Field and laboratory studies on the effects of temperature on the development of the carrot fly (Psila rosae F.)

The thermal requirements for the pre-oviposition period, egg, larval, pupal and adult stages of the carrot fly were measured under field conditions and at a range of constant temperatures in the laboratory. In the laboratory, the pre-oviposition period lasted from 4 days at 24^oC to 28 days at 9^oC. In general, female carrot flies laid about 20–40 eggs in each batch. Once the first eggs had been laid, subsequent batches were laid after an average of 3 days at 24^oC to 7 days at 11.5^oC. The numbers of days required for egg, larval and pupal development ranged from 5, 31 and 24 days respectively at 21.5^oC to 25, 145 and 84 days respectively at 9^oC. Under laboratory conditions, complete development from egg to adult required from 60 days at 21.5^oC to 254 days at 9^oC. Newly-formed carrot fly pupae were exposed to temperatures of 22–30^oC for various 5–10 day periods during pupal development. Exposure to temperatures of 24^oC and 26^oC caused some, and exposure to 28^oC and 30^oC caused all, of the pupae to delay development. Pupae were sensitive to high temperatures only for approximately 4–10 days after pupation. Under field conditions between mid-May and early September, full carrot fly development (egg-adult) took 84–100 days. The numbers of day-degrees required (base temperatures of 2^oC and 4^oC) for carrot fly development in the laboratory and in the field were similar for egg hatching but not for the pre-oviposition period or for egg-adult development. The thermal requirement for fly development in the field varied between inoculation dates, fewest day-degrees being required when development was rapid.     

Molecular diversity of populations of the Merodon ruficornis group (Diptera, Syrphidae) on the Balkan Peninsula

Genetic diversity of 11 populations of the Merodon ruficornis group (Diptera, Syrphidae) on the Balkan Peninsula was quantified using allozyme electrophoresis and nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I. A total of 10 haplotypes of mtDNA were found in 22 analysed individuals. One haplotype was shared between M. loewi (from Pindos and Duba?nica Mts) and M. armipes, one confined to M. auripes (haplotype III) and M. armipes (VII) and three to M. trebevicensis (VIII, IX and X), M. ruficornis (I, II and IV) and M. loewi (V, VI and VII). Analysis of the population genetic structure parameters showed great differences among analysed species. Different levels of genetic variability suggested that a variety of biological, environmental and/or historical factors had influenced these hoverfly populations. The unweighted pair group method with arithmetic average dendrogram constructed using allozyme data suggested that M. loewi was the most divergent species in comparison with M. armipes, M. auripes, M. ruficornis and M. trebevicensis. Clear separation of the populations ((((M. armipes + M. auripes) + M. ruficornis) + M. trebevicensis) + M. loewi) was observed. The parsimony analysis of the M. ruficornis group using Merodon avidus as outgroup resulted in three equally parsimonious trees, and the strict consensus presented the following relationships ((((M. loewi + M. armipes) + (M. auripes)) + (M. trebevicensis)) + (M. ruficornis)))). The uncorrected interspecies pairwise sequence divergences ranged from 1.69% (between haplotype III of M. armipes and haplotype V of M. loewi) to 4.94% (between M. ruficornis and M. trebevicensis).     

温度对双委夜蛾实验种群生长发育及繁殖的影响

【目的】双委夜蛾Athetis dissimilis(Hampson)是近几年在中国大陆新发现的农业害虫,与二点委夜蛾Athetis lepigone(Mschler)形态相似,危害特点相同。明确温度对其生长发育的影响,对该害虫的预测预报和有效防控具有重要的指导意义。【方法】在光周期16L∶8D,RH 70%±10%的实验室条件下,设置17,21,25,29和33℃5个恒定温度,饲喂人工饲料,研究温度对双委夜蛾发育历期、死亡率及繁殖的影响,并计算各虫态的发育起点温度和有效积温。【结果】在17~33℃范围内,双委夜蛾均可以完成整个世代,各虫态发育历期随温度的升高而缩短;17和21℃下,双委夜蛾幼虫有7个龄期,而25℃以上时幼虫只有6个龄期。25℃下双委夜蛾死亡率最低(21.00%),单雌产卵量最高(763.95粒)。整个世代的发育起点温度和有效积温分别为9.38℃和1 015.36日·度。雌雄虫寿命和产卵期随温度的升高逐渐缩短,且各温度下雌虫寿命均较雄虫长,性比(雄雌比)均在1.18~1.20之间。【结论】25℃是双委夜蛾实验种群生长发育和繁殖的适宜温度。     

