Abstract: To explore the effect of potassium(K) and nitrogen (N) on yield and quality of tuber of sweet potato YS25 in soil with high fertility,used two factors of three levels completely randomized block design of experiment,with 3 N treatments(0,45,90 kg/ha) and 3 K₂O treatments (0,75,150 kg/ha),included 9 combinations of K and N treatments,were designed.The results showed that:High fertility soil nitrogen fertilizer could be added sweet potato vine length,shoot fresh weight,T/R value(Ratio of fresh weight of stem and leaf to fresh weight of underground),and improve the tuber of sweet potato protein, glucose and sucrose content and high fertility soil nitrogen fertilizer situation and root dry mass of fresh,the content of starch and fructose decreased.K fertilizer could significantly increase the root fresh and dry weight,potato rate and starch and glucose content;promote the sweet potato of Mg absorption,decreased the uptake of Ca by sweet potato.In nitrogen and potassium interaction conditions,sweet potato branching number,tuber number and Vc,protein,sucrose,glucose,fructose content with no fertilizer treatment were improved compared; fresh tuber yield and N fertilizer and potash fertilizer application interaction,namely when no N and K₂O 150 kg/ha,sweet potato yield reached the highest,with no fertilization treatment increased 10 825.5 kg/ha,an increased of 29.2%.At the same time in the implementation of N 90 kg/ha,without K₂O,the sweet potato yield was lowest,compared with no fertilization treatment was 1 435.5 kg/ha,a declined of 3.9%.Therefore,in the high fertility soil,the high yield and good quality of fresh edible sweet potato should be obtained by the application of no or less nitrogen fertilizer and the appropriate amount of potassium fertilizer.

Key words: Fresh-eating sweet potato, High fertility soil, Potassium application combined with nitrogen, Yield, Quality

CLC Number: 

• S143

• S531