不同温度对中国对虾生长及能量收支的影响

研究了18～34℃6个不同恒温下中国对虾(Fenneropenaeus chinensis)的生长、饵料转化率及能量收支。结果表明,中国对虾的体重及能量特定生长率分别变动在1．22％～3．27％和1．33％～1．45％之间,在18～31℃温度范围内随温度升高而升高,34℃下则显著下降．对虾的摄食量及对饵料的消化率总体上随温度升高而升高,但在34℃下则有所降低;饵料重量转化率和能量转化率分别在28．99％～53．09％和15．70％～7．24％之间,总体上随温度升高而有所下降．根据拟合的多项式方程推算得到的中国对虾的最佳生长温度为29．7℃,生长能和呼吸能的变化主导着中国对虾的能量收支模式,随温度升高生长能占摄食能的比例逐渐降低,而呼吸能比例则逐渐升高。本研究表明,对虾在适宜温度下获得的较高生长率主要归因于较高的摄食量和食物消化率。     

温度对胡萝卜微管蚜生长发育繁殖的影响

【目标】明确温度对胡萝卜微管蚜Semiaphis heraclei(Takahashi)生长发育和繁殖的影响。【方法】在室内5个温度梯度下(19、22、25、28、31℃)观察并比较胡萝卜微管蚜的发育历期、存活率、存活寿命及产仔量。【结果】在19?31℃范围内,胡萝卜微管蚜各龄期及完整世代的发育历期均随着温度的升高而缩短,完成一个世代分别需要22.17、17.13、12.57、10.03和7.83 d。温度与发育速率呈极显著相关(P<0.01,r>0.8),温度越高发育速率越快。胡萝卜微管蚜4个若蚜期和世代的发育起点分别为14.15、13.87、13.64、15.06、12.92℃,有效积温分别为29.98、29.30、28.54、24.00和144.21日?度。建立了胡萝卜微管蚜各个发育阶段的历期预测式。在5个恒温下胡萝卜微管蚜1?4龄及世代的存活率随温度的变化而小幅波动。在19?31℃范围内,该蚜虫世代的存活率分别为40.0%、52.5%、62.5%、60.0%和47.5%。25℃该蚜虫的存活率相对较高,1?4龄及世代的存活率分别为82.5%、81.8%、92.6%、100%和62.5%。在相同温度条件下该蚜虫不同发育阶段的存活率存在差异。存活寿命随着温度的升高而缩短,19℃时寿命最长,为33.30 d,31℃时寿命最短,为15.40 d。产仔期随着温度的升高而缩短,19℃时产仔期为11.13 d,31℃时为7.57 d。在19?31℃范围内,该蚜虫的单雌产仔总量分别为26.33、27.93、32.53、27.13和17.93头。【结论】温度是影响胡萝卜微管蚜的生长发育、存活和繁殖的重要因素。25℃时胡萝卜微管蚜各龄期及世代的发育历期较短,存活率较高,单雌产仔总量最大。25℃较适合该蚜虫生长发育和繁殖。     

Effects of temperature on development of vedalia beetle, Rodolia cardinalis (Mulsant)

The effect of temperature on the development of the vedalia beetle, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae), fed Icerya purchasi Maskell (Homoptera: Margarodidae) under controlled laboratory conditions was studied. Adults exposed to temperatures of 25, 28, 31, 34, and 37 °C for 72 h showed 95–100% survival, however egg production was significantly reduced at 34 and 37 °C. In addition, eggs maintained at 34 °C showed reduced hatch and survival of larvae, and eggs held at 37 °C failed to hatch. The duration of each developmental stage and survival of each stage were measured at 10, 14, 18, 22, and 25 °C. There was no egg eclosion at 10 °C. The developmental time from egg to adult emergence decreased from 79 to 18 days for temperatures from 14 to 25 °C. The sex ratio was unaffected by these temperatures. The lower developmental temperature threshold of R. cardinalis was estimated to be 10.8 °C and the degree–day accumulation was calculated as 279 for development from egg to adult eclosion. These results will guide further research designed to optimize management of vedalia populations in the San Joaquin Valley of California.     

