江西红壤旱地花生测土施氮参数研究

以粤油256为供试品种,选取高、中、低肥力的红壤旱地共10块,设计0、135kg/hm2两个施氮水平,研究江西红壤旱地花生测土施氮的参数。结果表明,随着土壤肥力水平的上升,花生产量、生产100kg花生荚果的需氮量、土壤供氮量和土壤氮素贡献率随之提高,而氮肥表观利用率随之下降。高、中、低肥力地块的土壤供氮量分别为222.65kg/hm2、181.53kg/hm2、140.67kg/hm2,土壤氮素贡献率分别为84.88%、79.92%、74.45%,氮肥表观利用率分别为29.37%、33.70%、35.51%;在不施氮条件下生产100kg花生荚果的需氮量分别为6.52kg、6.39kg、6.34kg,而在N135条件下分别为6.60kg、6.44kg、6.37kg。相关分析表明,花生产量、土壤供氮量和花生需氮量与土壤肥力指标中的有机质、全氮、碱解氮、速效钾含量有显著或极显著正相关,而与有效磷含量相关不显著;氮肥利用率与5项土壤肥力指标都呈负相关,但不显著。通过逐步回归,建立了花生产量、土壤供氮量、花生需氮量、氮肥利用率与土壤肥力指标的回归方程,为红壤旱地花生测土施氮提供指导。

Nitrogen application index based on dry red soil for peanut in Jiangxi Province

Nitrogen application to dry red soil for peanut with two N levels （0 and 135kg/hm2） with Yueyou - 256 as the tested variety was carried out in high, middle and low fertility of dry red soil. The results showed that with increased soil nitrogen supply, peanut yield, nitrogen requirement of producing per 100kg pods and the soil ni- trogen contribution rate also increased. The efficency of nitrogen fertilizer decreased with the increased existing ni- trogen supply. The soil nitrogen supply of the tested high, middle and low fertility was 222.65kg/hm2, 181.53 kg/ hm2 and 140.67kg/hm2 respectively. The corresponding soil nitrogen contribution rate was 84.88% , 79.92% and 74.45% respectively and the apparent utilization efficency of nitrogen fertilizer was 29. 37%, 33. 70% and 35.51% respectively. Producing per 100kg pods required 6.52kg, 6.39kg and 6.34kg nitrogen respectively on high, middle and low fertility of upland on NO level, while it required for 6.60kg, 6.44kg and 6.37kg nitrogen re- spectively on N135 level. The correlation analysis suggested that the soil nitrogen supply, peanut yield and nitrogen requirement were significantly positively correlated to the soil organic matter, total nitrogen, available nitrogen and potassium, but not to the soil available phosphorus. Nitrogen use efficiency was negatively correlated to all the five indices of soil fertility, but the correlation was not significant. Finally regression equations of peanut yield, peanut nitrogen requirement, soil nitrogen supply and nitrogen use efficiency with soil fertility index were established, which would provide scientific guidance for peanut＇ s nitrogen application based on soil testing on dry red soil.