Azadirachtin exhibits excellent bioactivities against several hundred arthropods. However, current knowlege of its biochemical effect on B. dorsalis larvae is not deep enough. In this study, integrated LC-MS and GC-MS-based untargeted metabolomics were used to analyze the changes of endogenous metabolites and the biochemical effects of azadirachtin on B. dorsalis larvae. Azadirachtin has excellent bioactivities against B. dorsalis larvae in this study, leading to a longer developmental duration, lower survival rate, and low pupa weight. The effect of azadirachtin was investigated on a total of 22 and 13 differentially abundant metabolites in the LC-MS and GC-MS-based metabolomics results, are selected respectively. Pathway analysis indicated that 14 differentially enriched metabolic pathways, including seven influential pathways, are worthy of attention. Further integrated key metabolic pathway analysis showed that histidine metabolism, d-glutamine and d-glutamate metabolism, biotin metabolism, ascorbate and aldarate metabolism, pentose and glucuronate interconversions, and alanine, aspartate and glutamate metabolism in B. dorsalis larvae are significantly relevant pathways affected by azadirachtin. Although extrapolating the bioactivity results in this study to the practical project of B. dorsalis pest management in the field has limitations, it was found that azadirachtin has a significant effect on the primary metabolism of B. dorsalis larvae.Bactrocera dorsalis is a destructive polyphagous and invasive insect pest of tropical and subtropical fruits and vegetables; this oriental fruit fly has been found to attack many types of commercial fruits and a wide variety of agricultural products 1 . Azadirachtin exhibits excellent bioactivities against agricultural, forestry, medical, and veterinary arthropods 2-4 . However, studies on the effects of azadirachtin on B. dorsalis are scarce. Azadirachtin is the main active ingredient in neem. It was reported that neem derivatives are ineffective when used as toxic bait for tephritid fruit flies 5 . Several studies reported that neem seed kernel extracts and azadirachtin deters oviposition of B. dorsalis adults 6,7 . Neem leaf dust significantly reduced the longevity and fertility of B. dorsalis adults by blocking ovarian development 8 . Neem extract could effectively reduce the fecundity, fertility, and post-embryonic development of freshly emerged B. dorsalis flies 9 . However, we found no previous studies in the literature on the activity of azadirachtin against the larvae of B. dorsalis.The biological effects of azadirachtin include impacts on egg-laying behavior, feeding behavior, growth and metamorphosis, reproduction, activity, and histopathology 10 . The mode of action of azadirachtin against lepidopteran insects can be explained, in part, by effects on digestive enzymes, NADPH cytochrome reductase, and cholinesterase 11 . The physiological effects of azadirachtin include direct inhibition of cell division and protein synthesis 12 . The indirect effects of blocki...

Background:To evaluate the association between fasting plasma glucose (FPG) and mortality by gender.Methods: A total of 17 248 eligible participants from a rural Chinese prospective cohort population were included. The same questionnaire interview and anthropometric and laboratory measurements were performed at both baseline (2007)(2008) and follow-up (2013-2014). Participants were classified according to baseline FPG and diabetic status by sex. Restricted cubic splines and Cox proportional-hazards regression models, estimating hazard ratio (HR) and 95% confidence interval (CI), were used to assess the FPG-mortality relation. Results: During the 6-year follow-up, 618 men and 489 women died. The FPGmortality relation was J shaped for both sexes. For men, risk of all-cause and noncardiovascular disease (CVD)/noncancer mortality was greater with low fasting glucose (LFG) than with normal fasting glucose (adjusted HR [aHR] 1.60; 95% CI, 1.05-2.43; and aHR 2.16; 95% CI, 1.15-4.05). Men with diabetes mellitus (DM) showed increased risk of all-cause (aHR 2.04; 95% CI, 1.60-2.60), CVD (aHR 1.98; 95% CI, 1.36-2.89), and non-CVD/noncancer mortality (aHR 2.62; 95% CI, 1.76-3.91). Men with impaired fasting glucose (IFG) had borderline risk of CVD mortality (aHR 1.34; 95% CI, 1.00-1.79). Women with LFG had increased risk of non-CVD/ noncancer mortality (aHR 2.27; 95% CI, 1.04-4.95), and women with DM had

