Biofertilization strategy in low nitrogen supplying soils in Bukidnon and Misamis Oriental [Philippines]

Runa et al. (DA-NOMIARC) evaluated the effects of different commercial biofertilizers on corn yield. The study was conducted in Anlugan, Cabangsalan, Bukidnon and Hinigdaan, El Salvador, Misamis Oriental from 2004 to 2006. Hybrid corn seeds were inoculated with biofertilizers and immediately planted in plots. At planting, all required P, K and half N were applied in band along furrows. The remaining half of N was applied 30 days after planting. The recommended rate (RR) of 120-90-60 NPK/ha was used as inorganic fertilizers. The trials involved: 1 application of RR; 2) 1/2 RR of N + RR of P and K + Bio-N; 3) 1/2 RR of N + RR of P and K; 4) Pure Bio-N; 5) Pure Vital N; 6) RR + Bio-N; 7)RR + Vital N; 8)1/2 RR + Bio-N; 9) 1/2 RR + Vital N; 10) RR + 2t chicken manure; and 11) farmers' practice. Findings revealed the following: During the wet season in Anlugan, the highest average grain yield of 9-10 t/ha was obtained when applied with the RR of inorganic fertilizer + Vital N biofertilizer. This was followed by RR + 2t chicken manure; 1/2 RR N + RR P and K + Bio-N; and RR + Bio-N. Treatments with Bio-N and Vital N gave significantly higher grain yield of more than 8 t/ha compared with the farmers' practice yield of 6.8 t/ha. During the dry season, average grain yield of 9.7 t/ha was highest with 1/2 RR + Bio-N followed by RR + Vital N and RR + Bio-N, with average grain yields of 9 t/ha. Similarly, treatment with Bio-N and Vital N gave average grain yield of more than 8 t/ha compared with the application of inorganic fertilizers alone and farmers' practice with average grain yields of less than 6 t/ha. In Misamis Oriental, a high yield of more than 7 t/ha for one cropping season was attained using biofertilizers. The highest grain yield was obtained from the application of RR + 2t chicken manure, followed by 1/2 RR N + RR P and K + Vital N and the same treatment but with Bio-N. The lowest yield came from the farmers' practice with only 3.53 t/ha. In both locations, net income was higher during the wet season than during the dry season. In Anlugan, the highest net income of P51,710 was obtained from the application of 1/2 RR N + RR P and K + Bio-N, followed by the RR + Vital N with P51,265.50. However, the highest returns of P3.90 for every peso invested came from using pure Vital N. Generally, the application of Bio-N and Vital N in combination with 1/2 RR of inorganic fertilizer under Bukidnon and Misamis Oriental condition gave promising results in terms of yield and economic benefits. This implies that biofertilizers for corn help reduce cost of chemical fertilizers and raise farmers' income