Growth and photosynthetic gas exchange characteristics in Solanum aethiopicum under water stress in organic production system

Abstract

Water stress is one of the challenging problems faced by agriculture. More often, crop growth and yield fails when exposed to water stress. However, water requirement is crop specific, they tend to develop own defense mechanism to combat the stress. It is highly imperative to study the response of plant to water stress. The present was carried out to evaluate the effects of different levels of water on growth and gas exchange parameters of Solanum aethiopicum and Solanum macrocarpon. Plants were grown at different level of water viz. 100% PC (pot capacity), 75% PC, 50% PC and 25% PC. Parameters like leaf number, leaf area, plant height, plant spread, shoot dry weight, chlorophyll content, photosynthetic rate, transpiration rate, stomatal conductance were reduced with reduced in water levels, however, Solanum aethiopicum performed normal even at 50% PC which was at par with plants at 75% PC, though there was significant difference from 100% PC. All the levels of water showed significant differences on root dry weight, root shoot ratio and water use efficiency and similar trend in all studied parameters was found in S. macrocarpon. Major finding of the study was non-significant differences in fruit yield at three levels of water i,e 100, 75 and 50% PC in S. aethiopicum, which infers the possibility of growing S. aethiopicum at reduced level of water. However, S. macrocapon, on the other hand, could not sustain its growth due to water stress. Detail studies on crop physiology and the mechanism of drought tolerance in S. aethiopicumcan be explored to establish more facts.