红火蚁Solenopsis invicta是一种严重威胁入侵地生物多样性、农林业生产和公共安全的危险性害虫。目前，红火蚁的防治药剂主要分为毒饵和触杀性粉剂两种类型。毒饵对红火蚁的防控效果虽然较彻底，但是见效慢，一般2周左右才能达到理想的防效。触杀性粉剂见效快，施药后3-5天即可达到理想效果，适合应用于红火蚁的紧急扑灭。为筛选出更多可用作触杀性粉剂的有效成分，本文开展了联苯菊酯和四氟甲醚菊酯对红火蚁的毒力、水平传递毒性及其触杀性粉剂的田间防效研究。研究显示，联苯菊酯和四氟甲醚菊酯对红火蚁工蚁的致死中量LD₅₀分别为3.40 ng/头和1.57 ng/头。20 μg mL^-1联苯菊酯对红火蚁工蚁的击倒中时KT₅₀和95%击倒时间KT₉₅分别为7.179 min和16.611 min。20 μg mL^-1四氟甲醚菊酯对红火蚁工蚁的击倒中时KT₅₀和95%击倒时间KT₉₅分别为1.538 min和2.825 min。联苯菊酯触杀性粉剂和四氟甲醚菊酯触杀性粉剂在蚁群间具有良好的水平传递毒性。0.25、0.50 和1.00% 联苯菊酯触杀性粉剂处理48小时后，第一次继发传递毒性的受药蚁的死亡率（二级死亡率）和第二次继发传递毒性的受药蚁的死亡率（三级死亡率）均超过了80%。0.25、0.50 和1.00% 四氟甲醚菊酯触杀性粉剂处理48小时后，第一次继发传递毒性的受药蚁的死亡率超过了99%，但是第二次继发传递毒性的受药蚁的死亡率则低于20%。野外结果显示，1.00%联苯菊酯触杀性粉剂和1.00%四氟甲醚菊酯触杀性粉剂处理14天后，对红火蚁蚁群的综合防效分别为95.87%和85.70%，防治效果较好。

2022年1月，我们收到来自广东省汕头市的3巢蚂蚁标本，经形态特征和分子鉴定确定为小火蚁。小火蚁被世界自然保护联盟（IUCN）列为最具危害性的100种入侵物种之一，已从其原产地南美洲蔓延到除南极洲以外的每个大陆。对9头工蚁的线粒体基因序列（mtDNA COI）分析发现，它们与来自阿根廷的样本有着密切的遗传关系。本文首次正式记录了小火蚁入侵中国大陆，但它在中国的入侵阶段和发生程度尚不清楚，相关部门应该加强该种入侵蚂蚁的植物检疫、发生分布调查、生物生态学特性研究、监测与防控技术开发等，以积极应对小火蚁对我国社会与生态安全的威胁。

频繁的国际贸易加速了外来物种的入侵。然而，外来物种在入侵后的地理分布以及决定其分布的因素尚缺乏相关数据。本研究分析了中国入侵物种的分布变动趋势及其驱动因素。此外，还对改革开放前、1979年至2001年和中国加入世界贸易组织以来13种主要入侵昆虫在中国的空间分布进行了动态分析，以探讨增加国际贸易对中国入侵物种地理分布的影响。结果表明，入侵物种的丰度由南向北、由东南沿海向内陆逐渐减少。广东省（442种）和云南省（404种）的入侵物种丰度最高。在调查的13种重点入侵昆虫中，3个时期分别出现3种、10种和13种，入侵省份分别为7个、28个和34个。另分析显示，外来害虫主要经新疆、环渤海地区和东南部入侵我国。在所有因子中，进口贸易值是中国入侵物种数量的有力预测因子。进口贸易值和温度是解释除了微生物外的入侵物种丰度异质性空间分布的关键因子。研究结果为进一步开展国际检疫工作和有效控制入侵物种提供了科学依据。

