Diapause development in early and late emerging phenotypes of Delia floralis

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.     

Comparative demography of Liriomyza sativae Blanchard （Diptera： Agromyzidae） on cucumber at seven constant temperatures

Reproduction and population parameters of vegetable leafminer, Liriomyza sativae Blanchard were measured on cucumber （Cucumis sativus L.） at seven constant temperatures （10, 15, 20, 25, 30, 35 and 40℃）. No eggs were found at 10℃ and flies died after exposure to 40℃. The significantly highest intrinsic rate of natural increase （rm）, net reproductive rate （R0） and finite rate of increase （λ） ofL. sativae were obtained at 25℃ as 0.196, 52.452, and 1.216, respectively. The above-mentioned parameters decreased at 15℃ and 135℃ and this reduction at 35℃ was strong. Doubling time （DT） varied significantly with temperature. The shortest doubling time was obtained at 25℃. Mean generation time （T） decreased significantly with increasing temperature between 15℃ and 35℃. Percentage of immature ages in the stable age distribution was more than 95% at all temperatures. Female longevity was greater than male at all temperatures. Liriomyza sativae lived for a long time at 15℃, whereas at 35℃ had lower survival rates. The effect of temperature on reproduction, especially the intrinsic rate of increase of L. sativae would be useful for predicting its longterm population fluctuation over several generations.     

Effect of Incubation Temperature on the Somatic Development of the Snail-Eating Turtle Malayemys macrocephala

The rising average global temperature can lead to changes both in the physical and biological environments and affect the survival of organisms. Freshwater turtles are considered to be susceptible species since their development is dependent on incubation temperature. In Thailand, although several species of freshwater turtle are present, the extent of their susceptibility to temperature change is unknown due to the lack of information on their developmental patterns. This research, therefore, is aimed at examining the effects of temperature on somatic development in Malayemys macrocephala, a native species and the most common freshwater turtle in Thailand. Turtle eggs were collected from rice fields in the central part of Thailand during December 2011 to February 2012 inclusive. Eggs （237-238 per condition） were incubated in microprocessor-controlled incubators at three different temperatures （26 ℃, 29℃ and 32℃） with a relative humidity in excess of 80%. Each week, until the remaining eggs hatched, eggs were randomly selected, removed and dissected to reveal the developing embryo to screen for developmental stage and any abnormalities. The incubation period （lay to hatch） was not significantly different among the three temperatures （115 ±11.3 d, 115 ±20.3 d and 109±17.8 d, respectively）, but the growth patterns, as indicated by the stages of development and carapace lengths, were significantly different. At a high temperature （32℃）, turtle embryos showed a significantly faster growth rate than at the intermediate and low temperatures （29 ℃and 26 ℃）, but had a significantly （over 3.3-fold） higher incidence of developmental abnormalities （especially deformed bodies） than at the lower temperatures. Overall, the results indicate that incubation temperature is an important variable affecting the somatic development of this tropical freshwater turtle species, whilst abnormalities in the embryonic body may be a sensitive indicator of extreme thermal stress.     

Temperature-dependent development of Xyleborus fornicatus （Coleoptera： Scolytidae）, the shot-hole borer of tea in Sri Lanka： Implications for distribution and abundance

The effect of temperature on the rate of development of Xyleborus fornicatus （Eichh.） was determined by rearing individuals under a range of constant temperatures （15 - 32℃）. Rates of development changed in a linear fashion over a wide range of temperatures. Estimates of lower development thresholds were obtained for eggs （15.7±0.5℃）, larvae （15.8±0.8℃） and pupae （14.3±1.4℃） and the degree days （DD） for development were 70±4.4, 95±8.5 and 72±5.1 DD, respectively. Optimum temperature for development was around 30~C for all stages. Temperature fluctuation in cooler High Country areas （above 1400 m） with a mean temperature around 15℃ seems to be critical for the development of the pest, which may be responsible for the near absence of pest in those areas. Temperature fluctuations （18- 30℃） in the Mid Country region （600- 1200 m） favor the development of the pest compared to development under constant conditions. The altitudinal distribution of the shot-hole borer across tea growing areas in Sri Lanka is, therefore, mainly governed by temperature.     

