【摘要】 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);其中分蘖期喷施的降Cd效果最佳,Cd含量比对照下降了19.6%~35.1%。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。更多还原

【Abstract】 The pot experiment was carried out in this study to further explore the impact of plant nutrient, slaked lime, pokeberry root powder on cadmium(Cd) absorption by rice, and to screen practical agronomic measures which could reduce the accumulation of cadmium. In the control treatment nothing but water was sprayed into rice, while in other treatments, plant nutrient, slaked lime and pokeberry root powder were sprayed on rice at the tillering stage, the heading stage and the dough stage, respectively. The plant samples and soil samples were collected after the harvest and then analyzed on aimed indexes. The results showed that Cd contents in rice plants were significantly decreased, total Cd contents in brown rice were significantly(P<0.05) decreased after rice was sprayed with plant nutrient, slaked lime and pokeberry root powder at different growing stages. However, while rice was sprayed with the three materials all at the tillering stage, the heading stage and the dough stage, the total Cd contents in brown rice were decreased by a maximum reduction that was 53.4% to 57.5% below that of the control, which was significantly(P<0.05) lower than other treatments. Meanwhile, the biggest reduction of Cd in rice sprayed with the three materials at the tillering stage was 19.6% to 35.1% below that of the control, which was significantly(P<0.05) lower than other treatments. In conclusion, spraying plant nutrient, slaked lime and pokeberry root powder on rice at different growing stages could not only reduce the absorption accumulation of Cd by root system, but also change the activities of rice and physical and chemical properties of soil, and then inhibit the absorption of Cd by the root system and the transfer of Cd in the rice plant. Therefore, the multiple factors may be the main causes of reducing Cd contents in the brown rice when the three materials are sprayed on rice at different growing stages.更多还原