Effects of temperature on two Mediterranean population of Dinophilus gyrociliatus (Polychaeta: Dinophilidae): II. Effects on demographic parameters

The effects of temperature on demographic characteristics of two populations from Ravenna and Genoa of the polychaete Dinophilus gyrociliatus were investigated. Temperature affects age-specific survival and fecundity and all the demographic parameters often to a different degree in the two populations. Individuals from Ravenna survive longer than those from Genoa. The most evident differences in the age-specific fecundity curves of the experimental groups are related to age at maturity and the duration of the reproductive period that are in inverse proportion to temperature. In both populations of D. gyrociliatus, the maximum daily fecundity is observed at intermediate temperatures. In all cases, the Genoa females mature earlier, attain their maximum fecundity more quickly and have a shorter reproductive period than their Ravenna counterparts.Age at maturity, fecundity during the first reproductive events and juvenile survival are by far the most important characteristics in determining the fitness of the two populations at the tested temperatures. Even though the greatest net growth rates and highest expectation of life were recorded at 12 °C in the Ravenna population, the delay in the attainment of sexual maturity means that, at this temperature, the population growth rate is lowest. The higher juvenile survivorship and the greater fecundity observed at 24 °C is counter-balanced by the early attainment of sexual maturity induced at 30 °C. The comparison of the population growth rate calculated in laboratory with field data suggests that temperature is one of the main environmental parameters determining the fitness of D. gyrociliatus.     

Effects of temperature, salinity, and air exposure on development of the estuarine pulmonate gastropod Amphibola crenata

The primitive pulmonate snail Amphibola crenata embeds embryos within a smooth mud collar on exposed estuarine mudflats in New Zealand. Development through hatching of free-swimming veliger larvae was monitored at 15 salinity and temperature combinations covering the range of 2-30 ppt salinity and 15-25 °C. The effect of exposure to air on developmental rate was also assessed. There were approximately 18,000 embryos in each egg collar. The total number of veligers released from standard-sized egg collar fragments varied with both temperature and salinity: embryonic survival was generally higher at 15 and 20 °C than at 25 °C; moreover, survival was generally highest at intermediate salinities, and greatly reduced at 2 ppt salinity regardless of temperature. Even at 2 ppt salinity, however, about one-third of embryos were able to develop successfully to hatching. Embryonic tolerance to low salinity was apparently a property of the embryos themselves, or of the surrounding egg capsules; there was no indication that the egg collars protected embryos from exposure to environmental stress. Mean hatching times ranged between 7 and 22 days, with reduced developmental rates both at lower temperature and lower salinity. At each salinity tested, developmental rate to hatching was similar at 20 and 25 °C. At 15 °C, time to hatching was approximately double that recorded at the two higher exposure temperatures. Exposing the egg collars to air for 6-9 h each day at 20 °C (20 ppt salinity) accelerated hatching by about 24 h, suggesting that developmental rate in this species is limited by the rates at which oxygen or wastes can diffuse into and from intact collars, respectively. Similarly, veligers from egg capsules that were artificially separated from egg collars at 20 °C developed faster than those within intact egg collars. The remarkable ability of embryos of A. crenata to hatch over such a wide range of temperatures and salinities, and to tolerate a considerable degree of exposure to air, explains the successful colonization of this species far up into New Zealand estuaries.     

Effects of temperature on survival and preimaginal development rates of Colorado potato beetle on potato and horse-nettle: potential role in host range expansion

