Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia
Water deficit places major limitations to plant productivity and it’s a factor to be taken into
account in agriculture due to the global climate changes. In this work the main physiological
and biochemical strategies involved in Jatropha curcas L. responses to water deficit were
studied. Photosynthesis and stomatal conductance presented a significant decrease under
water stress. With the increase of drought intensity non-stomatal limitations toke more
importance than stomatal limitations. After soil rehydration those parameters showed a
complete recover. A greater tolerance to oxidative stress induced by water deficit is
suggested by the increase in superoxide dismutase and catalase activity. Chlorophyll content
decreased significantly with drought stress but plant seems to be able to regenerate it after
soil rehydration. Under water deficit amino acids and proteins decreased significantly. Lipid
peroxidation significantly increased with drought stress conditions that can lead to damage in
cellular compound caused by the increase of the ROS formation. Jatropha curcas L. plants
demonstrated some resistance to water deficit and capacity to fight oxidative stress, using
metabolic strategies to increase plant tolerance against oxidative damage.
