Effects of manganese on the catalytic performance of CuCo catalysts for direct conversion of CO/CO2 to higher alcohols.

The catalytic conversion of CO or CO/CO2 mixtures to higher alcohols (HAs) using hydrogenation reactions remains challenging in C1 chemistry and also one of the most promising reactions for the utilization of non-petroleum resources. Here, the experiment and characterization tests of CuCoMn/Al2O3 show that copper is much more dispersed on γ-Al2O3 than cobalt, and the interaction between cobalt and Mn metals is stronger. And, mixed cobalt-manganese oxides are formed in the calcined catalyst, promoting the formation of higher alcohols. Under the optimum conditions, the catalyst demonstrated a total alcohol selectivity of 44.6%, and the fraction of higher alcohols reached up to 85.3% among the total alcohol products, which is superior to the classical modified CuCo-based catalysts. And in the gas mixture reaction with a CO : CO2 ratio of 8 : 2, the conversion rate of the catalyst to CO and CO2 reached 34.8% and 27.3%, respectively, and the selectivity (C1+ slate 1-alcohol) was 53.2%.

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.

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.

Comparative transcriptome analysis of differentially expressed genes in Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae) at different acute stress temperatures.

The gnat, Bradysia odoriphaga Yang et Zhang, is an important underground pest in Asia. B. odoriphaga differ in heat and cold tolerance and exhibit quite different developmental strategies. To understand the underlying mechanisms, we sequenced and compared the transcriptome of B. odoriphaga under 40 °C (a stressful high temperature), 25 °C, and 4 °C (a stressful low temperature) for 1 h. We found that metabolism- and ribosome-related genes were modulated. In high temperature (40 °C), heat shock protein (HSP) genes, detoxication genes, metabolism genes, protein turnover genes, and stress signal transduction genes were differentially expressed. In low temperature (4 °C), genes related with heat shock protein (HSP) and detoxication were differentially expressed. Our study increases our understanding of the complex molecular mechanisms involved in the responses of B. odoriphaga to acute temperature stress and provides a potential strategy for pest management.

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.

Sphaerisporangium corydalis sp. nov., isolated from the root of Corydalis yanhusuo L.

Two Gram-stain positive, aerobic actinomycete strains, designated NEAU-YHS12 and NEAU-YHS15(T), were isolated from the root of Corydalis yanhusuo L. collected from Wuchang, Heilongjiang Province, northeast China. Phylogenetic analysis of 16S rRNA gene sequences showed that the two strains are closely related to one another (99.8 % similarity), and had the closest relationship with Sphaerisporangium cinnabarinum JCM 3291(T) (98.7, 98.6 %), Sphaerisporangium flaviroseum YIM 48771(T) (98.6, 98.6 %), Sphaerisporangium melleum JCM 13064(T) (98.5, 98.4 %) and Sphaerisporangium dianthi NEAU-CY18(T) (98.4, 98.4 %). DNA-DNA hybridization value between strains NEAU-YHS12 and NEAU-YHS15(T) was 82 ± 1.4 %, and the values between the two strains and the closely related type strains were well below 70 %. The two strains also shared a number of phenotypic characteristics that were distinct from the closely related species. Both strains were observed to contain MK-9(H6), MK-9(H4) and MK-9(H2) as the detected menaquinones. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid. The phospholipid profiles were found to contain diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, phosphoglycolipid, and an unidentified phospholipid. The major fatty acids were identified as iso-C16:0, C17:1 ω7c, C18:0 and iso-C15:0. On the basis of the genetic and phenotypic properties, it is proposed that strains NEAU-YHS15(T) and NEAU-YHS12 be classified as representatives of a novel species of the genus Sphaerisporangium, for which the name Sphaerisporangium corydalis sp. nov is proposed. The type strain is NEAU-YHS15(T) (CGMCC 4.7148(T) = DSM46732(T)).

Transmission of Tomato Yellow Leaf Curl Virus by Bemisia tabaci as Affected by Whitefly Sex and Biotype.

Bemisia tabaci is a serious pest of vegetables and other crops worldwide. The most damaging and predominant B. tabaci biotypes are B and Q, and both are vectors of tomato yellow leaf curl virus (TYLCV). Previous research has shown that Q outperforms B in many respects but comparative research is lacking on the ability of B and Q to transmit viruses. In the present study, we tested the hypothesis that B and Q differ in their ability to transmit TYLCV and that this difference helps explain TYLCV outbreaks. We compared the acquisition, retention, and transmission of TYLCV by B and Q females and males. We found that Q females are more efficient than Q males, B females, and B males at TYLCV acquisition and transmission. Although TYLCV acquisition and transmission tended to be greater for B females than B males, the differences were not statistically significant. Based on electrical penetration graphs determination of phloem sap ingestion parameters, females fed better than males, and Q females fed better than Q males, B females, or B males. These results are consistent with the occurrences of TYLCV outbreaks in China, which have been associated with the spread of Q rather than B.