Accumulation of cadmium and its effects on growth, development and hemolymph biochemical compositions in Boettcherisca peregrina larvae （Diptera： Sarcophagidae）

Newly emerged larvae of the fleshfly, Boettcherisca peregrina were exposed to two different CdCl2 concentrations of 100μg/g and 400 mg/g diet fresh weight （DFW）. They were administered in the diets until the end of larval stage. Cd-exposed larvae accumulated significant amounts of Cd and this accumulation increased with the exposure dose and time. The body weights were lightened and lengths of larvae were shortened considerably after Cd exposure, especially at the higher Cd concentration. The total larval duration was also extremely affected due to Cd exposure. The average duration was prolonged significantly by 14 h at the lower Cd concentration, while it was increased by 33.7 h over controls at the higher Cd concentration. A significant decrease in contents of either soluble proteins, total lipids or caloric values in the hemolymph occurred due to Cd exposure throughout the entire tested period but after 120 h of Cd exposure. In contrast, when exposed to Cd with its higher concentration, total sugar contents in the hemolymph were increased strikingly over the whole tested time, except after 96 h of Cd exposure, while they were not apparently altered except after 24 h of Cd exposure at the lower concentration. Thus, it is suggested that Cd exposure shows significant adverse impact on the growth and development, as well as metabolism, in larvae of this fleshfly, depending on its exposure time and dose.     

Comparison of Classical Models for Evaluating the Heat Requirements of Olive （Olea europeae L.） in Portugal

The aim of the present study was to compare the accuracy and reproducibility of six statistical models for the calculation of olive （Olea europeae L.） heat requirements to trigger the onset of flowering in three Portuguese regions： Reguengos de Monsaraz, Valenga do Douro, and Braga. Other alms were to ascertain the date on which the heat-accumulation period started and the threshold temperatures above which the development of reproductive structures starts in olives. The starting and peak dates for the regional O. europeae flowering season were estimated by monitoring airborne pollen from 1998 to 2004 using ＂Cour＂- type samplers. The threshold temperature values calculated for the three regions were very similar （9.0 ℃ for Valenca do Douro, 9.2 ℃ for Reguengos de Monsaraz, and 9.7 ℃ for Braga）. The accumulated daily mean temperature model had less interannual and inter-regional variation, showing best predictive results for 2004, with absolute differences between the observed and predicted dates of 4 d in Reguengos de Monsaraz and 2 d In Valenca do Douro and Braga for the onset of flowering date and of 2 d In Reguengos de Monsaraz, 7 d in Valenca do Douro, and 4 d in Braga for peak flowering dates. This model was the most accurate, reproducible, and operational to calculate heat requirements for olives to flower, with an average mean temperature accumulation of 1 446 ℃ In Reguengos, 1 642 ℃ in Valenga do Douro, and 1 703℃ In Braga to reach the onset of flowering. The best initial date for this accumulation was 1 January.     

Effect of Verticillium lecanfi on biological characteristics and life table of Serangium japonicum （Coleoptera： Coccinellidae）, a predator of whiteflies under laboratory conditions

Effects of entomopathogenic fungus Verticillium lecanii on biological characteristics and life table of Serangiumjaponicum, a predator of whiteflies against five different conidial concentrations （1 × 10^4, 1 × 10^5, 1 × 10^6, 1 × 10^7, and 1 × 10^8 conidia/mL） were studied under laboratory conditions. The developmental periods for all immature stages （from eggs, 1 st, 2nd, 3rd, 4th instar nymph and pupae up to emergence） among the treatments were significantly different when compared to that of control, and the longest development period was observed as treated with 1 × 10^8 spore/mL. However, no significant difference on the percent survival of all immature stages was observed among the treatments and control. Also, there were no significantly different effects of V. lecanii on mean generation time, intrinsic rate, the finite rate of increase and longevity of S. japonicum among the treatments and control.     