The effect of temperature on the ability of Colorado potato beetles (Leptinotarsa decemlineata, Say) to use horse-nettle (Solanum carolinense L.) as a host plant was determined for larvae from colonies originating from two geographically separated populations, one adapted to horse-nettle (NC) and the other unadapted to horse-nettle (MA). Survival and developmental rate on horse-nettle and potato were measured for larvae from both colonies over a range of constant temperatures (12–30 °C) and one fluctuating temperature regime (22 °C to 30 °C). The ability of Colorado potato beetles to use horse-nettle as a larval host was strongly influenced by temperature, but the effects of temperature differed greatly between beetles from the two colonies. Survival of adapted larvae on horse-nettle was highest and comparable to that on potato at the constant 30 °C and the fluctuating temperature regime. Below 30 °C, survival of adapted larvae decreased drastically but some larvae survived at all temperatures except the lowest (12 °C). In contrast, survival of unadapted larvae to adult occurred only at 30 °C, and was low (10%). At lower temperatures, all larvae died. On potato, the effect of temperature was less dramatic, and consistent across colonies. At 12 °C, survival to adult was poor (ca. 10%), but at higher temperatures, survival increased sharply and larvae from both colonies survived equally well. On potato, small but statistically significant differences in developmental rates between beetle colonies were detected at the constant but not at the fluctuating temperature regimes. Also, the developmental day degree requirements (DD) and the low temperature development threshold (T0) values for the various developmental stages did not differ between colonies on potato. On horse-nettle, development times for both colonies were always significantly longer and DD requirements were greater than on potato. At 30 °C, the only constant temperature at which larvae from the unadapted colony completed development, the development rate to adult emergence was similar to that of beetles from the adapted colony. Differences between colonies in performance on horse-nettle were not a result of host-independent, genetically based differences in the thermal requirements of the two populations. Our findings are consistent with the hypothesis that adaptation to horse-nettle by Colorado potato beetle may be facilitated by a genotype × environment interaction involving temperature. These findings have important implications for host plant utilization, host range expansion and selection of pest biotypes adapted to plant resistance traits used in crop protection.     

Effects of gestation temperature on offspring sex and maternal reproduction in a viviparous lizard (Eremias multiocellata) living at high altitude

Temperature-dependent sex determination (TSD) is well studied in many species of reptiles, but little is known on how geographic distribution and altitude affect the sex ratio. In the present study, we focused on a population of a viviparous lizard with TSD (Eremias multiocellata) that lives at high altitudes (≈2900 m) in Tianzhu, Gansu province, China. Gestation temperature had a notable effect on the offspring sex ratio, gestation period, and the mother's body mass. The mothers produced female biased offspring at 25 °C but male biased offspring at 35 °C. All female lizards lost weight during pregnancy, and the least loss of the body mass was observed at 31 °C. The gestation period increased in a non-linear fashion as ambient temperature was reduced. Average litter size was elevated with an increase of gestation temperatures, reached a maximum at 31 °C, and then declined at 35 °C. Compared with a previous study on a Minqin population which lives at a lower altitude (≈1400 m) and warmer climate, the present study obtained a less skewed sex ratio of offspring in the Tianzhu population. Geographic variations also affected offspring morphology between the two populations; females collected from Tianzhu produced larger litters but with a smaller body weight of offspring. These differences may be caused by the adaptive response to the cool climatic and high-altitude environmental conditions.     

Effect of age and body size on selected temperature by juvenile wood turtles (Glyptemys insculpta)

In an aquatic thermal gradient of 15–30 °C, 3-, 6-, and 12-month-old juvenile wood turtles (Glyptemys insculpta) acclimated to 20 °C selected the warmest temperature available (30 °C) and avoided the coldest temperatures available (15 and 18 °C). Mean selection of chambers differed between control and gradient tests across all temperatures except 27 °C. Turtles of all age classes relocated between chambers less often when the gradient was present than during control tests. Six- and 12-month-old turtles selected 30 °C more frequently, and selected colder temperatures less frequently, than 3-month-old turtles, suggesting that the ability to select preferred temperatures is better developed in older hatchlings.     

Effect of temperature, salinity and delayed attachment on development of the solitary ascidian Styela plicata (Lesueur)

