How heatwaves affect short-term emergency hospital admissions due to bacterial foodborne diseases.

The coming decades are likely to see of extreme weather events becoming more intense and frequent across Europe as a whole and around the Mediterranean in particular. The reproduction rate of some microorganisms, including the bacteria that cause foodborne diseases, will also be affected by these events. The aim of this study was thus to ascertain whether there might be a statistically significant relationship between emergency hospital admissions due to the principal bacterial foodborne diseases (BFDs) and the various meteorological variables, including heatwaves. We conducted a time-series study, with daily observations of both the dependent variable (emergency hospital admissions due to BFDs) and the independent variables (meteorological variables and control variables of chemical air pollution) across the period 2013-2018 in the Madrid Region (Spain), using Generalised Linear Models with Poisson regression, in which control and lag variables were included for the purpose of fitting the models. We calculated the threshold value of the maximum daily temperature above which such admissions increased statistically significantly, analysed data for the whole year and for the summer months alone, and estimated the relative and attributable risks. The estimated attributable risk was 3.6 % for every one-degree rise in the maximum daily temperature above 12 °C throughout the year, and 12.21 % for every one degree rise in temperature above the threshold heatwave definition temperature (34 °C) in summer. Furthermore, different meteorological variables displayed a statistically significant association. Whereas hours of sunlight and mean wind speed proved significant in the analyses of both the whole year and summer, the variables "rain" and "relative humidity", only showed a significant relationship in the analysis for the whole year. High ambient temperature is a risk factor that favours the increase in emergency hospitalisations attributable to the principal BFDs, with a greater impact being observed on days coinciding with heatwave periods. The results yielded by this study could serve as a basis for implementing BFD prevention strategies, especially on heatwave days.

Studies on the embryonic development and larval infection potential of the stomach bot flies, Gasterophilus pecorum.

Endangered Przewalski's horses have faced severe infections from Gasterophilus pecorum (Diptera, Gastrophilidae) in Xinjiang's Kalamaili Nature Reserve (KNR). This study examines G. pecorum's development and infection patterns in embryonic and larval stages, crucial for understanding horse botfly disease in desert grasslands. For the incubation of G. pecorum fertilized eggs, we established the six distinct temperature gradients: 16 °C, 20 °C, 24 °C, 28 °C, 30 °C, and 32 °C. Using the least squares method, we calculated the correlation between the developmental threshold temperature of the eggs and their cumulative effective temperature. Furthermore, we meticulously recorded the survival duration of the larvae across a spectrum of temperature gradients (-20 °C, -10 °C, 4 °C, 10 °C, 20 °C, and 30 °C) and under varying conditions (dark and light). This method allows us to analyze and interpret the impact of these environmental factors on larval survival durations. 1) The formula for predicting the embryonic development period of G. pecorum was N = (182.7 ± 12.03)/[T-(3.191 ± 1.48)], where the developmental threshold temperature was 3.191 ± 1.48 °C, and the effective accumulated temperature was 182.7 ± 12.03 d°C 2) The model describing the relationship between the embryonic development rate and temperature was: y = 0.0001x2+0.0007x+0.0378, demonstrating a positive correlation between the development rate and temperature (R-sq = 0.989, p < 0.001). 3) Larvae in the dark group exhibited a longer survival time, with the longest being 9 months at 4 °C. The adaptation of G. pecorum's embryonic development to cold temperature, combined with the extended survival period of larvae in the egg state, significantly increases the infection potential of G. pecorum in colder climates. This discovery offers essential insights into the predominance of G. pecorum in the KNR region and provides a crucial biological basis for the prevention of myiasis and the conservation of vulnerable species, such as Przewalski's horses.

Development of a degree-day model to predict the growth of Anopheles stephensi (Diptera: Culicidae): implication for vector control management.