A Complete Embryonic Developmental Table of Microhyla fissipes(Amphibia,Anura, Microhylidae)

Access to embryonic developmental stages is essential basic work for understanding how organisms develop. In this study, seven egg clutches(range 209–564 eggs) of ornamented pygmy frog Microhyla fissipes(Amphibia, Anura, Microhylidae) were obtained from seven breeding pairs in laboratory. One egg clutch of them was observed for the embryonic development, and the staging table of normal development was constructed based on morphological and physiological characteristics. Forty-five developmental stages were defined for M. fissipes, and two major developmental periods were designated: 1) early embryonic development period(stages 1–28), from fertilization to operculum completion stage, lasted for 82.6 hours at water temperature(WT) 23–25℃; 2) larval development period(stages 29–45), from operculum completion to tail complete absorption stage, took 38 days at WT 22–26.5℃, showing that the embryos of this species develop rapidly. In addition, the tadpoles were transparent, which is similar to those in field. These characteristics suggest that M. fissipes would be a good model to study developmental biology, adaptive mechanisms from aquatic to terrestrial phases, environmental toxicology, and human disease.     

Effects of hunger and tannic acid on food intake and foraging behavior in Microtus fortis

The influence of hunger and plant secondary compounds on food selection and foraging behavior in Microtus fortis were measured in this study. The three selected kinds of tannic acid food were measured with the cafeteria method. The voles were first offered with food ad libitum for a period of 4 days. Food intake was recorded daily for calculation of average food intake by each vole. The calculated average food intake was multiplied by a hunger index (0, 25, 50, 75 or 100). Measurements were made over 4 consecutive nights for 2–4 feeding bouts per animal per night. The results indicated that hunger increased food intake, but had no significant effects on food selection. 0% tannic acid food was the most preferred food, and the intake of 6% tannic acid food was the least. Ingestion rate and bite size of voles increased with severity of hunger, but the feeding frequency was not significantly affected by hunger, and the time of feeding bout increased slowly. When the amount of food that voles have been offered is 25% more than that when they freely access to the food, the time of the feeding bout of hungry voles was significantly increased. These results suggested that voles increased their food intake mainly by increasing bite size when they were in hunger. The changes in foraging behavior indicated that herbivores increased their bite sizes and food intake rate to satisfy their nutritional demands rather than prolonged their foraging time and decreased the time for defending or reproductive activities to increase the amount of food intake.     

Change in flowering dates of Japanese Cherry Blossoms (P. yedoensis Mats.) on campus of Wuhan University and its relationship with variability of winter temperature

Change in first-flowering dates and its correlation with climatic factors was mainly analyzed, and several predicting models for the first-flowering dates were established based on the flowering dates of Japanese Cherry Blossoms (P. yedoensis Mats.) during 1947–2008 on campus of Wuhan University and the climatic data in the same period. The results show that: 1) in 1947–2000, the first-flowering dates advanced with 2.17 d per decade, with an overall trend of 11.72 d in the 54 years, the fading dates were postponed for only 1.83 d in the same period, and the florescence duration increased by 13.55 d; 2) the first-flowering dates have negative correlation with monthly average temperature from December to March. The increasing winter (from December to February) temperature is the main reason for the advancement of the first-flowering dates. Per 1°C increase in average temperature of February and wintertime makes the first-flowering dates advance by 1.66 d and 2.86 d, respectively; 3) some statistical models of the first-flowering dates were built up with average temperature of February and wintertime based on the data during 1947–2000, and they are detected independently during 2001–2008.     

Duration times of the immature stages of Cacopsylla pyri L. (Hom., Psyllidae), estimated under field conditions, and their relationship to ambient temperature

