Identification and RNAi-based function analysis of trehalase family genes in Frankliniella occidentalis (Pergande).

BACKGROUND: Insects utilize trehalases (TREs) to regulate energy metabolism and chitin biosynthesis, which are essential for their growth, development, and reproduction. TREs can therefore be used as potential targets for future insecticide development. However, the roles of TREs in Frankliniella occidentalis (Pergande), a serious widespread agricultural pest, remain unclear. RESULTS: Three TRE genes were identified in F. occidentalis and cloned, and their functions were then investigated via feeding RNA interference (RNAi) and virus-induced gene silencing (VIGS) assays. The results showed that silencing FoTRE1-1 or FoTRE1-2 significantly decreased expression levels of FoGFAT, FoPGM, FoUAP, and FoCHS, which are members of the chitin biosynthesis pathway. Silencing FoTRE1-1 or FoTRE2 significantly down-regulated FoPFK and FoPK, which are members of the energy metabolism pathway. These changes resulted in 2-fold decreases in glucose and glycogen content, 2-fold increases in trehalose content, and 1.5- to 2.0-fold decreases in chitinase activity. Furthermore, knocking down FoTRE1-1 or FoTRE1-2 resulted in deformed nymphs and pupae as a result of hindered molting. The VIGS assay for the three FoTREs revealed that FoTRE1-1 or FoTRE2 caused shortened ovarioles, and reduced egg-laying and hatching rates. CONCLUSION: The results suggest that FoTRE1-1 and FoTRE1-2 play important roles in the growth and development of F. occidentalis, while FoTRE1-1 and FoTRE2 are essential for its reproduction. These three genes could be candidate targets for RNAi-based management and control of this destructive agricultural pest. © 2024 Society of Chemical Industry.

A novel and efficient murine model for investigating tendon-to-bone healing.

BACKGROUND: Tendon-to-bone healing is a critical challenge in sports medicine, with its cellular and molecular mechanisms yet to be explored. An efficient murine model could significantly advance our understanding of this process. However, most existing murine animal models face limitations, including a propensity for bleeding, restricted operational space, and a steep learning curve. Thus, the need for a novel and efficient murine animal model to investigate the cellular and molecular mechanisms of tendon-to-bone healing is becoming increasingly evident. METHODS: In our study, forty-four 9-week-old male C57/BL6 mice underwent transection and reattachment of the Achilles tendon insertion to investigate tendon-to-bone healing. At 2 and 4 weeks postoperatively, mice were killed for histological, Micro-CT, biomechanical, and real-time polymerase chain reaction tests. RESULTS: Histological staining revealed that the original tissue structure was disrupted and replaced by a fibrovascular scar. Although glycosaminoglycan deposition was present in the cartilage area, the native structure had been destroyed. Biomechanical tests showed that the failure force constituted approximately 44.2% and 77.5% of that in intact tissues, and the ultimate tensile strength increased from 2 to 4 weeks postoperatively. Micro-CT imaging demonstrated a gradual healing process in the bone tunnel from 2 to 4 weeks postoperatively. The expression levels of ACAN, SOX9, Collagen I, and MMPs were detected, with all genes being overexpressed compared to the control group and maintaining high levels at 2 and 4 weeks postoperatively. CONCLUSIONS: Our results demonstrate that the healing process in our model is aligned with the natural healing process, suggesting the potential for creating a new, efficient, and reproducible mouse animal model to investigate the cellular and molecular mechanisms of tendon-to-bone healing.

Comparison of Suture Button and Syndesmotic Screw for Ankle Syndesmotic Injuries: A Meta-analysis of Randomized Controlled Trials.

