John R. Clark
John R. Clark
Phone: (479) 575-2810
Fax: (479) 575-8619
Department of Horticulture
316 Plant Sciences Building
University of Arkansas
Fayetteville, AR 72701
· Ph.D. University of Arkansas, Fayetteville, AR
· M.S. Mississippi State University, Starkville, MS
· B.S. Mississippi State University, Starkville, MS
HORT5043: Advanced Plant Breeding
HORT4103: Fruit Production Science and Technology
Fruit breeding is conducted on blackberries, grapes, and peaches/nectarines. Classical breeding for cultivar development is the major emphasis. Supporting studies on breeding methodology and related areas are also underway including marker-assisted techniques and applications.
The fruit breeding program has developed a number of cultivars. To view variety information and a list of licensed propagators, please visit Arkansas Agriculture - Commercial Horticulture, sponsored by the Arkansas Cooperative Extension Service.
General Areas of Interest:
Development of fruit cultivars is the major area of focus, using classical breeding approaches. Cultivars are developed that are targeted for adaptation in Arkansas and other areas with similar climate. Innovations in cultivar improvement include improved postharvest quality, flavor enhancement, plant architecture, and season of ripening extension. The largest breeding effort is in blackberries, where innovations include the introduction of the world's first primocane-fruiting cultivars allowing broader season of ripening and plant management options. Applied molecular methods are utilized for seedling and parent selection. Inclusion of undergraduate and graduate students in research is also a focus area.
Fruit Breeding's Future by Matt Milkovich in Fruit Grower News - October 2015
Cotton Candy Story by John Clark in Fruit Grower News - October 2015
Recent Selected Publications
Clark, J.R. and D. W. Barchenger. 2015. Breeding muscadine grapes in Arkansas: A new initiative. Acta Hort. 1082:95-98.
Barchenger, D.W., J.R. Clark, R.T. Threlfall, L.R. Howard, and C.R. Brownmiller. 2014. Effect of field fungicide applications on storability, physicochemical, and nutraceutical content of muscadine grape (Vitis rotundifolia Michx.) genotypes. HortScience 49:1315-1323.
Barchenger, D.W., J.R. Clark, R.T. Threlfall, L.R. Howard, and C.R. Brownmiller. 2015. Evaluation of physiochemical and storability attributes of muscadine grapes (Vitis rotundifolia Michx.). HortScience 50:104-111.
Barchenger, D.W., J.R. Clark, R.T. Threlfall, L.R. Howard, and C.R. Brownmiller. 2015. Nutraceutical changes in muscadine grape and grape segments during storage. J. Amer. Pomol. Soc. 69:66-73.
Clark. J.R. 2014. Prime-Ark® Freedom primocane-fruiting thornless blackberry. HortScience 49:1097–1101.
Clark, J.R., K. Demchak, C.E. Finn, J.D. Lowe, K.W. Pomper, and S.B. Crabtree. 2014. 'Black Magic' ™ primocane-fruiting blackberry. J. Amer. Pomological Society 68: 163-170.
Jaureguy, L.M., P. Chen, K. Brye, D. Oosterhuis, A. Mauromoustakos, and J.R. Clark. 2014. Potential association between soil and leaf chemical properties and soybean seed composition. Agric. Sci. 5: 560-570.
Lowe, J.D., K.W. Pomper, S.B. Crabtree, J.R. Clark, and J.G. Strang. 2014. Primocane yield of Prime Ark® 45 and Prime-Jan blackberries growing using USDA National Organic Program practices in Kentucky. J. Amer. Pomol. Soc. 68:221-226.
Yue, C., R.K. Gallardo, J.J. Luby, A.L. Rihn, J.R. McFerson, V. McCracken, T. Gradziel, K. Gasic, G.L. Reighard, J. Clark, and A. Iezzoni. 2014. An evaluation of U.S. peach producers' trait prioritization—evidence from audience surveys. HortScience 49: 1309-1314.