广东省荔枝园土壤农药残留现状研究

荔枝收获完毕后在广东省荔枝主产区采集208个荔枝园土壤样本,检测了9种荔枝常用农药甲霜灵、代森锰锌、多菌灵、溴氰菊酯、氯氰菊酯、三氟氯氰菊酯、敌百虫、乐果和敌敌畏的残留含量.结果表明,农药检出率为氯氰菊酯(59.1%)多菌灵(51.0%)代森锰锌(11.1%)甲霜灵(6.7%)三氟氯氰菊酯(3.4%).乐果和敌敌畏仅在个别果园检出,溴氰菊酯和敌百虫均未检出.土壤同时检出不同种类农药果园的百分数为只检出1种农药(40.4%)同时检出2种(31.3%)未检出(18.8%)同时检出3种(8.2%)同时检出4种(1.4%).检出的7种农药中,代森锰锌残留平均含量最高达39.05μg·kg-1,氯氰菊酯次之为7.83μg·kg-1.其它5种农药平均含量为0.19～1.65μg·kg-1.整体上广东省荔枝园土壤农药残留状况较轻.

Pesticide Residual Status in Litchi Orchard Soils in Guangdong, China

Litchi is a famous tropical and subtropical fruit originated in South China. Guangdong is one of the most important litchi production areas in China. Two hundred and eight soil samples were collected in litchi orchards after harvesting the fruit, in which nine often-used pesticides including metalaxyl, mancozeb, carbendazim, deltamethrin, cypermethrin, cyhalothrin, dipterex, dimethoate and dichlorvos were detected. The results showed that the detectable rates of various pesticides were ranked cypermethrin (59.1%) > carbendazim (51.0%) > mancozeb (11.1%) > metalaxyl (6.7%) > cyhalothrin (3.4%). Dimethoate and dichlorvos were detectable in few soil samples, and deltamethrin and dipterex were undetectable in all samples. The percentages of soil samples where different pesticides could be detected in one sample followed the order: one pesticide detectable (40.4%) > two pesticides simultaneously detectable (31.3%) > pesticide undetectable (18.8%) > three pesticides simultaneously detectable (8.2%) > four pesticides simultaneously detectable (1.4%). The concentrations of mancozeb in detectable samples averaged 39.05 microg x kg(-1), and that of cypermethrin was 7.83 microg x kg(-1). The mean concentrations of the other five pesticides ranged from 0.19 microg x kg(-1) to 1.65 microg x kg(-1). Totally, the pesticide residue status in litchi orchards in Guangdong was venial.