Relationship between vegetative growth and fruit production in olive cultivar characterized by different vigour

The intensification of olive cultivation has been pushing researchers toward the individuation/obtainment of genotypes characterized by low vigour and early yield. This makes very important to increase the knowledge on factors which affect the vigour in olive. One of this factor is represented by fruit production. It is known that yield has a negative relationship with vegetative growth, but there are not data about the quantification of this relationship. Therefore, the present study was carried out in order to quantify this relationship. In 2014 and 2015, in one year old trees (in 2014) of the cultivars Arbequina, known as a low vigour variety, and Frantoio, known as a high vigour variety, the effects of yield on tree growth was studied by comparing trees that were left to produce and trees on which the production was impeded by eliminating the inflorescences before flowering.The trees were grown in pots with fully provision of water and nutrients. In both the considered years the shoots vegetative growth and yield were evaluated. Moreover, at the end of 2015, an analysis of the growth of the trees was carried out by subdividing them in the different constitutive parts (roots, collar, main axe, branches, shoots and leaves) and by drying and weighing them. The results showed that the trees of Arbequina on which the production was impeded by eliminating the inflorescences had a vegetative growth (evaluated by weighting all the vegetative organs of the trees) similar to that of Frantoio. The implications of the obtained results on the relative importance of fruiting among the factors known to affect the vigour of the trees in olive is discussed.