Effect of ethephon on time of olive oil (cv. Zard) harvesting

Removing fruit from the olive tree is a major problem in both oil and table olive harvesting. Quality and economy of the oil olive production relies largely on determining the appropriate time and method of harvesting. In order to specify the suitable time of Zard oil cultivar harvesting, research was conducted at Tarum Olive Research Station in Zanjan Province in Iran in 2010. A randomized complete block design experiment was used with three methods of harvesting, namely a(1), pneumatic comb machine, a(2) branch shaker (hand machine) and a(3) hand harvesting (hand picking). In all three methods of harvesting ethephon chemical was used as an abscission agent in three concentration levels as b(1), 0, b(2), 2000 and b(3), 4000 ppm. Ethephon had a significant effect on fruit detachment force reduction. This force decreased with the time of removing. The best time for removal was in middle of November. The results also showed that leaf drop was higher for the treatment with an ethephon concentration of 4000 ppm versus lower concentrations. Leaf drop of pneumatic combs was higher than in other harvesting methods.