormancy as indicated by prolonged duration of the fourth copepodid instar and cessation of feeding. I suggest that in these population these observations represent diapause, rather than quiescence. The two populations were crossbred to examine the nature of inheritance of dormancy. The F₁ hybrids exhibited an incidence of diapause approximately intermediate between the Florida and Michigan parental stocks. The backcrosses of F₁ individuals to the Michigan and Florida stocks, respectively, exhibited a high and an intermediate incidence of diapause. Survival of the F₂ crosses was very low. The present study presents evidence of genetic differentiation between the Michigan and Florida populations of M. edax with respect to ability to diapause.     

Diapause and biological cycle of Cydalima perspectalis (Walker) in the eastern Pyrenees

Boxwood is a very important component of the natural forests of the eastern Pyrenees. In the low altitudes of these forests, the invasive species Cydalima perspectalis (Walker) causes considerable damage, and there is concern that it will migrate towards the natural forests at higher altitudes. To determine the biological parameters of the local pest population, a semiartificial diet with lyophilized powdered Buxus sempervirens L. leaves was developed. The results obtained indicate that the studied population of C. perspectalis is very similar to the native Japanese population in terms of the number of larval instars to complete development, the development rate and the critical photoperiod for the induction of diapause. It has also been demonstrated that long photoperiods can shorten the duration of larval development. The diapause induction response was classified as type I, and diapause termination was classified as type III. At the two studied temperatures, 25º and 15ºC, the larvae seemed to require a similar number of days in diapause, approximately 3 months, to spontaneously resume development; temperatures can also prompt larvae to resume development. The critical photoperiod in the study area occurs during the second half of August, varying somewhat according to temperature. The greatest defoliation is caused by the offspring of the first generation, while the majority of the larval offspring of the second generation will enter diapause. The survival of natural boxwood in this area will depend on its ability to regrow one or two years after extensive defoliation and on the adaptation of several indigenous natural enemies in the region to feed on C. perspectalis.     

Variability of photosensitive period and voltinism among populations of a butterfly,Ypthima multistriata,inhabiting similar latitudes and altitudes

In Ypthima multistriata Butler (Lepidoptera: Nymphalidae), there are univoltine and bivoltine populations in adjacent areas with similar climatic conditions. A previous study revealed that larvae of both univoltine and bivoltine populations diapause under a constant short day (i.e., a constant short light period; L13:D11), but not under a constant long‐day condition (L16:D8). However, in both types of populations, adults of an overwintering generation appear and oviposit in June and soon thereafter larvae hatch. Therefore, the younger larvae (at least the first instars) of both types of populations experience a long day; nevertheless, the larvae of univoltine populations diapause in nature. To resolve this inconsistency, we set up two hypotheses: (1) the photosensitive stage of larvae is the second instar or later, and (2) the photosensitive stage of univoltine populations is later than that of bivoltine populations. To test these hypotheses, we performed rearing experiments with two univoltine populations and two bivoltine ones. The results indicated that the photosensitive stage was the second or third instar and that the photosensitive stage was later in one univoltine population than in the two bivoltine populations. Larvae of the other univoltine population diapaused under all conditions. The former result supports our hypothesis, and the latter result indicates that the response to photoperiod is different among univoltine populations. In addition, larval development was slower in one univoltine population than in the bivoltine populations, which also delays the timing of the diapause decision in this univoltine population. Larvae that experienced a long day during the first and middle instars but experienced a short day at the end of their larval stage developed faster than larvae that experienced a constant long day. This may be an adaptation to enable emergence before the start of a cold season that is unsuitable for reproduction.