在中国应用垂直波束雷达监测褐飞虱和其他水稻害虫迁飞的可行性

近年来,可用于昆虫迁飞研究且可自动运行的垂直波束雷达(vertical-looking radar,VLR)的发展使得对迁飞性害虫的周年长期自动监测成为可能。本文提供了我们对能否将这种雷达应用于中国的褐飞虱和其他水稻害虫的监测与预测体系以改善其综合治理的可行性研究结果。以往的研究已经表明,这些害虫一般在300—2000m高度迁飞;而我们根据褐飞虱的雷达和射有效截面的计算结果表明,目前使用的3．2cm波长的VLR对褐飞虱个体目标的最大可检测高度仅约240m;虽然建造一部8．8mm波长的VLR即可覆盖褐飞虱迁飞高度的绝大部分,但其造价和维护费用均过于昂贵。为此,一个更可行的解决方案是,以3．2cm波长的VLR作为包括大多数水稻害虫在内的个体较大的迁飞性害虫的监测工具。     

Hybridization patterns between two marine snails,Littorina fabalis and L. obtusata

Characterizing the patterns of hybridization between closely related species is crucial to understand the role of gene flow in speciation. In particular, systems comprising multiple contacts between sister species offer an outstanding opportunity to investigate how reproductive isolation varies with environmental conditions, demography and geographic contexts of divergence. The flat periwinkles, Littorina obtusata and L. fabalis (Gastropoda), are two intertidal sister species with marked ecological differences compatible with late stages of speciation. Although hybridization between the two was previously suggested, its extent across the Atlantic shores of Europe remained largely unknown. Here, we combined genetic (microsatellites and mtDNA) and morphological data (shell and male genital morphology) from multiple populations of flat periwinkles in north‐western Iberia to assess the extent of current and past hybridization between L. obtusata and L. fabalis under two contrasting geographic settings of divergence (sympatry and allopatry). Hybridization signatures based on both mtDNA and microsatellites were stronger in sympatric sites, although evidence for recent extensive admixture was found in a single location. Misidentification of individuals into species based on shell morphology was higher in sympatric than in allopatric sites. However, despite hybridization, species distinctiveness based on this phenotypic trait together with male genital morphology remained relatively high. The observed variation in the extent of hybridization among locations provides a rare opportunity for future studies on the consequences of different levels of gene flow for reinforcement, thus informing about the mechanisms underlying the completion of speciation.     

In vitro culture of Lippia dulcis (Trev.): light intensity and wavelength effects on growth,antioxidant defense,and volatile compound production

In Vitro Cellular & Developmental Biology - Plant - Plants of the Verbenaceae family are well known for having constituents with important bioactive properties. The objective of this study was...     

Jackson trap efficiency capturing Bactrocera dorsalis and Zeugodacus cucurbitae with male lures with and without insecticides

Jackson traps baited with male lures with or without insecticides are essential components of surveillance and monitoring programmes against pest tephritid fruit flies. The ability of a trap to capture a fly that enters, sometimes termed ‘trap efficiency’, is dependent on many factors including the trap/lure/toxicant combination. We tested the effects of three important components of Jackson traps on efficiency of capture of two important fruit fly species, using the ‘standard’ (i.e. as they are used in the state-wide surveillance programme in California) and alternative setups: Insecticide (Naled, DDVP or None), type of adhesive on the sticky panel (Seabright Laboratories Stickem Special Regular or Stickem Special HiTack) and use of a single or combination male lure (Methyl eugenol and/or cuelure). Experiments were conducted in large outdoor carousel olfactometers with known numbers of Bactrocera dorsalis and Zeugodacus cucurbitae and by trapping wild populations of the same two species. Lures were aged out to eight weeks to develop a comprehensive dataset on trap efficiency of the various combinations. Results indicate that the current liquid lure/naled combinations on cotton wicks used in California for surveillance of these flies can be effectively replaced by plastic polymer plugs for the lure and pre-packaged DDVP strips with no loss of trap efficiency for eight weeks of use or longer. The ‘high tack’ adhesive showed no advantage over the current standard against these flies, and both have low efficiency when used without an insecticide in the trap. Combination lure + DDVP varied when compared to the current standard liquid lure + naled: Olfactometer assays showed similar efficiency between them for B. dorsalis, but higher efficiency for the wafer against Z. cucurbitae. Field result showed similar or slightly higher performance of the wafer compared with the standard for B. dorsalis, but a much lower catch of Z. cucurbitae.     

NLRP3 activation contributes to endothelin-1-induced erectile dysfunction

In the present study, we hypothesized that endothelin (ET) receptors (ET_A and ET_B) stimulation, through increased calcium and ROS formation, leads to Nucleotide Oligomerization Domain-Like Receptor Family, Pyrin Domain Containing 3 (NLRP3) activation. Intracavernosal pressure (ICP/MAP) was measured in C57BL/6 (WT) mice. Functional and immunoblotting assays were performed in corpora cavernosa (CC) strips from WT, NLRP3^−/− and caspase^−/− mice in the presence of ET-1 (100 nM) and vehicle, MCC950, tiron, BAPTA AM, BQ123, or BQ788. ET-1 reduced the ICP/MAP in WT mice, and MCC950 prevented the ET-1 effect. ET-1 decreased CC ACh-, sodium nitroprusside (SNP)-induced relaxation, and increased caspase-1 expression. BQ123 an ET_A receptor antagonist reversed the effect. The ET_B receptor antagonist BQ788 also reversed ET-1 inhibition of ACh and SNP relaxation. Additionally, tiron, BAPTA AM, and NLRP3 genetic deletion prevented the ET-1-induced loss of ACh and SNP relaxation. Moreover, BQ123 diminished CC caspase-1 expression, while BQ788 increased caspase-1 and IL-1β levels in a concentration-dependent manner (100 nM–10 μM). Furthermore, tiron and BAPTA AM prevented ET-1-induced increase in caspase-1. In addition, BAPTA AM blocked ET-1-induced ROS generation. In conclusion, ET-1-induced erectile dysfunction depends on ET_A- and ET_B-mediated activation of NLRP3 in mouse CC via Ca²⁺-dependent ROS generation.