Strawberry fruit quality attributes after application of plant growth stimulating compounds

Strawberry plants cv. Camarosa were treated with different plant growth stimulators, in order to examine their effect on both yield and product quality. The treatments comprised an untreated control and a mixture of a seaweed extract plus a commercial mixture of nitrophenolates and a commercial mixture of an auxin (phenothiol) plus gibberellic acid at two dose rates. The plant growth stimulators increased marketable yield and fruit size, while they had no significant impact on fruit juice pH, titratable acidity and total soluble solids concentration. Furthermore, they had no significant effect on fruit organic acid and carbohydrate concentration and on fruit color, although they enhanced total anthocyanin concentration. The antioxidant activity of the fruit juice was slightly higher in the fruits of control treatment, which could be the result of their higher total phenol, o-diphenol, flavonoid and flavanol concentration. When a taste panel took place, the panelists gave the best score to those fruits deriving from plants treated with the mixture of auxin plus gibberellic acid.