福建菜后稻氮磷钾施肥指标研究

NPK Fertilization for Rice on Fields in Fujian after Vegetable Harvest

为建立福建菜后稻氮磷钾施肥指标,在福建省蔬菜主产区进行63个菜后稻氮磷钾肥效田间试验。结果表明,菜后稻的空白区产量与平衡施肥产量之间满足线性关系,菜田对稻谷产量的平均贡献率为79.1%,施用氮磷钾平均增产16.5%、6.7%和9.0%。"极高"土壤肥力等级的碱解氮、Olsen-P和速效钾含量分别为>230mg.kg-1、>54 mg.kg-1和>140 mg.kg-1,"中低"土壤肥力等级则分别为<200 mg.kg-1、<19mg.kg-1和<74mg.kg-1,"高"土壤肥力等级的相应指标范围则介于二者之间。"极高"土壤肥力等级的超高产水稻经济施肥量为N 150kg.hm-2、P2O545kg.hm-2和K2O 92kg.hm-2,"高"土壤肥力等级的普通水稻品种经济施肥量为N 62kg.hm-2、P2O520kg.hm-2和K2O 57kg.hm-2,"中低"土壤肥力等级则为N120kg.hm-2、P2O537kg.hm-2和K2O 40kg.hm-2。土测值与菜后稻的推荐施肥量之间满足指数模型,建立了不同土壤肥力等级的土测值与推荐施肥量的回归方程式,达到了因土施肥的目的。

Sixty-three field experiments to determine the rice′s responses to NPK fertilizations after vegetable harvest were conducted to establish the optimal fertilization indices for the province.The rice yield under the blank and balanced fertilization showed a linear function mathematically.The average contribution rate of soil nutrients to the rice yield was 79.1%,and the average yield increases attributed to the N,P and K applications were 16.5%,6.7% and 9.0%,respectively.The critical indices of alkali-hydrolyzable N,Olsen-P and available K in the soils of ＂extremely high fertility＂ were greater than 230 mg·kg-1,54 mg·kg-1 and 140 mg·kg-1,respectively;less than 200 mg·kg-1,19 mg·kg-1 and 74 mg·kg-1,respectively,in the soil of ＂low-to-medium fertility＂;and,in between in the soil of ＂high fertility＂.In general,the economic application rates for the soils of extremely high fertility were N 150 kg·hm-2,P2O5 45 kg·hm-2,and K2O 92 kg·hm-2;N 62 kg·hm-2,P2O5 20 kg·hm-2 and K2O 57 kg·hm-2 for the soils of high fertility;and N 120 kg·hm-2,P2O5 37 kg·hm-2 and K2O 40 kg·hm-2 for the soils of low-to-middle fertility.The correlation between the soil analytical results and the recommended fertilizations fitted an exponential model,which would provide a guideline for appropriate fertilization.