滴灌施肥条件下甘薯钾肥分期施用的研究

为确定甘薯生产中钾肥最佳分期施用时期,采用田间试验方法,利用水肥一体化技术,研究了不同分期施钾方式及时期对甘薯产量形成、钾素吸收利用和收获后土壤养分变化的影响。2013-2014年设CK、K1(钾肥基施)、K2(1/2钾肥基施+1/2钾肥追施)和K3(钾肥0基施+钾肥全部后期施用)3种不同施钾方式;在K2和K3这2种施钾方式基础上按移栽后75,100,120 d分期施钾的时期各划分3个处理,试验共8个处理,结果表明,从不同施钾方式和时期来看,与钾肥基施相比,75,100 d分期施钾(1/2基施+1/2追施)能增加甘薯100~160 d干质量、氮钾积累量和钾肥利用效率,2013年产量增加13.8%,13.5%,2014年产量增加19.1%,18.6%。甘薯施钾方式采用1/2基施+1/2封垄期追施的方式,施钾时期在移栽后75 d或100 d甘薯对钾肥的吸收量最高。与钾肥全部基施相比,钾肥1/2基施+75 d 1/2追施和1/2基施+100 d 1/2追施处理钾肥生产效率2013年分别提高11.3%,11.5%,2014年分别提高18.6%,19.0%;2013年钾效率分别提高了6.2,6.3个百分点,2014年提高9.4,9.6个百分点;2013年钾肥表观利用率分别提高8.2,6.2个百分点,2014年分别提高9.1,7.7个百分点。滴灌施肥条件下甘薯施钾方式应采用1/2基施+1/2封垄期追施的方式,且施钾时期在移栽后75~100 d为宜。

The Research of Potassium Application on Sweet Potato in Integration of Water and Fertilizer Conditions

In order to clarify potash best installment application period of sweet potato.To study the effect of yield formation,potassium uptake and the influence of soil nutrient change after harvest on different installments K and period of sweet potato.And eight treatments were carried out:CK(No potassium fertilizer),K1 (Whole potassi-um basal applied),K2(Half potassium fertilizer as basal and half as top dressing at 75,1 00,1 20 d after transplant) and K3(Whole potassium fertilizer top dressed at 75,1 00,1 20 d after transplant)at the year of 201 3 -201 4.The results showed that compared with CK,different ways of K application could significantly improve the biomass,nitro-gen and potassium accumulation in and yield of sweet potato.From the point of different K ways and period,com-pared with the basal application of potash,75 d or 1 00 d stage K (1 /2 +1 /2 Top dressing)could significantly in-crease sweet potato 1 00 -1 60 d biomass,N and K accumulation,N and K use efficiency,201 3 yield increased by 1 3.8%,1 3.5%,201 4 yield increased by 1 9.1 %,1 8.6%.201 3 potassium production efficiency increased by 1 1 .3%,1 1 .5%,201 4 potassium production efficiency increased by 1 8.6%,1 9.0% respectively;201 3 potassium efficiency increased by 6.2,6.3 percentage points,201 4 potassium efficiency increased by 9.4,9.6 percentage points;201 3 potassium apparent use efficiency increased by 8.2,6.2 percentage points,201 4 potassium apparent use efficiency increased by 9.1 ,7.7 percentage points;under the way of conditions of sweet potato,K basal applica-tion should use half potassium fertilizer as basal and half as top dressing,and K application period of 75 -1 00 d af-
ter transplanting is advisable.