The solitary ascidian Styela plicata (Lesueur) is a common member of epibenthic marine communities in Hong Kong, where seawater experiences extensive seasonal changes in temperature (18-30 °C) and salinity (22-34‰). In this investigation, the relative sensitivity of different developmental stages (i.e., duration of embryonic development, larval metamorphosis and post-larval growth) to various temperature (18, 22, 26 and 30 °C) and salinity (22‰, 26‰, 30‰ and 34‰) combinations is reported. Fertilized eggs did not develop at lower salinities (22‰ and 26‰). At higher salinities (30‰ and 34‰), the duration of embryonic development increased with decreasing temperature (18 °C: 11.5±0.3 h; 30 °C: 8.5±0.3 h). More than 50% of larvae spontaneously attached and metamorphosed at all the levels of temperature and salinity tested. At higher temperatures (22, 26 and 30 °C) and salinities (30‰ and 34‰), functional siphon developed in about 72 h after hatching, whereas at low temperature (18 °C), siphon developed only in <30% of individuals in about 90 h. However, none of the metamorphosed larvae developed subsequently at low salinity (22‰). When forced to swim (or delayed attachment), larvae lost about 0.27 mJ after 48 h (about 22% of the stored energy). Such a drop in energy reserves, however, was not strong enough to cause a significant impact on post-larval growth. This study suggests that temperature and salinity reductions due to seasonal monsoon may have significant effect on the embryo and post-larval growth of S. plicata in Hong Kong.     

Cold tolerance of the harlequin ladybird Harmonia axyridis in Europe

As an essential aspect of its invasive character in Europe, this study examined the cold hardiness of the harlequin ladybird Harmonia axyridis. This was done for field-collected populations in Belgium overwintering either in an unheated indoor or an outdoor hibernaculum. The supercooling point, lower lethal temperature and lower lethal time at 0 and −5 °C were determined. Possible seasonal changes were taken into account by monitoring the populations during each winter month. The supercooling point and lower lethal temperature remained relatively constant for the overwintering populations in the outdoor hibernaculum, ranging from −17.5 to −16.5 °C and −17.1 to −16.3 °C, respectively. In contrast, the supercooling point and lower lethal temperature of the population overwintering indoors clearly increased as the winter progressed, from −18.5 to −13.2 °C and −16.7 to −14.1 °C, respectively. A proportion of the individuals overwintering indoors could thus encounter problems surviving the winter due to premature activation at times when food is not available. The lower lethal time of field populations at 0 and −5 °C varied from 18 to 24 weeks and from 12 to 22 weeks, respectively. Morph type and sex had no influence on the cold hardiness of the overwintering adults. In addition, all cold tolerance parameters differed greatly between the laboratory population and field populations, implying that cold tolerance research based solely on laboratory populations may not be representative of field situations. We conclude from this study that the strong cold hardiness of H. axyridis in Europe may enable the species to establish in large parts of the continent.     

In vitro effects of temperature and salinity on fatty acid synthesis in the oyster protozoan parasite Perkinsus marinus

The effects of temperature and salinity on fatty acid synthetic activities in the oyster protozoan parasite, Perkinsus marinus, were tested in vitro at 10, 18 and 28 °C in a salinity of 28 psu and 14, 20 and 28 psu at a temperature of 28 °C using ¹³C sodium acetate as a substrate. Salinity treatments exhibited few treatment effects, but temperature significantly affected cell proliferation, fatty acid content and fatty acid synthesis rates. Fatty acid synthesis rates increased approximately two-fold for every 10 °C increase in temperature; however, the predominant fatty acid synthesized differed between treatments. At 10 °C, the synthesis rate for 18:1(n−9) was not significantly different from the 18 °C treatment and weight percent of 18:1(n−9) was higher at 10 than 18 and 28 °C. In contrast, the synthesis rate for 20:4(n−6) was over five times lower at 10 than at 18 and 28 °C, and the percent fatty acid content of 20:4(n−6) was over two-fold lower at 10 than at 18 and 28 °C. Results suggest that further elongation and desaturation of 18:1(n−9) to 20 carbon polyunsaturated fatty acids may be inhibited at low temperatures. These findings may be relevant to field observations that disease progression and virulence of this parasite are correlated to high water temperatures.     

