不同生育期叶面阻隔剂对水稻Cd含量的影响  

Effects of Leaf Surface Barrier Agents at Different Growth Stages on Cd Content of Rice

作　　者：刘力[1] 张传华[1] 邓炜 冯丽 何于峰 LIU Li;ZHANG Chuanhua;DENG Wei;FENG Li;HE Yufeng(College of Management,Chongqing University of Technology,Chongqing 400054,China;Chongqing Railway Investment Group Co.,Ltd.,Chongqing 400025,China;Chongqing Fusheng Information Technology Co.,Ltd.,Chongqing 400054,China)

机构地区：[1]重庆理工大学管理学院,重庆400054 [2]重庆铁路投资集团有限公司,重庆400025 [3]重庆阜晟信息技术有限公司,重庆400054

出　　处：《环境科学研究》2023年第12期2382-2392,共11页Research of Environmental Sciences

基　　金：国家社会科学基金重点项目(No.20AJY005);重庆市社科规划一般项目(No.2022NDYB80);2023年重庆市教育委员会人文社会科学研究规划一般项目(No.23SKGH256)。

摘　　要：为研究重庆市主要土壤类型区水稻叶面阻隔剂喷施的最佳时期,提高叶面阻隔技术对水稻籽实的降Cd效率,以合川区(紫色土区)和黔江区(黄壤区)为例,以“恒丰优珍丝苗”为供试品种,选用“楚戈”叶面阻隔剂(富Si型),开展田间对比试验.结果表明:①紫色土区“仅抽穗期喷施叶面阻隔剂”(T2处理组)能将水稻籽实Cd含量(0.151 mg/kg)降至食品安全限值(0.20 mg/kg)以下,“仅分蘖期喷施叶面阻隔剂”(T1处理组)、“分蘖期和抽穗期均喷施叶面阻隔剂”(T3处理组)均会促进水稻籽实对Cd的富集.②黄壤区T1处理组、T2处理组、T3处理组均表现为水稻籽实降Cd效应,但难以保障水稻籽实安全(籽实Cd含量为0.210~0.245 mg/kg),T1处理组水稻籽实降Cd效果优于T2处理组.③土壤铁含量是影响不同生育期喷施叶面阻隔剂水稻籽实降Cd效率的关键,一定厚度的根表铁膜能阻隔Cd向水稻根系内部及地上组织的转运.④喷施叶面阻隔剂能显著提高水稻产量,紫色土区和黄壤区各处理组增产率分别为9.90%~12.25%、5.06%~12.44%.研究显示:建议紫色土区在水稻抽穗期开展叶面阻隔剂喷施;黄壤区在水稻分蘖期和抽穗期两次喷施,但需采取综合调控技术(VIP+n)保障水稻籽实的安全;此外,水稻根和茎叶对Cd具有极强的富集能力,建议水稻收割后将水稻根系离田,提高农田土壤重金属的输出通量.In order to obtain the best growth period for rice leaf surface barrier application in the main soil types in Chongqing and improve the efficiency of leaf surface barrier technology in reducing Cd in rice seeds,‘Hengfeng Youzhen Simiao’seedling was selected as the test variety in Hechuan District(purple soil)and Qianjiang District(yellow soil),and‘Chuge’leaf surface barrier agent(rich Si type)was used for field comparative experiments.The results showed that only at the heading stage(T2)could the Cd content of rice seed(0.151 mg/kg)reduce to below the food safety limit,and only at the tillering stage(T1),tillering stage and heading stage(T3)could the Cd content of rice seed increase.All treatment groups in yellow soil showed the Cd reducing effect on rice seeds,but it was difficult to guarantee the safety of rice seeds(the Cd content of rice seeds was 0.210-0.245 mg/kg).The Cd reducing effect of spraying only at tillering stage(T1)was better than that at heading stage(T2).The soil Fe content is the key to the reduction efficiency of Cd in rice seed applied with leaf surface barrier at different growth stages,and a certain thickness of iron film on the root surface can block the transfer of Cd to the internal and aboveground tissues of rice roots.The yield of rice increased significantly by applying foliar barrier agent.The yield increases of T1-T3 in purple soil area and yellow soil area were 9.90%-12.25%and 5.06%-12.44%,respectively.The research shows that foliar barrier agents should only be applied at heading stage in purple soil area,while at tillering stage and heading stage in yellow soil areas,respectively.However,comprehensive control technology(VIP+n)should be adopted to ensure the safety of rice seeds.In addition,rice roots,stems and leaves have a strong ability to accumulate Cd,so it is recommended to remove rice roots from the field after rice harvest to increase the output flux of heavy metals in farmland soil.

关 键 词：叶面阻隔剂 生育期 水稻Cd 土壤类型 根系离田 

分 类 号：X503.231[环境科学与工程—环境工程] S511[农业科学—作物学]