Optimization of fertilizer rate based on farmers’ practice in potato-hybrid maize relay cropping system

Abstract

The experiment was conducted at the research field of Agronomy Division, BARI, Joydebpur, Gazipur during consecutive seasons of 2011-12 and 2012-13 to optimize fertilizer rate for potato hybrid maize relay cropping system. Seven treatments viz., T 1 = Farmers" fertilizer dose of potato (FFDP: N 504 P 162 K 309 kg/ha) + Farmers" fertilizer dose of hybrid maize (FFDM: N 0 P 0 K 0 kg/ha), T 2 = FFDP + 100% N of recommended fertilizer dose of hybrid maize (RFDM: N 255 P 55 K 140 S 40 Zn 6 B 2 kg/ha), T 3 = FFDP + 100% N & 25% others of RFDM, T 4 = FFDP + 100% N & 50% others of RFDM, T 5 = Recommended fertilizer dose of potato (RFDP: N 198 P 44 K 194 S 24 Zn 6 B 1.2 kg/ha) +100% N of RFDM, T 6 = RFDP +100% N & 25% others of RFDM, and T 7 = RFDP +100% N & 50% others of RFDM were tested on potato-hybrid maize relay cropping system. Potato (var. Diamant) and hybrid maize (var. BARI Hybrid Maize-9) were used in this experiment. Results indicated that yield of potato (28.38 -28.83 t/ha) did not differ significantly but yield of hybrid maize (4.90 -8.74 t/ha) varied significantly under different treatments. The higher grain yield (8.74 t/ha) of hybrid maize was recorded in farmers" fertilizer dose of potato or recommended fertilizer dose of potato (8.61 t/ha) along with 100% N plus 25% other fertilizers or 100% N plus 50% other fertilizers from recommended dose of hybrid maize. The highest potato equivalent yield (41.94 t/ha) and gross return (Tk. 335520/ha) were obtained from FFDP along with 100% N plus 25% others of RFDM (T 3 ). But the highest gross margin (Tk. 219790/ha) and benefit cost ratio (3.01) were found from RFDP along with 100% N plus 25% others of RFDM (T 6 ). The results revealed that recommended fertilizer rate of potato (N 198 P 44 K 194 S 24 Zn 6 B 1.2 kg/ha) along with 100% N plus 25% other fertilizers from recommended fertilizer rate of hybrid maize (N 255 P 55 K 140 S 40 Zn 6 B 2 kg/ha) might be optimum for potato hybrid maize relay cropping system for obtaining higher economic return.