Investigation On Occurrence Dynamics Of Pests Injuring The Dehydrated Vegetable Materials And Analysis Of Pesticide Residue In Finished Products In Hexi Area, Gansu

Through the field investigation and experiment analysis, the dominant kinds of plant diseases and insect pests and its development trends, preventing and controlling technology have been defined initially in the Hexi area (Jiuquan, Zhangye, Wuwei three city) of Gansu, where fresh /dehydrated vegetables (mainly frozen and air dried) are produced and processed for export.. and residue of pesticides in the dehydrated vegetables has inspected. The results indicate that total 8 kinds of plant diseases and insect pests, including 3 plant diseases, 4 insect pests and 1 physiological disease are found for hot pepper;total 11,3 plant diseases, 7 insect pests and 1 physiological disease for tomato;total 4, 2 plant diseases, 2 insect pests for onion;total 6, 2 plant diseases, 4 insect pests for Kidney bean;total 9, 2 plant diseases, 7 insect pests for cauliflower;total 3, 2 plant diseases, 1 insect pests for carrot. But generally it is impossible that those plant diseases and insect pests take place widely and greatly because of the very badly climatic conditions in the area. Most of the pests are less in taking place amount and produce relatively light damage to vegetables. Some species such as Phytophthora capsici Leon. , Leveillula taurica (Lev.) Arn., Peronospora schleidemi Ung., Hylemyia antiqua (Meigen), Pieris rapae Linnaeus, Plutella xylostella Linnaeus, Myzus persicae (Sulzer) take place seriously in part of places or fields and cause serious threat to vegetables. Thrie occurance laws and control methods on those advantage kinds of pests were also investigated in this paper.Pesticide residues of samples including ketchup, dehydrate blue and green hot red pepper, dehydrate onion, dehydrate carrot, dehydrate tomato, dehydrate kidney bean , dehydrate cauliflower, were analyzed according to the national method of testing for pesticide residues from 8 export processing enterprises. The results showed that residues of 16 pesticides, including Chlorothalonil, Metalaxyl, Thiophanate-methyl, Fenpropathrin, Cypermethrin, Fenvalerate, Deltamethrin, Bifenthrin, Cyhalothrin, Omethoate, Dimethoate, Malathion, Phorate, Tsumacide, Pirimicarb, Hexythiazox, Dursban, Monocrotophos, in all samples completely meet with the standard of European Union except metalaxyl in ketchup and national standard on environment-friendly vegetables.On the basis of the systematic investigation and primary analysis, a set of preventing and controlling techniques on main plant diseases and insect pests was proposed.