The duration of the immature stages of Cacopsylla pyri L. was studied under field conditions by artificially infesting pear branches on several dates during the year. The duration of the egg stage decreased from winter to summer, as the season progresses and temperature rises, and slightly increased in September. It ranged from 27.4 to 6.7 days. The same trend was observed in the duration of the first three larval stages (L₁₋₃) which ranged from 18.8 to 10.3 days. For eggs deposited during the period February–August the duration of the last two larval stages (L₄₋₅) ranged from 17.5 to 12.1 days. However, the duration of L₄₋₅ developed from eggs deposited in September and which give rise to winter-form adults were the longest observed. The rate of egg development was related to average ambient temperature with a highly significant linear relationship. This relationship indicates that the egg stage requires a constant number of 158.9 (SD = 5.0) of day-degrees above an average temperature of 2.31°C to complete development. The rate of development both of L₁₋₃ and L₄₋₅ were related to average ambient temperature with curvilinear relationships. These relationships indicate a proportional increase in the developmental rate as temperature rises between 10–22°C. At the higher average temperatures that occurred in the summer experiments (24–27°C) the acceleration of development of L₁₋₃ is reduced and the developmental rate of L₄₋₅ decreases. The developmental rates of L₄₋₅ developed from eggs deposited in September did not follow the established relationship with temperature and they were lower than those in the other periods of the year with the same average temperature.     

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.     

Effects of development, temperature and salinity on metabolism in eggs and yolk-sac larvae of milkfish, Chanos chanos (Forsskål)

Oxygen uptake rates and yolk-inclusive dry weiGhts were measured during the egg and yolk-sac larval stages of milkfish, Chanos chanos (Forsskal). Oxygen uptake by eggs and yolk-sac larvae was measured to assess the effects of four salinities (20,25,30,35 ppt) at 28°C. The effects of three temperatures (23,28,33°C) on oxygen uptake by yolk-sac larvae were determined at a salinity of 35 ppt. Dry weights were measured throughout embryonic development at 28°C and the yolk-sac stage at 23.28 and 33°C.
Oxygen uptake rates of eggs increased more than fivefold during embryogenesis (0.07±0.03 to 0.40 ± 03 μl O₂ egg ⁻¹ h ⁻¹;blastula to prehatch stage). Larval oxygen uptake did not change with age but was affected by rearing temperature (0.33 ± 0.08, 0.44 ± 0.07 and 0.63 ± 0.13 μl O₂ larva ⁻¹ h⁻¹ at 23, 28 and 33°C, respectively; Q₁₀= 1.93). Acute temperature changes from 28 to 33°C caused significant increases in oxygen uptake by embryos (Q ₁₀= 1.69–3.58) and yolk-sac larvae (Q ₁₀=2.55). Salinity did not affect metabolic rates.
Dry weight of eggs incubated at 28°C decreased 13% from fertilization to hatching. Incubation temperatures from 23–33°C did not affect dry weights at hatching. Rearing temperatures significantly affected the rate of larval yolk absorption (Q ₁₀= 2.25).     

Thermal tolerance of a northern population of striped bass Morone saxatilis

Thermal tolerance of age 0+ year Shubenacadie River (Nova Scotia, Canada) striped bass Morone saxatilis juveniles (mean ± s . e . fork length, L _F, 19·2 ± 0·2 cm) acclimated in fresh water to six temperatures from 5 to 30° C was measured by both the incipient lethal technique (72 h assay), and the critical thermal method ( C _m). The lower incipient lethal temperature ranged from 2·4 to 11·3° C, and the upper incipient lethal temperature ( I _U) from 24·4 to 33·9° C. The area of thermal tolerance was 618° C². In a separate experiment, the I _U of large age 2+ year fish (34·4 ± 0·5 cm L _F) was 1·2 and 0·6° C lower ( P < 0·01) than smaller age 1+ year fish (21·8 ± 0·5 cm L _F) at acclimation temperatures of 16 and 23° C. Using the C _m, loss of equilibrium occurred at 27·4–37·7° C, loss of righting response at 28·1–38·4° C and onset of spasms at 28·5–38·8° C, depending on acclimation temperature. The linear regression slopes for these three responses were statistically similar (0·41; P > 0·05), but the intercepts differed (25·3, 26·0 and 26·5° C; P < 0·01). The thermal tolerance of this northern population appears to be broader than southern populations.     

