Emeritus Professor, Plant Biology & Genetics
38 Academic Way
Durham, NH 03824
Office: (603) 862-1341
Seed Lab: (603) 862-4706
B.S., Oklahoma State University (Horticulture), 1963
M.S., Colorado State University (Genetics; Horticulture), 1965
Ph.D., Colorado State University (Genetics; Horticulture), 1967
Prior to accepting a half-time, fiscal year research appointment, I taught courses in Vegetable Crops, Plant Genetics and Reproduction, Crop Production Technologies and Plant Breeding. Past research interests were in hormonal regulation of cell and stem elongation, hormonal regulation of the cell cycle, crop physiology, and agricultural plastics. Currently, my primary research emphasis has been on variety development together with research on eating quality, nutrition, and the physiology of yield in cucurbits. Crop research within the Cucurbitaceae family includes Cucumis melon (melon), and breeding and allied research on the three major species of squash and pumpkin within the genus Cucurbita. In melon, the focus has been on developing early maturing cultivars of cantaloupes, Galia and some specialty melons. More recently, we have introduced a dominant gene for long shelf life into several melon backgrounds with a goal of attaining more consistently high sugar content and a longer harvest window, while also maintaining the flavor properties of a good melon.
A major emphasis in Cucurbita moschata (butternut and related types) and C. maxima (kabocha/buttercup types) has been determining carotenoid content and profiles in different cultigens, so as to identify cultigens with both a high content of carotenoids and those which have favorable profiles in terms of nutritionally beneficial carotenoids, lutein, zeaxanthin, α-carotene and β-carotene. Carotenoids and attributes which contribute to eating quality are being investigated in relation to squash maturity and storage. In Cucurbita pepo, within the acorn class of squash, the emphasis has been to increase the percent dry matter and rate of sugar development during squash maturation, so as to achieve better and more consistent eating quality.
Our melon program has been quite successful, thanks in a large part to excellent cooperative efforts with seed companies. UNH-developed ‘Earligold’ and ‘Earliqueen’ cantaloupe varieties were the standard in New England for several years. During the past few years these two varieties have been replaced with Earlichamp and Halona, respectively, which carry resistance to fusarium wilt and powdery mildew. In addition to these, UNH has released several other early to midseason varieties, many of which are adapted to a wider range of climates than the varieties mentioned above. These include ‘Goddess,’ ‘Maverick,’ ‘Strike,’ ‘Homerun,’ ‘Grandslam,’ ‘Rockstar,’ ‘Verona’ ‘Sarah’s Choice,’ ‘Wrangler,’ ‘Sugar Cube, ‘Solstice,’ and ‘Dutchess.’ Several specialty melons have been developed, many of which have been popular in the Northeast and in other regions of North America. Among these are the very early Galia varieties ‘Passport’ and ‘Diplomat,’ and the early midseason variety ‘Visa.’ Other specialty melons noted for their high sugar content and cream-colored flesh are ‘Sensation,’ ‘Dove,’ and ‘Gourmet.’
In ornamental pumpkin, the emphasis has been on developing suitable inbred lines for producing semi-bush hybrids adapted to close spacing and more amenable to weed control through cultivation. The breeding work is being done in collaboration with several seed companies, and often involves sharing of inbred lines in the hybrid varieties. The following hybrids utilizing UNH germplasm are being marketed successfully to growers by various seed companies: ‘Trickster,’ ‘Orange Smoothie,’ ‘Racer,’ ‘Big Rock,’ ‘Neon,’ ‘Hybrid Pam,’ ‘Pik-a-Pie,’ ‘Gold Standard,’ ‘Gold Medal,’ ‘Gold Challenger,’ ‘20-Karat Gold,’ ‘Hannibal,’ ‘Chucky,’ ‘Cidar Jack,’ ‘Champion’ and ‘Prankster.’ Two new white pumpkins ‘Moonshine,’ and ‘Snowball’, were recently introduced, and a yellow pumpkin hybrid will soon be commercially available.
