USE OF GIBBERELLIC ACID TO HASTEN FLOWERING IN RUTABAGA

Abstract

In field conditions, rutabaga (Brassica napus ssp. Rapifera (Metzg.) Sinsk.) plants are biennials and require exposure to low temperature for completion of their life cycle to seed production state. When young rutabaga plants were thermoinduced (3–5 °C) for 8 wk and subsequently transferred to growth room conditions, formation of flower buds resulted in 6 wk. Flowering response was greatly enhanced if the plants were sprayed with GA3 (100 mg/L) prior to thermoinduction. Compared with untreated plants, the GA3-sprayed plants responded with flower bud formation after as little as 3 wk of cold treatment. A longer cold exposure (6–8 wk) of the GA3-sprayed plants resulted in rapid development and maturity of the inflorescence. This note emphasizes the pharmacological role of gibberellins as regulators of flowering and their usefulness to enhance seed production and plant breeding programs.