Phosphorus, nitrogen, sulfur, boron and zinc fertilization effects on soybean yield and quality

Abstract

Seed protein concentration in argentine soybean has been steadily decreasing in the last decade and is causing severe losses to the soy milling industry. Thirty-one field trials were conducted in the Pampean region of Argentina during four seasons to evaluate the effect of different fertilization strategies-1: Control without fertilization, 2: P (22 kg ha -1 ); 3: P+S (22 kg ha -1 P and 13 kg ha -1 S); 4: PP+SS (40 kg ha -1 P and 24 kg ha -1 S); 5: P+S + Zn (T3 + 1,25 kg ha -1 Zn); 6: P+S + foliar B ( T3 + 0,1 kg ha -1 B) and 7: P+S + foliar N (T3 + 10 kg ha -1 N) on soybean yield, seed protein concentration (PC), seed oil concentration (OC) and profat index (PF). In most site-years (58,1%), positive yield and protein responses were observed with PP+SS vs Control treatment, resulting in the largest response magnitudes compared to the rest of the treatments. Treatments with foliar N, preplant broadcast Zn and foliar B applications over T3 had no consistent effects on the studied variables. This study shows that proper fertilization strategies can increase soybean yield and seed quality.