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tivars and advanced selections were correlated between the two plantings. Tree survival was likely greater at the Frankfort planting than at the Princeton planting due to trees being irrigated at the Frankfort planting but not at Princeton. Additionally, trees were fall planted at the Princeton site and spring planted at the Frankfort site; pawpaws often have a lower establishment rate with fall planting. During the 7th, 8th, and 9th years after planting, trees in the Frankfort trial displayed greater vigor than those in the Princeton trial. The greater vigor at Frankfort was likely due to supplemental irrigation there. More vigorous clones had larger cumulative yield per tree, but not a greater number of fruit per tree. Most clones had average fruit weights over 100 g which would be desirable for growers and consumers. Most cultivars and advanced selections averaged about two fruit per cluster, which is also desirable. Single fruit clusters are most desirable, since harvesting the fruit by cutting the peduncle would not leave the open scar that accompanies pulling fruit from a cluster. Cumulative yield efficiency for the pawpaw clones examined was lower than reported for many apple cultivars (2), with no pawpaw clones having cumulative yield efficiency greater than 1.0. ‘PA-Golden’ and 2-10 required around 2500 GDDs for fruit to ripen and would be desirable for production in northern climates. No pawpaw clones displayed concentrated ripening periods. Biennial bearing was observed with some clones in the Frankfort planting, likely the result of a devastating frost event in 2003, because biennial bearing was not observed in any of these same selections at Princeton.

Pawpaw yields are lower than would be expected for most other tree fruits (17). Bartholomew (1) reported obtaining 4 kg of fruit and Ourecky and Slate (13) obtained 11.5 and 23 kg/year from superior pawpaw trees. Selections in this study did not exceed yields for superior pawpaw trees previously reported (13). Although PPF advanced selections failed to show greater yields than previously available cultivars in this study, some PPF selections may have higher quality fruit. Duffrin and Pomper (3) developed a descriptive language for frozen pawpaw fruit puree where panelists generated 13 visual, 17 flavor, and 12 texture puree descriptors. Using these descriptors with fruit collected from non-cultivated native sites in southeast Ohio and two PPF advanced selections, collected from the Frankfort trial (1-23 and 10-35), panelists identified positive characteristics of stronger melon and fresh flavors compared to puree from native Ohio fruit. These advanced selections both performed well in terms of fruit size and yield in the Princeton and Frankfort trials. Fruit quality of all PRVT cultivars and advanced selections will be examined in future studies.

may have higher quality fruit. Duffrin and Pomper (3) developed a descriptive language for frozen pawpaw fruit puree where panelists generated 13 visual, 17 flavor, and 12 texture puree descriptors. Using these descriptors with fruit collected from non-cultivated native sites in southeast Ohio and two PPF advanced selections, collected from the Frankfort trial (1-23 and 10-35), panelists identified positive characteristics of stronger melon and fresh flavors compared to puree from native Ohio fruit. These advanced selections both performed well in terms of fruit size and yield in the Princeton and Frankfort trials. Fruit quality of all PRVT cultivars and advanced selections will be examined in future studies.

Cherimoya (Annona cherimola), sweetsop or sugar apple (A. squamosa), soursop (A. muricata), and atemoya (A. squamosa × A. cherimola), are tropical relatives of the pawpaw and also have low yields due to low rates of natural pollination (5, 15, 17). In commercial plantings, these tropical pawpaw relatives are hand-pollinated to increase yields (15, 17). Low rates (<5%) of fruit set have also been noted in wild pawpaw patches (9, 23). Native pawpaw patches common in the forest understory are often root suckers of a single clone that will not self-pollinate. In addition, sunlight levels are very low in the shaded understory. Further, pollinators may be limited in this setting (23). At the KSU site, pawpaw genotypes are in close proximity to goat herds at the same farm about 150 m from the pawpaw orchards. Flies are abundant, therefore, pollinator limitation and opportunities for cross-pollination are not likely limiting in the KSU orchards. It has been suggested by some hobbyists that ‘Sunflower’ may be self-fruitful, but this has not been experimentally documented. ‘Sunflower’ did not produce the greatest number of fruit per tree in this study, suggesting that if it is self-fruitful, pollinator limitation was not a factor. Pollinizer relationships between pawpaw cultivars and advanced selections have not been examined and could be valuable for growers who may not plant a diverse group of pawpaw cultivars.