title: Dynamics of phoxim residues in green onion and soil as influenced by arbuscular mycorrhizal fungi.
abstract: Organophosphorus pesticides in crops and soil pose a serious threat to public health and environment. Arbuscular mycorrhizal (AM) fungi may make a contribution to organophosphate degradation in soil and consequently decrease chemical residues in crops. A pot culture experiment was conducted to investigate the influences of Glomus caledonium 90036 and Acaulospora mellea ZZ on the dynamics of phoxim residues in green onion (Allium fistulosum L.) and soil at different harvest dates after phoxim application. Results show that mycorrhizal colonization rates of inoculated plants were higher than 70%. Shoot and root fresh weights did not vary with harvest dates but increased significantly in AM treatments. Phoxim residues in plants and soil decreased gradually with harvest dates, and markedly reduced in AM treatments. Kinetic analysis indicated that phoxim degradation in soil followed a first-order kinetic model. AM inoculation accelerated the degradation process and reduced the half-life. G. caledonium 90036 generally produced more pronounced effects than A. mellea ZZ on both the plant growth and phoxim residues in plants and soil. Our results indicate a promising potential of AM fungi for the control of organophosphate residues in vegetables, as well as for the phytoremediation of organophosphorus pesticide-contaminated soil.
authors.affiliation: Agricultural College, Henan University of Science and Technology, 70# Tianjin Road, Jianxi District, Luoyang, Henan Province 471003, PR China. wfy1975@163.com
authors.forename: Fa Yuan
authors.initials: FY
authors.lastname: Wang
authors.forename: Zhao Yong
authors.initials: ZY
authors.lastname: Shi
authors.forename: Rui Jian
authors.initials: RJ
authors.lastname: Tong
authors.forename: Xiao Feng
authors.initials: XF
authors.lastname: Xu
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D006207:Half-Life; D007306:Insecticides / Q000737:chemistry*; D007700:Kinetics; D038821:Mycorrhizae / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019697:Onions / Q000737:chemistry*; D009946:Organothiophosphorus Compounds / Q000737:chemistry*; D010573:Pesticide Residues / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D014675:Vegetables / Q000737:chemistry
chemical_list: D007306:Insecticides; D009946:Organothiophosphorus Compounds; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; C003135:phoxim