successfully rooted a low percentage of pawpaw softwood cuttings. Micropropagation techniques have been developed for many Annonaceous relatives of pawpaw, indicating promise of this technology for pawpaw (Bejoy and Hariharan, 1992; Jordan, 1988; Jordan et al., 1991; Nair et al., 1983, 1984a, 1984b, 1986; Rasai et al., 1994). In attempting to micropropagate pawpaw, we have found that dormant, winter-harvested twigs that are surface-sterilized and then forced (in water) in a growth chamber provide the best source of explants (i.e., nodal cuttings) from the newly developing shoots. We currently have adventitious shoots proliferating in culture and will soon move them to a rooting medium. Embryo culture is a technique that might be used to rescue interspecific or intergeneric hybrids that would otherwise abort due to incompatibility (Pierik, 1989).

No chemicals are currently registered for commercial use on pawpaws. We use N-(phosphonomethyl)glycine (glyphosate; RoundUp) and 1,1′-dimethyl-4,4′-bipyridinium salts (paraquat) for maintaining a weed-free, herbicide strip down orchard rows in our research plots. We have had only minor infestations in the field of Japanese beetle (Popillia japonica Newman), and 1-naphthalenyl methylcarbamate (carbaryl; Sevin) is effective in treating this pest. Greenhouse pests include aphids (Family: Aphididae) and thrips (Family: Thripidae). Sevin is also effective for these pests in the greenhouse.

The economic rationale for the development of pawpaw as a new fruit crop is very much tied to the need, in certain areas of the country, to find new high-value crops to replace old ones that are losing value. Tobacco (Nicotiana tabacum L.) is one example. Since 1976, the percentage of total world tobacco produced by the United States has dropped from 53% to 28% (Owens, 1994b). Significant opportunities exist for the development of alternative agricultural enterprises that could help tobacco farmers to diversify and thereby enhance their continued, long-term viability.

In Kentucky, tobacco is grown on small acreages in rural areas and tobacco sales contribute significantly to the small-farm family income. At KSU the central mission of the land-grant program is to address the needs of limited-resource (small) farmers, most of whom will be harmed by declines in tobacco production and revenue generation (Gale, 1994). One current, long-term and ongoing initiative at KSU to address the aforementioned need is the development of pawpaw as a new, commercial, tree fruit crop. Pawpaw is well adapted to all 16 tobacco-growing states in the United States, except Florida. Pawpaw cultivation in these tobacco-producing states can add diversity and has the potential to provide significant income for a portion of these states' farmers over 20 to 30 years.

Pawpaw has tremendous potential as a new fruit crop because of its 1) adaptation to existing climatic and edaphic conditions; 2) nutritional and cosmetic value of the fruit; 3) valuable natural compounds; 4) nursery wholesale and retail tree production; and 5) use as a component in residential “edible” landscapes. Pawpaw is well adapted to the 25 states to which it is native and where it already grows in the wild. It is hardy to zone 5 (-25°C) and requires a minimum of 400 h annual chill units, 160 frost-free days, and 80 cm of annual precipitation, with most falling during spring and summer (Peterson, 1991). Pawpaw trees may be used for habitat restoration and biodiversification in parks, wood lots, and forests. Pawpaw is an excellent food source. It exceeds apple (Malus domestica Borkh.), peach [Prunus persica (L.) Batsch.], and grape (Vitis spp.) in most vitamins, minerals, amino acids, and food energy value (Peterson et al., 1982). Pawpaw fruit are best eaten fresh when fully ripe. The intense tropical flavor and aroma (Shiota, 1991) also may be useful for developing processed food products (blended fruit drinks, baby food, ice creams, etc.). The flesh purees easily and freezes nicely. Pawpaws easily substitute in equal part for banana in most recipes (Jones and Layne, 1996). Aromas may be used commercially in cosmetics and skin products (B. Hecking, perfume chemist, Mane, USA Division, Wayne, N.Y., personal communication). Pawpaw plants produce natural compounds (annonaceous acetogenins) in leaf, bark, and twig tissues that possess both highly antitumor and pesticidal properties (McLaughlin and Hui, 1993; Mikolajczak et al., 1988; Rupprecht et al., 1986; Zhao et al., 1994). Current research by Jerry McLaughlin at Purdue Univ. (personal communication) suggests that a potentially lucrative industry, based simply on production of plant biomass, could develop for production of anticancer drugs [pending Food and Drug Administration approval] and natural (botanical) pesticides. The high level of natural defense compounds in the tree make it highly resistant to insect/disease infestation (R.N. Peterson, personal observation). With proper management, organic commercial fruit production may be possible. Currently in the United States, there are more than 40 commercial nurseries selling pawpaw trees. Seedling and grafted trees in the retail nursery trade are currently selling briskly for as much as $18.50 and $26.50 a piece, respectively, vs. $3.00 to $4.00 for a 2-year-old, grafted apple tree. Currently, standing orders are in excess of 40,000 trees in the wholesale market (Jim Gilbert, personal communication). Pawpaws are ideally suited for the residential “edible” landscape due to their lush, tropical appearance; attractive growth form; size; fall color; and delicious fruit. In addition, Asimina spp. are suitable for butterfly gardens, as they attract the zebra swallowtail (Eurytides marcellus Cramer), for whom they are the exclusive larval host plant (Damman, 1986).

