摘要
采用盆栽试验,研究了不同供氮水平对花生植株硝酸盐累积、分布及产量的影响。结果表明,花生荚果产量随施氮量的增加呈二次曲线变化趋势,当施用量为N 150.9 kg/hm2时产量最高;植株硝酸盐含量、累积量和累积速率基本随施氮量的增加而提高。同一氮素水平,不同器官的硝酸盐含量因生育期不同存在较大差异,幼苗和花针期茎中的含量最高,饱果成熟期地下器官的含量明显高于地上器官;全生育期叶片和茎中的硝酸盐含量随生育进程逐步降低,而子仁和果壳中含量逐步增加;收获时硝酸盐在茎中的分配比例随施氮量的增加而提高,在根中的分配比例下降。在一定的氮素水平内(≤N135 kg/hm2),硝酸盐在子仁中的分配比例与供氮水平一致,但过量施氮会导致在营养体中的比例上升,子仁中的比例下降,其它器官规律不明显。在本试验范围内,子仁及其它器官中的硝酸盐含量均未超出WHO和FAO制定的标准,未造成硝酸盐污染;但过量施氮能够显著提高花生荚果和耕层土壤硝酸盐含量。因此,综合考虑花生品质、单位肥料的增产量以及生态效应,花生适宜的施氮量为N 90 kg/hm2。
Pot experiment was conducted to understand the influence of N rates on accumulation and distribution of nitrate and yield in peanut. Results showed that the pod yield increased quadratically with N rate and the maximum yield could be reached at the N rate of 150.9 kg/ha. The relative content, accumulated amount and accumulating rate of nitrate in peanut plant increased with N rate. The nitrate content in various organs, at the same N level, differed with growth stages. The content was high in stem at seedling stage and pegging stage and in underground-organs at pod-filling stage. Nitrate content decreased in leaves and stems and increased in pod with plant growth and development. At maturing stage, increasing N rate could result in an increase of the distribution percentage of nitrate in stem and kernel （N≤ 135 kg/ha） while a decrease in root and no obvious trend in other organs. The excessive application of N （for example, N180 kg/ha） may increase the distribution percentage in vegetable part and reduce that in kernel. The nitrate content of kernels and all other organs for all treatments was less than the nitrate-content standard set up by WHO and FAO, indicating no nitrate pollution in peanut products. But excessive N was able to greatly enhance the nitrate concentration in both peanut products and tillage layer of soil. The suggested N rate was 90 kg/ha that would optimize yield, quality of product and ecological effect.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2007年第5期915-919,共5页
Journal of Plant Nutrition and Fertilizers
基金
"十五"国家科技攻关计划"花生优质高效生产技术研究与示范"(2001BA507A-07)资助
