Loveys, Brian R. and Theobald, Julian C. and Jones, Hamlyn G. and McCarthy, Michael G. (2008) An assessment of plant-based measures of grapevine performance as irrigation scheduling tools. Acta Horticulturae, 792. pp. 421-427. ISSN 0567-7572
Full text not available from this repository.Abstract
A number of plant-based measures of performance have been assessed with a view to developing a simple, cost-effective means to determine grapevine response to irrigation. Two methods in particular were able to reliably differentiate between vines receiving different irrigation treatments and show promise as methods capable of development into practical irrigation scheduling tools. These were measurement of pre-dawn leaf water potential and the calculation of a canopy conductance index (Ig) based on the temperatures of the leaf canopy measured with an infrared thermometer and the temperature of filter paper reference surfaces. Other techniques were also assessed and these included measurement of stomatal conductance with a porometer and midday leaf water potential. Techniques that relied on fixed pieces of equipment were at a disadvantage because they allowed only a small number of vines to be measured and the cost was high. On the other hand, techniques using portable equipment such as a pressure chamber or an infrared thermometer allowed many measurements to assess both the spatial and temporal variation in measured parameters.