Effect of tree planting density and cultivar on sweet cherry growth onto the edabriz rootstock at four locations in the north and centre of Portugal

Abstract

The growth of sweet cherry cultivars Regina, Skeena and Sweetheart was evaluated when grafted onto the Edabriz rootstock and at four planting densities. The trial was set on March 2003 at four locations in the North and Centre of Portugal, with two replications in Caria, Vila Real and Alcongosta and three in Carrazedo de Montenegro. Within row spacing is approximately 5,0 m and plant spacing along the row is 0.7, 1.4, 2.1 and 2.8 m, corresponding to densities of 2600, 1300, 860 and 650 trees/ha, respectively.

The trunk diameter of every plant was measured each year and trunk cross sectional area (TCSA) was calculated. At the end of the second leaf stage, significant differences in growth were already observable, concerning both trial location and plant density. The sweet cherry trees of the C. Montenegro trial grew 76, 36 and 9% more than those of Alcongosta, Vila Real and Caria, respectively, thus trial location accounted for 25% of the expected total variance. Plant density corresponded to 3% of the total variance, and the trees at 0.7 m grew 22% less than those the furthest apart. Results show that cultivars grew poorly when grafted onto this rootstock in Alcongosta and Vila Real. Therefore, in analogous situations, it is important to adjust water and nutrient supply to the specific requirements of the rootstock, so as to better manage vegetative growth and to prepare the trees for their major role: fruit yielding.