Background: The syndesmotic screw (SS) and suture button (SB) fixation methods are both widely used for the reduction of ankle syndesmotic injury, with varying outcomes. Purpose: To review recently published randomized controlled trials (RCTs) to assess the outcomes between SS and SB fixation for ankle syndesmotic injury. Study Design: Systematic review; Level of evidence, 1. Methods: The PubMed, Embase, ClinicalTrials.gov, and Cochrane databases were searched for relevant RCTs published between 1966 and 2021 according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Eligible studies were RCTs comparing SS and SB fixation for ankle syndesmotic injury. The risk of bias was evaluated using the Cochrane Risk of Bias tool. Primary outcomes included complications, malreduction, and unplanned reoperation, and secondary outcomes were the American Orthopaedic Foot & Ankle Society (AOFAS) score, Olerud-Molander ankle score (OMAS), and EuroQol-5 Domain (EQ-5D) score. The mean difference (MD) and risk ratio (RR) were calculated for continuous and dichotomous outcomes, respectively. Random- or fixed-effects model was applied according to heterogeneity. Results: Of 389 studies, 8 RCTs involving 512 patients were included. Overall, 257 patients received SS fixation and 255 patients received SB fixation. The 2 groups did not differ significantly in malreduction (RR, -0.06; 95% CI, -0.18 to 0.07) or EQ-5D (MD, 0.01; 95% CI, -0.01 to 0.03). However, the SB group showed significant advantages over the SS group in complications (RR, 0.42; 95% CI, 0.26 to 0.66), unplanned reoperation (RR, 0.62; 95% CI, 0.43 to 0.89), AOFAS score (MD, 3.04; 95% CI, 1.77 to 4.31), and OMAS (MD, 4.51; 95% CI, 1.54 to 7.48). The risk of bias of the included studies was acceptable. Conclusion: The results showed that there were no significant differences between the SS and SB groups in malreduction and EQ-5D scores. However, the SB group had significantly better local irritation rates, unplanned reoperation rates, AOFAS scores, and OMASs.

Tomato spotted wilt orthotospovirus shifts sex ratio toward males in the western flower thrips, Frankliniella occidentalis, by down-regulating a FSCB-like gene.

BACKGROUND: Plant viruses can facilitate their transmission by modulating the sex ratios of their insect vectors. Previously, we found that exposure to tomato spotted wilt orthotospovirus (TSWV) in the western flower thrips, Frankliniella occidentalis, led to a male-biased sex ratio in the offspring. TSWV, a generalist pathogen with a broad host range, is transmitted primarily by F. occidentalis in a circulative-propagative manner. Here, we integrated proteomic tools with RNAi to comprehensively investigate the genetic basis underlying the shift in vector sex ratio induced by the virus. RESULTS: Proteomic analysis exhibited 104 differentially expressed proteins between F. occidentalis adult males with and without TSWV. The expression of the fiber sheath CABYR-binding-like (FSCB) protein, namely FoFSCB-like, a sperm-specific protein associated with sperm capacitation and motility, was decreased by 46%. The predicted FoFSCB-like protein includes 10 classic Pro-X-X-Pro motifs and 42 phosphorylation sites, which are key features for sperm capacitation. FoFSCB-like expression was gradually increased during the development and peaked at the pupal stage. After exposure to TSWV, FoFSCB-like expression was substantially down-regulated. Nanoparticle-mediated RNAi substantially suppressed FoFSCB-like expression and led to a significant male bias in the offspring. CONCLUSION: These combined results suggest that down-regulation of FoFSCB-like in virus-exposed thrips leads to a male-biased sex ratio in the offspring. This study not only advances our understanding of virus-vector interactions, but also identifies a potential target for the genetic management of F. occidentalis, the primary vector of TSWV, by manipulating male fertility. © 2022 Society of Chemical Industry.

Sodium alginate and Chitosan aided design of form-stable Polyrotaxane based phase change materials with ultra-high latent heat.

We prepared a series of highly porous Polyrotaxane/sodium alginate, and Polyrotaxane/Chitosan foam alloys according to a sustainable pathway by using water as the only solvent. The foam alloys were further used as supporter materials for poly (ethylene glycol) (PEG) encapsulation, to fabricate shape-stable bio-based phase change materials (PCMs). The pore morphology and the internal interface between PEG and foam alloys were characterized by scanning electron microscope (SEM). Due to the good compatibility between foam alloys and PEG, the PCM performed perfect anti-leakage properties. The introduction of sodium alginate or Chitosan ensures the shape stability of the PCMs during the phase transition. The PCMs performed good cycle stability and showed ultra-high latent heat (171.6 J g-1-189.5 J g-1). Finally, we compared the typical indicators of this work with those reported in the literature, and the comparison highlighted that the present PCMs have the significant advantages: high melting enthalpy, convenient preparation and outstanding sustainability. Notably, the work provided a sustainable idea for the design of anti-leakage and shape-stable PEG-based PCMs.

