TOMATO CROP BEHAVIOR UNDER 4 WATER REGIME S

In order to evaluate the effect of four irrigation regimes for tomato (Lycopersicon esculentum Mill.), an experiment was carried out in a ra ndomized block design with four treatments and eight replication at th e Experiment Station of the Middle - North Research Center (Centro de Pesquisa Agropecuaria do Meio-Norte) of EMBRAPA, at Pamaiba, PI, Brazi l. The treatments were the irrigation regimes defined by four differen t levels of Class A evaporation pan multiplied by the factor whose val ue was given according to the crop development. In absolute values, re gime 4 showed the highest productivity concerning total yield (84.79 t /ha), commercial yield (75.62 t/ha) and great fruits (34.62 t/ha). Reg imes 1, 2 and 3 showed total yield between 74.48 and 75.75 t/ha, and y ields of commercial fruits between 65.72 and 69.07 t/ha. Regime 4 show ed the smallest water use efficiency. Regime 1 showed the best water u se efficiency but a little different from regime 2 and 3. In economica l terms, regime 4 was the most viable to be used, overcoming regime 1 net income in 17.98%.