Effects of different incubation temperatures on the yolk‐feeding stage of Eupallasella percnurus(Pallas)

Embryos and yolk‐feeding larvae of lake minnow Eupallasella percnurus were reared at 13, 16, 19, 22 and 25° C with no access to external food. Time from egg activation to first embryonic movements, hatching, filling of swimbladder and final yolk resorption increased with decreasing temperature. At 13° C, c . 40% of larvae were unable to fill their swimbladder. The predicted lower temperature at which development and growth ceased (biological zero, t ₀) was the same for both processes, c . 7·5–10·5° C. There was no ontogenetic shift in the t ₀ value. Temperature coefficients for development ( Q _10dev.) ranged from 2 to 3 at 19–25° C, but were higher in hatched larvae at lower temperatures. Eggs of E. percnurus had a combination of small size, high hydration and low caloric value of fresh matter. Dry mass of larval tissue on yolk, percentage of dry matter in wet matter, and specific growth rate were maximized at 22 and 25° C. At 19–25° C, energy and matter contained in the initial eggs were converted to body tissue most efficiently. Temperatures from 22 to 25° C are considered optimal for E. percnurus embryos and yolk‐feeding larvae and are recommended for their indoor rearing.     

Influence of ambient and thoracic temperatures upon sexual behaviour of the gypsy moth, Lymantria dispar

ABSTRACT. In an ambient temperature ( T _a) range of 18–28°C, thoracic temperatures ( T _th) of individual male Lymantria dispar (L.), caught at flight in the field, ranged from 21 to 36.5°C, with a correlation coefficient of 0.63 between T _th and ambient temperature ( T _a). Ambient temperature (and insolation) altered the insect's body temperature and the probabilities, latencies, and durations of preflight responses to pheromone. In a wind tunnel at 16 and 20°C, quiescent males exposed to pheromone raised their T _th by sustained wing fanning from 17 and 21°C, respectively, to c. 24°C before takeoff. At 24 and 28°C ambient, T _th rose by takeoff to 28 and 31°C, respectively. The latencies of male wing fanning in response to pheromone decreased from 1.44 min at 16°C ambient, to 0.58 min at 20°C, to 0.26 min at 24°C, and to 0.16min at 28°C. The components of behaviour (antennal twitch, body jerk, step and wing tremor) that occurred between quiescence and wing fanning were more frequent at ambients of 16 and 20°C than at 24 and 28°C.     

Effect of temperature on life table parameters of Podisus nigrispinus (Het., Pentatomidae) fed with Alabama argillacea (Lep., Noctuidae) larvae

Abstract: The influence of temperature on life table parameters of Podisus nigrispinus (Dallas) (Het., Pentatomidae) fed with Alabama argillacea (Hübner) (Lep., Noctuidae) larvae was studied. This predator was kept at constant temperatures of 20, 23, 25, 28, 30 and 33±0.2°C, at relative humidity of 60±10% and photoperiod of L : D 14 : 10. Gross (GRR) and net ( R ₀) reproductive rates of P. nigrispinus ranged from 1.6 to 366.6 and from 0.02 to 189.5 females/female at temperatures of 33 and 28°C, respectively; generation time ( T  ) ranged from 33.3 (33°C) to 85.5 (20°C) days; doubling time ( D ) from 0.82 (33°C) to 17.8 (20°C) days; intrinsic rate of increase ( r _m ) from −0.13 (33°C) to 0.12 (28°C) per day; and the finite rate of increase ( λ ) from 0.88 (33°C) to 1.12 (28°C) females/female added to the population per day. The ideal age to release P. nigrispinus should be when this predator presents higher reproductive values (VR _x ); that is, its adults are about 7 days old, independent of prevailing temperature. Population growth of P. nigrispinus was affected by temperature with maximum numerical response between 28 and 30°C. The negative population growth shown at 33°C may not occur in natural conditions due to milder microclimate in the cotton agroecosystem and due to oscillations of temperature in the course of the day.     