Organophosphate insecticide residues on vegetable, fruit, tea and even grains are primary cause of food poisoning. Organophosphate compounds can cause irreversible inhibition of the activity of acetylcholinesterase and butyrylcholinesterase (BChE, EC 3.1.1.8), which are both candidates for rapid detection of organophosphate pesticides. To develop an easy-tohandle method for detecting organophosphate pesticides using BChE, BChE from human was optimized according to the codon usage bias of Pichia pastoris and successfully expressed in P. pastoris GS115. The codon-optimized cDNA shared 37.3% of the codon identity with the native one. However, the amino acid sequence was identical to that of the native human butyrylcholinesterase gene (hBChE) as published. The ratio of guanine and cytosine in four kinds of bases ((G+C) ratio) was simultaneously increased from 40 to 47%. The recombinant hBChE expression reached a total protein concentration of 292 mg mL–1 with an activity of 14.7 U mL–1, which was purified 3.2×103-fold via nickel affinity chromatography with a yield of 68% and a specific activity of 8.1 U mg–1. Recombinant hBChE was optimally active at pH 7.4 and 50°C and exhibited high activity at a wide pH range (>60% activity at pH 4.0 to 8.0). Moreover, it had a good adaptability to high temperature (>60% activity at both 50 and 60°C up to 60 min) and good stability at 70°C. The enzyme can be activated by Li+, Co+, Zn2+ and ethylene diamine tetraacetic acid (EDTA), but inhibited by Mg2+, Mn2+, Fe2+, Ag+ and Ca2+. Na+ had little effect on its activity. The values of hBChE of the Michaelis constant (Km) and maximum reaction velocity (Vm) were 89.4 mmol L–1 and 1 721 mmol min–1 mg–1, respectively. The bimolecular rate constants (Ki) of the hBChE to four pesticides were similar with that of electric eel AChE (EeAChE) and higher than that of horse BChE (HoBChE). All values of the half maximal inhibitory concentration of a substance (IC50) for hBChE were lower than those for HoBChE, but most IC50 for hBChE were lower than those for EeAChE except dichlorvos. The applicability of the hBChE was further verified by successful detection of organophosphate insecticide residues in six kinds of vegetable samples. Thus, hBChE heterologously over-expressed by P. pastoris would provide a sufficient material for development of a rapid detection method of organophosphate on spot and produce the organophosphate detection kit.

The detection of chemical contaminants is critical to ensure dairy safety. These contaminants include veterinary medicines, antibiotics, pesticides, heavy metals, mycotoxins, and persistent organic pollutants (POPs). Immunoassays have recently been used to detect contaminants in milk because of their simple operation, high speed, and low cost. This article describes the latest developments in the most important component of immunoassays — antibodies, and then reviews the four major substrates used for immunoassays (i.e., microplates, membranes, gels, and chips) as well as their use in the detection of milk contaminants. The paper concludes with prospects for further applications of these immunoassays.

Oryza officinalis is one of the important wild species in the tertiary gene pool of Oryza sativa. It has a number of elite genes for rice breeding in resistance or tolerance. However, breeding barriers are so serious that the gene transfer is much difficult by sexual cross method between O. sativa and O. officinalis. Characteristics of the breeding barriers were systemically studied in this paper. When both the diploid (AA, 2n=2x=24) and autotetraploid (AAAA, 2n=4x=48) cultivated rice were crossed as maternal parents with O. officinalis (CC, 2n=2x=24), none F1 hybrid seeds were obtained. The young hybrid ovaries aborted at 13-16 d after pollinations (DAP). By rescuing hybrid embryos, in vitro F1 plantlets were obtained in 2x×2x combinations with the crossabilities lower than 0.5%. Lower rates of double-fertilization and abnormal development of hybrid embryo and endosperm were mainly observed in both combinations of 2x×2x and 4x×2x. Free endosperm nuclei in hybrid degenerated early at 1 DAP in a large scale. Almost no normal endosperm cells formed at 3 DAP. Development of a lot of embryos ceased at globular- or pear-shaped stage as well as some degenerated gradually. The hybrid plantlets were both male and female sterility. Due to the abnormal development, a diversity of abnormal embryo sacs formed in hybrids, and hybrid pollen grains were typically abortive. It showed that conflicts of genome A and C in hybrid induced abnormal meioses of meiocytes.