施氮量对马铃薯磷钾利用和土壤磷钾含量的影响

为了提高肥料利用效率,采用田间试验方法,在基施等量磷肥(P2O5150 kg/hm2)和钾肥(K2O 360 kg/hm2)条件下,研究施氮量(0、80、160、240 kg/hm2)对马铃薯(Solanum tuberosum L.)费乌瑞它磷钾利用和土壤磷钾含量变化的影响。结果表明,马铃薯干物质、全磷及全钾积累总量随施氮量的增加而递增,但施氮量达160 kg/hm2以上时再增施氮肥增加不显著;增加施氮量,磷肥和钾肥的肥料效率略呈上升趋势,但磷肥和钾肥的收获指数、经济效率及生理效率略呈下降趋势。马铃薯收获后,种植地土壤尤其是0~30 cm土层的速效磷和速效钾含量显著增加,但各土层速效磷和速效钾含量随施氮量的增加呈递减趋势。施氮量还影响干物质、全磷及全钾在马铃薯各器官的分配。因此,本研究条件下,N、P2O5、K2O施用量可在160、150、360 kg/hm2基础上适当减量。

Effects of Nitrogen Application Rates on Winter Potato Phosphorus,Potassium Utilization and Soil Phosphorus,Potassium Content

In order to improve fertilizer utilization-efficiency,a field experiment was conducted with equal amount of phospho-rus fertilizer (P2O5 150 kg/hm2) and potassium fertilizer (K2O 360 kg/hm2) application, and the effects of N application rates (0,80,160,240 kg/hm2) on the phosphorus,potassium use efficiency of potato cultivar Favorite and the change of soil phos-phorus, potassium content of soil were investigated. The results showed that the total dry matter,total P and total K accumu-lation amount of potato were increased significantly with the N applied, but there were no significant difference between ap-plication 160 kg/hm2 and application 240 kg/hm2. The fertilizer efficiency of phosphorus and potassium was increased with the increase of N application rates, but the harvest index, economical efficiency rate,physiology use efficiency of phosphorus fer-tilizer and potassium fertilizer were decreased slightly. After potato harvest, the content of available phosphorus and available potassium in 0~30 cm soil layer increased significantly, but the content of available phosphorus and available potassium in soil profile were decreased with the increase of N application rates. The N application rates had influence on dry matter, to-tal P and total K distribution in potato organs. Therefore,the N,P2O5,K2O application amount could be reduced appropriately on the basis of 160 kg/hm2,150 kg/hm2,360 kg/hm2 in the present study.