温度对产虫茶昆虫紫斑谷螟生长发育的影响

为探明温度对贵州主要产虫茶昆虫紫斑谷螟Pyralis farinalis (Linnaeus)生长发育的影响, 本研究以白茶Litsea coreana为寄主植物, 分别设置5个恒温（19, 22, 25, 28和31℃）条件, 研究温度对紫斑谷螟卵、 幼虫、 蛹和未成熟期平均发育历期、 发育速率和存活率的影响, 计算各虫态发育起点温度和有效积温。 结果表明： 温度对紫斑谷螟各虫态发育历期、 发育速率和存活率影响显著。 在19 ~ 31℃范围内, 各虫态的平均发育历期均随温度的升高而缩短, 卵期、 幼虫期、 蛹期及未成熟期均在31℃达到最小值, 分别为4.56±0.24, 43.33±1.50, 7.89±0.20和55.78±1.69 d。 紫斑谷螟各虫态发育速率与温度呈二次回归关系, 且极显著相关。 此外, 温度显著影响各虫态存活率, 卵的存活率在28℃时最高, 为93%; 幼虫和蛹的存活率则在25℃最高, 分别为88%和93%; 温度过高或过低均不利于其生长发育。 由直接最优法计算得到紫斑谷螟卵期、 幼虫期、 蛹期及未成熟期的发育起点温度分别为13.30, 15.48, 13.19和14.82℃, 有效积温依次为88.36, 679.51, 159.73和952.04日·度。 这些结果为紫斑谷螟的繁殖提供了基础参考数据, 对指导虫茶生产有实用参考价值。     

Survival, development and food energy partitioning of nase larvae and early juveniles at different temperatures

Survival was generally high, 94–100%, for newly hatched larvae of the nase Chondrostoma nasus held at 10, 13, 16, 19, 22, 25 and 28° C up to day 66 post-fertilization. The developmental rate decreased with age and increased with temperature. Specific growth rates increased with temperature; within one temperature range growth rate decreased with ontogenetic development. Food consumption and respiration increased with temperature and body size. A temperature increase from 25 to 28° C resulted in slightly reduced survival, minor acceleration of developmental growth and respiration rates, and impeded skeleton formation. Growth efficiency of consumed energy decreased throughout the larval period from 55 to 67% at the first larval stage (L1) to 36–48% at the first juvenile stage (J₁). A similar trend for assimilation efficiency and its utilization for growth was observed. The constant temperatures required by larval nase ranged from a minimum 8–10° C to a maximum 25–28° C. A shift of optimum temperatures, 8–12, 13–16, 15–18, 19 and 22° C for nase spawning, embryonic development, yolk feeding larvae, early externally feeding larvae and, late larvae and juveniles, respectively, paralleled the spring rise in the river water temperature. Larval and juvenile nase show high survival, growth and energy conversion efficiencies compared with other fish species. On the other hand, low survival rates and growth can be attributed to external perturbations; thus, young nase may be considered a good indicator of the environmental and ecological integrity of river systems.     

