4915
HOSSAM AHMED HASAN EL-ATTAR
USE OF SOME LOOSENING AGENTS TO FACILITATE MECHANICAL HARVESTING OF OLIVE FRUITS
Olive, Koroneiki, Loosening agents, Mechanical harvesting, Ethephon, MPK, Phosphoric acid and Thiourea.
This work was carried out in a private orchard located at Cairo – Alexandria, desert road (50 Km from Cairo), Egypt during three successive seasons 2010, 2011 and 2012 .The present study aimed to facilitate mechanical harvesting of fifteen - years - old "Koroneiki" olive (Olea europaea L.) trees. Trees were sprayed with chemical loosening agents: ethephon (2-chloroethylphosphonic acid) at the concentrations of 300, 600 and 1200 mg/ l, mono potassium phosphate (KH2PO4) MPK at 2%, 3% and 4%, phosphoric acid (H3PO4) at 75, 125 and 175 mM and thiourea (1,3-di 3-Methoxybenzyl) at 500, 1000 and 1500 p.p.m. in two times for each concentration (7 and 15 days before harvesting) then harvested by a mechanical hand vibrator by pass it over the treated branches either with the different loosening agents or with water only (control). Generally, spraying of any fruit loosening agents before the mechanical harvesting process by 15 days was better than use by 7 days in facilitating harvesting by help in making abscission zone in the fruits‟ pedicels. Inspite of applying a high ethephon and phosphoric acid concentrations on trees 15 days before harvesting greatly enhanced leaf drop percentage, leaf and fruit burns percentage , also decreased fruit removal force (FRF), no significant differences in oil content, peroxide number and iodine value were noticed among all treatments, but with an exception that spraying phosphoric acid 15 days before harvesting had raised oil acidity percentage. Ethephon at 1200 mg/l had led to the highest significant abscissic acid (ABA) contents while spraying 175 mM of phosphoric acid had maintained the highest significant pectinase activity rates, in spite of that, ethephon sprays at 1200 mg/l in both dates, 7 and 15 days before harvesting, had scored the highest significant cellulase activity. In addition, both of ethephon at 1200 mg/l and 175 mM of MPK applied in both dates were dramatically caused olive fruit dropping, also they produce comparatively similar anatomical mode of effects. As the symptoms of abscission was found in all tissues shared in pedicel internal structure. A partial budget, for applying the mechanical harvesting, was held including the items that increase or reduce income. A positive net was calculated and indicated that orchard income will increase due to apply the mechanical harvesting and it is recommendedto apply this change.
2015
Ph.d
Cairo
Agriculture