Rootstock effects on responses of potted ‘Smoothee Golden Delicious’ apple to soil-applied triazole growth inhibitors. II: Mineral nutrition and carbohydrate status

Abstract

Emulsions containing 0 or 10 mg paclobutrazol, uniconazole or triapenthenol were applied to the soil of potted cultivar ‘Smoothee Golden Delicious’ apple ( Malus domestica, Borkh.) on M 9, M 7a or MM 111 rootstocks (M = Malling, MM = Malling-Merton). Significant differences in mineral concentrations occurred, depending on rootstock, tissue and plant growth regulator (PGR), but few consistent trends emerged. PGR had no effect on carbohydrates in plants on MM 111. The carbohydrate concentrations in plants on M 7a were most sensitive to PGR, although differences in relative carbohydrate concentrations were also evident in trees on M 9.