不同含钾物料对冬油菜产量及钾素吸收的效应

采用大田试验研究稻草、稻草灰、硅钙钾肥、枸溶性钾肥和氯化钾肥5种含钾物料对冬油菜产量及钾素吸收的影响。结果显示,在施钾(K_2O)120 kg/hm~2时,各含钾物料的施用均可显著增加冬油菜产量和钾素累积量,与不施钾对照相比,含钾物料处理的油菜增产率为14.5%~34.9%,地上部钾素(K)总累积量增幅为71.8%~143.0%。不同含钾物料的施用效果不同,以枸溶性钾肥效果最好,其次是稻草灰和氯化钾肥。5种含钾物料的钾素表观利用率以枸溶性钾肥、稻草灰和氯化钾处理较高,其显著高于硅钙钾肥和稻草处理。各含钾物料的施用对土壤钾素供应的影响不同,油菜收获后的土壤速效钾含量以氯化钾肥和稻草灰较高,土壤缓效钾含量则以枸溶性钾肥处理最高,均显著高于其他处理。综合结果表明,在等量钾肥投入下,稻草灰和枸溶性钾肥表现出与氯化钾肥相同的施用效果。

Effects of different K bearing materials on the yield and potassium uptake of winter oilseed rape

Field experiments were carried out to study the effects of K-bearing materials ( i. e. straw, straw ash, Si-Ca-K fer-tilizer, citrate acid-soluble potassium fertilizer, and KCl) on the seed yield and potassium accumulation of winter oilseed rape. The results showed that application of K-bearing material fertilizer at the rate of K2 O 120 kg/hm2 significantly increased the yield and potassium accumulation of rapeseed. The seed yield increased by 14. 5% ~34. 9%, while the potassium accumulation of shoot increased by 71. 8% ~143. 0%. However, application effect of different K-bearing materials varied, the treatment of citrate acid-soluble potassium fertilizer was the best, followed by the straw ash and KCl treatment compared with CK treat-ment. Additionally, potassium use efficiency in treatments of the citrate acid-soluble potassium fertilizer, straw ash and KCl treatments was significant higher than those of Si-Ca-K fertilizer and straw. Besides, effects of the type of K-bearing materi-als on soil potassium supply were different, the KCl treatment and straw ash treatment had the higher soil available K and citrate acid-soluble potassium fertilizer had the higher soil slowly available K than the others after the oilseed rape harvest sig-nificantly. The results showed that the straw ash and citrate acid-soluble potassium fertilizer had the same effect of applica-tion with potassium chloride under the same potassium nutrient supply.