The exploitation of cashew under irrigated conditions has been very promising, especially in the state of Ceará, however, the response of this crop to the water regime depends on the genotype. This work attempts to compare the physiological and biochemical responses (content of organic and inorganic solutes and gas exchange) and yield of precocious dwarf cashew (Anacardium occidentale L) plants under two water regimes (irrigated and rainfed). The experiment was conducted at the experimental field of Embrapa Agroindústria Tropical, in Pacajus, Ceará, from August 2006 to January 2007. The plants were subjected to two treatments: without irrigation and another irrigated with water with electrical conductivity of 0.5 dS m-1. The physiological responses were assessed monthly and the production data were obtained from November to January. The levels of N-aminosoluble and proline in the leaves of plants grown under dry farming conditions were higher than in irrigated, but no significant difference was found between treatments for gas exchange, soluble carbohydrates, K+, Na+ and Cl-. However, except for photosynthesis, all the variables showed changes in collection times. Despite changes in some variables during the experiment, the yield of plants was not affected by water stress.
Anacardium occidentale; water stress; productivity; gas exchange