FRUIT SET PATTERN IN SELF- AND OPEN-POLLINATED OLIVE CULTIVARS

Ovary and fruit abscission in postanthesis in self- and open pollinated trees of ‘Moraiolo’, ‘Frantoio’ and ‘Manzanilla’ were monitored from 4 to 45 days after full bloom (FB) when abscission ended. Fruit set was higher in self- than in open pollinated treatments for all cultivars until approximately 25 days after FB (FB+25). However fruit set in response to self- or open pollination by FB+45 differed from both set at FB+25 and previous reports. A general survey of the response of a large number of cultivars to self- and open pollination was made at FB+15 and FB+45 in 1987, 1988 and 1989. In all three years (with different postanthesis temperature) overall higher set in self- than in open pollination was found in most varieties at FB+15. However by FB+45 this response varied according to variety and year. The possible causes of these responses are discussed.