Anopheles stephensi is an efficient vector of malaria parasites in Iran. Despite its importance in malaria transmission, there is a scarcity of accurate predictive models of its rates of development at different temperatures. A laboratory colony of An. stephensi, collected from Bandar Abbas County, southern Iran, was established, and all its developmental stages were maintained in temperature-controlled incubators so that the water temperature set at 5, 8, 10, 12.5, 14, 28, 38, 39.5, 42, and 45(±0.2) °C for different treatments until subsequent adult emergence. The Lower and Upper Developmental Temperatures (LDT and UDT) and the growth degree-day (GDD) were calculated for each development stage. A 12-mo population dynamics survey of the larvae and adults of An. stephensi was performed in 3 malaria-endemic villages (Geno, Hormoodar, and Sarkhoon) of Bandar Abbas County, and the obtained data were matched with the constructed GDD model. Based on the field meteorological and dynamics data, the model was verified in the field and used to determine the appropriate date to start spraying. The LDT was determined to be 8.19, 9.74, 8.42, 5.6, 13.57, and 10.03 °C for egg hatching, first, second, and third ecdysis, pupation, and eclosion events, respectively. The UDT was 38 °C for all developmental stages. The thermal requirement for the development of all immature stages of An stephensi was determined to be 187.7 (±56.3) GDD above the LDT. Therefore, the appropriate date to start residual spraying is when the region's GDD reaches 187.7 (±56.3). Given the climatic conditions in Bandar Abbas County, it is expected that the first activity peak of adult An. stephensi would be in March. Field observations showed that An. stephensi activity starts in February and peaks in March. The GDD model can provide a good estimate for peak An. stephensi activity and indicate the optimal deployment time of residual spraying operations against the multiplication and development of malaria parasites inside the vector.

Precipitation regulates the responses of xylem phenology of two dominant tree species to temperature in arid and semi-arid forest of the southern Altai Mountains.

Arid and semi-arid forests are important carbon sinks, with implications for the global carbon balance. However, the impacts of climate warming on the growth of arid and semi-arid forest tree species and ecosystem carbon sink dynamics remain uncertain because the effects of the complex interactions between precipitation and temperature on xylem phenology are not clearly understood. Here, we monitored xylem formation over two years in two dominant tree species (Siberian larch, Larix sibirica Ledeb.; Siberian spruce, Picea obovata Ledeb.) along the arid and semi-arid southern Altai Mountains of Central Asia. We determined that temperature interaction with precipitation plays a key role in regulating xylem phenology of these two species, with differences between species. Under rising mean annual temperatures, the growth of L. sibirica advanced as the onset of xylem formation was not limited by early season water availability. However, the earlier cessation of cell enlargement, likely due to legacy effects, compensated for such advancement. In contrast, water stress constrained the advancement of xylem formation under rising temperatures in P. obovata. Nevertheless, water stress was seemingly relieved later in the growing season and consequently did not lead to the earlier cessation of xylem formation. Our results demonstrate that precipitation drives species-specific response to rising temperatures and thus is a key driver of growing season length and carbon sink dynamics in arid and semi-arid forests under climate warming. Integrating the effects of temperature and precipitation on xylem phenology in climate models may improve estimates of climate-carbon feedback in arid and semi-arid forests under future warming scenarios.

Developmental dynamics and survival characteristics of the common horse bot flies (Diptera, Gasterophilidae, Gasterophilus) in desert steppe.

The genus Gasterophilus (Diptera, Gastrophilidae) is an obligate parasite of the equine family that causes widespread myiasis in desert steppe. Based on four common naturally excreted Gasterophilus larvae collected systematically in the Karamaili Ungulate Nature Reserve from March to September 2021, this paper studies the population dynamics and ontogenetic laws of horse flies, and discuss the coexistence pattern and population dynamics prediction of horse flies. The results showed that the Gasterophilus larvae had obvious concentrated development period, and the time of population peaks was different, the earliest was G. nigricornis (late March), followed by G. pecorum-Ⅰ (mid-April), G. nasalis (late April), G. intestinalis (early May), G. pecorum-Ⅱ (mid-August). The order of development threshold temperature "Cnigricornis < Cpecorum-Ⅰ ≤ Cpecorum-Ⅱ < Cnasalis < Cintestinalis" is consistent with the peak order of different larval populations. The life history survival rate (L) was as follows: Lnigricornis (83.97%) ≥ Lintestinalis (81.25%) > Lnasalis (72.42%) ≥ Lpecorum-Ⅱ (71.65%) > Lpecorum-Ⅰ (39.23%). This study combined indoor experiments and field surveys revealed the development of horse fly populations with different life strategies in desert grasslands. Based on the different development threshold temperatures of several horse flies, the staggered population dynamics of Gasterophilus form continuous infection stress on the host. In addition, G. pecorum exhibited a univoltine bimodal population distribution in this area and led to two high-intensity host infections, which is one of the important reasons why it has become the dominant species of myiasis in desert steppe.

