VASCULAR CONNECTION AND OTHER FACTORS THAT INFLUENCE APRICOT BUDS DROP

Abstract

The vascular connection of apricot ‘Donra’ and ‘CP-90-5C’ selection buds during dormancy and the start of budding were studied. The observations of the xilema vascular connection throughout the structure of the floral bud were normal, reaching each ventricle of the flower verticilo of the flower; not only was the xilema observed, but also the phloem. The apricot ‘Donra’ had a high loss of floral buds under the weather conditions in the state of Mexico, which the CP-90-5C selection had irregular production due to floral bud drop. The observations of both apricots determined that the reproduction structures (pistil and anthers) were damaged during dormancy; this damage seems to be a sign that stimulates the abscission layer at the base of the buds which always occurs in the same site. The abscission of the buds was not immediate. Rather, they remained adhered in most cases until the start of the vegetative budding which strongly accelerates the bud dropping. Anther and/or pistil necrosad were most common during December, especially in the apricot ‘Donra’.