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BACKGROUND: Differences in population densities of Frankliniella occidentalis among different plant species suggest a preference for particular hosts. Host plant volatiles are often involved in insect fitness. However, few studies have explored the interaction between flower volatiles and fitness. The host fitness of F. occidentalis for different flowers was assessed through field investigation, and the olfactory preference of thrips for flower volatiles was tested in the laboratory. RESULTS: In the field study, 18 flower host plants were classified at four fitness levels by F. occidentalis. Olfactory tests showed that female F. occidentalis had significantly different preferences for different plant odours among the volatiles of the four tested flowers (each representing the four fitness levels), whereas male F. occidentalis did not. The relative response of F. occidentalis females to flower volatiles (Rosa rugosa > Dianthus caryophyllus > Gerbera jamesonii > Pelargonium hortorum) was consistent with the field performance of F. occidentalis. In total, 23, 29, 16 and 26 components were identified in the volatile profiles of R. rugosa, D. caryophyllus, G. jamesonii and P. hortorum, respectively. 3,5‐Dimethoxytoluene (24.94%), nonanal (30.42%), (E)‐3‐penten‐2‐one (52.31%) and zingiberene (29.88%) were the single most abundant components of the volatiles of R. rugosa, D. caryophyllus, G. jamesonii and P. hortorum, respectively. CONCLUSION: Volatiles are important in attracting F. occidentalis to suitable hosts, and differences in the types and concentrations of volatile components among flowers may directly influence the olfactory responses and field performance of thrips. Potential attractants could be developed for integrated pest management programmes against this pest. © 2018 Society of Chemical Industry Plant volatiles can help Frankliniella occidentalis to locate a more suitable host, and potential attractants could be developed for integrated pest management against this pest based on our results. [ABSTRACT FROM AUTHOR]

Temperature fluctuations may influence the behaviour of insects. Frankliniella occidentalis and Thrips hawaiiensis are sympatric pests on flower and vegetable host plants in China. This study evaluated the influence of constant (23.0°C) and fluctuating temperatures (average of 23.0°C) on the population development of these two species. The results showed that both of these pests showed faster development and higher fecundity at a constant temperature than at fluctuating temperatures when fed on Rosa rugosa flowers, and F. occidentalis showed faster development and higher fecundity than T. hawaiiensis under both conditions. Under the constant and fluctuating temperatures, the development times from egg to adult were 9.57 and 10.62 day for F. occidentalis and 10.71 and 11.82 day for T. hawaiiensis, respectively. The total numbers of first instar nymph produced were 103.08 and 86.32 by F. occidentalis, 86.96 and 73.32 by T. hawaiiensis, under the constant and fluctuating temperatures, respectively, and a higher intrinsic rate of natural increase (rm) (0.173 and 0.160) and R0 (46.31 and 36.86) were obtained in F. occidentalis compared with T. hawaiiensis (rm for 0.154 and 0.141 and R0 for 34.46 and 27.81, respectively). Our results indicate that the constant temperature had a positive effect on the population development of both F. occidentalis and T. hawaiiensis. Furthermore, F. occidentalis showed a stronger adaptability over T. hawaiiensis at both constant and fluctuating temperatures, according to its faster development and higher fecundity. These results may contribute to the better understanding of the biology of different thrip species, especially the interspecific competition between invasive and native thrips under the changing environment. These findings also provide basic data for the thrip pests control by using fluctuating temperatures. [ABSTRACT FROM AUTHOR]

The Western flower thrips (WFT), Frankliniella occidentalis, is a major threat to a wide range of agricultural crops and rapidly spreads throughout the world. Its international importance as a pest has led to tremendous growth in our knowledge of its biology, ecology, and novel approaches for its management. Unfortunately, the literature on WFT is widely dispersed and many researchers, extension specialists, and IPM practitioners are only now becoming aware of WFT, which has meant that management programs are still reliant on intense insecticide use, especially in recently invaded regions. Due to the current high demand in effective and sustainable control tactics for this pest, Journal of Pest Science dedicates a special issue to WFT. This special issue provides a consolidated review of WFT biology and ecology and helps to highlight alternative and novel management techniques to effectively controlling this pest in the future. [ABSTRACT FROM AUTHOR]

