Effect of Flooding Under the Gas Exchange of Cocoa Seedlings

Under flooding conditions, plants exhibit morphological and physiological characteristics that indicate that the plant is undergoing stress. In this sense, the objective of this work was to evaluate the gas exchange of cocoa (Theobroma cacao L.) seedlings submitted to different times of flooding. The study was carried out at the experimental farm of the Capixaba Institute for Research Technical Assistance and Rural Extension, in Linhares, North of the State of Espírito Santo, Brazil. The experimental design was completely randomized. The treatments consisted in the flooding of the seedlings on days 0 (without flooding), 1, 2, 4 and 8. The seedlings were evaluated for gas exchange by characteristics: liquid assimilation of CO2; stomatal conductance; transpiration rate; water use efficiency. The gas exchange of cocoa seedlings were influenced by the flooding period in which they were submitted with a decrease in the values liquid assimilation of CO2, stomatal conductance and transpiration rate after the fourth day of flooding, after this period the seedlings developed morphological modifications that allowed them to adapt the flooding conditions, improving the liquid assimilation of CO2.