温度对微小花蝽生长发育和繁殖的影响

【目的】明确温度对微小花蝽Orius minutus生长发育和繁殖的影响。【方法】本研究以腐食酪螨Tyrophagus putresceniae为猎物,分别在5个恒温(15,20,25,30和35℃)条件下室内饲养,调查了温度对微小花蝽各虫态发育历期、存活率、成虫繁殖力以及种群参数的影响。【结果】在15~35℃范围内,各虫态平均发育历期均随温度升高而缩短,15℃下完成一个世代发育需要52.45 d,而35℃下仅需14.85 d。直线回归分析表明,微小花蝽世代发育起点温度为8.89℃,有效积温为359.20日·度。世代存活率和单雌平均产卵量均在25℃时最高,分别为17.07%和41.00粒。种群趋势指数在15℃和35℃下小于1,种群呈负增长;20~30℃下大于1,且25℃时最高,为3.92。净增殖率、内禀增长率和周限增长率均在25℃时最高,分别为3.32,0.04和1.04;种群世代周期以15℃时最长,为57.76 d,35℃时最短,为17.50 d。【结论】取食腐食酪螨的微小花蝽发育适宜温度范围为25~35℃,存活、繁殖和种群增长的最适温度均为25℃。这些结果为利用腐食酪螨人工饲养微小花蝽提供了基础参考数据。     

红棕象甲发育起点温度及有效积温的测定

在室内恒温条件下,观察了不同温度对棕榈红棕象甲Rhynchophorus ferrugineus Fabricius生长发育的影响,并用直线回归法测得产卵前期、卵、幼虫、蛹和全世代的发育起点温度分别为(16.11±1.44)、(14.10±0.56)、(15.28±0.21)、(14.89±0.24)和(14.15±0.54)℃;有效积温分别为(31.86±1.65)、(748.60±15.79)、(417.94±20.80)和(1215.50±28.56)日·度。红棕象甲的各虫态和全世代发育历期随温度的升高而缩短,在测定的温度范围内,全世代发育历期与温度的关系符合指数函数:y=3343e-0.1279x。     

Effects of photoperiod and temperature on the development and diapause of the bark beetle Ips typographus

Abstract:  Diapause was induced in a Central European population of Ips typographus grown at 20°C when the day length decreased below 16 h [50% diapause incidence occurred in the 14.7:9.3 h L:D (light:dark) regime]. The non-diapausing adults fed on days 2–6 and 10–14 after the ecdysis and swarmed after the second feeding bout with chorionated eggs in the ovaries and sperm in the spermiducts. Neither gonads nor the flight muscles matured and no swarming occurred in the diapausing adults. The development from egg to adult took about 34 days in both 18:6 h (no diapause) and 12:12 h L:D (diapause) regimes, but it was extended by up to 30% without diapause induction when only larvae or pupae were exposed to L:D 12:12 h. Diapause was induced in insects reared at L:D 12:12 h through the last larval and the pupal instars and/or in the adult stage. Temperature ≥ 23°C prevented diapause induction at L:D 12:12 h but diapause occurred at L:D 14:10 h associated with 26:6°C thermoperiod. The effect of thermoperiods on the developmental rate requires further research. Exposure of the non-diapausing adults to 5°C for several days blocked feeding and evoked a diapause-like state, whereas diapausing adults fed and their gonads slowly developed at this temperature. Diapausing adults exposed in forest to low night temperatures and transferred in October to 20°C readily reproduced at 18:6, but not 12:12 h L:D photoperiods. After 2-months at 5°C and darkness, they became insensitive to the photoperiod, matured and most of them also swarmed at 20°C in the 12:12 h L:D regime. In a Scandinavian population, diapause occurred at 18:6 h L:D and was terminated either by exposure to 5°C or by very long photoperiod (L:D 20:4 h) combined with high temperature (23°C).     

