钾肥用量对瘠薄地甘薯产量和钾肥利用率的影响

为探索瘠薄地条件下甘薯的最佳钾肥用量,以淀粉型甘薯品种济薯25为试验材料,设3个处理:CK(不施钾肥)、K1(K₂O,150 kg·hm^-2)、K2(K₂O,300 kg·hm^-2),研究钾肥用量对瘠薄地甘薯产量和钾肥利用率的影响。结果表明,施钾显著提高了鲜薯和薯干产量,K1增产幅度较大,鲜薯和薯干产量分别较CK增加22.84%和32.13%,K2分别较CK增产11.39%和20.30%。施钾促进了甘薯块根的膨大,K1和K2的块根膨大速率均显著高于CK,T/R值均显著低于CK。施钾促进干物质的积累,K1和K2的叶片、叶柄、茎和纤维根干重以及总生物量显著高于CK,且K1优于K2。施钾显著增加了甘薯各器官的钾素积累量,且整体表现为施钾量越多,各器官的钾素积累量越高。钾肥利用率随施钾量的增加而降低,K1的钾素产块根效率、产干物质效率、钾肥吸收利用率、钾肥农学利用率和钾肥偏生产力均显著高于K2。在本试验瘠薄地条件下,钾肥的最佳用量为150 kg·hm^-2。本研究为瘠薄地甘薯田间施肥提供...

Effects of Amount of Potassium Fertilizer on Yield and Potassium Utilization Efficiency of Sweetpotato in Barren Land

In order to determine the optimum amount of potassium fertilizer of sweetpotato in barren land. The high-starch cultivar Jishu25 was studied to explore effects of amount of potassium fertilizer on yield and potassium utilization efficiency by sweetpotato. Three treatments were designed: CK (no potassium fertilizer)、K1 (K₂O: 150 kg·hm^-2)、K2 (K₂O: 300 kg·hm^-2). The results showed that, potassium application significantly improved fresh yield and dry yield. K1 treatment had the highest increase, while the fresh yield and dry yield of which increased by 22.84% and 32.13%, respectively, followed by K2 treatment, increased by 11.39% and 20.30% respectively. Potassium promoted root tuber thickening. The thickening rate of root tuber of K1 and K2 treatments were higher than CK, while the T/R value were lower. In addition, potassium promotes dry matter accumulation of sweetpotato. The dry weight of leaf, petiole, stem, fibrous root, and total biomass of K1 and K2 treatments were higher than CK. K1 treatment was better than K2 treatment. Potassium application significantly increased potassium accumulation in organs. The more potassium application rate, the higher potassium accumulation. The utilization efficiency of potassium decreased with the increase of potassium application rate. Tuber root production efficiency, dry matter production efficiency, absorption and utilization efficiency, agronomic efficiency, and partial productivity of potassium of K1 treatment were higher than those of K2 treatment. The optimum amount of potassium fertilizer of sweetpotato in barren land was 150 kg·hm^-2. The study provides a theoretical basis for fertilization in barren land of sweetpotato, and achieved the purpose of cost saving and efficiency increasing.