Greg Porter

Professor
School of Food and Agriculture
5722 Deering Hall, Room 114
Orono, Maine 04469

Degree:  Ph.D., Penn State, 1985

Research Topic:  Potato variety improvement; crop physiology; crop and soil management

Overview of Research: I have an interest in developing cropping systems which provide high yields and excellent crop quality, while having positive impacts on soil quality.  My research in this area includes long-term studies on the impacts of organic soil amendments (e.g. composts and manures) and crop rotations (e.g. type of rotations crops and length of rotations) on soils and crop productivity.  These studies have demonstrated the effectiveness of manures, composts, and longer rotation lengths at maintaining and/or improving soil physical properties; however, each management choice involves trade-offs and their benefits vary depending on the climatic conditions.  My research on potassium, nitrogen, phosphorus, and micro-nutrient fertility programs has provided information for growers to more efficiently management their potato crops, while maximizing yields and quality.  For example, new information from my program shows that potassium must be managed carefully to optimize the internal quality of potato tubers for fresh market and processing uses. I also am an active participant in local and regional potato variety improvement research.  Our goal is to select and commercialize new potato varieties with improved pest resistance and marketability for Eastern potato growers.

Representative Publications:
Sharifi, M., B.J. Zebarth, D.L. Burton, G.A. Porter, and C.A. Grant. 2008. Organic amendment history and crop rotation effects on soil nitrogen mineralization potential and soil nitrogen supply in a potato cropping system. Agronomy Journal 100:1562-1572.

Porter, G.A. et al. 2008. Eastern regional potato trials – 2007: Summary of NE1014 Regional Project Field Testing of New Potato Clones. Maine Agricultural and Forest Experiment Station Miscellaneous Publication 760.

Porter, G.A. et al. 2008. Eastern regional potato trials – 2006: Summary of NE1014 Regional Project Field Testing of New Potato Clones. Maine Agricultural and Forest Experiment Station Miscellaneous Publication 758.

Sharifi, M., B.J. Zebarth, D. L. Burton, C.A. Grant, G.A. Porter, J.M. Cooper, Y. Leclerc, G. Moreau, and W.J. Arsnenault. 2007. Evaluation of laboratory-based measures of soil mineral nitrogen and potentially mineralizable nitrogen as predictors of field-based indices of soil nitrogen supply in potato production. Plant Soil 301:203-214.

Mallory, E.B. and G.A. Porter. 2007. Potato yield stability under contrasting soil management strategies. Agronomy J 99: 501-510.

Olanya, O. M., D.H. Lambert, and G.A. Porter. 2006. Effects of pest and soil management systems on potato diseases. Amer J Potato Res 83:397-408.

Piper, A., M.S. Erich, G.A. Porter, and T.S. Griffin. 2006. Root growth effects on soluble C and P in manured and non-manured soils. Plant and Soil 283: 359-372.

De Jong, W.S., D.E. Halseth, B.B. Brodie, K.L. Perry, J.B. Sieczka, B.J. Christ, G.A. Porter, K.M. Paddock, M.W. Peck, and R.L. Plaisted. 2006. Marcy, a chipping variety with resistance to common scab and the golden nematode. Amer J Potato Res 83:189-193.

Porter, G.A. et al. 2006. Eastern regional potato trials – 2005: Summary of NE1014 Regional Project Field Testing of New Potato Clones. Maine Agricultural and Forest Experiment Station Miscellaneous Publication 757.

Porter, G.A. et al. 2006. Eastern regional potato trials – 2004: Summary of NE1014 Regional Project Field Testing of New Potato Clones. Maine Agricultural and Forest Experiment Station Miscellaneous Publication 756.

Porter, G.A. et al. 2006. Eastern regional potato trials – 2003: Summary of NE1014 Regional Project Field Testing of New Potato Clones. Maine Agricultural and Forest Experiment Station Miscellaneous Publication 755.

Ganga, Z.N., G.A. Porter, D. Lambert, G. Sewell, and A. Bushway. 2005. Reeves Kingpin: A high yielding processing variety suitable for fry processing. Amer J Potato Res 83:141-147

Stark, J.C. and G.A. Porter. 2005. Potato nutrient management in sustainable cropping systems. Amer J Potato Res 82:329-338.

Alyokhin, A. G. Porter, E. Groden, and F. Drummond. 2005. Colorado Potato Beetle response to soil amendments: A case in support of the mineral balance hypothesis? Agric Ecosys & Env 109:234-244.

Ohno, T., T.S. Griffin, M. Liebman, and G.A. Porter. 2005. Chemical characterization of soil phosphorus and organic matter in different cropping systems in Maine, U.S.A. Agriculture, Ecosystems, and Environment 105: 625-634.