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Abstract: BACKGROUND: The use of thelytokous Wolbachia‐infected Trichogramma (parasitic wasps) has long been considered as a way to enhance the efficacy of biocontrol. However, Wolbachia can affect the host physiology. We compared decision‐making between bisexual and thelytokous Wolbachia‐infected lines of Trichogramma dendrolimi Matsumura regarding behavior toward fresh and old eggs of Corcyra cephalonica at 25 ± 1 °C and 70 ± 5% relative humidity. RESULTS: The behavioral patterns and sequences of the two lines were basically the same. The durations of various behavioral patterns and values of fitness indicators of the bisexual line on fresh eggs were generally significantly shorter and better, respectively, than on old eggs, whereas the thelytokous line behaved similarly toward the two types of eggs, and differences in most fitness indicators between fresh and old eggs were not significant. On fresh eggs, the durations of various behaviors in the bisexual line were generally significantly shorter than in the thelytokous line and the fitness indicators were generally significantly better. CONCLUSION: Wolbachia affected the fitness of T. dendrolimi negatively. The potential of the thelytokous line as a biocontrol agent would not be as good as that of the bisexual line when decision‐making only is considered. Therefore, further evaluations need to be carried out before the thelytokous line can be used in practical biocontrol. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

To understand the short-term response of soil CH4 flux to different precipitation events in a winter wheat field on the Loess Plateau, we conducted precipitation simulation experiments during winter wheat jointing stage and summer fallow period to measure the soil CH4 flux in 0 to 72 h after precipitation simulation of 1 to 32 mm. Results showed that CH4 flux during 0 to 72 h fluctuated at 1 to 8 mm of precipitation application and peaked at 16 and 32 mm. Cumulative CH4 flux after 72 h of precipitation (CH4-C) increased linearly with the precipitation amount (P) (wheat jointing stage: CH4-C=2.45P-6.09, R2=0.92, P<0.01; summer fallow: CH4-C=2.43P-4.73, R2=0.91, P<0.01). Statistical analysis showed that CH4 flux was also correlated with soil water content and microbial biomass carbon but not with soil temperature. In the long run, small precipitation events (1-8 mm) could enhance the intensity of soil CH4 sink and such promoting effect would be weakened with further increase in precipitation amount. However, large precipitation events (≥16 mm) could change the soil function from CH4 sink to source by stimulating the activity of soil methanogens during short-term periods. [ABSTRACT FROM AUTHOR]

Alpinia oxyphylla, a traditional herb, is widely used for its neuroprotective, antioxidant and memory-improving effects. However, the neuroprotective mechanisms of action of its active ingredients are unclear. In this study, we investigated the neuroprotective effects of various organic extracts of Alpinia oxyphylla on PC12 cells exposed to hydrogen peroxide-induced oxidative injury in vitro. Alpinia oxyphylla was extracted three times with 95% ethanol (representing extracts 1-3). The third 95% ethanol extract was dried and resuspended in water, and then extracted successively with petroleum ether, ethyl acetate and n-butanol (representing extracts 4-6). The cell counting kit-8 assay and microscopy were used to evaluate cell viability and observe the morphology of PC12 cells. The protective effect of the three ethanol extracts (at tested concentrations of 50, 100 and 200 µg/mL) against cytotoxicity to PC12 cells increased in a concentration-dependent manner. The ethyl acetate, petroleum ether and n-butanol extracts (each tested at 100, 150 and 200 μg/mL) had neuroprotective effects as well. The optimum effective concentration ranged from 50-200 μg/mL, and the protective effect of the ethyl acetate extract was comparatively robust. These results demonstrate that organic extracts of Alpinia oxyphylla protect PC12 cells against apoptosis induced by hydrogen peroxide. Our findings should help identify the bioactive neuroprotective components in Alpinia oxyphylla., Competing Interests: None

Intersex is an intermediate stage of sexual differentiation in insects. Determining intersex morphology and the cause of its production will aid in the understanding of the mechanism of sexual differentiation in insects. In this paper, Wolbachia -infected Trichogramma pretiosum ( T. preW + ) that shows thelytokous parthenogenesis were used as subjects. In order to determine the causes of the T. preW + intersex and the influence of parental generation temperature on gradual changes in secondary masculinization in intersex offspring, we examined the occurrence of intersex offspring (F 1 and F 2 generation) after the parental generations were treated with high temperature (27, 29, 31, and 33 °C) and described the external morphology of the intersexes. The results showed that the T. preW + parental generation temperature is positively correlated with the probability of intersex offspring. The probability of F 1 intersex is significantly higher than that of F 2 intersex in different high temperature. The degree of secondary masculinization in T. preW + intersexes increases as parental generation temperature increases. In addition, our study first identified 11 intersex types in T. preW + and found that the primary and secondary sexual characteristics showed a regular distribution. We also found that the D type and H type of intersex have the highest frequency of appearance. The external genitalia of most intersexes were female, and only three intersex types have male external genitalia. Conclusions were ultimately obtained: Wolbachia is a direct factor that causes the occurrence of intersexes, while high temperature is an indirect factor that determines the external morphology of intersexes. The effects of high temperature on T. preW + intersexes is passed through the parental generation to offspring, and this maternal effect weakens as the number of generations increases. In T. preW + intersex individuals, most exhibit female primary sexual characteristics, and secondary sexual characteristics exhibit signs of masculinization., Competing Interests: The authors declare that they have no competing interests.

To understand the short-term response of soil CH4 flux to different precipitation events in a winter wheat field on the Loess Plateau, we conducted precipitation simulation experiments during winter wheat jointing stage and summer fallow period to measure the soil CH4 flux in 0 to 72 h after precipitation simulation of 1 to 32 mm. Results showed that CH4 flux during 0 to 72 h fluctuated at 1 to 8 mm of precipitation application and peaked at 16 and 32 mm. Cumulative CH4 flux after 72 h of precipitation (CH4-C) increased linearly with the precipitation amount (P) (wheat jointing stage: CH-C=2.45P-6.09, R2=0.92, P<0.01; summer fallow: CH-C=2.43P-4.73, R2 = 0.91, P<0.01). Statistical analysis showed that CH4 flux was also correlated with soil water content and microbial biomass carbon but not with soil temperature. In the long run, small precipitation events (1-8 mm) could enhance the intensity of soil CH4 sink and such promoting effect would be weakened with further increase in precipitation amount. However, large precipitation events (≥16 mm) could change the soil function from CH4 sink to source by stimulating the activity of soil methanogens during short-term periods.