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Tomato is the most preferred host plant for Tuta absoluta, a newly emerged devastating invasive pest in China. However, no study has evaluated the damage risk of T. absoluta on processed tomato worldwide. In the current study, the life table parameters of T. absoluta were systematically investigated on five tomato cultivars (one fresh tomato cultivar, four processed tomato cultivars) to determine their susceptibility to T. absoluta infestation. T. absoluta had a better population growth ability on the fresh tomato, "Dafen", showing shorter duration of the preadult stage, higher lifetime fecundity, and a higher intrinsic rate of increase compared to four processed tomato cultivars. Meanwhile, the life table parameters of T. absoluta among different processed tomato cultivars also showed significant differences. Th9 was the most susceptible to T. absoluta attack, while Th1902, Heinz1015, and Dimen2272 were the least suitable ones for its development and reproduction. In summary, these tomato cultivars are the most recommended for commercial tomato production to reduce the damage caused by T. absoluta and improve the integrated pest management strategy.

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In holometabolous insects, life-history characteristics can vary in response to diet. The main aim of this contribution was to examine which diet best promotes larval development and survival of the aquatic saprophagous hoverfly Eristalis tenax L. (Diptera: Syrphidae). This study was motivated by a need to optimize techniques for rearing these insects in captivity. We studied how adding yeast to several rearing media based on animal droppings or decaying plant material affected development and survival in captive larvae, and whether these effects could be optimized depending on the amount of yeast and the rearing medium. In addition, premature exit of larvae was examined in two medium volumes to investigate differences in pupation. Larvae in yeast supplemented rabbit growth medium pupated and emerged faster than those in horse and antelope growth media. A high number of adult females emerged when compared to males, and both seemed to have a shorter developmental period in yeast supplemented growth media. Pupal survival was significantly greater in a mixture of droppings and plant organic matter, and a high medium volume of 140 ml (p < 0.05). Between 10% and 17% of larvae prematurely exited the aquatic medium in high (140) and low (70 ml) medium volumes, respectively. These results provide additional information that may be crucial for the successful mass rearing of E. tenax in captivity, and suggest that apart from the addition of yeast, growth medium quality and volume may be limiting factors for the production of large colonies of adults.

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Despite their importance as ecological indicators of anthropic perturbation, most of our knowledge about Neotropical dung beetles (Coleoptera: Scarabaeinae) is derived from studies conducted at the community level. To date, at a global scale, there is still incipient knowledge about the population ecology of the Scarabeinae species. The study of these insects at the population level offers new data pertaining to demographic aspects such as population size and adult longevity in the field. On the 6th of August 2017, within a patch of a cloud forest in the municipality of La Celia in Risaralda, Colombia, we recaptured a male specimen of Dichotomius aff. alyattes Harold that was marked 5 years ago, on the 15th of May 2012. The individual was marked with a number 8 on its right elytron and it was recaptured in the same patch forest, which has been sampled since 2008. After an exhaustive review of the field information and literature, this data represents the longest recorded longevity known for Scarabaeinae. Beyond being a fortuitous event, this recapture prompts a review of our ideas regarding the reproductive biology and vulnerability of dung beetle species in landscapes of high anthropic demand, with an emphasis on Neotropical species.

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The olive fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), is a key-pest in the main olives producing areas worldwide, and displays distinct preference to different olive cultivars. The present work intended to study oviposition preference towards three Portuguese cultivars (Cobrançosa, Madural, and Verdeal Transmontana) at different maturation indexes. Multiple oviposition bioassays (multiple-choice and no-choice) were conducted to assess cultivar preference. No-choice bioassays were conducted to assess the influence of different maturation indexes (MI 2; MI 3, and MI 4) in single cultivars. The longevity of olive fly adults according to the cultivar in which its larvae developed was also evaluated through survival assays.Cultivar and maturation are crucial aspects in olive fly preference. Field and laboratory assays revealed a preference towards cv. Verdeal Transmontana olives and a lower susceptibility to cv. Cobrançosa olives. A higher preference was observed for olives at MI 2 and MI 3. The slower maturation process in cv. Verdeal Transmontana (still green while the other cultivars are reddish or at black stage) seems to have an attractive effect on olive fly females, thus increasing its infestation levels. Olive fly adults from both sexes live longer if emerged from pupae developed from cv. Verdeal Transmontana fruits and live less if emerged from cv. Cobrançosa. Therefore, olive cultivar and maturation process are crucial aspects in olive fly preference, also influencing the longevity of adults.

