施钾条件下杂交水稻氮磷养分吸收利用特点

对浙江省金华市郊区石门农场灌溉稻区进行连续4年定位钾肥试验,结果表明,钾素促进氮磷养分向水稻穗部的输入,故在增产的基础上,同不施钾处理比较,施钾后杂交稻氮的总吸收量增加7.1～9.3kg/hm2,利用效率提高3.7～7.1%;磷的总吸收量增加1.0～2.0kg/hm2,利用效率提高2.0～7.7%。同常规稻比较,每季杂交稻氮和磷的平均总吸收量分别高出7.6kg/hm2和1.2kg/hm2;氮和磷的利用效率平均高出3.1kg/kg和34.7kg/kg;在养分的吸收、积累以及利用效率方面表现出明显的生理优势1]。因此,在杂交水稻的生产实践中,应相对增加钾肥的施入量,从而提高氮肥和磷肥的利用效率。

Natune of Nitrogen and Phosphorus uptake by a Hybrid Rice under the Potassium Fertilizer Treatment

A four year′s site-specic potassium experiment was conducted in a irrigated rice field near the suburb of Tinhua city of Zhejiang province. The results indicated that Potassium could promote nitrogen and phosphorus importing from stem to panicle of rice. Based on yield,the total N uptake by the hybrid rice was increased to 7.1 9.3 kg·ha-1, and the nutrient use efficiency was enhanced by 3.7 7.1%,while the P uptake was increased to 10 2.0 kg·ha-1, and was nutrient use efficiency was enhanced by 2.0 7.7%. Average total N and P uptakes by the hybrid rice were 7.6 kg·ha-1 and 1.2 kg·ha-1 higher, and N and P use efficiency were 3.1 kg·kg-1 and 34.7 kg·kg-1 higher than an inbred rice, respectively. Compared with the Inbred rice,the Hybrid rice behaved physiologically advantage in nutrient uptake and use efficiency. In hybrid rice cropping practice, therefore,K application should be increased comparatively.