2017 ASHS Annual Conference

Pawpaw (Asimina triloba), a tree fruit native to the Eastern U.S., is in small-scale commercial production with its popularity on the rise. Many small farmers have seedling pawpaw trees or wild trees that produce low yields and poor quality fruit. New commercially available pawpaw varieties are available that will increase yield, fruit quality, and improve consumer opinion and demand of fruit. Bark inlay is a grafting technique which allows the union of a rootstock limb or trunk that is much larger in size than the scion. This technique has not been well developed for pawpaw and is a potential method for growers to change over wild and/or seedling pawpaw trees to higher yielding, higher quality cultivars. The objective of this study was to determine the optimum timing for bark inlay grafting in pawpaw. Three commercially available pawpaw cultivars with large, high quality fruit and high yields were selected: ‘KSU-Atwood’, ‘Sunflower’, and ‘Susquehanna’. Three trees of each cultivar were grafted on two dates, early vs. late May, at two locations, the Kentucky State University H.R. Benson Research and Demonstration Farm, and a local commercial grower’s site. Trees grafted using the bark inlay method in early May (May 3) had a success rate of 91%, whereas trees grafted in late May (May 23) had a success rate of 67%. Growth was similar between the two dates, with scions grafted in early May growing an average of 0.78 m, while scions grafted in late May grew an average of 0.76 m. Due to a higher success rate, early May is preferable to late May for performing bark inlay grafting of pawpaw trees.