POSTHARVEST NITROGEN APPLICATION EFFECT ON OVULE LONGEVITY OF COMICE PEAR TREES

Low fruit set and cropping are common characteristics of 'Comice' pear (Pyrus communis L.) trees in spite of a high bloom density. An experim ent was conducted to study the effect of late season nitrogen (N) appl ication on ovule longevity of this cultivar. Mature trees were given a single foliar application of 0% (control), 5%, or 10% (w/v) aqueous u rea immediately after hat-vest. Ovule senescence was detected by fluor escence microscopy. Ovule longevity was extended and fruit set was inc reased by fall urea. Flower density and fruit fresh weight were not af fected.