Population, Growth and Water Use of Groundnut Maintained on Stored Water. III. Dry Matter, Water Use and Light Interception

Abstract

SUMMARYAt a field site in central India, four populations of groundnut (Arachis hypogaea L.) were grown on stored water to investigate how the production of shoot and root dry matter is related to transpired water and intercepted radiation. Throughout the season, total dry matter was closely related to transpiration (slope = 3.0 mg dry matter g−1 water) and the amount of radiation intercepted by foliage (slope = 0.74 g dry matter MJ−1 radiation intercepted). Accumulated transpiration increased linearly with intercepted radiation at 0.37 kg water MJ−1 in the sparser stands. In the densest spacing, the initial slope of the relation at 0.28 kg MJ−1 decreased later in the season because water deficits curtailed growth without a concomitant reduction in the interception of radiation.