The Western flower thrips, Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) is an invasive polyphagous pest with an expanding global range that damages a wide variety of crops. F. occidentalis was first reported in China from Yunnan province during 2000, and has rapidly expanded its range since then. It is currently distributed across at least 10 provinces in China and has become a particularly devastating pest, causing substantial damage and economic losses. At present, the still heavy reliance on frequent use of insecticides for control of F. occidentalis, has lead to a series of ecological problems stemming from insecticide resistance, interspecific displacement and non-target effects. Thus, integrated pest management (IPM) programmes, multiple complementary tactics, including preventive tactics, biological controls, and judicious use of insecticides will likely provide a viable IPM strategy for control of F. occidentalis in the near future. This review provides an overview for information gained during the 10+ years since the invasion of F. occidentalis into China, reviews lessons that have been learned enhancing our overall understanding of the biology and ecology of F. occidentalis and discusses IPM practices relative to this widespread invasive insect pest. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Spinetoram, a new type of spinosyn with novel modes of action, has been used in effective thrips control programs, but resistance remains a threat. In the present study, a laboratory Thrips hawaiiensis population was subjected to spinetoram for resistance selection to investigate resistance development, stability, cross‐resistance potential, biological fitness and underlying biochemical mechanisms. RESULTS: Resistance to spinetoram in T. hawaiiensis rapidly increased 103.56‐fold (for 20 generations of selection with spinetoram) compared with a laboratory susceptible population, and the average realized heritability (h2) of resistance was calculated as 0.1317. Maintaining the resistant population for five generations without any further selection pressure resulted in a decline in the resistance ratio from 19.42‐ to 9.50‐fold, suggesting that spinetoram resistance in T. hawaiiensis is unstable. Moreover, the spinetoram‐resistant population exhibited a lack of cross‐resistance to other classes of insecticides, and showed biological fitness costs. The results of synergism experiments using enzyme inhibitors and biochemical analyses revealed that metabolic mechanisms might not be responsible for the development of spinetoram resistance in T. hawaiiensis. CONCLUSION: The current study expands understanding of spinosyn resistance in thrips species, providing a basis for proposing better integrated pest management strageties for thrips control programs and defining the most appropriate tools for such resistance management. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The Western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), is one of the most destructive sucking pests of flowering plants. We examined behavioral responses of F. occidentalis adults to the floral volatiles of Rosa chinensis, Gardenia jasminoides, and Tagetes erecta in a Y-tube olfactometer with background visual cues (green, red, white, yellow, and blue backgrounds). The results show that F. occidentalis adults had similar responses under all the different background colors, but the responses by sex varied significantly when offered floral volatile or clean air. In pairings of floral volatiles, female F. occidentalis adults presented significant preferences ( R. chinensis > G. jasminoides > T. erecta) in each treatment, while male F. occidentalis adults had no significant preference. Furthermore, the responses of female F. occidentalis adults to the three different floral volatiles compared with each other were greater under green and blue backgrounds than red, white, or yellow backgrounds. However, the responses of male F. occidentalis adults to floral volatiles were similar to all five backgrounds. These results indicate that female thrips could discriminate different floral volatiles, while male thrips could not. Both male and female thrips performed steady preferences of floral volatiles under all the five visual backgrounds, and the behavioral responses of female thrips to the floral volatiles could be enhanced under the green and blue backgrounds. These findings could hopefully aid in the development of effective trapping and monitoring strategies for this pest. [ABSTRACT FROM AUTHOR]

[Display omitted] • High chicken protein diet reduces body weight and fat mass of rats fed high-fat diet without affecting their feed and energy intake. • High chicken protein diet reduced blood insulin and glycosylated serum protein concentrations. • High chicken protein diet downregulated adipose tissue transcriptomics related to lipid biosynthesis. This study explored the effects of dietary chicken protein at high (HCK, 40 % E) or normal (CK, 20 % E) levels on obesity development of rats fed high-fat diets. Compared with the CK diet, the HCK diet reduced body weight gain (by 15 %), epididymal adipose tissue mass (by 18.4 %), and adipocyte size (by 18.8 %) significantly without affecting the food intake of rats. It also reduced blood insulin and glycosylated serum protein (GSP) significantly by 45.4 % and 14.3 %, respectively; however, the OGTT and HOMA-IR results were not different. The HCK diet downregulated EAT transcriptomics related to the biosynthesis of cholesterol, triglycerides, and fatty acids, which were highly correlated with the most downregulated hub genes, Insig1 , Srebf2 , Hmgcs1 , and Fasn. Therefore, high dietary chicken protein content reduced body fat accumulation, blood insulin, and GSP, and downregulated EAT transcriptomics related to lipid biosynthesis in rats fed high-fat diets. [ABSTRACT FROM AUTHOR]