温湿度对稻纵卷叶螟卵的联合作用

为了探讨温湿度在稻纵卷叶螟Cnaphalocrocis medinalis （Guenée）种群发展中的作用, 通过室内实验调查了不同温度和湿度组合下该蛾卵的发育历期、 胚胎发育情况、 孵化率和卵粒重量的变化。结果表明： 在相同温度下卵历期随相对湿度的增大而缩短, 孵化率随相对湿度的加大而提高。在22℃下低于46%的相对湿度显著降低了卵的孵化率, 而在25～34℃下低于66%的相对湿度会引起孵化率的显著降低, 37℃下卵无论在何种湿度中均不能孵化。在50%左右的低湿条件下, 温度高于28℃后卵也不能孵化。温度在22～31℃和相对湿度在77%～100%范围内, 卵的孵化率无显著差异, 这属于稻纵卷叶螟卵的适宜温湿度范围。稻纵卷叶螟卵的发育起点温度和有效积温分别为10.1±0.6℃和63.7±3.5日度。卵的孵化率（Y）与温湿系数（RH/T）间呈显著的逻辑斯蒂曲线关系Y=0.8662/[1+exp(17.4084-7.5714×RH/T)]。温湿系数在2.34以下时卵孵化率将低于50%, 而达到3.0左右时孵化率接近最高值。结论认为, 低湿造成的稻纵卷叶螟卵重量显著降低、 卵粒干瘪、 胚胎发育受阻是致死卵的主要原因。     

Effect of temperature on the development of the immature stages ofBembidion lampros [Coleoptera: Carabidae]

The effects of temperature on survival and development of immature stages ofBembidion lampros were examined under controlled conditions in the laboratory. The duration of development was examined at 5°C, 12°C, 17°C, 19°C, 22°C, 25°C, 30°C and 32°C and found to be inversely related to temperature. Between 12°C and 30°C there was a significant difference in duration of egg development, but no significant difference in percentage of eggs hatched. The upper and lower lethal limits for egg development were estimated (c 31°C and 4°C respectively). There are 3 larval instars and one pupal stage. Development of larva plus pupa required a minimum of 20.9 days at 30°C. Between 22°C and 30°C survival from larva to the adult stage was 80%.      

Effect of temperature on the demography of Galerucella birmanica (Coleoptera: Chrysomelidae)

Studies on the effect of temperature on the development of the water chestnut beetle, Galerucella birmanica Jacoby were carried out in the laboratory at seven different temperatures: 16 °C, 19 °C, 22 °C, 25 °C, 28 °C, 31 °C and 34 °C. The developmental time decreased with increase in temperature. The developmental time at 16 °C, 19 °C, 22 °C, 25 °C, 28 °C, 31 °C and 34 °C was 96.60, 80.68, 58.96, 43.48, 35.03, 30.08 and 28.02 days for the period from egg hatching to adult emergence, respectively. The developmental threshold estimated for a generation by linear regression was 10.36 °C. The fecundity per female at 22 °C, 25 °C, 28 °C, 31 °C and 34 °C was 102.3, 134.5, 141.2, 130.1 and 116.2 eggs, respectively. Oviposition period ranged from 15.6 days at 22 °C to 8.6 days at 34 °C. Hatchability of eggs was highest at 31 °C with 76.9% and lowest at 34 °C with 57.1%. The highest generation survival rate was 65.3% at 31 °C, and the intrinsic rate of natural increase ( r _m) for G. birmanica was the highest at 34 °C.     

Influence of temperature, photoperiod and humidity on oviposition and egg hatch of the root-feeding flea beetle Longitarsus bethae (Chrysomelidae: Alticinae), a natural enemy of the weed Lantana camara (Verbenaceae)

The root-feeding flea beetle Longitarsus bethae Savini & Escalona, was introduced into South Africa as a candidate biological control agent for the noxious and invasive weed, Lantana camara L. As part of the study to predict the beetles' survival in its new range, the influence of climatic conditions on its egg development and reproductive performance were investigated in the laboratory. The threshold temperature (T degrees) and degree-days (DD) required for egg hatch were determined after exposing the eggs to various constant temperatures (12, 17, 22, 27 and 32 degrees C) in separate growth chambers. The DD required for egg hatch was 178.6, and the temperature threshold required for egg hatch was 11.3 degrees C. Survival of eggs varied from 27 to 56% at 32 and 17 degrees C, respectively, and was optimum between 17 and 25 degrees C. Oviposition was examined under high and low relative humidity (RH) regimes while egg hatch was determined at six RH levels, each maintained in a separate controlled growth chamber set at a constant temperature (25 degrees C). Whilst RH had no influence on oviposition, eggs were highly susceptible to aridity, and continuous exposure to relative humidity below 63% for more than three days was wholly lethal at 25 degrees C. Optimum egg hatch occurred at RH between 85 and 95% for up to 12 days. The effect of day length on oviposition and subsequent egg hatch was investigated under two photoperiod regimes. Neither oviposition nor subsequent egg hatch was influenced by photoperiod. The knowledge obtained will be useful for mass rearing as well as field release programmes for L. bethae.     

