Influence of applied lysophosphatidylethanolamine on fruit quality in Thompson Seedless table grapes

Abstract: The effect of foliar applications of lysophosphatidylethanolamine (LPE) on 'Thompson Seedless' (Vitis vinifera L.) was evaluated to determine the suitability of this plant amendment aid as a management tool in table grape production. LPE at 10 mg L^-1 was sprayed on vines at two different stages of berry growth and development. Treatments were: 1) 4 weeks after fruit set; 2) 6 weeks after fruit set; and 3) 4 and 6 weeks after fruit set. Soluble solids content (SSC) of berries at all harvest dates was significantly higher for vines treated with LPE compared to the control. Titratable acidity (TA) gradually decreased during ripening, and by the third harvest, TA of berries from vines treated with LPE was lower than that of control. All the treatments resulted in higher fruit firmness when compared to control. However, there were no significant differences in firmness of berries from vines given LPE treatment at different stages of growth. LPE treatment increased berry size, although no significant difference in size between single and sequential applications of LPE was observed. These results indicate that LPE may play a role in plant hormone-associated regulation of berry growth and development.