Screening Of Low Lead And Cadmium Enrichment Vegetables And Construction Of High Efficient Rotation Model In Dongguan Area

Vegetables takes an extremely important place in agricultural production in Dongguan.According to the Dongguan Statistical Yearbook data show: In 2009,the city's vegetable sown area was 306 thousand acres,accounting for more than 80% of the total crop area,and vegetables total output was 400 thousand tons,that was the highest yield of all crops.At the same time,Dongguan is an important vegetable base for Hongkong.However,the rapid development of reform and opening upto 20 years,industrialization of Dongguan City,caused industrial "three wastes",resulting in highly detection rates of heavy metals in vegetables,lead(Pb)was one of the most serious pollution in vegetables.The heavy metal pollution of vegetables,not only affects the vegetable exports and farmers income,and also impacts on human health.The screening of edible part of the low concentration of Pb and cadmium(Cd)in varieties of vegetables,constructing vegetable rotation pattern research,building efficient cropping pattern,could provide effective guidance to heavy metal contamination of Pb and Cd in vegetable planting of Dongguan city,moreover could reduce the Pb and Cd accumulation in vegetable,improve comprehensively the quality of vegetables and achieve pollution-free production.The main results of this study are as follows: 1.Rhizome vegetables screening of low enrichment Pb and CdAfter screening,Baishananpan radish,Selection Meihuawang radish,Short leaf Huochetou radish are Cd low cumulative root vegetables,Short leaf 13 Huochetou radish,Beijing Xinlimei radish,Sijimanshenhong radish are Pb low cumulative root vegetables;both Cd and Pb low accumulation of root vegetables is short leaf 13 Huochetou radish.Spring and autumn 2 white lettuce is Cd low cumulative stem vegetables,super hongxiangjianye asparagus lettuceis Pb low cumulative stem vegetables.2.Leafy vegetables screening of low enrichment Pb and CdBoth Cd and Pb low accumulation leafy vegetable: Heiyekuishanzhongjiaotian pakchoi,Sijiaijiaoheiyetian pakchoi,Tianzhu mustard.3.Melons and fruit vegetables screening of low enrichment Pb and CdAmong four varieties Yuexiu No.3 cucumber,Fengyouyouqing bean,Kangxiawan green pepper,Yifeng No.4 tomato,Fengyouyouqing bean and Yuexiu No.3 cucumber absorbed less Pb and Cd,and has a planting higher safety factor in light and medium polluted soil of Pb and Cd.4.Construction of efficient rotation modelAmong the 3 planting models,“model 3 Short leaf 13 Huochetou radish – Yuexiu No.3 cucumbr--Fengyouyouqing bean” showed the contens of Cd in edible parts of vegetables kept at a low level in all of seasons.This rotation plant model was recommended as planting pattern in polluted field.