Development rates of two Xenopsylla flea species in relation to air temperature and humidity

The rate of development of immature fleas, Xenopsylla conformis Wagner and Xenopsylla ramesis Rothschild (Siphonaptera: Xenopsyllidae) was studied in the laboratory at 25 degrees C and 28 degrees C with 40, 55, 75 and 92% relative humidity (RH). These fleas are separately associated with the host jird Meriones crassus Sundevall in different microhabitats of the Ramon erosion cirque, Negev Highlands, Israel. This study of basic climatic factors in relation to flea bionomics provides the basis for ecological investigations to interpret reasons for paratopic local distributions of these two species of congeneric fleas on the same host. Both air temperature and RH were positively correlated with duration of egg and larval stages in both species. Change of humidity between egg and larval environments did not affect duration of larval development at any temperature. At each temperature and RH, the eggs and larvae of X. ramesis did not differ between males and females in the duration of their development, whereas female eggs and larvae of X. conformis usually developed significantly faster than those of males. For both species, male pupae developed slower than female pupae at the same air temperature and RH. Air temperature, but not RH, affected the duration of pupal development. At each humidity, duration of the pupal stage was significantly longer at 25 degrees C than at 28 degrees C: 15.3+/-1.7 vs. 11.7+/-1.2 days in X. conformis; 14.1+/-2.0 vs. 11.5+/-1.7 days in X. ramesis, with a significantly shorter pupal period of the latter species at 25 degrees C. These limited interspecific bionomic contrasts in relation to basic climatic factors appear insufficient to explain the differential habitat distributions of X. conformis and X. ramesis.     

变温对甘蓝夜蛾生长发育和繁殖的影响

【目的】明确自然变温环境对甘蓝夜蛾Mamestra brassicae生长发育和繁殖的影响,深入研究其对环境温度的适应性。【方法】在13~25℃(日平均19℃), 16~28℃(日平均22℃), 19~31℃(日平均25℃), 22~34℃(日平均28℃)和25~37℃(日平均31℃) 5个梯度变温条件下,以大豆Glycine max植株叶片为寄主材料饲养甘蓝夜蛾卵,测定其各虫态发育历期、发育速率、成虫繁殖力及发育起点温度和有效积温。【结果】变温范围为13~25℃时甘蓝夜蛾发育历期最长,世代发育历期为65.93 d,显著长于其他变温处理。且随温度升高,其发育历期缩短,变温范围为22~34℃时,该虫发育历期最短,世代发育历期为38.46 d,显著短于其他变温处理。在变温范围为25~37℃时,该虫不能正常完成个体发育。在日平均温度(T)19~28℃范围内(最大温差12℃),甘蓝夜蛾卵、幼虫及蛹期的发育速率随温度升高而加快,且各个虫态发育速率(V)拟合方程均符合线性方程模型：V_卵期=0.125+0.048T, V_幼虫期=0.023+0.012T, V_蛹期0.027+0.013T, V_成虫=0.073+0.47T。甘蓝夜蛾雌雄成虫的寿命随着日平均温度的升高而逐渐缩短,雌雄成虫寿命在日变温范围13~25℃时最长,分别为7.91 d和8.00 d;在变温范围22~34℃时最短,分别为3.00 d和3.57 d。甘蓝夜蛾卵、幼虫、蛹、成虫发育起点温度分别为7.98, 6.54, 9.36和10.78℃,有效积温依次为87.00, 607.36, 351.51和108.52 d·℃。16~28℃的变温范围更适合甘蓝夜蛾种群的生存与繁殖,其种群趋势指数I为117.81。【结论】甘蓝夜蛾属于偏低温适应性害虫,对高温环境适应能力较低。研究结果为进一步研究甘蓝夜蛾自然种群发生规律及其发生期、发生量预测预报提供了科学依据。     

