Martin P.N. Gent


Plant Physiology, Nutrition, Gas Exchange, Carbohydrate and Nitrogen Metabolism. Environment response of plants. Greenhouse vegetable production, Hydroponics, Mathematical modeling.


BA, with Honors in Chemistry, Oberlin College 1971

PhD, Physical Chemistry, Yale University 1975

Station Career:

Assistant Scientist 1978-1989

Associate Scientist 1989-2003

Agricultural Scientist 2004-2009

Emeritus Scientist 2009-current

Current research areas:

Dr. Gent applies plant physiology to horticultural crops such as tomato and salad greens to relate growth, yield, and tissue composition to environment and metabolism.  Currently, he is modelling uptake and growth of hydroponic lettuce and spinach in response to sunlight and nitrogen concentrations. A model of lettuce is available here. You will need Vensim Reader to run the model:

Past research:

The effect of partial saturation ebb&flow watering on growth and spread of disease in potted ornamentals grown in greenhouses. Carbohydrate and nitrogen metabolism, nutrient uptake, and rate of production in greenhouse tomato, lettuce, and spinach plants, as related to light, carbon dioxide, and air and root zone temperature. Leaf and canopy photosynthesis of eggplant and potato affected by Verticillium wilt and other pests. Differences among wheat varieties in canopy photosynthesis and metabolism of sugars. The effects of growth regulator chemicals on growth and flowering of Rhododendron and Mountain Laurel.

Selected publications available from the author,


  • Gent, M.P.N. 2018. Dynamic Carbohydrate Supply and Demand Model of Vegetative Growth: Response to Temperature, Light, Carbon Dioxide, and Day Length. Agronomy 8: 21; doi: 10.3390/agronomy8020021
  • Gent, M.P.N., W.H. Elmer. 2017. Partial saturation ebb and flow irrigation and silicon to suppress Pythium root rot of poinsettia. Crop Protection 101:95-102.
  • Gent, M.P.N., W.H. Elmer, K. Macherla and R.J. McAvoy. 2016. Effects of Salinity and Irrigation Management on Poinsettia. HortScience 51:427ā€“434.
  • Gent, M.P.N. 2016. Effect of irradiance and temperature on composition of spinach. HortScience 51:133-140.
  • Seginer I, Gent, M.P.N. 2014. Short and long term vegetative growth response to temperature, interpreted by the dynamics of a carbohydrate storage. Scientia Horticulturae 171:14-26.
  • Gent, M.P.N. 2014. Effect of Daily Light Integral on Composition of Hydroponic Lettuce. HortScience 49:173-179.
  • Gent, M.P.N and I. Seginer. 2012. A Carbohydrate Supply and Demand Model of Vegetative Growth: Response to Temperature and Light. Plant Cell Environment 35:1274-1286.
  • Gent, M.P.N. 2012. Composition of hydroponic lettuce: Effect of time of day, plant size, and season. J. Sci. Food. Agric. 92:542-550.
  • Gent, M.P.N and R.J. McAvoy. 2011. Water and Nutrient Uptake and Use Efficiency with Partial Saturation Ebb and Flow Watering. HortScience 46:791-798.
  • Gent, M.P.N. 2008. Density and Duration of Shade Affect Water and Nutrient Use in Greenhouse Tomato. J. Amer. Soc. Hort. Sci. 133:619-627.
  • Gent, M.P.N. 2007. Effect of Degree and Duration of Shade on Quality of Greenhouse Tomato. HortScience 42:514-520.
  • Gent, M.P.N., J.C. White, B.D. Eitzer, M.J.I. Mattina. 2007. Modeling the Difference among Cucurbita in Uptake and Translocation of p,p'-dichlorophenyl-1,1-dichloroethylene. Environ. Toxicol. Chem. 26:2476-2485.
  • Gent, M.P.N., J.C. White, Z.D. Parrish, M. Iseleyen, B.D. Eitzer, M.J.I. Mattina. 2007. Uptake and Translocation of p,pā€™-dichlorodiphenyldichloroethylene supplied in Hydroponics Solution to Cucurbita. Environ. Toxicol. Chem. 26:2467-2475.
  • Gent, M.P.N. 2004. Efficacy and persistence of paclobutrazol applied to rooted cuttings of rhododendron before transplant. HortScience 39:105-109.
  • Gent, M.P.N. 2003. Effect of conductivity and nitrate supply ratio on nitrate accumulation in hydroponic lettuce. HortScience 38:222-227.
  • Gent, M.P.N., Y-Z Ma. 2000. Growth and mineral nutrition of tomato seedlings under diurnal temperature variation of the root and shoot. Crop Science 40:1629-1636.
  • Gent, M.P.N., J.A. LaMondia, F.J. Ferrandino, W.H. Elmer, K.A. Stoner. 1999. The influence of compost amendment or straw mulch on the reduction of gas exchange in potato by Verticillium dahliae and Pratylendchus penetrans. Plant Disease 83:371-376.
  • Gent, M.P.N., Y-Z Ma. 1998. Diurnal temperature variation of the root and shoot affects yield of greenhouse tomato. HortScience 33:47-51.
  • Gent, M.P.N., R.K. Kiyomoto. 1998.  Physiological and agronomic consequences of Rht genes in wheat.  J. Crop Production 1:27-46
  • Gent, M.P.N. 1994.  Photosynthate reserves during grain filling in winter wheat.  Agronomy Journal 86:159-167.