Fertilization Research Of Different Phosphate Dosages And Potassium Ratios On Winter Potato

In order to provide a reference for rational application of fertilizer in potato cultivation in Huidong County, we chose Pinghai town as the research place. We studied the variation of potato dry matter accumulation, NPK nutritional characteristics, yield, quality and economic benefits under different phosphate fertilizer dosage and application of potassium fertilizer. We set 4 phosphate(P2O5) dosages, that was 0, 45.0, 90.0, 135.0 kg?hm-2, respectively, marked as P0, P1, P2, P3; In addition, potassium sulfate and potassium chloride ratio test had been set: total potassium(K2O) amount was 312.0 kg?hm-2, 3 potassium source ratios were K2SO4: KCl =1:0, 0:1, 1:1, respectively, marked as K2SO4, KCl and combined application treatments. The main findings were as follows:(1) With the increase of phosphate fertilizer application amount, total output of tuber, commodity yield, total output value and economic benefits all sorted as P1>P2>P3>P0, such as P1 with 57576.0 kg?hm-2, 55848.7 kg?hm-2, 134900.6 yuan?hm-2 and 109242.4 yuan?hm-2, compared with P0 treatment, P1 treatment increased by 16.2 %, 16.6 %, 16.5 % and 20.9 % respectively. In addition, P1 treatment had better potato tubers quality, starch production, crude protein content and vitamin C level.(2) With the advance of the growth and development period, potato dry matter accumulation was on rising trend. Accumulation rate performed "slow-fast-slow" change, the maximum accumulation rate appeared in 31~45 d after good seedling emergence(except P3 treatment). With the growth period, rate of leaf and stem dry matter distribution decreased gradually, however,tuber dry matter allocation rate was rising. Tuber dry matter allocation rate was more than 88.3% in73 d after good seedling emergence.(3) With the advance of the growth and development period, NPK concentration in whole potato plant declined; N concentration decreased at the fastest time in 17~31 d after good seedling emergence, while P and K were in 3~17 days; Excess phosphate fertilizer can reduce the NPK concentration in late stage of potato plants growth. With the advance of the growth and development period, P accumulation in whole plant increased persistently. P2 processing had been the highest harvest tuber PK accumulation; P3 processing had been the highest harvest tuber N accumulation.(4) Total output of tuber, commodity yield, total output value and economic benefits of potassium ratios fertilization research all sorted as combined application> K2SO4> KCl, compared with K2SO4 treatment, combined application treatment increased by 9.8 %, 6.8 %, 9.2 % and 10.5 %, respectively, KCl treatment reduced by 2.1 % and 1.2 % in output value and economic benefits. Compared with the K2SO4 and KCl, combined application increased by 12.0 % and 18.2 % in starch production, respectively.(5) The maximum accumulation rate of K2SO4 and combined application treatments appeared in 31~45 d after good seedling emergence, but KCl treatment delayed 14 d. The maximum dry matter accumulation rate in order was: combined application> K2SO4> KCl.