Heat stress tolerance in peas (Pisum sativum L.): Current status and way forward.

In the era of climate change, the overall productivity of pea (Pisum sativum L.) is being threatened by several abiotic stresses including heat stress (HS). HS causes severe yield losses by adversely affecting several traits in peas. A reduction in pod yield has been reported from 11.1% to 17.5% when mean daily temperature increase from 1.4 to 2.2°C. High-temperature stress (30.5-33°C) especially during reproductive phase is known to drastically reduce both seed yield and germination. HS during germination and early vegetative stage resulted in poor emergence and stunted plant growth along with detrimental effects on physiological functions of the pea plant. To combat HS and continue its life cycle, plants use various defense strategies including heat escape, avoidance or tolerance mechanisms. Ironically, the threshold temperatures for pea plant and its responses are inconsistent and not yet clearly identified. Trait discovery through traditional breeding such as semi leaflessness (afila), upright growing habit, lodging tolerance, lower canopy temperature and small seeded nature has highlighted their utility for greater adaptation under HS in pea. Screening of crop gene pool and landraces for HS tolerance in a targeted environment is a simple approach to identify HS tolerant genotypes. Thus, precise phenotyping using modern phenomics tools could lead to increased breeding efficiency. The NGS (next generation sequencing) data can be associated to find the candidate genes responsible for the HS tolerance in pea. In addition, genomic selection, genome wide association studies (GWAS) and marker assisted selection (MAS) can be used for the development of HS tolerant pea genotypes. Additionally, development of transgenics could be an alternative strategy for the development of HS tolerant pea genotypes. This review comprehensively covers the various aspects of HS tolerance mechanisms in the pea plant, screening protocols, omic advances, and future challenges for the development of HS tolerant genotypes.

Species interactions alter the selection of thermal environment in a coral reef fish.

Increasing ocean temperatures and the resulting poleward range shifts of species has highlighted the importance of a species preferred temperature and thermal range in shaping ecological communities. Understanding the temperatures preferred and avoided by individual species, and how these are influenced by species interactions is critical in predicting the future trajectories of populations, assemblages, and ecosystems. Using an automated shuttlebox system, we established the preferred temperature and upper and lower threshold temperatures (i.e., avoided temperatures) of a common coral reef fish, the black-axil chromis, Chromis atripectoralis. We then investigated how the presence of conspecifics, heterospecifics (Neopomacentrus bankieri), or a predator (Cephalopholis spiloparaea) influenced the selection of these temperatures. Control C. atripectoralis preferred 27.5 ± 1.0 °C, with individuals avoiding temperatures below 23.5 ± 0.9 °C and above 29.7 ± 0.7 °C. When associating with either conspecifics or heterospecifics, C. atripectoralis selected significantly lower temperatures (conspecifics: preferred = 21.2 ± 1.4 °C, lower threshold = 18.1 ± 0.8 °C; heterospecifics: preferred = 21.1 ± 1.1 °C, lower threshold = 19.2 ± 0.9 °C), but not higher temperatures (conspecifics: preferred = 28.9 ± 1.2 °C, upper threshold = 30.8 ± 0.9 °C; heterospecifics: preferred = 29.7 ± 1.1 °C, upper threshold = 31.4 ± 0.8 °C). The presence of the predator, however, had a significant effect on both lower and upper thresholds. Individual C. atripectoralis exposed themselves to temperatures ~ 5.5 °C cooler or warmer (lower threshold: 18.6 ± 0.5 °C, upper threshold: 35.2 ± 0.5 °C) than control fish before moving into the chamber containing the predator. These findings demonstrate how behavioural responses due to species interactions influence the thermal ecology of a tropical reef fish; however, there appears to be limited scope for individuals to tolerate higher temperatures unless faced with the risk of predation.

Heat Unit Requirements of "Flame Seedless" Table Grape: A Tool to Predict Its Harvest Period in Protected Cultivation.

