02191naa a2200193 a 450000100080000000500110000800800410001910000160006024501420007626000090021852016190022765000120184665000130185870000200187170000180189170000170190970000180192677300530194420624962017-02-08 2016 bl uuuu u00u1 u #d1 aCRUZ, J. L. aElevated CO2 concentrations alleviate the inhibitory effect of drought on physiology and growth of cassava plants.h[electronic resource] c2016 aDue to the rise in anthropogenic greenhouse gas concentrations, the earth's climate is expected to change, with precipitation being reduced in some areas resulting in growth-limiting drought and, as a consequence, reduced plant productivity. We investigated the physiological and growth responses of cassava (Manihot esculenta Crantz) to approximate present-day ambient (390 ?L L?1) and elevated (750 ?L L?1) atmospheric CO2 concentrations under well-watered and water deficit conditions, aiming at understanding how cassava would face those problems. Water deficits led to reductions in the Leaf Elongation Rate of plants grown at ambient as well as CO2-enriched concentrations. However, plants grown at 750 ?L L?1 of CO2 maintained leaf growth two days longer than plants grown at 390 ?L L?1. Three Days After Withholding Water (DAWW), photosynthesis and stomatal conductance were reduced in plants grown under ambient CO2, while in plants under an elevated CO2 concentration, these physiological functions remained similar to that of control plants grown under good water availability. Five DAWW plants grown with 750 ?L L?1 continued to have enhanced gas exchange compared with plants grown under 390 ?L L?1. Under drought stress, the instantaneous transpiration efficiency was always greatest for plants grown under elevated CO2. The positive response of elevated CO2 levels on total dry mass was 61% in the water-stressed plants and only 20% for the plants grown under good water availability. Stomatal limitation was an important factor reducing CO2 assimilation in cassava growing under drought conditions. aCassava aMandioca1 aALVES, A. A. C.1 aLECAIN, D. R.1 aELLIS, D. D.1 aMORGAN, J. A. tScientia Horticulturaegv. 210 p. 122?129, 2016.