Effect of Growing Degree Days on Yield Attributes and Yield of Groundnut

The objective of this study was undertaken to find out the optimum sowing window and the amount of heat units required to change their phonological development for groundnut. An field experiment was conducted at experimental farm of Agricultural College and Research Institute, Eachangkottai during Margazhi pattam 2019. The experiment was conducted in Randomized Block Design. Different morphological indices were observed (plant height, number of branches, dry matter, number of pods) and yield attributes and yield of groundnut VRI-2 was recorded. The heat unit concept of Growing Degree Days also worked out for individual sowing windows. Among the sowing dates, 05.01.2019 recorded essential GDD of 1651.3°C and higher growth attributes, yield attributes and yield (2370 kg ha-1).