Molecular basis and regulatory mechanisms underlying fungal insecticides' resistance to solar ultraviolet irradiation

Resistance to solar ultraviolet (UV) irradiation is crucial for field-persistent control efficacies of fungal formulations against arthropod pests, because their active ingredients are formulated conidia very sensitive to solar UV wavelengths. This review seeks to summarize advances in studies aiming to quantify, understand and improve conidial UV resistance. One focus of studies has been on the many sets of genes that have been revealed in the postgenomic era to contribute to or mediate UV resistance in the insect pathogens serving as main sources of fungal insecticides. Such genetic studies have unveiled the broad basis of UV-resistant molecules including cytosolic solutes, cell wall components, various antioxidant enzymes, and numerous effectors and signaling proteins, that function in developmental, biosynthetic and stress-responsive pathways. Another focus has been on the molecular basis and regulatory mechanisms underlying photorepair of UV-induced DNA lesions and photoreactivation of UV-impaired conidia. Studies have shed light upon a photoprotective mechanism depending on not only one or two photorepair-required photolyases, but also two white collar proteins and other partners that play similar or more important roles in photorepair via interactions with photolyases. Research hotspots are suggested to explore a regulatory network of fungal photoprotection and to improve the development and application strategies of UV-resistant fungal insecticides. © 2021 Society of Chemical Industry.     

氯苯、对硝基酚对土壤生物活性的影响

本文通过对土壤呼吸强度，各微生物生理群的数理以及土壤酶活性的测定，研究了氯苯，对硝基酚对土壤生物活性的影响。实验表明氯苯，对硝基酚对土壤活性的影响是复杂的。氯苯在２００ｍｇ／ｋｇ以下对土壤呼吸强度，细菌放线菌及真菌的数量都有一定的刺激作用；而对氨化细菌硝化细菌以及反硝化细菌则表现出抑制作用；     

东亚小花蝽携带绿僵菌防控西花蓟马和烟粉虱的效果评价

天敌昆虫和生防菌的联合应用对害虫防控具有潜在的增效作用。东亚小花蝽Orius sauteri是目前常用的捕食性天敌之一, 被广泛用于温室蓟马、粉虱等害虫的防治。金龟子绿僵菌Metarhizium anisopliae寄主广泛, 可有效防治多种温室害虫, 且相对安全。为探索东亚小花蝽与金龟子绿僵菌联用的控害效果, 本文在室内和田间条件下研究了二者对烟粉虱Bemisia tabaci和西花蓟马Frankliniella occidentalis的协同控害作用。室内测定结果表明, 绿僵菌孢子悬浮液浓度不大于5×107孢子/mL时, 不会对东亚小花蝽5龄若虫的存活和羽化造成负面影响。室内与温室笼罩条件下, 东亚小花蝽携带绿僵菌的处理能够降低辣椒上的西花蓟马和烟粉虱发生量, 表明东亚小花蝽携带绿僵菌可提高对西花蓟马和烟粉虱的防治效果, 证明了天敌昆虫和生防菌联合应用的可行性, 为生物防治方式多元化应用与推广提供了实践指导。     

基于16S rRNA高通量测序的野生和养殖多鳞白甲鱼肠道微生物群落组成研究

为研究多鳞白甲鱼肠道微生物菌群组成及其多样性,采用16S rRNA高通量测序对野生多鳞白甲鱼以及养殖成年健康多鳞白甲鱼肠道内容物进行微生物测序及信息分析.结果表明:不同环境多鳞白甲鱼肠道内容物样品间OTU个数具有一定差别.多鳞白甲鱼肠道菌群主要包括:变形菌门(Proteobacteria)、梭杆菌门(Fusobacte...