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C2‐functionalized pyrimidine derivative is a family of important nitrogen heterocyclic compounds due to their unique structure and multiple reaction sites. In this work, a novel method for the synthesis of C2‐functionalized pyrimidine derivatives through phenylalkynes and pyrimidine disulfides under ambient conditions is proposed. The reaction can be triggered by adding catalytic amounts of cesium fluoride, which is characterized by free‐catalyst and special activator. Importantly, this reaction has good compatibility with substrates substituted by electron‐donating and electron‐withdrawing groups at C4. Density functional theory (DFT) calculations also indicates that the production of C2‐functionalized pyrimidine derivatives is more favourable. [ABSTRACT FROM AUTHOR]

Simple Summary: In this article, we studied the interactions between the invasive thrips pest Frankliniella occidentalis (WFT) and a native thrips Frankliniella intonsa (IFT) in China, where they co-exist on crop plants and WFT seems to outcompete IFT. In laboratory bioassays we focused on the reproductive mode of the thrips (sexual or parthenogenic), and the presence of a sugar source (honey or flowers), both variables that change over time during pest colonisation of a crop. Our results suggest that in the early stages of F. occidentalis invasion, the provision of honey (flowering) promotes this pest's population development. This research will inform effective strategies for the management of F. occidentalis invasion and help reduce subsequent crop damages. Background: Flower thrips (Frankliniella intonsa, IFT) and west flower thrips (Frankliniella occidentalis, WFT) are often found together on the host plant in China. WFT is an important invasive species that seems to outcompete the native IFT. In order to clarify the interspecific competitions between the two thrips, this study measured the population development of IFT and WFT under sexual and parthenogenetic reproductive modes on two hosts (fresh lentil bean pods with/without honey and pepper plants at seedling/flowering stages) in the laboratory. Results: When reared on fresh lentil bean pods (with/without honey), WFT population size was lower in mixed species populations compared to single species populations but the presence of WFT had nor negative effect on IFT population size. These results were dependent of the reproductive mode. When honey was supplied, the ratio of female-to-male in the progeny of WFT produced under sexual reproductive mode increased significantly in the presence of IFT. On pepper seedlings, mixed populations were more favorable to the population development of IFT at the seedling stage, but more favorable to WFT at the flowering stage. Conclusions: In the early stage of WFT invasion and colonization, the emergence of flowering and honey (nectar) sources may have a positive effect on the population development of WFT. [ABSTRACT FROM AUTHOR]

Insect neuropeptides play an important role in regulating physiological functions such as growth, development, behavior and reproduction. We identified temperature‐sensitive neuropeptides and receptor genes of the cotton whitefly, Bemisia tabaci. We identified 38 neuropeptide precursor genes and 35 neuropeptide receptors and constructed a phylogenetic tree using additional data from other insects. As temperature adaptability enables B. tabaci to colonize a diversity of habitats, we performed quantitative polymerase chain reaction with two temperature stresses (low = 4 °C and high = 40 °C) to screen for temperature‐sensitive neuropeptides. We found many neuropeptides and receptors that may be involved in the temperature adaptability of B. tabaci. This study is the first to identify B. tabaci neuropeptides and their receptors, and it will help to reveal the roles of neuropeptides in temperature adaptation of B. tabaci. [ABSTRACT FROM AUTHOR]

To explore the association between single nucleotide polymorphisms (SNPs) in the promoter region of the inner centromere protein (INCENP) gene and bovine semen quality, the haplotypes in 250 Chinese Holstein bulls were detected using PCR-RFLP method in this study. Two SNPs (g.-556 G>T, rs 136823901 and g.-692 C>T, rs 211010999) and three haplotypes (CG, TT, TG) were identified in the promoter region of INCENP. The genotype frequency and allele frequency of these two SNPs as well as the correlation between different SNP haplotype combinations and bovine semen quality were then analyzed. Our results showed that fresh sperm motility of the GT genotype was significantly higher than that of the GG genotype (P<0.05) at the SNP site g.-556 G>T, while fresh and frozen-thawed sperm motilities of the haplotype combinations H1H1(CCGG), H1H3(CTGT), H2H3(TTGT) and H3H3(TTTT) were significantly higher than that of H1H2 (P<0.05). To further study the possible mechanisms by which g.-556 G>T and g.-692 C>T affect semen quality, three haplotype plasmids were respectively transfected into MLTC-1 cells. The TG haplotype demonstrated the highest luciferase activity, suggesting that g.-556 G>T and g.-692 C>T are functional mutations which could regulate INCENP gene expression by affecting promoter activity and thus affect semen quality.