The response of flowering date and cropping ofPyrus communiscv. Concorde to autumn warming

Abstract

SummaryThe effect of autumn temperature on the flowering date and cropping of Pyrus communis cv. Concorde was examined. Trees were given artificially warm nights, designed to mimic autumn daily mean maximum temperatures by enclosing them in mobile greenhouses at night in October and November. Warming potted trees in both months delayed the time at which flower buds began to swell and subsequently influenced the developmental sequence of flowering. Treatment differences in the phenological development of the flower clusters became less obvious by full bloom. There was no evidence to suggest that flower bud number per tree or flower number per cluster changed in response to warming. Warmed trees showed less low-temperature injury due to late spring frost than the unwarmed control trees. Despite this, the initial and final fruit sets were very similar. The results of this work are discussed in relation to year-to-year variations in the cropping of pear and are compared with earlier experiments with pear cv. ...