(384) Raisin Production of `Fiesta Seedless' on Freedom Rootstock under Different Plantation Densities

Grape is one of the more important crops in northwestern Mexico (Sonora), especially for table grape. Although raisin production is a good option, it must be efficient and productive due to the problems of shortage and high cost of water, salinity, and nematodes. The objective of this research was the evaluation of `Fiesta Seedless' on Freedom rootstock for raisin production with different plantation densities. This study was carried out in the INIFAP Caborca research station in 2002. Four plant separations (1.0, 1.5, 1.7, and 2.0 m) were evaluated on furrows 4 m apart. Plants were grafted on Freedom rootstock in 1999. We also considered a control treatment (4 × 2 m on its own feet) and fertilized it with 80N–60P–80K. All experiments were carried out under the espalier training system with double crossbeam; watering was under a drip-irrigation system; and the statistical design was completely randomized. Statistical differences between the evaluated spacings were not observed, but all densities surpassed the control. Greatest yields were obtained with 1.5- and 1.7-m spacings, at 6.1 and 6.0 t·ha -1 of raisin, respectively, which were 2.2 t·ha -1 more than the control (3.8 t·ha -1 ). There were no differences in sugar content and harvest time, since all treatmens, including the control, were harvested at 24 °Brix. Freedom rootstock had 100% nematode control, 30% less water consumption, and was not fertilized.