Consumo hídrico da videira Festival sob intermitência de irrigação no submédio São Francisco.

Abstract

This study was conducted in the Experimental Field of Bebedouro, belonging to the Company Brazilian Agricultural Research Institute (Embrapa Semi-Arid), located in the Irrigated Perimeter of Bebedouro, Petrolina-PE, aiming to determine the water consumption and the coefficient of culture of the vine (Vitis vinifera, L), variety Festival, seedless, three years old, for eight phenological stages: 1. sprouting period; 2. vegetative development; 3. pre and full bloom; 4. first stage of fruit growth; 5. stop of growth of the fruit; 6. second stage of fruit growth; 7. final maturity of the fruit and 8. phenological rest, during two production cycles, using two different methodologies: Energy balance by the Bowen-BERB ratio, applied to the "crown-soil", "crown" and "surface soil "and soil water balance - BHS, covering four cycles of intermittent irrigation (1, 2, 3 and 4). Among the obtained results, we highlight: a) The subdivision of the system "copasolo" in two distinct subsystems "canopy" and "soil surface", provided the obtaining of values ​​of culture coefficients practically equal to those obtained by means of the energy ratio by the classical Bowen ratio, besides the advantage of providing coefficient values crops for the vine canopy, as well as for soil evaporation; B) It was found that the values ​​of the vine crop coefficients, determined on the basis of the water balance in the soil for intermittent irrigation at level four, exceeded the estimated for the other intermittency, in almost all their phenological stages and tended to decrease, as the number of coefficients obtained for level one flicker, presented as the lowest; W) It was verified that the values ​​of the estimated grapes cultivation coefficients, by the the Bowen ratio, were much higher than those estimated by means of the BHS, only during the phenological stages with lower soil and practically the same in almost all the other stages; d) It was found that the increase of the number of irrigation intermittences led to a significant reduction of water by deep percolation. That is, the reductions obtained in relation to the control were order of 20.46, 46.26 and 79.80%, corresponding to the intermittency of levels two, three and four, respectively, for two production cycles; e) It was found that the ETc values grapes, determined by the modified energy balance, were of the order of 496.87 and 472.81 mm, corresponding to the 1st and 2nd cycles, respectively, while the value estimated by means of the soil water balance for the 1st cycle, oscillated around 435.35 + 32.06 mm. However, in the 2nd cycle this type of comparison was severely impaired by the occurrence of excessive rains.