早稻品种米镉对不同镉环境的响应

Responds of Rice Cd Accumulation to Different Cd Content Enviromment in Early-rice Cultivar

为探究早稻品种湘早籼32号、湘早籼42号和湘早籼45号对不同镉环境的响应状况,于2014~2016年在湖南省内5个不同镉污染程度和生态条件的试验点进行了多年多点重复试验。研究表明:3个品种在不同年份和地域的不同大气和土壤环境下的镉积累综合变异系数CVY+E:湘早籼32号(61.638%)<湘早籼45号(64.075%)<湘早籼42号(75.125%),即其镉积累年际和地域稳定性:湘早籼32号>湘早籼45号>湘早籼42号;并且各品种各年各点的米镉含量都相对较低,除少数年份或试验点的稻米镉含量超过国家标准0.001~0.157 mg/kg(0.65%~78.67%)之外,其余均低于国家标准,在3 a累计的15个点中的稻米低镉合格率分别为80.0%、80.0%和73.3%,即3个早稻品种表现出了较稳定的较低米镉积累特性。综合多年研究结果,再配套一定的降镉栽培技术,这3个品种在湖南省轻度镉污染地区可以实现达标生产。

In order to research responds of Cd accumulation of early-rice cultivar,Xiangzaoxian32(X32),Xiangzaoxian42(X42)and Xiangzaoxian45(X45)to different Cd content enciromment,the years and sites repeat test had implemented from2014to2016at5test sites with different Cd pollution degree and ecological conditions.The results indicated that the Cd accumulation synthetical variation coefficient(CVY+E)of the3cultivars in different years and sites with different atmospheric and soil environment showed X32(61.638%)<X45(64.075%)<X42(75.125%),meaning their Cd accumulation stability between years and sites were X32>X45>X42.In addition,the content of rice cadmium of the varieties in every test spot each year was relatively low.The cadmium content of rice in the rest spots of three years was lower than the national standard,except for the cadmium content of rice in a few years or test spots,which exceeded the national standard0.001-0.157mg/kg.The low cadmium rice qualified rate of15test spots in three years was respectively80%,80%,73%,which showed that the3early-rice cultivar have a stable Cd low-accumulation characteristic.So,they could be large area promoted and planted with matched low-Cd-cultivation techniques at the mild Cd polluted zone in Hunan Province.