Effects of temperature on the spores of thermophilic actinomycetes

The effects of temperature on the germination properties of spores of thermophilic actinomycetes were examined. Temperatures above and below the growth temperature of 55° C were found to produce marked changes in the germination properties of spores. High temperatures caused reductions in the germinative activities of spores. However, heated spore populations regained original germinative activities after maintaining them for suitable periods of time at 25°C. Recovery from the effects of heat on spore germination was also observed at 4°C, but at a much slower rate compared with 25°C. Spores of two strains of thermophilic actinomycetes, grown and prepared at 55°C, failed to germinate. Storage of dormant (nonactivated) spore populations at different temperatures demonstrated a low temperature requirement for the activation of these spores; while little or no activation occurred at 55°C, rapid activation took place at 25°C. Heating the spores at 80°C for 30 min slightly delayed the activation (rates) of spores at 25°C. The requirement of low temperature for spore activation was strain dependent and was influenced by the composition of the germination medium.     

Upper thermal thresholds of shallow vs. deep populations of the precious Mediterranean red coral Corallium rubrum (L.): Assessing the potential effects of warming in the NW Mediterranean

Recent mortality outbreaks in marine ecosystems have been linked to elevated seawater temperatures associated with global climate change. Acquisition of thermotolerance data is essential, not only to determine the role of temperature in mortality outbreaks, but also to predict consequences of global warming. In the NW Mediterranean region, elevated seawater temperatures during the summer periods of 1999 and 2003 caused mass mortality of the Mediterranean red coral, Corallium rubum (L. 1758). Experiments testing the upper thermal limits of this species were carried out in aquaria using samples collected from populations from 11 to 40 m depth in the Marseilles region (NW Mediterranean, France). Samples were subjected to temperature treatments between 18 and 30 °C with an exposure time of 5 and 25 days. Three biological response variables were used to evaluate effects of the treatments: coenenchyme necrosis, polyp activity and calcification rates (⁴⁵Ca incorporation in calcareous skeleton). The results showed that exposure to 24 °C for 24 days caused a beginning of mortality only for the deep population, and to 25 °C for between 9 and 14 days caused mass mortality of both sample groups. The response variable results indicate that samples from the shallow population had greater thermotolerance of elevated seawater temperatures than the deep samples. The shallow samples showed greater polyp activity and higher calcification rate with a delayed necrosis response than the deep samples. These initial thermotolerance results combined with both hydrographic models and seawater temperature monitoring are the first step towards developing predictive tools for anticipating future effects of climate change in the red coral populations.     

Effects of temperature and salinity on larval development ofElminius modestus (Crustacea,Cirripedia) from Helgoland (North Sea) and New Zealand

Larvae ofElminius modestus (Darwin) from four different populations (Portobello, Leigh, Doubtless Bay [New Zealand] and Helgoland [North Sea]) were reared at different salinity and temperature combinations. The larvae ofE. modestus from Helgoland developed successfully at a wide range of temperature (6° to 24 °C) and salinity (20 to 50 S). Mortality was highest at 10 S; only at 12° and 18 °C did a small percentage develop to the cypris. The larvae from New Zealand were reared at a temperature range of 12°–24 °C at 20, 30 and 40 S; mortality increased in all populations at all salinities with decreasing temperature and was extremely high at 12 °C and 40 S. The temperature influence on larval duration could be described in all cases by a power function. No significant differences in temperature influences on developmental times between the tested salinities were found, except for the Portobello population at 20 S. Significant differences were found in the temperature influence on larval development between the populations from Helgoland and the North Island of New Zealand (Leigh, Doubtless Bay). No differences were found between the Helgoland and Portobello population. The pooled data for the temperature influence on the larval development of the three tested New Zealand populations at 20, 30 and 40 S and the pooled Helgoland data at 20, 30 and 40 S show highly significant differences.Larval size (stage VI) was influenced by experimental conditions. The larvae grew bigger at low temperatures and attained their maximum size at 30 S (Helgoland). There was a strong reduction in larval size at temperatures from 18° to 24 °C. The larvae of the New Zealand populations were smaller than those from Helgoland. The greatest difference in size existed between the larvae from Portobello and Helgoland.     

