Inhibitor of Receptacle Growth in Non-pollinated Strawberry Fruit

Abstract

THE strawberry fruit grows after flowering only if the carpels are fertilized or if the fruit is treated with growth substances^1–3. Fertilization of a limited number of carpels gives rise to irregularly shaped receptacles, which are swollen only near the achenes. Unfertilized fruit of a number of varieties (for example, ‘Freya’), however, sometimes swells at the base of the receptacle, which lacks carpels. Furthermore, when carpel development is suppressed by spraying the plant with maleic hydrazide at an early stage of flower development, the receptacle grows. It has therefore been suggested that the lack of growth near unpollinated carpels may be the result of the production, by the carpels, of an inhibitor⁴.