food, ice creams, etc.). The flesh purees easily and freezes nicely. Pawpaws easily substitute in equal part for banana in most recipes (Jones and Layne, 1996). Aromas may be used commercially in cosmetics and skin products (B. Hecking, perfume chemist, Mane, USA Division, Wayne, N.Y., personal communication). Pawpaw plants produce natural compounds (annonaceous acetogenins) in leaf, bark, and twig tissues that possess both highly antitumor and pesticidal properties (McLaughlin and Hui, 1993; Mikolajczak et al., 1988; Rupprecht et al., 1986; Zhao et al., 1994). Current research by Jerry McLaughlin at Purdue Univ. (personal communication) suggests that a potentially lucrative industry, based simply on production of plant biomass, could develop for production of anticancer drugs [pending Food and Drug Administration approval] and natural (botanical) pesticides. The high level of natural defense compounds in the tree make it highly resistant to insect/disease infestation (R.N. Peterson, personal observation). With proper management, organic commercial fruit production may be possible. Currently in the United States, there are more than 40 commercial nurseries selling pawpaw trees. Seedling and grafted trees in the retail nursery trade are currently selling briskly for as much as $18.50 and $26.50 a piece, respectively, vs. $3.00 to $4.00 for a 2-year-old, grafted apple tree. Currently, standing orders are in excess of 40,000 trees in the wholesale market (Jim Gilbert, personal communication). Pawpaws are ideally suited for the residential “edible” landscape due to their lush, tropical appearance; attractive growth form; size; fall color; and delicious fruit. In addition, Asimina spp. are suitable for butterfly gardens, as they attract the zebra swallowtail (Eurytides marcellus Cramer), for whom they are the exclusive larval host plant (Damman, 1986).

Pawpaws have a well-established place in folklore and American history. “Where, oh where, is dear little Nellie (Sallie, etc.)? ‘Way down, yonder in the pawpaw patch.’” This traditional American folk song and game was quite popular once and hunting for pawpaws in the woods in the fall is a cherished tradition for many rural families in the southeastern United States. In reference to the pawpaw, John Lawson said in his 1709 book, A New Voyage to Carolina, that they are “as sweet, as any thing can well be. They make rare Puddings of this Fruit.” John Filson, an early settler, promoter, and developer of Kentucky, said in his 1784 book, The Discovery, Settlement and Present State of Kentucky, “the pappa-tree does not grow to a great size, is a soft wood, bears a fine fruit much like a cucumber in shape and size, and tastes sweet.” Daniel Boone and Mark Twain were reported to have been pawpaw fans. In their journal entry on 18 Sept. 1806, Lewis and Clark recorded how pawpaws helped save them from starvation, “our party entirely out of provisions subsisting on poppaws. We divided the buiskit which amounted to nearly one buiskit per man, this in addition to the poppaws is to last us down to the Settlement’s which is 150 miles. The party appear perfectly contented and tell us that they can live very well on poppaws”. John James Audubon painted the yellow-billed cuckoo on a native paw-paw tree (ca. 1827). During the famous Hatfield–McCoy feud along the Kentucky–West Virginia border, on 9 Aug. 1882, three sons of Randolph McCoy (clan leader) were tied to pawpaw bushes and executed by the rival Hatfield family (Owens, 1994a). Several American towns, townships, creeks, and rivers were named after the pawpaw during the 19th century.

Several national organizations have had a long-standing interest in pawpaws, including the Northern Nut Growers Association, the North American Fruit Explorers, and the California Rare Fruit Growers, Inc. In 1988, R. Neal Peterson founded The PawPaw Foundation (PPF) as a nonprofit organization “dedicated to research and development of Asimina triloba as a new fruit crop for American farmers and consumers.” Currently, PPF has almost 300 members. PPF, under the leadership of Peterson, has been active in collecting, evaluating, and preserving germplasm; breeding pawpaws; distributing fruit; selling seed; interacting with research scientists; and educating the public. PPF receives hundreds of letters each year requesting information about pawpaws. PPF also publishes a semi-annual newsletter, “From The