Effects of husbandry parameters on the life-history traits of the apple snail, Marisa cornuarietis: effects of temperature, photoperiod, and population density

Abstract. These experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the apple snail, Marisa cornuarietis . The overall objective of the program is to identify suitable husbandry conditions for maintaining multi-generation populations of this species in the laboratory for use in ecotoxicological testing. In this article, we focus on the effects of photoperiod, temperature, and population density on adult fecundity and juvenile growth. Increasing photoperiod from 12 to 16 h of light per day had no effect on adult fecundity or egg hatching and relatively minor effects on juvenile growth and development. Rearing snails at temperatures between 22°C and 28°C did not influence the rates of egg production or egg clutch size. However, the rates of growth and development (of eggs and juveniles) increased with increasing temperature in this range, and when temperatures were reduced to 22°C egg-hatching success was impaired. Juvenile growth and development were more sensitive to rearing density than adult fecundity traits. On the basis of the present results, we conclude that rearing individuals of M. cornuarietis at a temperature of 25°C, a photoperiod of 12L:12D, and a density of <0.8 snails L⁻¹ (with lower densities for juvenile snails) should provide favorable husbandry conditions for maintaining multi-generation populations of this species.     

Egg development, hatching and early life-history of Dissonus manteri (Copepoda), parasitic on the gills of coral trout, Plectropomus leopardus

The early life-history of Dissonus manteri differs markedly from that of Caligidae and from that of its congener Dissonus nudiventris. The uniseriate egg strings are of typical caligid form, but the stage hatching from the egg is a preecdysis nauplius which moults immediately to the copepodid. The empty naupliar cuticle remains tethered to the egg string by a pair of posterior threads which attach to the internal surface of the egg membrane. The duration of egg development is 112 h and the mean duration of hatching is 5.2 h at 25 degrees C. Aeration and water movement are important for successful hatching. Under these conditions, hatching success is 94.8%, but decreases to 48.4% in static water with no aeration. Mean survival time of the copepodid in the absence of a host is 41.4 h at 25 degrees C. The reduction of early free-living stages in the life-cycle and the high survival rate from egg to copepodid could be important in future coral trout aquaculture, since the potential for re-infection by this parasite is very high.     

温度对桃蛀螟生长发育和繁殖的影响

为了明确温度对桃蛀螟Conogethes punctiferalis (Guenée)生长发育和繁殖的影响, 本实验在恒温条件（15, 19, 23, 27和31℃共5个温度梯度）下, 以板栗为寄主食料, 研究了温度对桃蛀螟实验种群生长发育和繁殖的影响。结果表明： 温度对桃蛀螟各虫态的发育历期、 存活率、 蛹重以及种群繁殖力有显著影响。在15~27℃范围内, 各虫态的发育历期均随温度的升高而缩短, 发育速率与温度呈显著正相关。但是, 当温度上升至31℃时, 幼虫生长发育受到抑制, 其发育历期比27℃时延长了1.11 d, 而卵期、 蛹期和产卵前期仍符合随温度升高趋于缩短的趋势。此外, 15℃下桃蛀螟5龄幼虫发育停滞, 表明老熟幼虫的发育起点温度高于其他低龄幼虫。桃蛀螟世代存活率随环境温度变化的大小顺序为23℃>27℃>19℃>31℃, 其中, 23~27℃的存活率较高, 为54.44%~63.56%, 31℃时为4.30%, 说明温度过高或过低均不利于其生长发育。成虫产卵量在23℃时最高, 单雌平均产卵量达55.00粒, 其次为19℃和27℃, 单雌平均产卵量分别为43.30和39.70粒; 31℃下产卵量最少, 仅为20.90粒。由直接最优法计算得到桃蛀螟卵期、 幼虫期、 蛹期、 产卵前期及全世代的发育起点温度分别为10.37, 10.06, 14.27, 7.47和11.85℃, 有效积温依次为70.84, 287.71, 118.42, 58.33和509.06日度。研究结果为桃蛀螟发生期的预测预报提供了基础参考数据, 对指导生产实践有实际的应用意义。     

