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试验结果表明：在速效磷（Ｐ）＞７ｍｇ／ｋｇ的中肥力土壤上种植棉花，霜前皮棉产量与氮磷化肥用量的效应方程为：ｙ＾＝１０５．５５＋２２．４２５Ｎ＋３６．６６Ｐ＋０．３９ＮＰ－０．３Ｎ２－２．２３５Ｐ２，由此模拟出的最佳经济效益施肥量为：尿素６２１ｋｇ／ｈｍ２，重过磷酸钙１６８ｋｇ／ｈｍ２，ＮＰ２Ｏ５为１０．２７，其霜前皮棉经济合理产量为１７７０ｋｇ／ｈｍ２。在较合理的氮磷化肥用量及其配合比例下，化肥当年利用率，尿素可达４０％～６０％，重过磷酸钙为９％～１７％。在适当的磷水平下，棉花产量随施氮量的增加而增加，氮肥是增加单铃数、单铃重进而提高产量的主要因素。但随着施氮量的增加，棉花成熟期推迟，霜前花比例和马克隆值、卜氏强力有下降趋势。
The results showed that the effect equation of cotton yield and nitrogen and phosphorus fertilizer dosage on the medium-fertility soils with available phosphorus (P)> 7mg / kg was y ^ = 105.55 + 22.425N + 36.66P + 0.39NP-0 .3N2-2.235P2, and the optimum economic benefits were calculated as: 621kg / hm2 of urea, 168kg / hm2 of superphosphate, and 10.27% of NP2O5. The economic yield of lint before frost was 1770kg / hm2 . In a more reasonable amount of nitrogen and phosphorus fertilizer and its compounding ratio, the fertilizer utilization of the year, urea up to 40% to 60%, and SSP of 9% to 17%. Under proper phosphorus level, the yield of cotton increased with the increase of nitrogen rate. Nitrogen fertilizer was the main factor to increase single boll number and single boll weight to increase yield. However, with the increase of nitrogen application rate, the maturity of cotton was postponed, the ratio of pre-frost flower and micronaire, Budegurn had a downward trend.