In total, 29 compounds from sweet wormwood ( Artemisia annua L.) oil were identified using gas chromatography–mass spectrometry. The five active components were d -camphor, linalool, cineole, α-terpineol, and l (−)-borneol. The effectiveness of A. annua oil, as well as d -camphor, linalool, cineole, α-terpineol, and l (−)-borneol, as fumigants, contact insecticides, and repellents, were tested on the red imported fire ant Solenopsis invicta Buren. The results indicated that A. annua oil has no significant topical toxicity; however, the spray contact test revealed that it has strong insecticidal activity and the inhibitory effect is stronger during closed exposure than during open exposure. In the fumigant test, cineole and d -camphor exhibited strong fumigant toxicity on minor and major S. invicta workers. They also caused 100% mortality at 5, 3, 2, and 1 mg/centrifuge tube but not at 0.5 mg/centrifuge tube. The mortality rates of linalool, α-terpineol, and l (−)-borneol exceeded 80% at 5, 3, and 2 mg/centrifuge tube. In the repellent test, cineole and d -camphor showed significant repellency at 100, 10, and 1 mg/kg. However, linalool, α-terpineol, and l (−)-borneol significantly facilitated digging at 10 and 1 mg/kg.

To clarify the types, number, and distribution of sensilla on the head of the fifth instar Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) larvae and identify the main sensilla of azadirachtin acting on larvae, scanning electron microscopy was used to study the morphology of the head and sensilla on the mouthparts. The four sensilla—sensillum basiconicum, sensillum chaeticum, sensillum styloconicum, and sensillum trichodeum—on the head of the fifth instar larvae were treated with 0, 0.1, 0.5, 1, 2, and 4 mg/kg azadirachtin by a microdrop method. The larvae showed an obvious antifeeding effect with azadirachtin. And higher the concentration of azadirachtin, the more obvious the phenomenon of antifeeding activity. The sensillum styloconicum and the sensillum trichodeum were the main sensilla for azadirachtin. When 1 mg/kg azadirachtin was used to treat sensillum styloconicum and sensillum basiconicum, the fifth instar larvae of S. litura showed obvious antifeedant activity and the cumulative feed intake for 24 hr was no more than 30% of the leaf area. Quantitative reverse‐transcription polymerase chain reaction verified the expression patterns of some Grs, indicating that Grst43a was upregulated by 1.3‐ and 3.9‐fold, Gor24 was upregulated by 2.5‐ and 3.3‐fold, Gr5a was downregulated by 0.6‐fold and upregulated by 2.0‐fold, and Gr28a was downregulated by 0.8‐fold and upregulated by 3.6‐fold upon treatment with 0.5 mg/kg and 1 mg/kg azadirachtin in 24 hr. Gr genes participated in the identification of bitterness and we speculated that Gr genes may indirectly lead to the occurrence of antifeeding behavior.

Plant essential oils from eight plant species were tested for their insecticidal activities against the red imported fire ant, Solenopsis invcita, by using a fumigation bioassay. This study reveals that the mortalities after treatment of the workers of red imported fire ants varied according to the classification of workers, oil type, dosage, and exposure time. Among the essential oils tested, strong insecticidal activity was observed with the essential oils of camphor (Cinnamomum camphora), artemisia annua (Artemisia annua), eucalyptus (Eucalyptus globulus), mugwort (Artemisia argyi), and wintergreen (Ilex chinensis). Ant mortalities from chrysanthemum oil (Dendranthema indicum), turpentine oil (Pinus massoniana), and forsythia oil (Forsythia suspense) treatments were significantly lower than those from the previously mentioned five essential oil treatments. This study showed that camphor, artemisia annua, eucalyptus, mugwort, and wintergreen oils may have potential to be used as substitutes for chemical insecticides.