Development of Aphidius colemani Viereck (Hym.: Braconidae, Aphidiinae) and alterations caused by the parasitism in the host Aphis gossypii Glover (Hem.: Aphididae) in different temperatures

Aphidius colemani Viereck is among the main natural enemies used for biological control of Aphis gossypii Glover. The objective of the present study was to evaluate the development of A. colemani and the alterations caused by the parasitism in the host A. gossypii in different temperatures and to estimate the thermal requirements of the parasitoid. The experiments were carried out in controlled environmental chambers at 16, 19, 22, 25, 28 and 31 +/- 1 degrees C, 70 +/- 10% RH, and 12h photophase. Second-instar nymphs of A. gossypii were parasitized once and kept individually in glass tubes (2.5 cm x 8.5 cm), containing leaf disc of cucumber (2 cm) and 1% water/agar solution. The development time of A. colemani, from oviposition to mummies (11.9, 9.8, 7.7, 6.4 and 6.4 days) and from oviposition to adult (19.4, 16.2, 12.6, 10.5 and 10.7 days) decreased with the increase of the temperature from 16 degrees C to 25 degrees C. The rates of mummies and the emergence of the parasitoid, and its longevity also decreased with the increase of the temperature. Mummies were not produced at 31 degrees C. The lower temperature threshold of A. colemani was 5.94 degrees C and its thermal constant was 200 degrees-day. The alterations caused by the parasitoid in the A. gossypii host were minimized at 31 degrees C, where 98% of the host did not show symptoms of parasitism and produced nymphs. The temperature of 22 degrees C was optimal for the development time of A. colemani.     

Effects of incubation temperature on the energetics of embryonic development and hatchling morphology in the Brisbane river turtle Emydura signata

Incubation temperature and the amount of water taken up by eggs from the substrate during incubation affects hatchling size and morphology in many oviparous reptiles. The Brisbane river turtle Emydura signata lays hard-shelled eggs and hatchling mass was unaffected by the amount of water gained or lost during incubation. Constant temperature incubation of eggs at 24 °C, 26 °C, 28 °C and 31 °C had no effect on hatchling mass, yolk-free hatchling mass, residual yolk mass, carapace length, carapace width, plastron length or plastron width. However, hatchlings incubated at 26 °C and 28 °C had wider heads than hatchlings incubated at 24 °C and 31 °C. Incubation period varied inversely with incubation temperature, while the rate of increase in oxygen consumption during the first part of incubation and the peak rate of oxygen consumption varied directly with incubation temperature. The total amount of oxygen consumed during development and hatchling production cost was significantly greater at 24 °C than at 26 °C, 28 °C and 31 °C. Hatchling mass and dimensions and total embryonic energy expenditure was directly proportional to initial egg mass. Accepted: 18 March 1998     

Effects of temperature and larval diet on development rates and survival of the dengue vector Aedes aegypti in north Queensland, Australia

