The Study On Residual Rule Of Five Pestcides In Industrial Cultivation Of Agaricus Bisporus

Edible fungi are one of the most well-known dish with high nutritional value, delicious taste, low fat and abundant proteins. In recent years, the total annual export of edible fungi in China has exceeded 30 million tons with the output value of up to 200 billion yuan, ranking first in the world. Agaricus Bisporus is an important worldwide edible fungus. The output of the Agaricus Bisporus is about 3 million tons, accounting for 10% of the total edible fungus production, approximately. However, mushroom diseases and insect pests are easy to grow under the production environment of Agaricus Bisporus due to suitable temperature and humidity especially in industrial production. Farmers usually use pesticides to prevent and control the disease and insect pests for economic benefits. As a result, a variety of pesticide residues were detected in Agaricus bisporus, its compost and covering soil in several areas in the safety investigation of edible fungi. To our disappointment, we are scarce of registration pesticides and their standards of pesticides, which causes potential safety riskss to consumer in Agaricus bisporus.In this application, the uses of pesticides during the whole process of Agaricus Bisporus production in Shanghai was investigated firstly to master the main pesticide pollution problems in the cultivation of double spore mushroom. Referring to relevant data and literatures, five pesticides usually applied in covering soil were selected to reveal the dynamic changes of different types and doses of pesticides during Agaricus bisporus cultivation. In later research, acetamiprid was selected to mix with soil and compost separately to compare the residue level of pesticides in different application method.These researches provided data support for the usage of pesticides in edible fungi and technical service for export of mushroom, aimed to guarantee the safety in the process of Agaricus bisporus consumption. The results and conclusions of this study are as following:(1) 13 kinds of pesticides were detected in mushroom fruits, substrate and covering soil during the follow-up survey to some edible fungi co-op in Chongming and Jinshan, Shanghai, including carbendazim, prochlorazd, chlorpyrifos and DDVP which were detected in agaricus bisporus, and the prochlorazd remained up to 0.64 mg/kg. 10 kinds of pesticides were detected in substrate, in which the prochlorazd remained up to 20.79 mg/kg. 9 kinds of pesticides have been detected in covering soil, in which prochlorazd and carbendazim remained up to 13.26 and 5.89 mg/kg, respectively. The result showed that during the production of Agaricus bisporus pesticides were obviously remained in covering soil, substrate and mushroom.(2) Detection methods of Carbendazim, prochloraz, acetamiprid, λ-Cyhalothri n and cyromazine in three substractes were all well established. Satisfactory linea rities(R2≥0.991) and recoveries were obtained. The recoveries of Carbendazim, prochloraz,acetamiprid,λ-Cyhalothrin and cyromazine were 75.9~94.2%, 78.0~101.8%, 81.1~96.8%, 75.3~100.4% and 75.4~89.4%, respectively. The RSDs of these five analytes were less than 6.9%, 8.8%, 9.6%, 9.3% and 9.5%, respectively. T he accuracy and precision of the established method were in line with the analys is requirement and can be applied for the detection and determination of pesticid e residues.(3) After applied in covering soil, the half-life times of Carbendazim, prochloraz, acetamiprid, λ-Cyhalothrin and cyromazine were obtained and were 8.5~12.0 d, 8.5~12.2 d, 33~37 d,13.9~46.2d and 22.4~43.3 d, respectively. The enrichments of Carbendazim, acetamiprid and cyromazine in Agaricus bisporus were observed, with the highest doses up to 0.29, 2.6 and 2.43 mg/kg, respectively. On the contrary, prochloraz and λ-Cyhalothrin haven’t been detected in the soil and compost.(4)Comparing the different degradation rate of acetamiprid in covering soil and substrate, as well as the differences of enrichment of pesticides in Agaricus bisporus, the result showed that the half-life time of acetamiprid in substrate(17~27d) was obviously lower than that in covering soil(33~37d), which meant that acetamiprid degraded more easily in substrate. The highest enrichment level of acetamiprid in Agaricus bisporus was 1.38 mg/kg after applying the pesticides in substrate. Moreover, the enrichment of acetamiprid were observed to decrease significantly in Agaricus bisporus after the pesticides applied in substrate rather than in covering soil. The results proved that the way of applying pesticides had an influence on the enrichment condition of acetamiprid in Agaricus bisporus.