Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: April 5, 2004
Publication Date: December 15, 2004
Citation: Lulai, E.C. 2004. Potato tuber suberization [abstract.] American Journal of Potato Research. 82(1):79. Technical Abstract: The intact suberized layer of the tuber periderm provides a durable barrier that is resistant to bacterial and fungal infection. Rapid healing, i.e. suberization, of the various kinds wounds inflicted on tubers during harvest, handling and seed cutting is essential to restore this barrier to infection. Despite the economic importance of wound-healing to agriculture and the consumer, there are large knowledge gaps concerning the induction, biosynthetic processes, and the regulation of suberization as well as the role(s) of the suberized barrier in the periderm. Progress addressing these knowledge gaps is presented. A waxy water vapor barrier quickly forms at the wound site to reduce water vapor loss, apparently before appreciable suberin accumulates. Two structurally distinct biopolymers (polyphenolic and polyaliphatic) differentially accumulate on cell walls neighboring the wound site to form what is collectively known as suberin. These accumulations occur first on existing cell walls to form a suberized closing layer and later on phellem cell walls formed by the meristematic action of a newly created phellogen. The accumulations of these two biopolymers on the suberizing cell walls result in resistance to bacterial and then fungal infection. During suberization, environmental conditions must be controlled to prevent oxygen depletion and guard against increased carbon dioxide concentrations, both of which impede suberization. High relative humidity must be maintained to prevent dessication and death of suberizing cells at the wound surface. Advancing our knowledge of the biochemical and molecular mechanisms of suberization is a requisite for the development of technologies needed to hasten wound-healing and ultimately improve quality and profitability for the potato industry and the consumer.