Immature development times, survival rates and adult size (wing-lengths) of the mosquito Aedes aegypti (L.) (Diptera: Culicidae) were studied in the laboratory at temperatures of 10-40 degrees C. The duration of development from egg eclosion (hatching of the first instar) to adult was inversely related to temperature, ranging from 7.2 +/- 0.2 days at 35 degrees C to 39.7 +/- 2.3 days at 15 degrees C. The minimum temperature threshold for development (t) was determined as 8.3 +/- 3.6 degrees C and the thermal constant (K) was 181.2 +/- 36.1 day-degrees above the threshold. Maximum survival rates of 88-93% were obtained between 20 and 30 degrees C. Wing-length was inversely related to temperature. The sex ratio (female:male) was 1:1 at all temperatures tested (15, 20, 25 and 35 degrees C) except 30 degrees C (4:3). Under field conditions at Townsville and Charters Towers, north Queensland, the duration of immature development varied according to the container position (i.e. shaded or exposed) and the availability of food resources, as well as inversely with temperature. These data indicate that containers with an abundance of organic matter (e.g. those used for striking plant cuttings) or those amongst foliage or under trees (e.g. discarded plastic tubs and tyres) tended to produce the largest adult Ae. aegypti, which had faster development and better immature survival. As such progeny have been linked to a greater risk of dengue transmission, it would seem important to focus on control of such containers.     

Effect of temperature and humidity on development, survival and oviposition in laboratory populations of Eriworm, Philosamia ricini (Boisduval) (Lepidoptera Saturniidae)

Experiments were conducted on laboratory populations of Eriworm, Philosamia ricini Boisduval to study the effect of temperature and humidity on development, growth, survival and oviposition. Experiments were performed at four different temperatures (22 +/- 2 degrees C, 26 +/- 2 degrees C, 28 +/- 2 degrees C and 34 +/- 1 degrees C) each with three different humidities (50%, 70% and 90% relative humidity). Shortest developmental period (42 days) was observed in 28 +/- 2 degrees C and 70% RH. Longest developmental period was (63.6 days) observed in 22 +/- 2 degrees C at 50% RH. Highest larval weight (9.1 g) was found in 28 +/- 2 degrees C at 70% RH. Best pupal weight was observed in 26 +/- 2 degrees C at 70% RH. Weight of silk material was found to be maximum in 26 +/- 2 degrees C at 70% RH. Survival was best in 28 +/- 2 degrees C and 26 +/- 2 degrees C at 70% RH. Oviposition was found to be highest in 28 +/- 2 degrees C at 70% RH.     

Effect of temperature on the development of the West Indian sweet potato weevil, <Emphasis Type="Italic">Euscepes postfasciatus</Emphasis> (Fairmaire) (Coleoptera: Curculionidae) on an artificial diet

The relationship between temperature and the development of the West Indian sweet potato weevil, Euscepes postfasciatus, on an artificial larval diet containing powdered sweet potato root, was examined at different fixed temperatures from 22 to 31°C. The developmental periods for egg, larvae, and pupae stages shortened in correlation with increased temperature. The thermal constant was 769.2 degree-days and the developmental zero for female and male was 11.1 and 11.7°C, respectively. Although we can rear this weevil at temperatures ranging from 22 to 31°C, rearing temperatures should be kept between 25 and 28°C because the developmental stages were too long at 22°C and the larval period was delayed at 31°C. The basis for these developmental data will be a useful key factor in designing a plan to eradicate the weevil by using a mass-rearing system and SIT.     

低温对小菜蛾实验种群的影响

研究了低温(<8℃)对小菜蛾的发育、存活和繁殖的影响结果表明,卵和蛹在4℃和6℃下死亡率随处理时间的延长而增加,在分别处理55d和70d后,卵和蛹全部死亡;经4℃和6℃处理的蛹,在16℃下羽化成虫的平均产卵量随处理时间的延长而减少,处理45d时,产卵量均为0小菜蛾幼期各虫态在0℃以下,死亡率随低温强度加大和处理时问的延长而增高就耐寒力而言,3龄幼虫和蛹最强,其次是2龄和4龄幼虫,卵和1龄幼虫的耐寒力最弱不同低温和时间处理小菜蛾幼期虫态对其后继虫态的发育历期有较大影响,总体说来,经过处理的小菜蛾幼期虫态,其后继虫态的发育历期普遍延长,一般处理某一虫态对其相邻虫态发育历期的影响最大小菜蛾蛹经低温处理后其羽化成虫的产卵量随着蛹期所经历低温强度的增强和时间延长而减少。