Abstract

An experiment was performed to evaluate the effect of gibberellic acid (GA₃) on seed size and sprouting of potato (Solanum tuberosum L.). The experiment was laid done in factorial design (3 × 3) using Agria, Marfona and Draga cultivars and three concentrations of GA₃ (0, 5 and 10 mg/lit). Results showed that application of gibberellic acid at low concentrations (5 and 10 mg/lit) was able to increase general performance and productivity of seed tubers of potatoes. Seed tuber production was increased by application of using gibberellic acid in all cultivars. Total weight of seed tubers produced by application of 5 mg/lit GA₃ was statistically different compared to control (p ≤ 0.05). Also, results showed that after one week from application of GA₃, starch content decreased and total content of sugar increased in potato tuber. The tubers treated with GA₃sprouted earlier while in control sprouting was very late and slow. Furthermore, we indicated that sugar content is one of the important parameters determining the sprouting of seed potatoes. Thus the sequence of events can be summarized as: Application of GA₃ → Starch hydrolysis → Decrease of starch content of tubers → Production and increase of total sugar content → Dormancy breaking → Tuber sprouting.

Key words: Potato (Solanum tuberosum L.), gibberellic acid (GA₃), tuber size, tuber sprouting.