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Tuta absoluta, an economically important pest threatening the global production of tomato crops worldwide, has recently invaded China. Owing to insecticide resistance, alternative control options are needed within the context of integrated pest management (IPM) programs. Augmentative biological control using indigenous natural enemies is a promising tactic for managing T. absoluta in newly invaded areas. In this study, the host suitability of four commercialized Trichogramma parasitoids in China (T. dendrolimi, T. japonicum, T. chilonis, and T. ostriniae) on T. absoluta eggs was evaluated in laboratory conditions. The control effectiveness of the most promising Trichogramma species was further tested at different release densities and frequencies in a greenhouse experiment. We found that T. chilonis was the most promising species parasitizing T. absoluta eggs, showing the highest parasitism rate, emergence rate, and female offspring sex ratio. The greenhouse experiment indicated that 600,000 parasitoids/hectare (20 parasitoids/plant) was the most effective release density, reaching 76% control effectiveness. Release frequency significantly affected the parasitism rate in the greenhouse. Two releases of 300,000 parasitoids/hectare on Day 1 and Day 4 was the most effective strategy, compared to one release of 600,000 parasitoids/hectare on Day 1. Our findings showed that augmentative biological control of T. absoluta by native Trichogramma parasitoids T. chilonis in China is feasible, and it could be included as part of IPM package against T. absoluta in China. [ABSTRACT FROM AUTHOR]

Bactrocera tsuneonis and Bactrocera minax are the most destructive pests that damage citrus in China. These key pests hinder the citrus trade, cause significant financial losses, drastically lower citrus production and quality, and decrease farmer enthusiasm for citrus planting. Bactrocera minax and B. tsuneonis are very similar in all life stages. There are limited morphological characteristics to differentiate the adult species, and it is nearly impossible to differentiate these two species in the egg and larval stages. Loop-mediated isothermal amplification (LAMP) is a rapid and robust diagnostic tool used to identify these two species accurately. We designed two sets of primers to distinguish B. minax and B. tsuneonis using DNA barcoding region of the COI gene. Only 50 min was needed under a constant temperature of 65ºC to determine the species of the two flies. The reaction system has high specificity and sensitivity, in which these two species can be accurately distinguished between different geographical populations and 1.0 ng/μL was the lowest DNA concentration that could be detected. Our primers can quickly identify these key pests without knowing their morphology, which could facilitate plant protection workers at the primary level to solve problems in plant quarantine. [ABSTRACT FROM AUTHOR]

The spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), distributes in most soft‐skinned fruit areas in China, is an economically important pest of fresh cherries during Sino‐European trade and is considered a quarantine pest in A2 list by European and Mediterranean Plant Protection Organization. Loop‐mediated isothermal amplification (LAMP) is an accurate, quick and convenient molecular identification method, applied to distinguish D. suzukii from other fruit flies. This method can be used for inspection in the field, and at the points of entry (POEs), because its results can be detected with the naked eye due to colour changes. In our study, first, we reported a simple and fast LAMP colorimetric detection method for molecular identification of D. suzukii. We designed primer sets for D. suzukii based on mitochondrial cytochrome oxidase I (COI) sequences. The specificity and sensitivity of the primers were tested by using target and non‐target fruit flies in the family Drosophilidae and Tephritidae, usually intercepted during the Sino‐European cherry trade. Second, for detection in the field and at POEs, the adoption of a quick DNA extraction method could save the total time of LAMP identification to about 90 min. Taken together, this accurate, quick and convenient LAMP‐based colorimetric identification assay combined with a quick DNA extraction method could visually detect clearly with just one portable heating device, which will be useful for rapid on‐site identification and inspection for D. suzukii by the quarantine department. [ABSTRACT FROM AUTHOR]

Bradysia odoriphaga is a major insect pest that infests Chinese chive in northern China. Clothianidin is a second-generation neonicotinoid insecticide that is commonly used against B. odoriphaga. In this study, the effect of sublethal clothianidin concentrations (LC5 and LC10) on key biological characteristics of B. odoriphaga was investigated using an age-stage, two-sex life table method. Bioassays results showed that clothianidin exhibited high toxicity against B. odoriphaga with LC50 of 1.898 mg L−1 following 24 h exposure. The developmental duration of larvae was significantly increased when exposed to the LC5 (0.209 mg L−1) and LC10 (0.340 mg L−1) of clothianidin. No significant effects were observed on the pupal stage, adult pre-oviposition period (APOP), total pre-oviposition period (TPOP), and mean longevities of male and female. The oviposition period and fecundity of B. odoriphaga were reduced in clothianidin-treated groups. Moreover, key demographic parameters, including the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R0), were significantly decreased by the LC5 and LC10 of clothianidin, while no effects were noted on mean generation time (T). Overall, this study showed that sublethal concentrations of clothianidin have a detrimental effect on B. odoriphaga developmental period, fecundity, and life table parameters. Therefore, clothianidin has the potential to suppress the population of B. odoriphaga even at sublethal concentrations. [ABSTRACT FROM AUTHOR]

The chive maggot, Bradysia odoriphaga (Yang and Zhang) is an economically important insect pest, affecting many key vegetables, including Chinese chive, especially in northern China. Chlorfenapyr, a halogenated pyrrole insecticide that interferes with mitochondrial oxidative phosphorylation is widely used against B. odoriphaga. In this study, we evaluated selection-induced resistance to chlorfenapyr and fitness costs in B. odoriphaga. The results showed that B. odoriphaga developed 43.32-fold resistance after continuous exposure to chlorfenapyr for over 10 consecutive generations. The life-history traits of chlorfenapyr-resistant and susceptible strains were compared using age-stage, two-sex life table approach. No significant effects were observed on the longevity and pre-adult period. However, reduction in the total pre-oviposition period (TPOP) and fecundity (eggs/female) were observed in the resistant strain. Moreover, the demographic parameters such as intrinsic rate of increase (r), net reproductive rate (R0) and finite rate of increase (λ) were also decreased significantly in the resistant strain compared to the susceptible strain. These results showed the potential of B. odoriphaga to develop resistance against chlorfenapyr under continuous selection pressure. Furthermore, there was a fitness cost linked with chlorfenapyr resistance in B. odoriphaga. We conclude that a better knowlegde on the trade-off at play between resistance degree and fitness cost could be crucial for developing further management of B. odoriphaga in China. [ABSTRACT FROM AUTHOR]

