A. R. Biggs, Associate Professor, West Virginia University, University Experiment Farm, P.O. Box 609, Kearneysville, WV, USA, 25430

 ABSTRACT

Biggs, A. R. 1991. Leaf abscission kinetics of peach cultivars and clones in relation to peach canker disease. Can. J. Bot. 69:2020-2025.

Leaf abscission kinetics of several peach cultivars and clones were studied for 2 or 3 years at two locations. Cultivars varied significantly in leaf abscission rates, dates of 50 and 75% leaf abscission, and area under the abscission progress curve (AUAPC). The cultivars Veeglo, Madison, and Vivid exhibited the most rapid rates of leaf abscission, clone V68101 and Redhaven showed moderate rates of leaf abscission, and Babygold 5, Vanity, Candor, Earlired, and clone V68051 were relatively slow to abscise leaves. No significant relationship could be demonstrated for any of the leaf abscission parameters with field performance ranks of cultivar susceptibility to the peach canker pathogens. Mean annual harvest date for the various cultivars or clones was not associated with susceptibility to the peach canker pathogens or any of the leaf abscission parameters. The role of autumn wound response in relation to screening for pathogen resistant peach genotypes is discussed.