叶面喷施植物营养剂、熟石灰、商陆根粉对水稻的降镉效果

Effects of Cadmium Reduction on Rice by Spraying Plant Nutrient, Quicklime and Pokeberry Root Powder

为探索叶面喷施植物营养剂、熟石灰、商陆根粉对水稻Cd吸收积累的影响,筛选出降镉的实用农艺措施,采用盆栽试验,在水稻分蘖期、抽穗期、蜡熟期进行植物营养剂、熟石灰、商陆根粉喷施处理,成熟后采集水稻植株和土壤样品进行相关指标测定。结果表明:在水稻不同生育期喷施植物营养剂、熟石灰、商陆根粉可显著降低水稻植株Cd含量,尤其是糙米Cd含量(P<0.05),同时显著降低植株根系对Cd的吸收系数(P<0.05)和次级转运系数;在水稻分蘖期、抽穗期、蜡熟期3次喷施上述药剂对糙米Cd含量的降低程度最大,其含量比对照下降53.4%~57.5%,且与其他处理差异显著(P<0.05)。综上认为,在水稻不同生育期喷施植物营养剂、熟石灰、商陆根粉不仅可以减少根系对Cd的吸收积累,还可能改变水稻的新陈代谢、生理活动及土壤理化性质,进而抑制根系吸收Cd以及Cd在植株内的转移。

The pot experiment was carried out to further explore the impact of plant nutrient,quicklime,pokeberry root powder oncadmium absorption by rice,and to screen practical agronomicm easures which could reduce the accumulation of cadmium,In the controltreatment nothing was spraied into rice,While in other treatments,plant nutrient,quicklime and pokeberry root powder were spraiedinto rice as the tillering stage,the earing period and the wax period,respectively.The plant samples and soil samples were collectedafter the harvest and then were subjected to analyze aimed indexes.The results showed that Cd contents in rice plants were significantlydecreased,but total Cd contents in brown rice were significantly(P<0.05)decreased after rice was spraied with plant nutrient,quicklimeand pokeberry root powder at different growing stages.However,while rice was spraied all at the tillering stage,the earing period andthe wax period,the total Cd contents in brown rice was decreased with a maximum reduction that was53.4%-57.5%below the control,which was significantly(P<0.05)lower than other treatments.Meanwhile,the biggest drop reduction of Cd was spraied in tillering stage,19.6%-35.1%below the control,which was significantly(P<0.05)lower than other treatments.activities of rice and physical and chemicalproperties of soil,then and inhibit the absorption of Cd by the root system and transfer of Cd in the rice plant.Therefore,the multiplefactors may be the main causes of reducing Cd contents in the brown rice when they are spraied at different growing stages.