Respostas fisiológicas de <i>Theobroma cacao</i> L. submetidas ao alagamento por longos períodos

The aim of this study was to evaluate the physiological responses of cocoa plants (Theobroma cacao L.) subjected to water stress under flooding in different periods. The study was conducted in a greenhouse at the Capixaba Institute for Research, Technical Assistance and Rural Extension (INCAPER), located in Linhares-Es. The cultivars used for Theobroma cacao L. were cocoa varieties CCN 51 and TSH 1188, the first being used as a scion and the second as a rootstock. The experiment was carried out with cocoa seedlings under stress in a flooded environment, arranged in buckets and submerged in water, under different time conditions. Readings were taken at 0, 1, 2, 4 and 8 days of flooding. Measurements of net CO2 assimilation, stomatal conductance, transpiration and water use efficiency were performed, all using IRGA. The treatment 2 days after flooding did not differ from the control treatment (without flooding), while in the treatment 4 DAA there was a reduction in the net CO2 assimilation content. Plants flooded for 8 days showed lenticel growth, showing an attempt to alleviate environmental conditions. There was no interference by flooding in the PI and PII photosystems; the photosynthetic apparatus remained stable.