Parental and direct effects of photoperiod and temperature on the induction of larval diapause in the blow fly Lucilia sericata

Abstract.  Lucilia sericata (Meigen) (Diptera: Calliphoridae) shows a facultative diapause in the third, and final larval, instar after the cessation of feeding. The effects of photoperiod and temperature on the induction and duration of diapause were examined in parental (G0) and current (G1) generations. Insects of the G0 generation were reared under four combinations of conditions, involving two photoperiods, LD 16 : 8 and LD 12 : 12 h, and two temperatures, 25 and 20 °C. The G1 generation, present in the eggs laid by these insects, were transferred to 10 combinations of conditions, involving the above two photoperiods and five temperatures, 25, 20, 17.5, 15 and 12.5 °C. In the G1 generation, the time from hatching to cessation of feeding was significantly affected by temperature only, whereas the induction of diapause was influenced by both photoperiod and temperature experienced by the G0 as well as the G1 generation. Short-day and low-temperature conditions in the G0 and in the G1 generation had diapause-inducing effects. In this species, it is likely that, for purposes of acquiring reliable seasonal information, induction of diapause is sensitive to environmental factors both in the G0 and G1 generations. The function of high-intensity diapause, induced by short-day conditions and high temperature in the parental generation, appeared to be the prevention of accidental pupariation in warm autumn weather.     

Effect of temperature on development and survival in Delias nigrina (Fabricius) (Lepidoptera: Pieridae)

Abstract The effect of temperature on rate of development and survival of the immature stages of a subtropical population of the black jezebel, Delias nigrina , was studied under laboratory conditions at a range of constant temperatures. Mean developmental times from first-instar larva to adult varied from 29 days at 27°C to 52 days at 19°C; the development threshold temperature and thermal constant were estimated to be 9°C and 494 degree-days, respectively. Larval developmental rates reached physiological maximum at the higher temperatures tested (25−27°C). Pupal development, by contrast, was not affected in the same way as larvae by higher temperature. Survival of the immature stages varied inversely with temperature: survival was highest at 19°C and significantly reduced at 27°C. Mortality at the higher temperature was attributable mainly to final-instar larvae and pupae. These findings indicate that, compared with other tropical pierids that have been studied, D. nigrina has: (i) a comparatively low temperature threshold; (ii) a slow rate of development; and (iii) a poor tolerance to moderately high temperatures. Physiologically, these features are more characteristic of a temperate butterfly than a tropical one. This physiological response appears to be reflected by the temperate nature of the genus as a whole, which may be related to its period of origin and evolution during past climatic events.     

温度对栎黄枯叶蛾生长发育及繁殖的影响

【目的】栎黄枯叶蛾Trabala vishnou gigantina是近年在沙棘Hippophae rhamnoides林中大面积暴发的一种食叶害虫,以幼虫取食叶片,导致沙棘长势衰弱甚至死亡。本研究旨在明确温度对栎黄枯叶蛾生长发育及繁殖的影响,以便对其进行预测预报及采取防治措施。【方法】分别在5个恒温(19,22,25,28和31℃)条件下研究了温度对栎黄枯叶蛾各虫态发育历期、取食量、交配率、产卵、寿命等的影响。【结果】在19~31℃温度范围内,随着温度升高,各虫态发育历期逐渐缩短。卵、幼虫、蛹、产卵前期和全世代的发育起点温度分别为9.24±0.45,10.85±0.87,14.56±0.85,9.65±0.54和10.48±0.52℃,有效积温分别为341.22±9.54,1 285.64±17.65,445.35±8.65,13.34±1.25和2 085.35±25.84日·度。幼虫总取食量和交配率与温度变化关系不大,而成虫的产卵量在22,25和28℃下明显高于其他温度,成虫寿命与温度呈负相关。【结论】22~28℃之间是栎黄枯叶蛾较为理想的生长发育和繁殖温度。研究结果为生产上合理防治该害虫提供了参考依据。     