Comparison of Bioabsorbable and Metallic Interference Screws for Graft Fixation During ACL Reconstruction: A Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Bioabsorbable interference screws and metallic interference screws are both widely used for graft fixation, but it remains unclear which screw type is superior. PURPOSE: To compare clinical outcomes and complications between bioabsorbable and metallic interference screws for anterior cruciate ligament reconstruction (ACLR). STUDY DESIGN: Systematic review; Level of evidence, 1. METHODS: The literature was searched for relevant randomized controlled trials published between 1966 and 2020. Two investigators independently assessed risk of bias in the included studies, and data were pooled to calculate mean differences (MDs) for continuous outcomes and risk ratios (RRs) for dichotomous outcomes, together with 95% CIs. Meta-analysis was performed using a random- or fixed-effects model, depending on the heterogeneity in the data. RESULTS: Included were 14 randomized controlled trials involving 1032 patients who underwent ACLR: 528 patients with bioabsorbable screws and 504 patients with metallic screws. The 2 groups did not differ significantly in International Knee Documentation Committee score (RR, 1.04; 95% CI, 0.97 to 1.11), Lysholm score (MD, 0.59; 95% CI, -0.46 to 1.63), range of motion deficit (RR, 0.95; 95% CI, 0.67 to 1.34), positive pivot-shift test (RR, 0.87; 95% CI, 0.61 to 1.24), positive Lachman test (RR, 0.82; 95% CI, 0.48 to 1.39), or KT-1000 arthrometer value (MD, 0.01; 95% CI, -0.16 to 0.18). However, bioabsorbable screws were associated with a significantly higher risk of complications (RR, 1.70; 95% CI, 1.16 to 2.50), such as graft rupture, joint effusion, and infection. CONCLUSION: The results of this review showed that there was no difference between metallic and bioabsorbable screws for ACLR in terms of subjective knee function or knee laxity, but metallic interference screws had fewer complications.

The Thermoperiod Alters Boper Gene Expression and Thereby Regulates the Eclosion Rhythm of Bradysia odoriphaga (Diptera: Sciaridae).

In most organisms, various physiological and behavioral functions are expressed rhythmically. Previous studies have shown that thermoperiod is an important factor affecting circadian clock-related genes that regulate insect locomotor activity. Bradysia odoriphaga Yang & Zhang is an underground pest that attacks more than 30 crops but is especially damaging to Chinese chives. In this study, we analyzed the adult eclosion time and period (Boper) gene expression in B. odoriphaga as affected by temperature (cycling vs constant temperature), insect stage, and tissue specific. We found that the eclosion time and expression of the Boper gene changed during the temperature cycle but not under a constant temperature. Silencing of Boper expression significantly decreased the adult eclosion rate and significantly increased adult mortality and malformation. The findings indicate that thermoperiod alters Boper expression and regulates the eclosion rhythm.

Highly efficient BiVO4single-crystal nanosheets with dual modification: phosphorus doping and selective Ag modification.

BiVO4, a visible-light response photocatalyst, has shown tremendous potential because of abundant raw material sources, good stability and low cost. There exist some limitations for further applicaitions due to poor capability to separate electron-hole pairs. In fact, a single-component modification strategy is barely adequate to obtain highly efficient photocatalytic performance. In this work, P substituted some of the V atoms from VO4oxoanions, namely P was doped into the V sites in the host lattice of BiVO4by a hydrothermal route. Meanwhile, Ag as an attractive and efficient electron-cocatalyst was selectively modified on the (010) facet of BiVO4nanosheets via facile photo-deposition. As a result, the obtained dually modified BiVO4sheets exhibited enhanced photocatalytic degradation property of methylene blue (MB). In detail, photocatalytic rate constant (k) was 2.285 min-1g-1, which was 2.78 times higher than pristine BiVO4nanosheets. Actually, P-doping favored the formation of O vacancies, led to more charge carriers, and facilitated photocatalytic reaction. On the other hand, metallic Ag loaded on (010) facet effectively transferred photogenerated electrons, which consequently helped electron-hole pairs separation. The present work may enlighten new thoughts for smart design and controllable synthesis of highly efficient photocatalytic materials.