Effects of incubation temperature on growth and development of embryos ofAlligator mississippiensis

Summary Eggs ofAlligator mississippiensis were incubated at 30 °C and 33 °C throughout incubation up to hatching. Every four days several eggs were opened and the albumen, yolk and extra-embryonic fluids removed and weighed. The embryo was removed and fixed prior to being staged, weighted and measured for various morphometric criteria. Development at 33 °C was accelerated compared with 30 °C in terms of yolk and albumen utilization and embryo growth. Significant losses in yolk mass did not occur until stage 22 at 33 °C but occurred at stage 18 at 30 °C. Different patterns in growth were observed in embryos at the two temperatures at similar morphological stages: between stages 18 and 22 embryos at 33 °C were smaller (in mass and length) compared with embryos at 30 °C despite being morphologically similar. The differences in growth and physiology between embryos at 30 °C (females) and 33 °C (males) were dependent on incubation temperature but not sex. Incubation at 33 °C accelerated both growth and development inAlligator; initially morphogenesis was accelerated by the higher temperature but later, growth rate was accelerated.     

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.     

Predation activity of two winter-active spiders (Araneae: Anyphaenidae,Philodromidae)

Anyphaena accentuata and Philodromus spp. are cold adapted and winter-active spider species. Their predation activity was investigated at constant temperatures between –4 and 30 °C. The lower temperature threshold for Anyphaena was –3.7 °C, while that of Philodromus was –1.2 °C. At 1 °C the latency to capture and prey consumption was significantly shorter in Anyphaena than in Philodromus. The capture rate increased with temperature and was maximal at 15 °C in Anyphaena and at 30 °C in Philodromus. At 30 °C, the latency to the capture was significantly shorter in Philodromus than in Anyphaena whose mortality significantly increased.     

Effects of alternating temperatures onAcarus siro L. (Acari: Acaridae)

Fecundity, longevity and survival to adulthood ofAcarus siro (L.) at constant and alternating temperatures were compared. Both fecundity and longevity were affected by alternating temperatures but the effect of the frequency of alternations was not significant. Significantly higher fecundity and longer life spans were recorded at constant temperatures of 14 and 21°C than at 28°C or at alternating temperature regimes. Alternating temperature regimes in comparison to constant regimes did not significantly change the number of males and females surviving to adulthood or the sex ratio. However, the lowest number of adults surviving was recorded when temperatures were changed every 12 h and the highest at a constant temperature of 14°C.     

Embryonic development rate and hatchling phenotypes in the Chinese three-keeled pond turtle (Chinemys reevesii): The influence of fluctuating temperature versus constant temperature

Although the effects of constant temperatures on hatchling traits have been extensively studied in reptiles, the effects of fluctuating temperatures remain poorly understood. Eggs of the Chinese three-keeled pond turtle (Chinemys reevesii) were incubated at a constant temperatures (28 °C) and two fluctuating temperatures (28±3 °C and 28±6 °C) to test for the influence of thermal environment on incubation duration, hatchling traits, and post-hatching growth. Incubation duration was shorter at constant temperature than at fluctuating temperatures. The sex ratio of hatchlings varied among temperature treatments, with more females from 28±6 °C than from 28 °C. The size and mass were greater for hatchlings from a constant temperature than from fluctuating ones, but this difference in body size disappeared when the hatchlings were 3 months old. In addition, the swimming ability, survival, and growth of hatchlings from fluctuating temperatures did not differ from those of hatchlings from constant temperature, when they were kept at an artificial environment without food scarcity or predation. Therefore, the thermal environments with various temperature fluctuations used in this study do not significantly affect fitness-related hatchling traits in this species.     

Phenotypic variation in hatchling Chinese ratsnakes (Zaocys dhumnades) from eggs incubated at constant temperatures

We incubated eggs of the Chinese ratsnake Zaocys dhumnades at four constant temperatures (24, 27, 30 and 30 °C) to examine the effects of incubation temperature on hatching success and hatchling phenotypes. Incubation length increased nonlinearly as temperature decreased, with the mean incubation length being 76.7 d at 24 °C, 57.4 d at 27 °C, 47.3 d at 30 °C, and 44.1 d at 33 °C. Hatching successes were lower at the two extreme temperatures (69% at 24 °C, and 44% at 33 °C) than at the other two moderate temperatures (96% at 27 °C, and 93% at 30 °C). Incubation temperature affected nearly all hatchling traits examined in this study. Incubation of Z. dhumnades eggs at 33 °C resulted in production of smaller hatchlings that characteristically had less-developed carcasses but contained more unutilized yolks. Hatchlings from eggs incubated at 27 and 30 °C did not differ in any examined traits. Taking the rate of embryonic development, hatching success and hatchling phenotypes into account, we conclude that the temperature range optimal for incubation of Z. dhumnades eggs is narrower than the range of 24−33 °C but should be wider than the range of 27−30 °C.     

