Ecology, Environment and Conservation Paper

PHENOLOGY, THERMAL REQUIREMENT AND PRODUCTIVITY OF MUNGBEAN AS INFLUENCED BY SOWING TIME

Guriqbal Singh, Navneet Aggarwal, Hari Ram, Harpreet Kaur, K.K. Gill and Poonam Sharma

Abstract

A field experiment was conducted during spring 2008 and 2009 to study the effect of four dates of sowing (10 March, 15 March, 20 March and 25 March) on phenology, thermal requirement, symbiotic efficacy, growth and yield of mungbean. Various agroclimatic indices such as accumulated growing degree days, accumulated heliothermal units and accumulated photothermal units decreased with delay in sowing from 10 March to 15 or 20 March and thereafter increased during 2008, whereas these were increased with successive delay in sowing from 10 March to 25 March during 2009. Reduction in symbiotic parameters such as number of nodules, dry weight of nodules and leghaemoglobin content in nodules was recorded in early sown (10 and 15 March) as compared to late sown (20 and 25 March) crop. During both the years, the yield under 20 March and 25 March sowings was at par, which was, however, significantly higher than the other sowing dates. Yields were low under early sowing dates of 10 and 15 March, possibly due to prevailing low temperatures.