Effects of gibberellic acid on germination percentage, growth and yield of Jerusalem artichoke

Abstract

Importance of work: The dormancy of Jerusalem artichoke seed tubers is a major obstacle to breeding progress and production.
Objectives: To examine the effect of gibberellic acid (GA) on the dormancy of Jerusalem artichoke tubers.
Material & Methods: Four GA concentrations (0%, 0.03%, 0.10% and 0.50%) and two varieties of Jerusalem artichoke (JA 89 and HEL 65) were assessed in separate 2×4 factorial experiments using a randomized complete block design and four replications.
Results: Application of GA at the 0.03% concentration had the highest tuber germination percentage, seedling height, seedling diameter, seedling dry weight, tuber fresh weight, tuber dry weight, total dry weight and harvest index in both the Jerusalem artichoke varieties. Application of GA at the 0.03% concentration resulted in uniform germination of both varieties within 7 d after planting. However, GA application at 0.10% and 0.50% concentrations decreased the germination percentage, growth parameters and yield of Jerusalem artichoke, possibly due to toxicity at high concentrations.
Main finding: GA at 0.03% concentration was the most effective at breaking seed tuber dormancy and increasing the growth and yield of Jerusalem artichoke.