Effects of temperature on the establishment potential of the predatory mite Amblyseius californicus McGregor (Acari: Phytoseiidae) in the UK

Amblyseius californicus was introduced into the UK in the early 1990s as a biocontrol agent against glasshouse red spider mite Tetranychus urticae. This study investigated the effects of temperature on the establishment potential of A. californicus in the UK in the light of recent reports of their successful overwintering outside of glasshouse environments. The developmental thresholds were 9.9 and 8.6 °C respectively using simple and weighted linear regression. Using the day-degree requirement per generation calculated by weighted regression (143 day-degrees) in combination with climate data, it was estimated that up to seven generations would be possible annually outdoors in the UK. Non-diapausing adult females froze at −22 °C, with 100% mortality after reaching their freezing temperature. Up to 90% of mites died before freezing after short exposures to low temperatures. Significant acclimation responses occurred; 90% of acclimated individuals survived 26 days exposure at 0 °C and 11 days at −5 °C (acclimated mites were reared at 19 °C, 6L:18D followed by 1 week at 10 °C, 12L:12D). Non-diapausing adult females survived over 3 months outdoors in winter under sheltered conditions and oviposition was observed. The experimental protocol used in this study is discussed as a pre-release screen for the establishment potential of other Amblyseius species, and similar non-native biocontrol agents.     

Effects of salinity, temperature and pH on the survival of the nemertean Procephalothrix simulus Iwata, 1952

The salinity, temperature and pH tolerance of Procephalothrix simulus Iwata, 1952, were experimentally studied. In hypo-media, the nemerteans could survive 96 h in 3.3‰ solution at 10 °C (median lethal salinity [LS₅₀] was not determined at this temperature), and 96 h LS₅₀ were 7.3‰ and 13.5‰ at 20 °C and 30 °C, respectively. In hyper-media, 96 h LS₅₀ values were 53.9‰, 47.1‰ and 41.4‰ at 10 °C, 20 °C and 30 °C, respectively. The trend of body weight changes in diluted media indicated that this nemertean is a volume regulator. During a 96-h exposure in media at 0 °C, worms were thanatoid but could recover if the temperature was gradually elevated to 20 °C. In thermal tolerance experiments, the nemertean survived 96 h in seawater of 30 °C, and worms suffered high mortalities when the temperature exceeded 32 °C. Present results suggest that the interaction of temperature and salinity on the lethal effects on P. simulus is significant (P < 0.05). Elevated temperature (range 10-30 °C) decreased the worm's solute tolerance, and elevated salinity (range 18-38‰) decreased the worm's thermal tolerance. The survival pH level for this nemertean ranged from 5.00 to 9.20.     

Effect of temperature on reproductive parameters and longevity of <Emphasis Type="Italic">Tyrophagus putrescentiae</Emphasis> (Acari: Acaridae)

The effect of temperature on reproductive parameters and longevity of the mold mite, Tyrophagus putrescentiae (Schrank) was examined at seven constant temperatures, ranging from 10 to 34 °C, and a relative humidity of 90±5%. Preoviposition period and fecundity were adversely affected by extreme temperatures and the oviposition period increased as temperature was reduced. Different patterns were observed for longevity data for males and females, with greater longevities for males at intermediate temperatures and more similar values for both sexes at extreme temperatures. Polynomial and non-linear models provided a good fit of the relationship of reproductive and longevity parameters with temperature. The effect of temperature on the intrinsic rate of increase of T. putrescentiae populations was established by the non-linear Lactin model. The optimum temperature for development was obtained at 30 °C. At this temperature, the population doubling time is 1.75 days. The lower and upper thresholds for T. putrescentiae populations were established at 10.4 and 34.8 °C, respectively. Altogether, these data provide basic information to develop sound physical control strategies of the mold mite.