Insecticide Resistance Monitoring of the Diamondback Moth (Lepidoptera: Plutellidae) Populations in China.

The diamondback moth, Plutella xylostella L., is a worldwide crop pest that is difficult to control because of its ability to develop resistance to many insecticides. To provide a reference for resistance management of P. xylostella in China, the present study used a leaf-dip bioassay to monitor the resistance of P. xylostella to nine insecticides in eight regions of China. The results showed that P. xylostella had developed a high level of resistance to beta-cypermethrin (resistance ratio [RR] > 112), and moderate (RR < 40) to high levels of resistance to indoxacarb, abamectin, and chlorfluazuron. For chlorantraniliprole, RRs > 100 were found in Midu (Yunnan Province) and Jinghai (Tianjin). In most regions, the resistance to spinetoram and chlorfenapyr and Bacillus thuringiensis (Bt) was low. No resistance was detected to diafenthiuron. Overall, P. xylostella resistance to insecticides was higher in Midu than in other regions. The data in this study should help guide the selection of insecticides for management of P. xylostella in China.

Annual analysis of field-evolved insecticide resistance in Bemisia tabaci across China.

BACKGROUND: Over recent decades, many efficacious insecticides have been applied for control of Bemisia tabaci, one of the most notorious insect pests worldwide. Field-evolved insecticide resistance in B. tabaci has developed globally, but remains poorly understood in China. RESULTS: In this study, a total of 30 field samples of the whitefly Bemisia tabaci from eight provinces of China were collected in 2015 to 2018. Twenty-four of the populations were identified as Mediterranean, 'Q' type (MED), three were Middle East-Asia Minor 1, 'B' type (MEAM1), and three were mixtures of MED/ MEAM1. After identifying whether they belong to MED or MEAM1, the selected individuals were used in bioassays assessing insecticide resistance to abamectin, thiamethoxam, spirotetramat, cyantraniliprole, and pyriproxyfen. Our results showed that all populations in the eight regions had little or no resistance to abamectin; abamectin resistance was highest in the Hunan (Changsha) and Hubei (Wuhan) regions and was lowest in the island region of Hainan (Sanya). The resistance of B. tabaci to spirotetramat, cyantraniliprole, and pyriproxyfen increased each year. The resistance to thiamethoxam remained low because of the high LC50 value for the laboratory strain. CONCLUSION: These findings suggest that a rotation system using efficacious B. tabaci insecticides with differing mode of actions ought to be implemented for sustainable control to reduce the potential of resistance development. This study provides important data to support the integrated pest management and insecticide resistance management of B. tabaci in China. © 2021 Society of Chemical Industry.

Patient-Specific or Conventional Instrumentations: A Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: To conduct a meta-analysis of randomized controlled trials (RCTs) to compare knee arthroplasty with patient-specific instrumentation (PSI) with the conventional instrumentation (CI). METHODS: RCTs were selected in PubMed and Embase from 2012 to 2018. Key data extracted included malalignment of mechanical axis, blood loss, surgical time, Oxford Knee Score (OKS), Knee Society Score (KSS), length of stay, and complications. Subgroup analysis was also performed regarding different PSI systems and different image processing methods. RESULTS: 29 RCTs with 2487 knees were eligible for the meta-analysis. Results showed that PSI did not improve the alignment of the mechanical axis compared with CI, but MRI-based PSI and Visionaire-specific PSI decrease the risk of malalignment significantly (P = 0.04 and P = 0.04 and P = 0.04 and P = 0.04 and P = 0.04 and. CONCLUSION: PSI reduced the blood loss and improved KSS. MRI-based PSI reduced operative time and risk of malalignment of mechanical axis compared with CT-based PSI. Moreover, Visionaire-specific PSI achieves better alignment result of the mechanical axis than other systems.