Visualizing the postembryonic development of Sarcophaga peregrina (flesh fly) by NMR microscopy

The postembryonic development of the flesh fly was studied using high resolution nuclear magnetic resonance imaging. Because this development occurs in a puparium, this process cannot be observed directly using standard histological techniques. The remodelling of histolysing larval tissues to developing imaginal tissues including the yellow body, a transient alimentary structure, and the integration of the developed adult structure were revealed in the images. Most surprisingly it was found that a large gas space that forms in the central region of the prepupa moves to the dorso-anterial region in less than 5 min due to the larval–pupal apolysis together with separation of the developing pupal epidermis from the puparium.     

Temperature related effects on embryonic development of the Mediterranean locust, Dociostaurus maroccanus

Laboratory studies were conducted to assess the effect of temperature on the development of the eggs of Dociostaurus maroccanus (Thunberg) (Orthoptera, Acrididae) during anatrepsis (stages I–XIV) and during catatrepsis (stages XV–XX). The developmental rates of anatrepsis were studied at five constant temperatures ranging from 10 to 30°C. Egg development occurred over the entire range but at 10°C the embryos were unable to complete anatrepsis. The relationship between temperature and developmental times for completing anatrepsis was analysed by the non‐linear Logan type III model. The optimal temperature estimated for the development of eggs during anatrepsis was 24.7°C; the lower and upper thermal thresholds were 9°C and 31°C, respectively. Once the embryos completed anatrepsis, only those incubated at 15°C continued morphogenesis beyond stage XIV (diapause stage) without a low‐temperature exposure period. The developmental rate of catatrepsis was studied at four constant temperatures ranging from 15°C to 30°C after exposure to low‐temperature, 10°C, for 30, 60 or 90 days. For catatrepsis, temperature and developmental time were linearly and inversely related. Linear regression was used to estimate the lower developmental threshold and the degree days requirements for catatrepsis. Both decreased with longer exposure to the low temperature; the former from 13.8°C to 10.5°C and the latter from 212.8 to 171.5 degree days, following 30 and 90 days at 10°C, respectively. Our results improve the ability of decision support systems for Mediterranean locust pest management by providing better forecasts to land managers and pest advisors.     

温度对巨膜长蝽生长发育与繁殖的影响

【目的】近年来巨膜长蝽Jakowleffia setulosa (Jakovlev)由稳定种群的荒漠昆虫上升为暴发性发生并迁移至农区危害的农业害虫。由于缺乏巨膜长蝽生物学基础研究,给监测预警及综合防治带来许多困难。本研究旨在探明温度对巨膜长蝽发育和繁殖的影响。【方法】本实验以白茎盐生草Halogeton arachnoideus Moq.为寄主植物,分别在7个恒温（13,18,23,28,33,35和37℃）下研究了温度对巨膜长蝽各虫态平均发育历期、发育速率、成活率、产卵量和种群参数的影响。【结果】在13~37℃范围内,各虫态的发育历期随温度的升高而缩短,13℃完成一个世代发育需要82.63 d,37℃只需要14.61 d。各虫态的发育速率（V）与温度（T）的关系均符合多项式回归模型,且极显著相关。采用直接最优法分析,巨膜长蝽世代的发育起点温度为8.30℃,有效积温为555.77日·度,在宁夏一年可发生2代。巨膜长蝽世代存活率均在33℃时最高,为35.44%。28～37℃之间单雌产卵量较多,达到10粒以上,通过方程拟合得到理论上雌虫产卵最适温度为34.59℃,产卵量最高可达到16.73粒/雌;种群趋势指数在13℃为零,18～23℃小于1,种群呈负增长;28～37℃大于1,且33℃时最高,为2.77;净增殖率、内禀增长率及周限增长率均在37℃时最高,分别为7.24, 0.3912和1.4787;种群世代周期以13℃时最长,为45.8936 d,37℃时最短,为5.0608。【结论】巨膜长蝽在28～35℃下存活率、增长指数和繁殖力较高,说明该温度范围是巨膜长蝽生长发育和繁殖的适宜温度。本研究为有效开展巨膜长蝽的监测预报及综合防控提供了科学依据。     

