Background

Jeff’s has a background in plant science and viticulture lecturing and research spanning over 10 years. Areas of past work have included herbage seed physiology, ornamental bulb physiology and more recently viticulture and grapevine physiology. Before joining HortResearch he was a research officer with the Marlborough Wine Research centre and previous to that a viticulture lecturer and researcher for Lincoln University at both Lincoln University (Canterbury) and Nelson Marlborough Institute of Technology (Marlborough) campuses.  Jeff completed his research PhD at Lincoln University in March 2002.  His research focussed on the impacts of management practices on carbohydrate reserve physiology of mature grapevines in cool climate viticulture areas.   Jeff's research provided new insight into understanding the relationship between overwintering carbohydrate reserves and return bloom and cropping performance.

Expertise

Field based viticulture:  Grapevine propagation, and establishment.  Grapevine training, crop manipulation and pruning.  Pest and disease assessment and control. Grapevine-soil nutrition and irrigation diagnosis and requirements. Yield estimation (bud dissection, single node cuttings and Modelling). Fruit sampling, maturity assessment and harvesting.

Field and laboratory based plant/grapevine physiology:  Leaf and whole vine photosynthesis using Licor 6400 and whole-vine gas exchange systems.  Leaf porometry and water potential.  Vine sapflow using Heat pulse and sap exudation systems.  Carbohydrate and plant biomass manipulation using leaf removal, girdling, shading and cropload alteration techniques.  Specialised non-destructive vine sampling for nutrient and carbohydrate reserve status.  Environmental temperature logging.

Laboratory based management and analytical skills:  General laboratory management, purchasing and instalment of laboratory equipment, ordering supplies and maintenance of equipment. Grape fruit and juice preparation and analysis - brix (soluble solids), pH, titratable acidity, malic acid and potassium kit testing, Anthocyanin, Methoxypyrazine, Thiol precursor preparation.  Small batch wine making and wine sensory evaluation panellist. Plant carbohydrate analysis - soluble sugar and starch using enzyme and colourimetry methods.  Metrohm and Metler Toledo autotitration systems.  Unicam Helious fixed and scanning Spectrophotometry, Licor leaf area meter, Minolta SPAD leaf chlorophyll/greenness  Plant material freeze drying and grinding (rocklabs grinders).

Current Research

Jeff is currently involved in three research program areas; New Zealand Sauvignon Blanc (University of Auckland), Grapevine Carbohydrate (New Zealand Wine Growers) and Grapevine Variation (PQA - Foundation Research Science and Technology). Specific research projects within the program areas include the following:

• Bennett, J.S.; Trought, M.C.T.; Agnew, R.H. and Greven, M. (2007)  The impact of differences in soil type on vine phenology, growth and fruit composition of Sauvignon Blanc in a Marlborough vineyard.  Proceedings of the 13th Australian wine industry technical conference, 28 July to 2 August 2007, Adelaide, Australia.
• Bennett, J.S. and Trought, M.C.T. (2007)  The influence of training system on the yield and fruit composition of cool climate Marlborough Sauvignon Blanc.  Proceedings of the 13th Australian wine industry technical conference, 28 July to 2 August 2007, Adelaide, Australia.
• Bennett, J.S.; Trought, M.C.T. and Brady, J. (2006)  The influence of training system on the performance of cool climate Marlborough Sauvignon Blanc grapevines.  Proceedings of the 6th International Symposium on Cool Climate Viticulture and Oenology, 16-20 February 2006, Christchurch, New Zealand.
• Bennett, J.; Jarvis, P.; Creasy, G. and Trought, M.C.T. (2005) 

  Influence of defoliation on over-wintering carbohydrate reserves, return bloom and yield of mature Chardonnay grapevines.  American Journal of Enology and Viticulture, 56 No. 4 : 386-393