title: Phoxim Microcapsules Prepared with Polyurea and Urea-Formaldehyde Resins Differ in Photostability and Insecticidal Activity.
abstract: The application of pesticide microcapsules (MCs) in agriculture is becoming more and more popular. In this study, the effects of different wall materials on the stomach toxicity, contact toxicity, length of efficacy, and photolysis characteristics of pesticide microcapsules were investigated. The results showed that microencapsulation reduced the stomach and contact toxicities of phoxim and prolonged the efficacy of this light-sensitive chemical in the greenhouse test. Neither of the degradation curves for microencapsulated phoxim under ultraviolet light fit a first-order model, although the emulsifiable concentrate (EC) degradation curve fit it well. The phoxim-loaded polyurea microcapsules (PUA-MCs) showed significantly increased UV-resistance ability, stomach toxicity, and contact toxicity compared with the phoxim-loaded urea-formaldehyde microcapsules (UF-MCs). These experiments indicated that it is crucial to select the appropriate wall materials for pesticide microcapsules on the basis of application sites and physicochemical properties of pesticide active ingredients.
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Da-xia
authors.initials: DX
authors.lastname: Zhang
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Bei-xing
authors.initials: BX
authors.lastname: Li
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Xian-peng
authors.initials: XP
authors.lastname: Zhang
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Zheng-qun
authors.initials: ZQ
authors.lastname: Zhang
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Wei-chang
authors.initials: WC
authors.lastname: Wang
authors.affiliation: Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection; ‡Research Center of Pesticide Environmental Toxicology; #Key Laboratory of Pesticide Toxicology & Application Technique; and ⊥College of Horticultural Science and Engineering, Shandong Agricultural University , Tai'an, Shandong 271018, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
mesh_terms: D000818:Animals; D002214:Capsules / Q000737:chemistry; D004339:Drug Compounding / Q000295:instrumentation / Q000379:methods*; D005557:Formaldehyde / Q000737:chemistry; D007306:Insecticides / Q000737:chemistry* / Q000633:toxicity*; D009036:Moths / Q000187:drug effects; D009946:Organothiophosphorus Compounds / Q000737:chemistry*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry; D014466:Ultraviolet Rays; D014508:Urea / Q000737:chemistry
chemical_list: D002214:Capsules; D007306:Insecticides; D009946:Organothiophosphorus Compounds; D011108:Polymers; D005557:Formaldehyde; C045786:polyurea; C003135:phoxim; D014508:Urea
keywords: contact toxicity; microcapsule; phoxim; polyurea; stomach toxicity; urea−formaldehyde resin