The effect of temperature on the development times of eggs,naupliar and copepodite stages of five species of cyclopoid copepods

The duration times of eggs, combined naupliar instars and of the different copepodite stages of five species of cyclopoid copepods — Acanthocyclops robustus, Cyclops vicinus, Diacyclops bicuspidatus, Mesocyclops leuckarti, and Thermocyclops crassus — were investigated at five different temperatures. The five species can be divided in two groups: two species, C. vicinus and D. bicuspidatus, adapted to cold water conditions and three species, A. robustus, M. leuckarti and T. crassus adapted to warm water conditions. The cold water species showed a faster egg development than M. leuckarti and T. crassus at 5–15 °C. The eggs and instars of the warm water species M. leuckarti tend to develop faster than those of the former two species at higher temperatures. A. robustus showed the shortest egg and instar development at 10–25 °C. The warm water species T. crassus produced no eggs at 10 °C and temperatures below. At higher temperatures (20, 25 °C) the egg and instar duration times were similar or longer than those of the other species. When cultured in total darkness a great part of the C_IV respectively C_V copepodites of the summer forms entered arrest and the percentage of copepodites that showed an arrest of development was highest at lowest temperatures. The present results are compared with data from literature and differences are discussed.     

Effect of daylength and temperature on the larval diapause of the sunflower moth, Homoeosoma electellum

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.     

Effects of temperature on the post-diapause embryonic development and the hatching time in three grasshopper species (Orth., Acrididae)

A study was conducted to determine the effects of six constant temperatures (15, 20, 25, 30, 35 and 40°C) on the post‐diapause embryonic development and the hatching time in three grasshopper species –Omocestus haemorrhoidalis (Charp.), Calliptamus abbreviatus Ikonn. and Chorthippus fallax (Zub.) – from the Inner Mongolian steppe. The results indicate that the species differ in the developmental rates, survival curves and cumulative hatching probabilities. The eggs of O. haemorrhoidalis had the fastest developmental rate with a low developmental threshold temperature of 9.9°C and the sum of effective temperature (SET) 211.2 degree‐days (DD). The corresponding values were 10.9°C and 210.6 DD for C. abbreviatus, 10.5°C and 240.2 DD for Ch. fallax respectively. The SET at which 50% of post‐diapause eggs hatched were 252.0 DD for O. haemorrhoidalis, 262.8 DD for C. abbreviatus, and 273.3 DD for Ch. fallax. The predicted maximal hatch ability of O. haemorrhoidalis (91.17%), C. abbreviatus (75.67%) and Ch. fallax (94.07%) occurred at 23.7, 29.0 and 31.3°C, respectively. The thermal death points of each species were reached at 43.3, 45.0 and 48.6°C. The optimal temperature ranges were 12.2–35.2°C for O. haemorrhoidalis, 21.7–36.3°C for C. abbreviatus and 20.9–41.7°C for Ch. fallax respectively. These results suggest that O. haemorrhoidalis adapt to hatch at a lower temperature range, C. abbreviatus adapt to mid‐temperature range, while Ch. fallax adapt to hatch at a higher temperature range. Although the SET of Ch. fallax is more than that of the other two species, it is not sufficient to explain the hatching sequence of the species in springtime. The results also indicate that Ch. fallax and O. haemorrhoidalis have wider adaptive temperature range than C. abbreviatus.     

