The Kentucky Pawpaw Regional Variety Trial

Abstract

The North American pawpaw [ Asimina triloba(L.) Dunal] is in the initial stages of commercial production. Two pawpaw variety trial orchards were established in Kentucky to evaluate the suitability of various varieties for this region. The first orchard was planted in the fall of 1995 in Princeton, at the University of Kentucky Research and Education Center (UKREC). A second orchard was planted in the spring of 1998 at the Kentucky State University (KSU) Research Farm in Frankfort. A randomized complete block design was used in both plantings with 8 replicates of 28 grafted cultivars and advanced selections. Cultivars being evaluated included ‘Middletown’, ‘Mitchell’, ‘NC-1’, ‘Overleese’, ‘PA-Golden’, ‘Sunflower’, ‘Taylor’, ‘Taytwo’, ‘Wells’, and ‘Wilson’. The other 18 clones were selections from the PawPaw Foundation (PPF) breeding effort. Trunk cross-sectional area, number of fruit per tree, fruit weight, cumulative yield, cumulative yield efficiency, number of fruit per cluster, growing degree days required for ripening, harvest peak, harvest duration (days), and biennial bearing index all varied significantly among cultivars and advanced selections 7 to 9 years after planting at both planting sites. Fruit weight varied greatly, with some clones averaging less than 100 g per fruit (‘Middletown’, ‘Wilson’, and ‘Rappahannock’) and others averaging over 170 g per fruit (‘Overleese’, 8-20, ‘NC-1’, ‘Susquehanna’, ‘Wabash’, 5-5, and ‘Potomac’). ‘PA-Golden’ and 2-10 were early ripening clones while ‘Middletown’ and 9-47 were late ripening clones. Cumulative yield varied greatly, with some cultivars and advanced selections exceeding 30 kg/tree. Cumulative yield efficiency ranged from 0.38 to 0.91 kg/cm 2TCA. Based on fruit size yield, and availability, ‘Potomac’, ‘Susquehanna’, ‘Wabash’, ‘Overleese’, ‘Shenandoah’, ‘NC-1’, and ‘Sunflower’ can be recommended for production in this region. Additional PPF advanced selections that show promise are 10-35, 9-58, 2-10, 8-20, 5-5, and 1-68.