Establishing Fertilization Recommendation Index of Balsam Pear Based on the “3414” Field Experiments in Guangdong

Nutrient abundance and deficiency and fertilization recommendation index of balsam pear were established in Guangdong. Data analysis were based on the “3414”field experiments of trail in Guangdong from 2002 to 2011. Taking plentiful-lack of soil nutrition as an index, soil alkali hydrolyzable nitrogen (N), Olsen-P and available potassium were classified into five classes corresponding to relative yield of 50%,75%,90%and 95%. Fertilizer recommended rates were simulated by the models of one-factor, liner and platform for “3414”field experiments. The results showed that nitrogen fertilizer(N) rates (kg·hm^-2) were 300≤y₁<390, 200≤y₁<300, 140≤y₁<200, 120≤y₁<140, and0< y₁<120 when soil fertilizer was classified as very low, low, medium, high and the highest［w(N)≤70 mg·kg^-1, 70 mg·kg^-1< w(N)≤120 mg·k^-1, 120 mg·kg^-1< w(N)≤165 mg·kg^-1, 165 mg·kg^-1< w(N)≤185 mg·kg^-1 and w(N)>185 mg·kg^-1］, respectively; phosphorus fertilizer (P₂O₅) rates(kg·hm^-2) were 200≤y₂<215, 120≤y₂<200, 80≤y₂<120, 65≤y₂<80 and 0<y₂<65［w(P₂O₅)≤5 mg·kg^-1, 5 mg·kg^-1< w(P₂O₅)≤35 mg·kg^-1, 35 mg·kg^-1< w(P₂O₅)≤95 mg·kg^-1, 95 mg·kg^-1< w(P₂O₅)≤140 mg·kg^-1 and w(P₂O₅)>140 mg·kg^-1］,while potassium fertilizer (K₂O) rates(kg·hm^-2)were 275≤y₃<372, 175≤y₃<275, 110≤y₃<175, 90≤y₃<110 and 0< y₃<90［w(K₂O)<30 mg·kg^-1, 30 mg·kg^-1< w(K₂O)≤85 mg·kg^-1, 85 mg·kg^-1< w(K₂O)≤165 mg·kg^-1, 165 mg·kg^-1<w(K₂O)≤200 mg·kg^-1and w(K₂O)>200 mg·kg^-1］. Compared with the fertilization plentiful-lack index by original system, the soil nutrition content of this research suggested that nitrogen, phosphorus and potassium increased.