A detailed history describing the development of these varieties and the relationship between the different lines of germplasm that have gone into their pedigree has not been recounted in a single narrative before. This paper traces the development of pawpaw varieties from the earliest record in 1905 and applies the lessons learned from that history to the prospects for future pawpaw breeding.
evaluation of wild selections leading to advanced selections; 3) production of controlled crosses between selections;
evaluation of advanced selections and hybrids; 5) preservation and character- ization of germplasm; 6) horticultural and genetic research of the new crop; 7) testing and release of proven varieties;
development of commercial orchards and markets; and 9) scientifi c breeding based on defi ned objectives. To date the pawpaw is in the middle stages of domestication. Superior wild selections have been identifi ed and propagated, small scale evaluations have been made, regional variety trials for the systematic evalu- ation of advanced selections initiated, controlled crosses and hybrids created, a germplasm repository established, and numerous scientifi c studies of the spe- cies conducted. However, to date no proven varieties have been released to the public, no commercial orchards are in bearing, and no scientifi c breeding program based on hand-pollinated seedlings from controlled crosses with well-defi ned objectives using statisti- cal methods and sound experimental design exists. 1900 TO1950: SELECTIONS FROM THE WILD, A NATIONAL CONTEST, AND BREEDING. The earliest record of pawpaw variety development is found in Little’s trea-
To date the pawpaw is in the middle stages of domestication. Superior wild selections have been identified and propagated, small scale evaluations have been made, regional variety trials for the systematic evaluation of advanced selections initiated, controlled crosses and hybrids created, a germplasm repository established, and numerous scientific studies of the species conducted. However, to date no proven varieties have been released to the public, no commercial orchards are in bearing, and no scientific breeding program based on hand-pollinated seedlings from controlled crosses with well-defined objectives using statistical methods and sound experimental design exists.
1900 to 1950: SELECTIONS FROM THE WILD, A NATIONAL CONTEST, AND BREEDING. The earliest record of pawpaw variety development is found in Little's trea
Fig. 1. Pawpaw cultivar development and major lines of descent, 1900 to 1950.
tise (1905). This small book contains many excellent observations that are still relevant today. Little states that he selected the first named pawpaw, ‘Uncle Tom’ (Fig. 1). This variety was the result of planting open-pollinated seed from superior fruit that he collected in the wild over many years. The year of selection and naming was not listed. He also discusses having planted in 1895 a “regularly laid out orchard” from select seed, consisting of 35 trees, on the property of Judge John V. Hadley—later transferred to Jasper Thompson, (Popenoe, 1917)—in Danville, Ind.
A second important pawpaw grower of that period was Benjamin Buckman of Farmingdale, Ill. (Fig. 1). Buckman was a horticulturist with wide ranging interests in fruit and nut trees, was the originator of the ‘Farmingdale’ pear rootstock, and possessed a collection containing 1743 varieties of 20 different species (unpublished record of Buckman’s plantings, received from D. Robson). Buckman corresponded widely with fruit growers and enthusiasts living in Illinois, Arkansas, Indiana, West Virginia, and Ohio. He assembled a collection of twelve named pawpaw varieties (Popenoe, 1917).
The greatest single impulse toward the development of pawpaw varieties was the contest of 1916 sponsored by the American Genetics Association (Popenoe, 1916, 1917) (Fig. 1). This contest resulted in the submission of fruit from 75 trees, uncovered most of the known pawpaw varieties of the time, and stimulated great interest among amateur and professional horticulturists. The prize was awarded to Mrs. Ketter of Ironton, Ohio, while six other entries were judged superior to the rest and deemed worthy of propagation. David Fairchild, eminent horticulturist and one of the initiators of the contest, grafted ‘Ketter’ at his property in Chevy Chase, Md., and grew seedlings from the prize winning fruit (letter, P. Popenoe 7 Apr. 1923, in the files of J. Popenoe and the author). He subsequently selected one seedling of ‘Ketter’ as superior, even to its parent, which he named ‘Fairchild’ (Zimmerman, 1941).
est among amateur and professional horticulturists. The prize was awarded to Mrs. Ketter of Ironton, Ohio, while six other entries were judged superior to the rest and deemed worthy of propagation. David Fairchild, eminent horticulturist and one of the initiators of the contest, grafted ‘Ketter’ at his property in Chevy Chase, Md., and grew seedlings from the prize winning fruit (letter, P. Popenoe 7 Apr. 1923, in the files of J. Popenoe and the author). He subsequently selected one seedling of ‘Ketter’ as superior, even to its parent, which he named ‘Fairchild’ (Zimmerman, 1941).
With strong encouragement from David Fairchild, George A. Zimmerman undertook an 18-year project of ambitious pawpaw breeding (Zimmerman, 1938, 1941) (Fig. 1). In 1923 Zimmerman began a collection of pawpaw varieties at his home near Piketown, Pa., (letters, Popenoe 7 Apr. 1923, and Zimmerman 31 Mar. 1923, in the files of J. Popenoe and the author). In time he assembled an extensive collection of pawpaw varieties, numbering over 60 named varieties and unnamed seedlings, and probably included all known varieties of his time. He stated that some of his finest varieties came from Buckman's collection. Some trees in his collection were controlled crosses between the better varieties but these were neither named nor released. He unsuccessfully attempted to produce intergeneric hybrids by crossing Annona squamosa and atemoya (A. squamosa × A. reticulata) with Asimina triloba.