Tomato spotted wilt orthotospovirus influences the reproduction of its insect vector, western flower thrips, Frankliniella occidentalis, to facilitate transmission.

BACKGROUND: Tomato spotted wilt orthotospovirus (TSWV), one of the most devastating viruses of ornamental plants and vegetable crops worldwide, is transmitted by the western flower thrips, Frankliniella occidentalis (Pergande), in a persistent-propagative manner. How TSWV influences the reproduction of its vector to enhance transmission and whether infection with TSWV changes the mating behavior of F. occidentalis are not fully understood. RESULTS: TSWV-exposed thrips had a significantly longer developmental time than non-exposed individuals. More importantly, increased developmental time was predominantly associated with adults, a stage critical for dispersal and virus transmission. In addition, TSWV-exposed F. occidentalis produced substantially more progeny than did non-exposed thrips. Interestingly, most of the increase in progeny came from an increase in males, a sex with a greater dispersal and virus transmission capability. Specifically, the female/male ratio of progeny shifted from 1.3-7.0/1 to 0.6-1.1/1. As for mating behavior, copulation time was significantly longer in TSWV-exposed thrips. Finally, females tended to re-mate less when exposed to the virus. Resistance to re-mating may lead to reduced sperm availability in females, which translates to a larger number of male progeny under a haplodiploid system. CONCLUSION: These combined results suggest that TSWV can influence the developmental time, mating behavior, fecundity, and offspring sex allocation of its vector F. occidentalis to facilitate virus transmission. As such, a monitoring program capable of the earlier detection of the virus in host plants and/or its insect vector, thrips, using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), real time quantitative polymerase chain reaction (RT-qPCR) or virus detection strips might be beneficial for long-term, sustainable management. © 2020 Society of Chemical Industry.

Reduced Expression of a Novel Midgut Trypsin Gene Involved in Protoxin Activation Correlates with Cry1Ac Resistance in a Laboratory-Selected Strain of Plutella xylostella (L.).

Bacillus thuringiensis (Bt) produce diverse insecticidal proteins to kill insect pests. Nevertheless, evolution of resistance to Bt toxins hampers the sustainable use of this technology. Previously, we identified down-regulation of a trypsin-like serine protease gene PxTryp_SPc1 in the midgut transcriptome and RNA-Seq data of a laboratory-selected Cry1Ac-resistant Plutella xylostella strain, SZ-R. We show here that reduced PxTryp_SPc1 expression significantly reduced caseinolytic and trypsin protease activities affecting Cry1Ac protoxin activation, thereby conferring higher resistance to Cry1Ac protoxin than activated toxin in SZ-R strain. Herein, the full-length cDNA sequence of PxTryp_SPc1 gene was cloned, and we found that it was mainly expressed in midgut tissue in all larval instars. Subsequently, we confirmed that the PxTryp_SPc1 gene was significantly decreased in SZ-R larval midgut and was further reduced when selected with high dose of Cry1Ac protoxin. Moreover, down-regulation of the PxTryp_SPc1 gene was genetically linked to resistance to Cry1Ac in the SZ-R strain. Finally, RNAi-mediated silencing of PxTryp_SPc1 gene expression decreased larval susceptibility to Cry1Ac protoxin in the susceptible DBM1Ac-S strain, supporting that low expression of PxTryp_SPc1 gene is involved in Cry1Ac resistance in P. xylostella. These findings contribute to understanding the role of midgut proteases in the mechanisms underlying insect resistance to Bt toxins.

Foccα6, a truncated nAChR subunit, positively correlates with spinosad resistance in the western flower thrips, Frankliniella occidentalis (Pergande).

