EFFECT OF PECTIN OLIGOMERS ON STRAWBERRY FRUIT DECAY AND ETHYLENE PRODUCTION

Authors: Baldwin, Elizabeth - Liz; Narciso, Jan; Cameron, Randall - Randy; Plotto, Anne

Submitted to: American Society of Horticulture Science Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/16/2006
Publication Date: 6/1/2006
Citation: Baldwin, E., Narciso, J., Cameron, R., Plotto, A. 2006. Effect of pectin oligomers on strawberry fruit decay and ethylene production. HortScience. 41(4):1044.

Interpretive Summary:

Technical Abstract: Strawberry fruit were harvested on three different dates from the Strawberry Association plot (cv. Festival), a commercial farm (cv. Camino Real) and at the University of Florida Gulf Coast Research and Education Center (cv. Sweet Charlie), in Central Florida 2005 and 2006. Fruit were transported to the USCSPL in Winter Haven, FL, sorted, dipped for 10 s in treatment solutions, drained and stored in commercial clam-shells at 15-19 °C. Percent decay (number of fruit with lesions) was monitored during storage. There were 10 fruit per replicate clamshell, and 3-4 replicates per treatment for each harvest. Treatments included three size-classes of galacturonic acid (GA) oligomers with a degree of polymerization (DP) ranging from 1-13, 8-24, and 22-46 and undigested polygalacturonic acid at 0.2% in 50 mM LiOAC, 50 mM LiOAC/NaOAC, with 22% ETOH, or KOAC buffer (all buffers at pH ~ 4.4), prepared by enzymatic digestion followed by differential pH and alcohol precipitation. The main pathogens found on these fruit were Rhizopus stolonifer and Botrytis cinera at 1x105 cfu/g fruit in 2005 and 5x107 in 2006. The medium range oligomers (DP 8-24) reduced decay significantly compared to buffer alone or to the lower or higher DP GA oligomers, and elicited ethylene production. Oligomers in this pectin size class have previously been reported to elicit ethylene and plant defense responses in plant tissues.