Response of black gram (Vigna mungo L. Hepper) to phosphorus and boron fertilization in acidic soil of Meghalaya

Abstract

A field experiment was conducted to understand the response of black gram (Vigna mungo L. Hepper) to phosphorus and boron fertilization in acidic soil of Meghalaya. For this, four levels of phosphorus (0, 25, 50, 75 kg P2O5 ha-1) and four levels of boron (0, 0.5, 1.0, 1.5 kg B ha-1) were tested in field with sixteen treatment combinations and replicated thrice in split plot design. The native soil had pH 4.99, E.C. 0.42 dS m-1, organic carbon 1.32 percent, available nitrogen 251.35 kg ha-1, available phosphorus 13.68 kg ha-1, available potassium 233.24 kg ha-1 and hot water soluble boron 0.054 ppm. The results revealed that application of phosphorus and boron had synergistic effect on growth and yield of black gram. The plant height of black gram increased with crop development stages i.e. 30 DAS, 60 DAS and at maturity. Increasing phosphorus and boron doses also increased plant height over control at all crop development stages i.e. 30 DAS, 60 DAS and at maturity.The highest plant height at maturity stage under different phosphorus doses was recorded at 75 kg P2O5 ha-1 as 43.43 cm. However, the significant increase in plant height was observed up to 50 kg P2O5 ha-1 with 42.89 cm. Similarly, under different boron doses, the highest plant height (42.60 cm) was observed at 1.5 kg B ha-1 whereas, the lowest plant height was recorded in control plots of P and B as 36.58 and 38.17 cm, respectively at maturity. The seed yield of black gram increased with increasing phosphorus and boron doses. The highest seed yield (10.12 q ha-1) among different phosphorus doses was observed at 75 kg P2O5 ha-1. However significant increase in seed yield was recorded up to 50 kg P2O5 ha-1 with 9.52 q ha-1. Similarly, in case of boron, the significant increased seed yield was observed up to 1.0 kg B ha-1 (9.13 q ha-1) yet the highest seed yield was recorded as 9.43 q ha-1 with 1.5 kg B ha-1. The interaction effect of phosphorus and boron on seed yield was also found significant. The lowest seed yield was observed in control at P0B0 (5.56 q ha-1) and significantly high seed yield was observed at P50B1.5 (10.35 q ha-1) at phosphorus within boron, and in boron within phosphorus, it was recorded 11.03 q ha-1 at P75B1.