Effect of long-term and rapid cold hardening on the cold torpor temperature of an aphid

Abstract.  The effect of long-term (seasonal) acclimation and rapid cold hardening is investigated on the cold torpor temperature ( CT _min) of adult grain aphids, Sitobion avenae, reared at 20 or 10 °C for more than 6 months before experimentation. Rapid cold hardening is induced by exposing aphids reared at 20 to 0 °C for 3 h and aphids reared at 10 to 0 °C for 30 min (acclimation regimes previously found to induce maximum rapid cold hardening). The effect of cooling aphids from the same rearing regimes from 10 to −10 °C at 1, 0.5 and 0.1 °C min⁻¹ is also investigated. In the 20 °C acclimated population, rapid cold hardening and cooling at 0.1 °C min⁻¹ both produce a significant decrease in CT _min from 1.5 ± 0.3 to –0.9 ± 0.3 and –1.3 ± 0.3 °C, respectively. Rapid cold hardening also results in a significant reduction in CT _min of the population reared at 10 °C from 0.8 ± 0.1 to –0.9 ± 0.2 °C. However, none of the cooling regimes tested reduces the CT _min of the winter-acclimated (10 °C) population. The present study demonstrates that rapid cold-hardening induced during the cooling phase of natural diurnal temperature cycles could lower the movement threshold of S. avenae , allowing insects to move and continue feeding at lower temperatures than would otherwise be possible.     

THE EFFECT OF TEMPERATURE ON EGGS AND IMMATURE STAGES OF CULEX ANNULIROSTRIS SKUSE (DIPTERA: CULICIDAE)

Abstract
No immature stages of Culex annulirostris were found during field sampling in 1979–1980 when the average water temperature was < 17 °C; they reappeared when the average water temperature was 19 °C and reached the peak density (mean 107 immatures/cylinder) at 26.5 °C.
The effect of 6 temperatures (15–40°C) on egg hatching, development and survival of the immature stages of Cx annulirostris in the laboratory showed that at 15 and 40°C, eggs failed to hatch and larvae died in the first instars. The optimum temperatures for egg hatching and the survival of immature stages were 25 and 30°C. At these temperatures, 85 and 82% respectively of egg rafts hatched, the mean number of larvae per raft was 258 ± 9.8 and 260 ± 11.4 with immature survival of 83.5 and 79.0% respectively. Mean time to hatch at 20–35°C ranged from 1.2 d (35°C) to 2.9 d (20 °C). Developmental times from first instar to adult ranged from 7.1 d (35 °C) to 25.2 d (20 °C). The threshold for development of the immatures was 15.6 ± 2.5°C and the thermal constant was 142.9 ± 26.5 day—degrees (incubation temperatures 20–35°C). At less suitable temperatures of 20 and 35 °C, hatching (57.5 and 45%), number larvae per raft (mean 139.8 ± 9.8 and 102.6 ± 14.2) and survival were low.     

EFFECTS OF TEMPERATURE ON CERTAIN POPULATION PARAMETERS OF LIRIOMYZA SATIVAE BLAN-CHARD (DIPTERA: AGROMYZIDAE)

Abstract  Effects of temperature on population parameters and the intrinsic rate of natural increase of the leafminer, Liriomyza sativae Blanchard, were studied at constant temperatures, 15, 20, 25, 30 and 3593 80% RH and a photoperiod of 12 :12 (L:D) in the laboratory with Phaseolus vulgaris as the host plant. Developmental time of the immature stage decreased from 38 d at 15C to lld at 35⁹3 Regression equations relating temperature ( t ) to development rates ( y ) for egg, larval and pupal stages, were y = 1.7862t - 13.841, y = 1.162 t - 4.946 and y = 0.634 t - 5.146, respectively. Longevity of female adult decreased from 20 d at 15°C to 9 d with temperature up to 35C The most favorable temperature range for reproduction was 20°C - 30^oC in which the fecundity ranged from 158 to 282 eggs per female. The lowest total mortality was 9% at 25^oC and the highest was 49% at 35 93 High intrinsic rate of natural increase ( r_m ) was 0.27 and high net reproductive rate ( R₀ ) was 116.8 at temperature range between 25 t and 30 t indicating that this range was optimal for population growth and that population density might increase 117 times per generation under this temperature condition. Mean generation time (T) and time for population to double (t) decreased as temperature increased, showing a negative linear trend with temperature. The relationship between finite rate of increase (A) and temperature, however, was a positive linear regression.