Greenhouse cultivation of table grapes is a challenge due to difficulties imposed by their perennial habit and chilling requirements. Despite difficulties, greenhouse cultivation allows ripening long before that in the open field. Nonetheless, for harvesting "Flame Seedless" in the most profitable periods, a cultural practices timetable has to be established. In this context, an estimation of development rate as a function of temperature becomes essential. This work puts forward a procedure to determine "Flame Seedless" threshold temperatures and heat requirements from bud break to ripening. "Flame Seedless" required an average of 1633 growing degree days (GDD) in the open field with a base temperature of 5 °C and an upper threshold temperature of 30 °C. Strikingly, only 1542 GDD were required within the greenhouse. This procedure forecast "Flame Seedless" ripening with an accuracy of three and six days in the open field and greenhouse, improving predictions based on the average number of days between bud break and ripening. The procedure to predict oncoming harvest date was found satisfactory, just four days earlier than the real date. If we used the typical meteorological year instead of the average year, then the prediction was greatly improved since harvest was forecast just one day before its occurrence.

Radial stem growth dynamics and phenology of a multi-stemmed species (Corylus avellana L.) across orchards in the Northern and Southern hemispheres.

Climate change and the global economy impose new challenges in the management of food-producing trees and require studying how to model plant physiological responses, namely growth dynamics and phenology. Hazelnut (Corylus avellana L.) is a multi-stemmed forest species domesticated for nut production and now widely spread across different continents. However, information on stem growth and its synchronization with leaf and reproductive phenology is extremely limited. This study aimed at (i) defining the sequencing of radial growth phases in hazelnut (onset, maximum growth and cessation) and the specific temperature triggering stem growth; and (ii) combining the stem growth phases with leaf and fruit phenology. Point dendrometers were installed on 20 hazelnut trees across eight orchards distributed in the Northern and Southern hemisphere during a period of three growing seasons between 2015 and 2018. The radial growth variations and climatic parameters were averaged and recorded every 15 min. Leaf and reproductive phenology were collected weekly at each site. Results showed that stem radial growth started from day of year 84 to 134 in relation to site and year but within a relatively narrow range of temperature (from 13 to 16.5 °C). However, we observed a temperature-related acclimation in the cultivar Tonda di Giffoni. Maximum growth always occurred well before the summer solstice (on average 35 days) and before the maximum annual air temperatures. Xylogenesis developed rapidly since the time interval between onset and maximum growth rate was about 3 weeks. Importantly, the species showed an evident delay of stem growth onset with respect to leaf emergence (on average 4-6 weeks) rarely observed in tree species. These findings represent the first global analysis of radial growth dynamics in hazelnut, which is an essential step for developing models on orchard functioning and management on different continents.

Analysis on Effectiveness of Impact Based Heatwave Warning Considering Severity and Likelihood of Health Impacts in Seoul, Korea.

Many countries are operating a heatwave warning system (HWWS) to mitigate the impact of heatwaves on human health. The level of heatwave warning is normally determined by using the threshold temperature of heat-related morbidity or mortality. However, morbidity and mortality threshold temperatures have not been used together to account for the severity of health impacts. In this study, we developed a heatwave warning system with two different warning levels: Level-1 and Level-2, by analyzing the severity and likelihood of heat-related morbidity and mortality using the generalized additive model. The study particularly focuses on the cases in Seoul, South Korea, between 2011 and 2018. The study found that the threshold temperature for heat-related morbidity and mortality are 30 °C and 33 °C, respectively. Approximately 73.1% of heat-related patients visited hospitals when temperature was between 30 °C and 33 °C. We validated the developed HWWS by using both the threshold temperatures of morbidity and mortality. The area under curves (AUCs) of the proposed model were 0.74 and 0.86 at Level-1 and Level-2, respectively. On the other hand, the AUCs of the model using only the mortality threshold were 0.60 and 0.86 at Level-1 and Level-2, respectively. The AUCs of the model using only the morbidity threshold were 0.73 and 0.78 at Level-1 and Level-2, respectively. The results suggest that the updated HWWS can help to reduce the impact of heatwaves, particularly on vulnerable groups, by providing the customized information. This also indicates that the HWWS could effectively mitigate the risk of morbidity and mortality.

A specialized pore turret in the mammalian cation channel TRPV1 is responsible for distinct and species-specific heat activation thresholds.

