Scionwood of Apple Cultivars, Rootstocks and Species Available from the Plant Introduction Station

Abstract

The U. S. Department of Agriculture maintains a large collection of apple germplasm at its Plant Introduction Station, Glenn Dale, Maryland. The items are clonal introductions assembled from countries during the past 50 years. Nearly all are included and partially described in "Fruit and Tree Nut Germplasm Resources Inventory" by Fogle and Winters (2). Their origin and the purpose for bringing them into the U.S.A., along with some of their unusual virtues are given in the Published Inventory Series which is available in most State College of Agriculture Libraries (4). The introductions represent a diverse collection of exotic varieties, breeding lines, wild types, root stocks and species. Some of the older introductions have endured prolonged adverse environmental conditions and exposure to several diseases. Fireblight, scab, and leaf-spot (caused by Fabraea maculata) are among the diseases seen in our orchards. Ackerman and Winters (1) described varieties in the collection that originated in warm climates and hence have low chilling requirements.