Laboratory studies on aestivation in the cabbage root fly (Delia radicum)

Laboratory experiments at 16°–30°C showed that the cabbage root fly can only be induced into aestivation during the early part of the pupal stage. The relationship between the percentage of pupae entering aestivation (y) and the average daily temperature (T) was the same under both constant and alternating temperatures. The percentage of pupae entering aestivation at a particular temperature was given by y=13T–255. An additional 13% of the pupae entered aestivation for each degree rise between 20° and 27°C. There was no constant period of arrested development following the induction of aestivation. Aestivating pupae started to develop into flies as soon as the temperature fell below 20°C. The reinduction of aestivation occurred more readily than the initial induction. Insect survival was not reduced after a month of aestivation. The effects of aestivation on forecasting the time of the second (summer) generation of flies are discussed.

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Étude au laboratoire de l'estivation de la mouche du Chou (Delia radicum)

Résumé Au laboratoire, à 10°–30°C, l'induction de l'estivation ne peut être obtenue qu'avec des pupes formées depuis peu.Le rapport pourcentage de pupes entrant en estivation (y) température journalière moyenne (T) a été le même, que la température soit constante ou alternée. La relation entre la température et ce pourcentage est donnée par y=13 T–255. Le pourcentage de pupes entrant en estivation a augmenté de 13% pour chaque élévation d'un degré entre 20° et 27°C. L'estivation une fois induite, la période d'arrêt de développement n'est pas constante. Dès que la température est devenue inférieure à 20°C, la formation d'imagos a commencé dans les pupes en estivation. Une nouvelle estivation a été plus facile à provoquer que l'estivation initiale. Le taux de survie des insectes n'avait pas diminué après un mois d'estivation. La discussion examine l'utilisation des conséquences de l'estivation dans la prédiction de la seconde génération d'adultes: génération d'été.

     

Maternal temperature has different effects on the photoperiodic response and duration of larval diapause in blow fly ( Calliphora vicina ) strains collected at two latitudes

Abstract .The blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) has a wide distribution across northern and temperate Europe. It has a facultative, maternally-induced larval diapause in response to short days. The photoperiodic response, measured at 15 and 20°C, of two populations was compared. A southern population (originating at 51° N) was sensitive to temperature at all daylengths; the incidence of diapause was greatly reduced at 20°C compared with 15°C. The photoperiodic response of a northern population (from 65° N) was sensitive to temperature only in long days; in short days (< 14 h of light) the response of this strain was identical at each temperature.
Variation in parental photoperiod and temperature were found to affect the duration of larval diapause, indicating a role for maternal effects in diapause intensity as well as incidence. However, the between-strain variation was greater than that within strains, indicating qualitative differences in diapause response. These differences may arise from the ecological conditions at the points of origin of the two strains. The northern strain from the harsher climate has a more intense diapause that follows a relatively temperature-insensitive photoperiodic response. In contrast, the southern strain has a shallow diapause and its photoperiodic response may be overridden by the experience of concurrent high temperature.     

温度对豆荚野螟实验种群的影响

作为豆科蔬菜上的重要害虫 ,豆荚野螟 Maruca testulalis Geyer能够对豆科蔬菜造成严重危害。研究温度对豆荚野螟不同虫期发育的影响 ,可以有利掌握其种群动态 ,以便进行有效控制。研究了室内不同温度条件下豆荚野螟的生长发育情况 ,发现在2 0～ 32℃温度范围内 ,随温度上升发育历期缩短 ;对于不同的生活史阶段 ,豆荚野螟卵、1～ 4龄幼虫、蛹及整个世代受温度影响显著 ;并计算得出完成全世代发育起点温度为 7.84℃ ,有效积温达 4 74 .2 0℃。通过内禀增长率参数的比较 ,认为各参数与温度的关系均达到极显著相关 ,以 2 9～ 32℃为豆荚野螟最适温度