浙江省油菜主产区氮、磷、钾肥效应与土壤测试值关系

对浙江省2006—2008年油菜“3414”试验结果进行了分析,结果表明,油菜预设最佳施肥处理(N₂P₂K₂)产量从1 665 kg/hm²至3 200 kg/hm²间变异,较低产量水平试验土壤pH偏酸、土壤速效钾含量较低。浙江省油菜施肥平均增产率氮(117.5%)>磷(45.1%)>钾(7.3%),单位N,P₂O₅,K₂O平均增产油菜籽以P₂O₅(7.0 kg) >N(4.7 kg)>K₂O(1.7 kg),不同土壤类型氮、磷、钾肥的效应有较大差异。油菜缺素处理相对产量与土壤测试值相关分析结果表明,缺氮区相对产量与土壤有机质、土壤全氮有显著的相关性,土壤有机质和全氮测试值可作为氮肥推荐施肥的指标,而土壤有效磷、速效钾与缺磷区相对产量、缺钾区相对产量相关性较差,只有50%试验点土壤有效磷与缺磷区相对产量有相关关系,70%的试验点土壤速效钾含量与缺钾区相对产量呈显著相关性,表明现有土壤有效磷、土壤速效钾测试方法对指导施肥有一定的局限性,进一步的研究需对不同土壤类型制订相应的指标体系。

Relationship of N, P, K fertilizer efficiency on rapeseed yield and soil test value in main rapeseed production area of Zhejiang Province

The results of experiment“3414”of rapeseed in soil-testing formulated fertilization during the period of 2006 to 2008 in Zhejiang Province were analyzed. The results indicated that the yield of rapeseed ranged from 1 665 kg·hm^-2 to 3 200 kg·hm^-2 in the optimum treatment (N₂P₂K₂), and the yield was lower in soils with lower pH and available K. The average yield\|increasing rates under different fertilization conditions were 117.5% for N fertilizer, 45.1% for P fertilizer and 7.3% for K fertilizer, and the average increasing yield per unit of N, P₂O₅, K₂O were 4.7, 7.0, 1.7 kg, respectively. There was great difference in ferti lizer efficiency among different soil types. The correlation analysis of relative yields in the treatments of nutrient-deficiency and soil testing values showed that the relative yields in the treatments of N-deficiency showed significant correlation with soil organic matter and total N contents, which could be used as the indicator of N fertilization recommendation. On the contrary, poor correlations were found between the relative yields in the treatments of P or K deficiency and soil available P or K, i.e. the significant correlations were only found in 50% investigated sites for P and 70% investigated sites for K, which implied that there were some limitations in soil P or K analysis methods when used for fertilization recommendation. Thus different indicator systems should be made according to different soil types.