Soil flooding can induce changes in cell metabolism and cause deviations in optimum conditions for plant growth, creating a stress condition. The objective of this work was to evaluate the effects of flooding on growth and mineral nutrition of six T. cacao clones (CP-49, CCN-10, CP-06, CEPEC-2007, CEPEC-2008 and PS-1319), aiming to clarify the possible mechanisms of soil flooding tolerance. Plants of T. cacao with 6 months of age were subject to soil flooding, along with the control treatment (not flooded), for 30 days. At the end of the experiment, flooding induced decreases in the root growth rates (except for CP-06) and leaf area, increases in the dry mass, in the stem relative growth rate (except for the clones CP-06 and CEPEC-2008), in the net assimilation rates (except for PS-1319) and in the specific leaf mass of the clones CP-49, CCN-10 and CP-06. Plants that survived the 30 days of flooding also presented low values of the leaf area ratio. In general, substrate flooding has caused disability in the absorption of macro and micro nutrients, with exception for Fe. Among all clones evaluated, CP-49 was considered as tolerant and CEPEC-2008 as non-tolerant to soil flooding. The other clones are in an intermediate position. Therefore, the clone CP-49 presents a great potential to be cultivated in flood prone environments.
anoxia; cocoa; plant growth; abiotic stress; plant nutrition