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Edible insects have become a recognized alternative and sustainable source of high-quality proteins and fats for livestock or human consumption. In the production process of black soldier fly (BSF), (Hermetia illucens L. [Diptera: Stratiomyidae]), initial substrate pH is a critical parameter to ensure the best value of insect biomass, life history traits, and quality bio-fertilizer. This study examined the impact of initial pH values on BSF larvae production, development time, and adult longevity. The BSF were reared on artificial diet with initial pH of 2.0, 4.0, 6.0, 8.0, and 10.0; the control was set at 7.0. Final BSF larval weight was significantly greater in substrates having initial pH 6.0 (0.21 g), control 7.0 (0.20 g), and 10.0 (0.20 g) with no significant difference among them, whereas larval weight reared with initial pH 2.0 and 4.0 were lowest at 0.16 g (-23%). Prepupal weight was greatest when larvae were reared on substrates with initial pH 6.0 (0.18 g), control 7.0 (0.19 g), 8.0 (0.18 g), and 10.0 (0.18 g). In contrast, the prepupal weight of larvae reared on diets with initial pH 2.0 was lowest at 0.15 g (-22%). Larval development time was 21.19 d at pH 8.0, about 3 d (12.5%) shorter than that of those reared on diets with initial pH 6.0, 7.0 control, and 10.0. In all treatments, pH shifted to 5.7 after 3-4 d and 8.5 after 16-17 d except for two groups (2.0 and 4.0) where the pH remained slightly acidic 5.0 and 6.5, respectively.

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The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) MEAM1 is a serious pest of many crops worldwide, and its control mostly depends on insecticides. One of the most preferred host plants of B. tabaci is eggplant, Solanum melongena, although preferences among different cultivars of the whiteflies vary. We hypothesized that certain nutritional and defensive chemicals of plant leaves, such as nitrogen, glucose, fructose, sucrose, amino acids, total phenolic components, and moisture content may affect whitefly's feeding and ovipositional preference, fecundity and longevity, nymph development, and survival among different eggplant varieties. To seek the most susceptible eggplant variety for use as an attractive trap crop for whitefly adults, we determined the variation of leaf chemical compositions among six eggplant varieties (H149, JSZ, JGL, TLB, DYZ, and QXN) and evaluated the effects of their leaf chemicals to the performance of nymphs and adults of B. tabaci. In choice feeding and oviposition tests, the varieties 'H149' and 'JSZ' had the most eggs. The whiteflies had significantly higher fecundity, longevity, lowest nymph development period, and higher survivals on JSZ than on other varieties. The least preferred TLB variety possessed the lowest adults and eggs, the lowest fecundity and longevity, and nymph development period. JGL, DYZ, and QXN were considered as a moderately preferred variety. Leaf chemistry revealed that highly susceptible variety possessed higher concentration of nitrogen, glucose, amino acids, and lower moisture content. The resistant variety possessed higher amount of total phenolic component. Both nutritional and defensive chemicals combined associated with nymph and adult performance of whitefly.