In winter squash, breeding emphasis has been on developing varieties with a semi-bush habit of growth, more amenable to intensive culture and attaining uniform size and maturity. ‘Autumn Cup,’ a semi-bush, buttercup cultivar has now enjoyed success for several years. Three kabocha-type hybrids with exclusive UNH parentage, ‘Thunder’, ‘Eclipse’, and ‘Space Station’ are also being marketed. A powdery mildew tolerant (PMT), semi-bush, ‘Sweet Dumpling’-type hybrid, Sugar Dumpling, was first offered for sale in fall of 2008. A bush hybrid, PMR resistant variety of acorn, ‘Honey Bear,’ is noted for its superb eating quality and was an All-America Award Winner for 2009.
In summer squash, we discovered a glabrous gene which reduces the prickly spines (trichomes) on stems and petioles, reducing fruit damage and irritation to workers. The first introduction from this research, Slick Pik YS26, was introduced commercially available in 2009. Several more glabrous introductions are expected in the near future.
Breeding and genetic work with gourds has resulted in the release of the first egg (Goblin) and spoon (Koshare) gourds with the bush habit of growth and adapted to short growing seasons. This breeding work also laid the groundwork for important contributions to the genetics of pigment patterns in squash and pumpkin.
- Loy, J.B. 2000. Seed development in Cucurbita pepo: An overview with emphasis on hull-less seeded genotypes of pumpkin. Cucurbit Genet. Coop. Rpt. 23:89-95.
- Ouellette, A. and J.B. Loy. 2000. Effect of plant density and reflective polyethylene mulch treatments on growth and yield of tomato. Proc. Natl. Agr. Plastics Congr. 29:279-291.
- Cui, H. and J.B. Loy. 2002. Heterosis for seed yield exhibited in hull-less seeded pumpkin, p. 323-329. In: Maynard, D.N. (ed.). Cucurbitaceae 2002. ASHS Press, Alexandria, VA.
- Bezold, T.N., J.B. Loy, and S.C. Minocha. 2003. Changes in the cellular content of polyamines in different tissues of seed and fruit of a normal and a hull-less seed variety of pumpkin during development. Plant Science 164:743-752.
- Loy, J.B. 2004. Morpho-physiological aspects of productivity and quality in squash and pumpkins (Cucurbita spp.). Critical Rev. in Plant Sciences 23:337-363.
- Bezold, T.N., D. Mathews, J.B. Loy and S.C. Minocha. 2005. Molecular analysis of the hull-less seed trait in pumpkin: expression profiles of genes related to seed coat development. Seed Science Res. 15:205-217.
- Loy, J.B. 2006. Harvest period and storage affect biomass partitioning and attributes of eating quality in acorn squash (Cucurbita pepo). P. 568-577: in G.J. Holmes (ed.), Proceedings of Cucurbitaceae 2006. Universal Press, North Carolina.
- Loy, J.B. 2005-2006. Fruit size in melon in monoecious and adromonoecious isolines. Cucurbit Genetics Coop. Rpt. 28-29:12-13.
- Xiao, Q. and J. B. Loy. 2007. Inheritance and characterization of a glabrous trait in summer squash. J. Amer. Soc. Hort. Sci. 132:327-333.
- Noseworthy, J. and J.B. Loy. 2008. Improving eating quality and carotenoid content of squash, p. 52-528. In: M. Pitrat (ed.), Cucurbitaceae 2008: Proceedings of the IXth Eucarpia Meeting on Genetics and Breeding of Cucurbitaceae, INRA.
- Lelley, T., Loy, B. and M. Murkovic. 2010. Breeding Oil Seed Pumpkins. In: Handbook on Plant Breeding, V. 4:469-492, Oil Crops, J. Vollman and I Rajcan (eds.), Springer, New York.
- Uretsky, J. and J.B. Loy. 2010. Vegetative growth in bush Cucurbita maxima x vine Cucurbita moschata interspecies hybrids, p. 105-108. In: J.A. Thies, S. Kousik and A. Levi (eds.), Proceedings Cucurbitaceae 2010, ASHS Press, Alexandria, VA.
- Loy, J.B. 2012. Breeding Squash and Pumpkins, pp. 93-139. In: Y-H Wang, T.K Behera and C. Kole (eds.), Genetics, Genomics and Breeding of Cucurbits. CRC Press. New York, NY.
- Loy, J.B. 2012. Introgression of genes conferring the bush habit of growth and variation in fruit rind color into white nest egg gourd, pp. 275-282. In: N. Sari, I. Solmaz, and V. Aras (eds.), Cucurbitaceae 2012 Proceedings, Adana, Turkey, Ҫukurova University.