The chive maggot, Bradysia odoriphaga Yang and Zhang (Diptera: Sciaridae) is an economically important insect pest, affecting many important vegetables, including Chinese chive, especially in northern China. Clothianidin is a second-generation of neonicotinoid insecticide that is currently used for the management of B. odoriphaga. In the present study, we investigated the development of resistance after continuous laboratory selection and associated fitness costs in B. odoriphaga against clothianidin insecticide. The results showed that B. odoriphaga population developed 76-fold resistance, following exposure with clothianidin insecticide for 10 generations. Similarly, life table analysis showed that the fecundity, along with male and female longevity in a resistant strain of B. odoriphaga was decreased significantly compared with the susceptible strain. The developmental duration of larvae and pupae were increased dramatically in the resistant strain, while no effects were observed on egg hatchability. Furthermore, the demographic parameters such as the intrinsic rate of increase (r) (d-1), net reproductive rate (R0) (offspring/individual) and finite rate of increase (?) (d-1) were found to be significantly decreased in the laboratory selected resistant population when compared with the susceptible strain of B. odoriphaga, in addition, only mean generation time (T) (d) increased significantly. These results suggest that B. odoriphaga responded quickly and develop a high level of resistance against clothianidin insecticide under continuous selection pressure. Additionally, the associated fitness costs may have direct implication for the management of B. odoriphaga against clothianidin. [ABSTRACT FROM AUTHOR]

The objective of the studies presented in this Research Communication was to investigate the association of single nucleotide polymorphisms present in the MAP4K4 gene with different milk traits in dairy cows. Based on previous QTL fine mapping results on bovine chromosome 11, the MAP4K4 gene was selected as a candidate gene to evaluate its effect on somatic cell count and milk traits in ChineseHolstein cows. Milk production traits including milk yield, fat percentage, and protein percentage of each cow were collected using 305 d lactation records. Association between MAP4K4 genotype and different traits and Somatic Cell Score (SCS) was performed using General Linear Regression Model of R. Two SNPs at exon 18 (c.2061T > G and c.2196T > C) with genotype TT in both SNPs were found significantly higher for somatic SCS. We found the significant effect of exon 18 (c.2061T > G) on protein percentage, milk yield and SCS. We identified SNPs at different location of MAP4K4 gene of the cattle and several of them were significantly associated with the somatic cell score and other different milk traits. Thus, MAP4K4 gene could be a useful candidate gene for selection of dairy cattle against mastitis and the identified polymorphisms might potentially be strong genetic markers. [ABSTRACT FROM AUTHOR]

How herbivorous insects adapt to host plants is a key question in ecological and evolutionary biology. The fall armyworm, (FAW) Spodoptera frugiperda (J.E. Smith), although polyphagous and a major pest on various crops, has been reported to have a rice and corn (maize) feeding strain in its native range in the Americas. The species is highly invasive and has recently established in China. We compared behavioral changes in larvae and adults of a corn population (Corn) when selected on rice (Rice) and the molecular basis of these adaptational changes in midgut and antennae based on a comparative transcriptome analysis. Larvae of S. frugiperda reared on rice plants continuously for 20 generations exhibited strong feeding preference for with higher larval performance and pupal weight on rice than on maize plants. Similarly, females from the rice selected population laid significantly more eggs on rice as compared to females from maize population. The most highly expressed DEGs were shown in the midgut of Rice vs. Corn. A total of 6430 DEGs were identified between the populations mostly in genes related to digestion and detoxification. These results suggest that potential adaptations for feeding on rice crops, may contribute to the current rapid spread of fall armyworm on rice crops in China and potentially elsewhere. Consistently, highly expressed DEGs were also shown in antennae; a total of 5125 differentially expressed genes (DEGs) s were identified related to the expansions of major chemosensory genes family in Rice compared to the Corn feeding population. These results not only provide valuable insight into the molecular mechanisms in host plants adaptation of S. frugiperda but may provide new gene targets for the management of this pest. [ABSTRACT FROM AUTHOR]

As heatwaves increase and intensify worldwide, so has the research aimed at outlining strategies to protect individuals from their impact. Interventions that promote adaptive measures to heatwaves are encouraged, but evidence on how to develop such interventions is still scarce. Although the Health Belief Model is one of the leading frameworks guiding behavioral change interventions, the evidence of its use in heatwave research is limited. This rapid review aims to identify and describe the main themes and key findings in the literature regarding the use of the Health Belief Model in heatwaves research. It also highlights important research gaps and future research priorities. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 10 articles were included, with a geographic distribution as follows: United States (n = 1), Australia (n = 1), Pakistan (n = 1), and China (n = 1), as well as Malaysia (n = 2), Germany (n = 1), and Austria (n = 1). Results showed a lack of research using the Health Belief Model to study heatwaves induced by climate change. Half of the studies assessed heatwave risk perception, with the 2 most frequently used constructs being Perceived Susceptibility and Perceived Severity. The Self-efficacy construct was instead used less often. Most of the research was conducted in urban communities. This review underscores the need for further research using the Health Belief Model.