N-P-K fertilizer trials on groundnut
1987
Pairoj Phanmongkol | Monton Sewatanon | Santi Teeraporn (Department of Agriculture, Bangkok (Thailand). Div. of soil Science)
Eight combinations of N-P-K fertilizers with inoculation were compared in farmers' fields in three provinces in the rainy seasons of 1982-1985 to determine the economic rate of fertilizer under various soil fertility levels. Results in Pitsanulok province, average over 15 sites (1983-85), showed that application of 3 kg/rai gave the highest VCR (12.8) with a yield increase of 62 kg/rai. Application of 6 kg N/rai gave the highest yield increase and the highest profit, but the VCR reduced to 7.6. For phosphate fertilizer, highest VCR was obtained when applied at the rate of 9 kg P2O5/rai. The high rate (18 kg P2O5/rai) gave lower VCR (2.5), though yield increase and profit were highest. For potassium fertilizer, highest yield increase and highest profit were obtained from the application at a rate of 12 kg K2O/rai. At this rate, the VCR was 4.0. Averaged over 20 sites in Chachoengsao province (1982-1985) nitrogen fertilizer at a rate of 3 kg N/rai gave the highest VCR (12.3) and the highest profit (441 bath/rai). Application of 9 kg P2O5 showed the highest VCR (3.5) and the highest profit (398 Bath/rai), while application of 6 kg K2O/rai gave the highest yield and profit with a VCR of 7.4. Results of the tests in Nakhon Ratchasima (20 sites, 1982-1985) showed no response of groundnut to nitrogen fertilizer and low response to phosphate fertilizer. Thus, application of nitrogen and phosphate fertilizer in this province would be uneconomical. Only a moderate response to K fertilizer was observed, and application of 6 kg K2O/rai gave the highest profit (122 Bath/rai) and the highest VCR (3.6) with a yield increase of 22 kg/rai.
显示更多 [+] 显示较少 [-]