Research on Fertilizer Absorption Rule of Dry Land Sorghum

In order to increase the yield of dry land sorghum,the fertilizer absorption rule was studied by determining the nutrient content in sorghum plants at different growth stages in laboratory.The results indicated that the absorption speed of sorghum to nitrogen,phosphorus and potassium was slower and the amount was less at the earlier growth stage;the speed was up to peak and the amount was the most at the middle growth stage,in which,the absorption peaks of N and K were from jointing stage to heading stage,while that of P was from heading stage to filling stage;the speed decreased and the amount reduced at the later growth stage.The absorption amount of K was the most,which followed by were N and P.The absorption ratio of N,P and K was 1 ∶ 2.61∶ 0.29 in the grain formation stage.