|KIM, JOONYUP - University Of Maryland
Submitted to: Stewart Postharvest Review
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/28/2015
Publication Date: 6/1/2015
Publication URL: http://handle.nal.usda.gov/10113/61611
Citation: Tucker, M.L., Kim, J. 2015. Abscission, organ separation, is more complex than you might think. Stewart Postharvest Review. 11:1-7.
Interpretive Summary: Abscission, organ separation, is a cell separation event that occurs in a finite layer of cells at the base of an organ, e.g. leaf, flower, fruit, petals, etc. We present a brief overview of what we have learned about abscission in recent years as it relates to what we’ve learned about abscission over the past century, and also what we still need to work on. Abscission is an important separation process that affects crop yield, fruit quality and ease of harvest. Artificial control of abscission through chemical applications and genetics has the potential to significantly increase and improve agricultural productivity.
Technical Abstract: Abscission, organ separation, is an integral part of the life of a plant. Natural and artificial regulation of abscission can have substantive effects on crop yield and fruit quality. It’s been nearly 100 years since the discovery that ethylene played a role in abscission and more than 50 years since the discovery that auxin played a role. As more hormones were discovered – cytokinins, gibberellins, abscisic acid and jasmonic acid – each has been demonstrated to have at least some effect on the timing of abscission. Auxin is of particular interest because it plays a role in cell differentiation and competence to abscise as well as initiation and control of cell separation. Synthesis of a protective layer at the site of organ separation is common to most abscission processes but may be regulated separate from cell separation. Study of Arabidopsis floral organ abscission has stimulated many new lines of research including work on the signaling peptide Inflorescence Deficient in Abscission (IDA) and a abscission-specific change in cytoplasmic pH that correlates with the process of cell separation in Arabidopsis. The discovery that several genes associated with formation of organ boundaries in plant meristem are expressed in mature abscission zones may provide clues to the differentiation of abscission zone cells.