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BACKGROUND: Temperature plays a crucial role in the life history of insects. Recent climate change research has highlighted the importance of elevated temperature on malaria vector distribution. This study aims to examine the role of elevated temperatures on epidemiologically important life-history traits in the major malaria vector, Anopheles arabiensis. Specifically, the differential effects of temperature on insecticide-resistant and susceptible strains were examined. METHODS: Two laboratory strains of A. arabiensis, the insecticide-susceptible SENN and the insecticide-resistant SENN DDT strains, were used to examine the effect of elevated temperatures on larval development and adult longevity. The effects of various elevated temperatures on insecticide resistance phenotypes were also examined and the biochemical basis of the changes in insecticide resistance phenotype was assessed. RESULTS: SENN and SENN DDT larvae developed at similar rates at elevated temperatures. SENN DDT adult survivorship did not vary between control and elevated temperatures, while the longevity of SENN adults at constantly elevated temperatures was significantly reduced. SENN DDT adults lived significantly longer than SENN at constantly elevated temperatures. Elevated rearing temperatures, as well as a short-term exposure to 37 and 39 °C as adults, augmented pyrethroid resistance in adult SENN DDT, and increased pyrethroid tolerance in SENN. Detoxification enzyme activity was not implicated in this phenotypic effect. Quercertin-induced synergism of inducible heat shock proteins negated this temperature-mediated augmentation of pyrethroid resistance. CONCLUSION: Insecticide-resistant A. arabiensis live longer than their susceptible counterparts at elevated temperatures. Exposure to heat shock augments pyrethroid resistance in both resistant and susceptible strains. This response is potentially mediated by inducible heat shock proteins.

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BACKGROUND: The calliphorid Cynomyamortuorum (L., 1761) is a species of forensic interest, present mainly in the Palaearctic Region. Nearly nothing is known about its life history. NEW INFORMATION: We provide here the first data regarding pupal weight evolution during the pupal stage, female fertility and life expectancy of the species. At 22°C under a variable regime of temperatures, the egg-to-adult development time was an average of 18.05 ± 0.72 and 18.47 ± 0.67 days for females and males, respectively, in the control group. The pupal stage represented 56.7% of the total development. The development time from egg to adult and the duration of the pupal stage were significantly longer for males than for females. The measurement of pupal weight at the start of the pupal period revealed that female pupae were significantly lighter than male pupae by nearly 20%. This difference between the sexes was also observed for the dry weight of adults. An average decrease of 8.75% was observed throughout the first 8 days of the pupal stage, after which most adults started to emerge. The tested females produced an average of 176.13 ± 66.62 eggs throughout the egg-laying period. The average lifespan after emergence was 12.10 ± 4.09 days for females and 12.60 ± 2.95 days for males, with a median of 12.50 days for both sexes.

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The effect of temperature on the biology of Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae) is well understood under constant temperature conditions, but less so under more natural, fluctuating conditions. Herein we studied the influence of fluctuating temperatures on biological parameters of V. canescens. Parasitized fifth-instar larvae of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) were reared individually in incubators at six fluctuating temperature regimes (15-19.5°C with a mean of 17.6°C, 17.5-22.5°C with a mean of 19.8°C, 20-30°C with a mean of 22.7°C, 22.5-27.5°C with a mean of 25°C, 25.5-32.5°C with a mean of 28.3°C and 28.5-33°C with a mean of 30°C) until emergence and death of V. canescens adults. Developmental time from parasitism to adult eclosion, adult longevity and survival were recorded at each fluctuating temperature regime. In principle, developmental time decreased with an increase of the mean temperature of the fluctuating temperature regime. Upper and lower threshold temperatures for total development were estimated at 34.9 and 6.7°C, respectively. Optimum temperature for development and thermal constant were 28.6°C and 526.3 degree days, respectively. Adult longevity was also affected by fluctuating temperature, as it was significantly reduced at the highest mean temperature (7.0 days at 30°C) compared to the lowest one (29.4 days at 17.6°C). Survival was low at all tested fluctuating temperatures, apart from mean fluctuating temperature of 25°C (37%). Understanding the thermal biology of V. canescens under more natural conditions is of critical importance in applied contexts. Thus, predictions of biological responses to fluctuating temperatures may be used in population forecasting models which potentially influence decision-making in IPM programs.

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