Nicotinic acetylcholine receptors (nAChRs), a molecular target for spinosyns and neonicotinoids, mediate rapid cholinergic transmission in insect central nervous system by binding acetylcholine. Previous studies have shown that mutations in nAChRs contribute to the high level of resistance to these two classes of insecticides. In this study, we identified nine nAChR subunits from a transcriptome of the western flower thrips, Frankliniella occidentalis, including α1-7, ß1, and ß2. Exon 4 of α4 and exons 3 and 8 of α6 each have two splicing variants, respectively. In addition, altered or incorrect splicing leads to truncated forms of α3, α5, and α6 subunits. The abundance of every nAChRs in both spinosad susceptible and resistant strains was highest in the 1st instar nymph. Significantly more truncated forms of α6 subunit were detected in spinosad resistant strains, whereas, hardly any full-length form was found in the two highly resistant F. occidentalis strains (resistance ratio >104-fold). Under laboratory conditions, spinosad resistance was positively correlated with truncated α6 transcripts. The correlation was later confirmed under the field conditions using five field strains. As the molecular target of spinosad, the percentage of truncated nAChR α6 subunits can be used as a diagnostic tool to detect and quantify spinosad resistance in the field.

Population dynamics of the diamondback moth, Plutella xylostella (L.), in northern China: the effects of migration, cropping patterns and climate.

BACKGROUND: The diamondback moth, Plutella xylostella (L.), is the most widely distributed pest of Brassica vegetables. Control of P. xylostella has relied on insecticides and it has developed resistance to most insecticides. Although research has clarified the resistance status of P. xylostella and the mechanisms of its resistance in northern China, little work has been conducted on long-term population dynamics in the key vegetable-growing areas of the region. RESULTS: We reviewed and summarized the history of P. xylostella field management practices in northern China (Haidian, Changping, Xuanhua and Zhangbei). Moths were caught in pheromone traps throughout the cropping season and P. xylostella phenology and the general trends in abundance were analysed using DYMEX modelling software. The initial input in the spring determined population size in all years. The seasonal phenology and variation in abundance in most years and sites were simulated, suggesting that the suitable climate creates the conditions for population outbreaks, and growers' actual management level (spraying and crop hygiene) influenced population abundance. CONCLUSION: Based on climate and using the timing of the initial peak in pheromone trap captures as a biofix, the timing of emergence of the next generation can be forecast, and more effective scouting and regional management strategies against this pest can be developed. © 2018 Society of Chemical Industry.

Fitness Trade-Off Associated With Spinosad Resistance in Frankliniella occidentalis (Thysanoptera: Thripidae).

Frankliniella occidentalis (Pergande) is an economically important pest of agricultural crops. High resistance has been detected in field populations of F. occidentalis against the insecticide spinosad. In this study, we compared life history traits, body sizes, and feeding behaviors (recorded via an electrical penetration graph) of spinosad-susceptible (Ivf03) and spinosad-resistant (NIL-R) near-isogenic lines of F. occidentalis. Life table analysis showed that NIL-R had reduced female longevity and reduced fecundity. The relative fitness of NIL-R (0.43) was less than half that of Ivf03. NIL-R individuals were smaller than Ivf03 individuals, both in body length and body width at every stage. The number and duration of feeding activities were significantly reduced in NIL-R, with the exception of total duration of long-ingestion probes. These results suggest that there is a fitness trade-off associated with spinosad resistance in F. occidentalis, and that the development of resistance in this pest species may be reduced by rotating spinosad with other pesticides lacking cross-resistance.

Odor, Not Performance, Dictates Bemisia tabaci's Selection between Healthy and Virus Infected Plants.

Although, insect herbivores are generally thought to select hosts that favor the fitness of their progeny, this "mother-knows-best" hypothesis may be challenged by the presence of a plant virus. Our previous study showed that the whitefly, Bemisia tabaci, the obligate vector for transmitting Tomato yellow leaf curl virus (TYLCV), preferred to settle and oviposit on TYLCV-infected rather than healthy host plant, Datura stramonium. The performances of B. tabaci larvae and adults were indeed improved on virus-infected D. stramonium, which is consistent with "mother-knows-best" hypothesis. In this study, B. tabaci Q displayed the same preference to settle and oviposit on Tomato spotted wilt virus (TSWV)-infected host plants, D. stramonium and Capsicum annuum, respectively. As a non-vector of TSWV, however, insect performance was impaired since adult body size, longevity, survival, and fecundity were reduced in TSWV infected D. stramonium. This appears to be an odor-mediated behavior, as plant volatile profiles are modified by viral infection. Infected plants have reduced quantities of o-xylene and α-pinene, and increased levels of phenol and 2-ethyl-1-hexanol in their headspace. Subsequent behavior experiments showed that o-xylene and α-pinene are repellant, while phenol and 2-ethyl-1-hexanol are attractive. This indicates that the preference of B. tabaci for virus-infected plants is modulated by the dynamic changes in the volatile profiles rather than the subsequent performances on virus-infected plants.

