安徽省砂姜黑土地区甘薯钾肥适宜用量研究

Study on Optimum Potassium Application Rate on Sweet-Potato in Shajiang Black Soil in Anhui Province

商薯19淀粉含量高、食味优、产量高,具有适合食用及加工的双重性能,是当前安徽省砂姜黑土地区甘薯主栽品种。甘薯为喜钾作物,根据土壤钾素含量状况,经济合理施钾肥,是甘薯栽培高产高效的基础。通过田间小区试验研究了钾肥用量对甘薯产量、钾素吸收及钾肥利用效率的影响。结果表明,甘薯块根产量、植株钾素累积量随施钾量的增加先增加后降低。在本试验条件下,最高产量施钾量为266.98kg/hm^2,最佳经济施钾量为161.75kg/hm^2。甘薯钾素生理效率、钾素利用效率、钾肥农学利用率、钾肥效率和钾肥利用效率均随钾肥用量的增加而下降。施钾量为K2O 75kg/hm^2时,甘薯钾肥利用效率最高。综合产量水平、经济效益、土壤钾素含量状况,在砂姜黑土区甘薯栽培上K2O用量为75-150kg/hm^2是较为适宜的。

The effects of potassium（K） application rates on storage root yield,K accumulation and use efficiency of sweet-potato were studied in field. The results showed that the storage root yield and K accumulation were increased at first and then gradually decreased with the increment of the K application rate. The K application rate for maximum yield and optimal economical yield was 266. 98 kg /hm^2,161.75kg/hm^2,respectively,under this field experiment conditions. The K physiology efficiency,K utilization efficiency,K agronomy efficiency,K fertilizer efficiency and K fertilizer use efficiency decreased significantly with the increasing of K application rates. Based on sweet-potato storage root yield,K fertilizer use efficiency,economic benefit and available K content,the optimum K2 O application rate was 75- 150 kg /hm^2 in Shajiang black soil area.