ISHS Acta Horticulturae 293: IX International Symposium on Apricot Culture
FLOWER BUD ABSCISSION AND MALE STERILITY IN APRICOT |
| Authors: | M.C. Medeira, M.E. Guedes |
| Abstract:
Irregular yields of some apricot cultivars result mainly from high flower bud abscission. Histological and ultrastructural observations in flower buds during rest suggest a metabolic disturbance, related to abnormal secretory process. Electron dense inclusions in the vacuoles and in the cytoplasm of sporogenous cells seem related to the degeneration of mitochondria, by middle November. The occlusion of some vessels in vascular bundles of the receptacle, as well as disruption of parenchymatic cells, adjacent to vascular bundles seem to be the first alterations leading to bud abscission. We have not detected any pathogens in flower buds and in their axis tissues. Partial male sterility in apricot cv. CNEFFC results from abnormal cytokinesis following telophase II, mistiming in tapetum degeneration, failure in dissolution of the primary cell walls of meiocytes and tapetum. The extent and frequency of this developmental irregularities varied both between and within locules of single anthers. Abnormalities in the formation of pollen walls are described and may be related to a deficient secretory function of the tapetum. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
