Effect of Nutrient Levels on Growth, Yield and Economics of Dolichos Bean (Dolichos lablab L.) in Northern Dry Zone of Karnataka, India

Abstract

The field experiment was conducted at Kittur Rani Channamma College of Horticulture, Arabhavi, during 2016-17 and 2017-18 to investigate the effect of different levels of nitrogen (0 and 25 kg/ha), phosphorus (0, 50 and 75 kg/ha) and potassium (0, 25 and 50 kg/ha) on growth, flowering, yield and economics of dolichos bean. The experiment was laid out in factorial randomized block design comprising of eighteen treatments replicated thrice. Among indivisual NPK levels, the higher level of nitrogen (25 kg N/ha), phosphorus (75 kg P2O5/ha) and potassium (50 kg K2O/ha) recorded significantly maximum growth (plant height, number of primary and secondary branches, leaf area and dry matter content per plant at harvest), early flowering (except N2 level) and pod yield (162.32, 184.14 and 164.75 q/ha) as compared to lower levels in 2016-17 and 2017-18 growing seasons and pooled data. Similarly, amongst all NPK interaction levels, higher fertilizer dose of 25-75-50 kg N-P2O5-K2O/ha recorded significantly maximum growth parameters however, it was at par with 25-75-25 kg N-P2O5-K2O/ha except dry matter content per plant during both the experimental years. Pooled data followed similar trend. On pooled basis, recommended fertilizer dose (25-50-25 kg N-P2O5-K2O/ha) showed early days to 50 percent flowering whereas pod yield (198.44 q/ha) was recorded maximum at higher fertilizer dose (25-75-50 kg N-P2O5-K2O/ha). Similarly, in case of economics, higher fertilizer dose of 25-75-50 kg N-P2O5-K2O/ha recorded highest benefit: cost ratio (5.27) during both the experimental years as well as in pooled data but it was at par with 25-75-25 kg N-P2O5-K2O/ha. Hence, for profitable cultivation of vegetable type dolichos bean in northern transition zone of Karnataka, NPK fertilizer must be applied at the rate of 25-75-25 kg N-P2O5-K2O/ha.