氮磷钾肥对马铃薯营养状况及块茎产量的影响

试验分别在甘肃省景泰县、内蒙古自治区达拉特旗和河北省沽源县3个马铃薯生产基地进行,在基地常规N、P2O5、K2O肥施用量分别为300、345、375kg/hm2的基础上,研究改变磷、钾、氮肥用量对马铃薯营养状况、块茎产量以及土壤养分的影响。试验结果表明,氮、磷、钾肥用量分别从N300、P2O5345、K2O375kg/hm2降低到180、180、225kg/hm2,对植株干物质累积量没有显著影响,3个基地都呈相同的趋势;3个基地不同处理的块茎产量也没有显著性差异。因此,在试验条件下,氮、磷、钾肥用量和比例为180-180-225的施肥处理,其经济效益较高。施肥对土壤养分含量有较大的影响,特别是磷肥,当施用磷肥后,土壤速效磷含量显著提高,而且主要存在于表层土壤(0￣20cm),这说明缺磷土壤通过施用磷肥,可提高土壤有效磷水平。

Effect of Different N, P2O5, K2O Fertilization rate and Ratio on Nutrient Status and Tuber yield of Potato

The field experiments were conducted to study on the effect of different N, P2O5, K2O fertilization rate and ratio on nutrient status and tuber yield of potato in three potato production bases. According to traditional application rate, N-P2O5-K2O =300-345-375 (kg/hm2), the fertilization rate of N, P2O5, K2O was decreased to 180, 180, 225 kg/hm2, respectively. The results indicated that the decrease of fertilization rate of N, P, K from 300 to 180, 345 to 180, 375 to 225 kg/hm2 respectively, did not lead to significantly reduce shoot biomass and tuber yield. Hence, after comparing the economic benefit among different treatments, the fertilization rate and ratio N-P2O5-K2O =180-180-225 was the more economical than others. Additional, the effect of fertilization on the nutrient content in soil was discussed too. The phosphorous fertilizer application increased the Olsen-P of soil markedly, especially for the 0~20cm profile soil.