马铃薯施用磷肥技术研究

本文介绍了马铃薯施用磷肥的技术,其研究结果如下: 1.相关性和校验研究表明,Olsen—P是反映土壤供磷力的理想指标。其供磷力低、中、高、极高的临界点(ppm)分别在2、5、12、40。与小麦的肥力指标并不相同。 2.马铃薯磷肥利用率与土壤速效磷含量呈负相关。其回归方程为(?)=24.7-5.691nx,r=-0.567(n=20)。因土施磷是提高磷肥利用率的决定性措施,经过基础研究,提出了一个估产测土确定磷肥用量的便查表。 3.磷作基肥(种肥)优于追肥。其利用率提高10％,产量提高13～17％,每亩纯收益增长17元。 4.施肥部位以全层集中穴施(或条施)效果最优,全面撒施效果最差,利用率相差7％,每亩纯收益相差26.9元。 5.氨磷配合,腐磷混施分别可提高利用率8％、3％。氮磷配合的相互作用因土壤而异。低肥力土壤有每亩93公斤的正连应效果,中肥力土壤无连应,高肥力土壤出现负连应。腐磷混施有每亩40～45公斤的正连应效果。

STUDY ON THE TECHNIQUE OF PHOSPHATE FERTILIZER APPLICATION IN POTATOES

The technique of phosphate fertilizer application was described in this paper and the main results obtained were summarized at follows.1. Olsen-P was an ideal index which reflected the status of phosphorus supply in soil. The low, middle, high and ultra-high critical points of phosphorus supply were 2, 5, 12, and 40 respectively, which were different from the index of fertility in wheats.2. The utilization ratio of phosphate fertilizer in potatoes was negatively correlated to available phosphorus in soil. The regression function wasy=24.7-5.69Lnx and coefficient r=-0.567~(**)(n=20). It was a critical measure that the different amount of phosphate fertilizer was manured according to different soil. A table was set up to determine the amount of manuring phosphate fertilizer by means of the available phosphorus in soil and yield targets in this paper.