Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/28/2008
Publication Date: 7/15/2008
Citation: Felicetti, E., Zhu, Y., Mattheis, J.P. 2008. Ascorbic Acid Profiles in 'Delicious' and 'Honeycrisp' Apples During on-Tree Development and Cold Storage. Meeting Abstract.
Technical Abstract: Reactive oxygen species (ROS) produced in plants are involved in a number of processes both beneficial (signal transduction) and detrimental (induction of physiological disorders). ROS toxicity can be ameliorated by a number of metabolic systems or compounds in plant tissue including L-Ascorbic acid (AsA, Vitamin C). ‘Honeycrisp’ apples, prone to softscald, soggy breakdown, and bitter pit, and ‘Delicious’ apples, resistant to these disorders, were used as model systems to examine AsA dynamics during on-tree development and cold storage (CS). AsA content was analytically characterized using HPLC and a AgNO3 histochemical staining technique. Fruit was harvested prior to, including, and following physiological maturity. Fruit at physiological maturity was held in CS, and tissue was collected monthly for six months. Several characteristics were consistent throughout development and storage. AsA content in peel was higher than that in cortex for both cultivars. ‘Honeycrisp’ had more AsA than ‘Delicious’ in both cortex and peel. There was no statistical relationship between AsA content and developmental stage/storage duration in ‘Honeycrisp’ cortex, possibly due to the non-homogenous distribution of AsA as visualized by Ag staining. More intense staining in ‘Honeycrisp’ as compared to ‘Delicious’ was consistent with the analytical results. The ‘Delicious’ staining pattern indicated AsA is distributed nearly uniformly throughout the apple but becomes localized to the peel, endocarp, and core line as development progresses; during storage AsA is localized to the endocarp and core line. The AsA pattern for ‘Honeycrisp’ was much less homogeneous during on-tree development. Staining intensity decreased during the first 3 months storage then increased thereafter. The same pattern for stored fruit exists in the analytical results. A correlation between AsA content and post-storage quality was not apparent for either cultivar.