The transient receptor potential vanilloid 1 (TRPV1) channel is a heat-activated cation channel that plays a crucial role in ambient temperature detection and thermal homeostasis. Although several structural features of TRPV1 have been shown to be involved in heat-induced activation of the gating process, the physiological significance of only a few of these key elements has been evaluated in an evolutionary context. Here, using transient expression in HEK293 cells, electrophysiological recordings, and molecular modeling, we show that the pore turret contains both structural and functional determinants that set the heat activation thresholds of distinct TRPV1 orthologs in mammals whose body temperatures fluctuate widely. We found that TRPV1 from the bat Carollia brevicauda exhibits a lower threshold temperature of channel activation than does its human ortholog and three bat-specific amino acid substitutions located in the pore turret are sufficient to determine this threshold temperature. Furthermore, the structure of the TRPV1 pore turret appears to be of physiological and evolutionary significance for differentiating the heat-activated threshold among species-specific TRPV1 orthologs. These findings support a role for the TRPV1 pore turret in tuning the heat-activated threshold, and they suggest that its evolution was driven by adaption to specific physiological traits among mammals exposed to variable temperatures.

Evidence of Adaptation to Increasing Temperatures.

In times of rising temperatures, the question arises on how the human body adapts. When assumed that changing climate leads to adaptation, time series analysis should reveal a shift in optimal temperatures. The city of Vienna is especially affected by climate change due to its location in the Alpine Range in Middle Europe. Based on mortality data, we calculated shifts in optimal temperature for a time period of 49 years in Vienna with Poisson regression models. Results show a shift in optimal temperature, with optimal temperature increasing more than average temperature. Hence, results clearly show an adaptation process, with more adaptation to warmer than colder temperatures. Nevertheless, some age groups remain more vulnerable than others and less able to adapt. Further research focusing on vulnerable groups should be encouraged.

p53 Protects Cells from Death at the Heatstroke Threshold Temperature.

When the core body temperature is higher than 40°C, life is threatened due to heatstroke. Tumor repressor p53 is required for heat-induced apoptosis at hyperthermia conditions (>41°C). However, its role in sub-heatstroke conditions (≤40°C) remains unclear. Here, we reveal that both zebrafish and human p53 promote survival at 40°C, the heatstroke threshold temperature, by preventing a hyperreactive heat shock response (HSR). At 40°C, both Hsf1 and Hsp90 are activated. Hsf1 upregulates the expression of Hsc70 to trigger Hsc70-mediated protein degradation, whereas Hsp90 stabilizes p53 to repress the expression of Hsf1 and Hsc70, which prevents excessive HSR to maintain cell homeostasis. Under hyperthermia conditions, ATM is activated to phosphorylate p53 at S37, which increases BAX expression to induce apoptosis. Furthermore, growth of p53-deficient tumor xenografts, but not that of their p53+/+ counterparts, was inhibited by 40°C treatment. Our findings may provide a strategy for individualized therapy for p53-deficient cancers.

[Threshold temperature and effective accumulative temperature of Periplaneta Americana].

Periplaneta americana is an important medicinal insect. A series of new drugs developed from it have remarkable clinical effects and are in great demand in the market. Because of unclear biology, the quality and yield of P. americana are affected. Understanding the developmental threshold temperature and effective accumulated temperature of P. americana can provide theoretical basis for standardized culture of P.americana. Under climate chamber, the threshold temperature and effective accumulated temperature for egg development of P. americana to were determined through effective accumulated temperature law. The threshold temperature was （15.8±0.71）°C, the effective accumulated temperature was 415.8±38.05 degree days. A model of the relationship between temperature and developmental rates was established.

Temperature-dependent development and freezing survival of protostrongylid nematodes of Arctic ungulates: implications for transmission.