Effects of Heat Shock on the Bradysia odoriphaga (Diptera: Sciaridae).

Bradysia odoriphaga is frequently subjected to heat shock during the summer in China. Although the effects of heat shock on insect ecology and physiology have been widely explored, the effects of heat shock on the life history parameters of Bradysia odoriphaga are largely unknown. In the present study, we investigated the effects of heat shock on B. odoriphaga survival and reproduction as well as on offspring development and sex ratio. We exposed adult B. odoriphaga to 31, 33, 35, or 37 °C for different durations (from 0 to 120 min). The results showed that the survival of both sexes declined with the increase in temperature and exposure time, especially at 33, 35, and 37 °C. Longevity was markedly greater for males than females across all treatments. Fecundity generally declined as temperature and exposure time increased, and no eggs hatched when females were exposed to 37 °C for >75 min. The development of offspring larvae was significantly delayed when the parent female and male had been exposed to ≥31 °C for ≥30 min. In addition, the sex ratio of F1 progeny derived from heat-shocked parental adults was increasingly skewed to female as exposure time and temperature treatment increased. Overall, the results indicate that heat shock negatively influences B. odoriphaga.

Genome sequencing of the sweetpotato whitefly Bemisia tabaci MED/Q.

The sweetpotato whitefly Bemisia tabaci is a highly destructive agricultural and ornamental crop pest. It damages host plants through both phloem feeding and vectoring plant pathogens. Introductions of B. tabaci are difficult to quarantine and eradicate because of its high reproductive rates, broad host plant range, and insecticide resistance. A total of 791 Gb of raw DNA sequence from whole genome shotgun sequencing, and 13 BAC pooling libraries were generated by Illumina sequencing using different combinations of mate-pair and pair-end libraries. Assembly gave a final genome with a scaffold N50 of 437 kb, and a total length of 658 Mb. Annotation of repetitive elements and coding regions resulted in 265.0 Mb TEs (40.3%) and 20 786 protein-coding genes with putative gene family expansions, respectively. Phylogenetic analysis based on orthologs across 14 arthropod taxa suggested that MED/Q is clustered into a hemipteran clade containing A. pisum and is a sister lineage to a clade containing both R. prolixus and N. lugens. Genome completeness, as estimated using the CEGMA and Benchmarking Universal Single-Copy Orthologs pipelines, reached 96% and 79%. These MED/Q genomic resources lay a foundation for future 'pan-genomic' comparisons of invasive vs. noninvasive, invasive vs. invasive, and native vs. exotic Bemisia, which, in return, will open up new avenues of investigation into whitefly biology, evolution, and management.

Development of Near-Isogenic Lines in a Parthenogenetically Reproduced Thrips Species, Frankliniella occidentalis.

Although near-isogenic lines (NILs) can standardize genetic backgrounds among individuals, it has never been applied in parthenogenetically reproduced animals. Here, through multiple rounds of backcrossing and spinosad screening, we generated spinosad resistant NILs in the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), with a haplo-diploid reproduction system. The resultant F. occidentalis NIL-R strain maintained a resistance ratio over 30,000-fold, which was comparable to its parental resistant strain, Spin-R. More importantly, F. occidentalis NIL-R shared 98.90% genetic similarity with its susceptible parental strain Ivf03. By developing this toolset, we are able to segregate individual resistance and facilitate the mechanistic study of insecticide resistances in phloem-feeding arthropods, a group of devastating pest species reproducing sexually as well as asexually.