亚硒酸钠不同施用方法对水稻硒富集及转化的影响

Effects of Different Sodium Selenite Application Methods on Se Accumulation and Transformation in Rice

【目的】评价亚硒酸钠不同施用方法对水稻硒富集及转化的影响,为利用外源硒生产优质富硒稻谷提供参考依据。【方法】对盆栽优质常规稻基施或在其不同生育期叶面喷施亚硒酸钠,测定亚硒酸钠不同施用方法处理的水稻产量性状及水稻对硒的吸收和累积量,分析水稻对外源硒的综合利用率及稻米的有机硒转换率。【结果】施用亚硒酸钠水稻的产量均低于对照(CK),但差异不显著(P>0.05,下同);仅在分蘖期叶面喷施1次亚硒酸钠的处理对提高水稻各部位硒含量无显著影响,而抽穗前叶面喷施1次亚硝酸钠的处理均能显著提高水稻各部位的硒含量(P<0.05,下同)。施用1次亚硒酸钠处理水稻的糙米和精米硒含量排序为抽穗前叶面喷施>拔节期叶面喷施>基施>分蘖期叶面喷施>CK;施用2次亚硒酸钠水稻的糙米和精米硒含量排序为拔节期+抽穗前叶面喷施>基施+抽穗期叶面喷施>分蘖期+抽穗期叶面喷施>基施+拔节期叶面喷施>分蘖期+拔节期叶面喷施。不同亚硒酸钠施用方法处理水稻的精米有机硒含量占比存在较大差异,但均显著低于CK,其排序为CK(95.0%)>基施(84.0%)>基施+叶面喷施(76.0%~81.0%)>叶面喷施(60.0%~71.0%)。在水稻生长后期(拔节期后)叶面喷施、基施+叶面喷施、全部基施和生长前期(分蘖期)叶面喷施亚硒酸钠,水稻植株的外源硒综合利用率分别为35.80%~79.61%、15.33%~20.58%、2.93%和-4.65%。【结论】亚硒酸钠基施+叶面喷施的外源硒施用方式在保障稻米较高硒含量和有机硒含量占比的同时,能提高水稻对硒的综合利用率,可在富硒水稻生产上推广应用。

【Objective】The effects of different application methods of sodium selenite on selenium enrichment and transformation in rice were evaluated to provide a reference for the production of high quality Se-enrich rice by using exogenous selenium.【Method】A pot experiment was conducted.Indica inbred rice were cultivated,sodium selenite was applied as base fertilizer or leaf fertilizer at different grow stages of rice,and determined the yield characters and Se uptake and accumulation of rice under different exogenous selenium application methods,and then analyzed the exogenous selenium comprehensive utilization rate of rice and organic Se transformation rate in polished rice.【Result】The yield of rice with sodium selenite was lower than control(CK),but there was not significant difference(P>0.05,the same as below).Foliar spraying with sodium selenite only once at tillering stage had no significant effect on increasing selenium content in different parts of rice,while the treatments that contained foliar spraying before heading stage could increase selenium content in all parts of rice obviously(P<0.05,the same as below).The order of Se content in unpolished and polished rice of the treatments that applied sodium selenite only once as followed foliar spraying before heading stage>foliar spraying at jointing stage>base fertilizer>foliar spraying at tillering stage>CK,and the order of Se content in unpolished and polished rice of the treatments that applied sodium selenite twice as followed foliar spraying before heading+jointing stage>base fertilizer+foliar spraying before heading stage>foliar spraying at tillering+heading stage>base fertilizer+foliar spraying at jointing stage>foliar spraying at tillering+jointing stage.Different application methods due to organic Se rate great difference,and all treatments was significant lower than control(CK),its order was CK(95%)>base fertilizer(84%)>base fertilizer+foliar spraying(76%-81%)>foliar spraying(60%-71%).Exogenous selenium comprehensive utilization rate of rice plant by the treatments of late Se foliar spraying application(after jointing stage),base fertilizer+foliar spraying,base fertilizer and only once early Se foliar spraying application were 35.80%-79.61%,15.33%-20.58%,2.93%and-4.65%,respectively.【Conclusion】Therefore,sodium selenite application as base fertilizer+late Se foliar spraying methods can improve Se content and selenium comprehensive utilization rate,and pledge high organic rate simultaneously,and can be used as Se-enriched rice production.