BACKGROUND: Umingmakstrongylus pallikuukensis and Varestrongylus eleguneniensis are two potentially pathogenic lungworms of caribou and muskoxen in the Canadian Arctic. These parasites are currently undergoing northward range expansion at differential rates. It is hypothesized that their invasion and spread to the Canadian Arctic Archipelago are in part driven by climate warming. However, very little is known regarding their physiological ecology, limiting our ability to parameterize ecological models to test these hypotheses and make meaningful predictions. In this study, the developmental parameters of V. eleguneniensis inside a gastropod intermediate host were determined and freezing survival of U. pallikuukensis and V. eleguneniensis were compared. METHODS: Slug intermediate hosts, Deroceras laeve, were collected from their natural habitat and experimentally infected with first-stage larvae (L1) of V. eleguneniensis. Development of L1 to third-stage larvae (L3) in D. laeve was studied at constant temperature treatments from 8.5 to 24 °C. To determine freezing survival, freshly collected L1 of both parasite species were held in water at subzero temperatures from -10 to -80 °C, and the number of L1 surviving were counted at 2, 7, 30, 90 and 180 days. RESULTS: The lower threshold temperature (T0) below which the larvae of V. eleguneniensis did not develop into L3 was 9.54 °C and the degree-days required for development (DD) was 171.25. Both U. pallikuukensis and V. eleguneniensis showed remarkable freeze tolerance: more than 80% of L1 survived across all temperatures and durations. Larval survival decreased with freezing duration but did not differ between the two species. CONCLUSION: Both U. pallikuukensis and V. eleguneniensis have high freezing survival that allows them to survive severe Arctic winters. The higher T0 and DD of V. eleguneniensis compared to U. pallikuukensis may contribute to the comparatively slower range expansion of the former. Our study advances knowledge of Arctic parasitology and provides ecological and physiological data that can be useful for parameterizing ecological models.

Effect of Temperature on the Development, Survival, and Fecundity of Heliothis viriplaca (Lepidoptera: Noctuidae).

Heliothis viriplaca (Hüfnagel) (Lepidoptera: Noctuidae) is worldwide an important economic pest of major agricultural crops. The effect of temperature on the biology, in particular the duration of the different developmental stages, of this insect pest was examined. The development, survival, and fecundity of H. viriplaca at five different temperatures (22, 25, 28, 31, and 34°C) were investigated, and experimental population life tables calculated. The results show that the developmental time of larvae, pupae, pre-oviposition, adults, and the entire generation decreases with increasing temperature. Larvae emerged fastest from the eggs at 28°C. The percentage of larvae that reached the seventh instar stage was 32.69, 38.60, 19.67, 3.61, and 20.88% at 22, 25, 28, 31, and 34°C, respectively. The developmental threshold temperature of the eggs, larvae, pupae, pre-oviposition and total pre-oviposition period was 10.53, 12.34, 5.60, 11.47, and 10.01°C, respectively. The effective accumulative temperature was 42.90, 239.68, 309.19, 77.72, and 767.64 degree-days, respectively. The population trend index (I) and the intrinsic rate of increase (r) of H. viriplaca were the highest at 31°C (133.97 and 0.12 d-1, respectively). The results of this study may be useful for predicting the population dynamics of H. viriplaca and thus provides information on this important insect pest that may assist in its management.

Threshold temperature and effective accumulative temperature of Periplaneta Americana / 中国中药杂志

Periplaneta americana is an important medicinal insect. A series of new drugs developed from it have remarkable clinical effects and are in great demand in the market. Because of unclear biology, the quality and yield of P. americana are affected. Understanding the developmental threshold temperature and effective accumulated temperature of P. americana can provide theoretical basis for standardized culture of P.americana. Under climate chamber, the threshold temperature and effective accumulated temperature for egg development of P. americana to were determined through effective accumulated temperature law. The threshold temperature was （15.8±0.71）°C, the effective accumulated temperature was 415.8±38.05 degree days. A model of the relationship between temperature and developmental rates was established.

[Effects of temperature on the growth, development and reproduction of Dysmicoccus neobrevipes Beardsley (Hemiptera: Pseudococcidae).] / æ¸©åº¦å¯¹æ–°è èç°ç²‰èš§ç”Ÿé•¿å‘è‚²å’Œç¹æ®–çš„å½±å“.

