Daminozide Control of Globe Artichoke Flower Head Atrophy

Abstract

Atrophy of the terminal flower heads in globe artichoke, Cynara scolymus L., occurs when the growing season is characterized by hot temperature during apical bud transition and differentiation. Atrophic heads show total or partial lack of florets on the receptacle, which consequently appears completely or partially necrotic. Butanedioic acid mono-(2,2 dimethylhydrazide) (daminozide) was sprayed on plants at rates up to 8000 ppm, during a 4-year field trial. When applied about 10 days before bud transition begins, daminozide reduced the incidence of atrophic terminal flower heads. Best results were obtained with daminozide applied at 4000-5000 ppm during periods when temperatures exceed 25°C. Rates higher than 5000 ppm and temperatures lower than 25°C delayed head production.