Association of Agrometeorologists

Aerodynamic properties of green gram sown in different environments in Indo-Gangetic Plains of West Bengal

S. BASU, PRAMITI K. CHAKRABORTY, R. NATH and P.K. CHAKRABORTY

Field experiments were conducted on green gram during spring-summer seasons of 2011 and 2012 with four dates of sowing and five varieties arranged in a strip-plot design to study the aerodynamic characteristics of green gram at BCKV, Kalyani, West Bengal. Micro-cup anemometers were placed at 0.5, 1.0, 1.5, 2.0 and 2.5 m above the crop canopy on a wooden mast. The zero-plane displacement (d), roughness length (Z0) and drag coefficient (Cd) were found to increase with crop age but the effect of dates of sowing was not prominent except at the final stage of growth. For a LAI value of 1.5, “d” values was 0.254 m and the “Cd” value was 0.015. Both the “Cd” and “d” increased with plant height and LAI. The “d” and “Z0” had significant positive correlation with the total dry matter and crop growth rate irrespective of dates of sowing.

Dates of sowing, drag coefficient, green gram, roughness length, zero-plane displacement