In recent years, Dysmicoccus neobrevipes Beardsley (Hemiptera: Pseudococcidae) is found as one of important alien species in China. For the alien pest, temperature always is a crucial factor on constructing stable population. In this study, the development and reproduction of D. neobrevipes population of pumpkin under different temperatures were investigated. The developmental duration, developmental rate, survival rate and fecundity of D. neobrevipes were compared in the laboratory under the conditions of 17, 20, 23, 26, 29 and 32 ℃, photoperiod 14L:10D, RH (75±5)%, and the life table of the laboratory population was constructed. The results showed that in 20-29 ℃, the developmental durations of every stage of D. neobrevipes all decreased with the increasing temperature; under 20 ℃, both female and male nymph D. neobrevipes had the longest duration, being 46.95 and 50.26 d, respectively. The female and male nymph D. neobrevipes grew most fast under 29 ℃ (20.28 d) and 32 ℃ (20.70 d). The relationship between the developmental rate and temperature for each stage could be simulated by the quadratic regression. In addition, we found that the temperature could impact the survival rate of D. neobrevipes. The highest survival rate of D. neobrevipes was recorded at 29 ℃ for both female (70.3%) and male (69.3%) nymphs. The developmental threshold temperature of female and male was 13.80 ℃ and 11.61 ℃, and the accumulated temperature of female and male was 491.50 and 388.85 day-degrees, respectively. Both pre-oviposition duration and adult longevity decreased with increasing temperature, and the highest fecundity per female was 442.2 eggs at 29 ℃, and the lowest 111.8 eggs at 20 ℃. The population trend indexes under 20 ℃ and 29 ℃ were 19.1 and 168.2, respectively. At 17 ℃ and 32 ℃, D. neobrevipes of the 1st instar nymphs and 3rd instar nymphs were found to stop growth, suggesting that excessively high or low temperature was unfavorable to the growth of D. neobrevipes. In conclusion, temperature could significantly affect the growth and development, survivorship, reproduction and population increasing of D. neobrevipes, and the most suitable temperature range for this pest is from 23 ℃ to 29 ℃.

Temperature dependence of needle and shoot elongation before bud break in Scots pine.

Knowledge about the early part of needle growth is deficient compared with what is known about shoot growth. It is however important to understand growth of different organs to be able to estimate the changes in whole tree growth in a changing environment. The onset of growth in spring has been observed to occur over some certain threshold value of momentary temperature or temperature accumulation. We measured the length growth of Scots pine (Pinus sylvestris L.) needles and shoots from March until bud break over 3 years. We first compared needle growth with concurrent shoot growth. Then, we quantified threshold temperature of growth (i) with a logistic regression based on momentary temperatures and (ii) with the temperature sum accumulation method. Temperature sum was calculated with combinations of various time steps, starting dates and threshold temperature values. Needle elongation began almost concurrently with shoot elongation and proceeded linearly in relation to shoot growth until bud break. When studying the threshold temperature for growth, the method with momentary temperature effect on growth onset yielded ambiguous results in our conditions. The best fit of an exponential regression between needle growth or length and temperature sum was obtained with threshold temperatures -1 to +2 °C, with several combinations of starting date and time step. We conclude that although growth onset is a momentary event the process leading to it is a long-term continuum where past time temperatures have to be accounted for, rather than a sudden switch from quiescence to active growth. Further, our results indicate that lower temperatures than the commonly used +5 °C are sufficient for actuating the growth process.

Larval development rates of Chrysomya rufifacies Macquart, 1842 (Diptera: Calliphoridae) within its native range in South-East Asia.

Chrysomya rufifacies represents an important indicator species in forensic entomology that is often used to estimate the minimum postmortem interval (PMImin) in crime scene investigation. However, developmental rates differ locally, so that estimates should be based on regionally generated development data. Therefore, we determined the developmental rates of C. rufifacies within its native range in Thailand under nine constant temperature regimes: 15, 18, 21, 24, 27, 30, 33, 36 and 39°C. Developmental times from egg to adult varied among the temperatures and were longest at 15°C (618h) and shortest at 33°C (168h). No pupae emerged at 39°C. We used linear regression models to estimate the minimum development threshold temperatures for each life stage: egg stage=9.5°C, first to second instar=10.8°C, second to third instar=11.5°C, third instar to pupariation=11.4°C, pupariation to adults=5.0°C; the minimum threshold to complete all larvae stages was 11.1°C and to complete all life stages from eggs to adult was 9.5°C. We further generated isomorphen and isomegalen diagrams that can be used to quickly estimate the PMImin for forensic applications.