Ecophysiological response to irrigation of two olive cultivars grown in a high-density orchard

High-density oliveculture system needs irrigation and introduces new cultivars in new environments. So the evaluation of varietal ecophysiological response to irrigation is a crucial topic. For this reason it was planned a research on two cultivars, Coratina and Arbequina, trained according to high-density system. In 2009 the irrigation was conducted according to the conventional management by applying an irrigation frequency of 4 days. The leaf water potentials reached values similar to the limits reported for the recovery within 48 hours. However, plants showed a leaf water status and gas exchange recovery just after 24 hours from watering. The results highlighted some varietal differences: Arbequina showed a better response to irrigation, while Coratina performed a higher water use efficiency by a lower leaf transpiration.

Sprouts seasonal elongation of two olive cultivars in a high-density orchard

The new high-density cropping systems (>1200 trees ha-1) represent a very interesting proposal for olive orchard profitability. It is crucial to know the morphology and the dynamics of sprout elongation of a cultivar in order to fully assess its suitability for a high-density olive orchard. For this reason we planned a research on two cultivars, Coratina and Arbequina, in a high-density orchard. The apical sprouts elongation of Arbequina early stopped at fruit set without a further step, while Coratina showed a little growth flux after pit hardening. Similar trends showed the lateral proleptic sprouts. Only the sylleptic sprouts of both cultivars had a second period of activity. In all cases, the sprouts elongation finished at the end of summer, when oil accumulation started. Coratina showed higher apical shoot growth and internodes mean length than Arbequina. On the contrary, Coratina showed lower lateral proleptic shoot growth and nodes number than Arbequina, but the same internodes mean length. No significant differences were observed between cultivars for growth, nodes number and internodes mean length of sylleptic shoots. The differences observed between the two cultivars could be explained considering their different vigour. The introduction of this innovative cropping system is allowed to register a considerable reduction of production costs. The result is a considerable increase in the economic performance of the olive grove and a consequent reduction in the unit cost for kg of oil. These data are very useful for varietal choice and field management in high-density orchards and then for new olive breeding programs.