title: Slow Release of Plant Volatiles Using Sol-Gel Dispensers.
abstract: The black citrus aphid, also known as the tea aphid, (Toxoptera aurantii Boyer) attacks economically important crops, including tea (Camellia sinensis (L.) O. Kuntze). In the current study, silica sol-gel formulations were screened to find one that could carry and release C. sinensis plant volatiles to lure black citrus aphids in a greenhouse. The common plant volatile trans-2-hexen-1-al was used as a model molecule to screen for suitable sol-gel formulations. A zNose (Electronic Sensor Technology, Newbury Park, CA) transportable gas chromatograph was used to continuously monitor the volatile emissions. A sol-gel formulation containing tetramethyl orthosilicate and methyltrimethoxysilane in an 8:2 (vol:vol) ratio was selected to develop a slow-release dispenser. The half-life of trans-2-hexen-1-al in the sol-gel dispenser increased slightly with the volume of this compound in the dispenser. Ten different volatiles were tested in the sol-gel dispenser. Alcohols of 6-10 carbons had the longest half-lives (3.01-3.77 d), while esters of 6-12 carbons had the shortest (1.53-2.28 d). Release of these volatiles from the dispensers could not be detected by the zNose after 16 d (cis-3-hexenyl acetate) to 26 d (3,7-dimethylocta-1,6-dien-3-ol). In greenhouse experiments, trans-2-hexen-1-al and cis-3-hexen-1-ol released from the sol-gel dispensers attracted aphids for ≍17 d, and release of these volatiles could not be detected by the zNose after ≍24 d. The sol-gel dispensers performed adequately for the slow release of plant volatiles to trap aphids in the greenhouse.
authors.affiliation: Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, 9 MeiLing South Road, Xihu District, Hangzhou 310008, China.
authors.forename: L
authors.initials: L
authors.lastname: Bian
authors.affiliation: Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, 9 MeiLing South Road, Xihu District, Hangzhou 310008, China.
authors.forename: X L
authors.initials: XL
authors.lastname: Sun
authors.affiliation: Ministry of Agriculture Key Laboratory for Pesticide Residue Detection, Institute of Quality and Standard for Agricultural Products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
authors.forename: X M
authors.initials: XM
authors.lastname: Cai
authors.affiliation: Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, 9 MeiLing South Road, Xihu District, Hangzhou 310008, China. zmchen2006@163.com.
authors.forename: Z M
authors.initials: ZM
authors.lastname: Chen
mesh_terms: D000080462:Acyclic Monoterpenes; D000447:Aldehydes; D000818:Animals; D001042:Aphids; D028241:Camellia sinensis / Q000737:chemistry*; D000441:Hexanols; D007300:Insect Control / Q000379:methods*; D039821:Monoterpenes; D055549:Volatile Organic Compounds / Q000008:administration & dosage*
chemical_list: D000080462:Acyclic Monoterpenes; D000447:Aldehydes; D000441:Hexanols; D039821:Monoterpenes; D055549:Volatile Organic Compounds; C051918:3-hexen-1-ol; C051750:2-hexenal; C018584:linalool
keywords: Aphididae; plant volatile; slow release; sol-gel; zNose