Grape production, new cultivars, trellis/spacing geometry, fertigation, rootstocks

Research Interests:

The viticultural research programme focuses on production efficiency for the juice, wine and table grape industry. Fundamental issues such as vine spacing, trellis design, pruning systems, rootstock choices, nutrition, irrigation and soil management are addressed at various levels - full scale commercial field trials and detailed single vine physiological studies -with the goal of integrating practical answers to production problems with rigorous academic studies. A balance is attempted between the juice and wine industry queries, as the answers may be different for similar problems in the two sectors. Grape breeding for disease and winter hardiness is also part of the general programme. At present, studies include:

1. trellising systems and their effect on shoot/fruit exposure and the subsequent effects on production, fruit quality , wine quality and various health-linked components.
2. spacing geometry and its effects on many of the above components as well as efficient vineyard management. An additional, more comprehensive trial has been planted off-station in co-operation with a large local winery to look at the economics and practicality of 6 row spacings and 4 vine spacings for the cultivar Pinot noir clone 115, a desirable Burgundian clone to be used for an ultra-premium line of wines.
3. rootstock trials are ongoing exercises for locally specific recommendations, but a large trial with 5 rootstocks and own-rooted vine is being used to examine nutritional and winter injury studies where crop load can be restricted and subsequent effects on fruit quality measured. This block also has possibilities for phylloxera studies.
4. land preparation and the improvement of physical soil quality with locally available amendments is underway. Details of the physical structure as well as the appropriate timing of amendment applications for the availability of nitrogen within the growing cycle of a perennial vine where low nitrogen is usually the key to quality will be the focus of these vines. An off-station trial is also underway to assess the impact of very high pH soils and the establishment of new vineyards with experimental rootstocks capable of tolerating pH 7.5
5. soil management and soil amendment application in commercial vineyards is the focus of another off-station trial encompassing 5 hectares. Application of organic nitrogen sources to improve vineyard soil structure, improve soil drainage and increase yields without excessive use of ammonium nitrate are part of a nutrient management plan study, in co-operation with the Ministry of Agriculture and Food. Again, nitrogen cycling in relation to the growing cycle of a perennial vine will be the focus of the in depth studies in this vineyard.
6. irrigation in juice grapes and the application of nitrogen through the irrigation water is underway in an off-station site, encompassing 2 hectares. Two systems of irrigation are being tested - drip and "leaky " buried tape. Efficient application of nitrogen in quantities acceptable in the juice industry, more driven by yield than the wine industry, are being applied at various appropriate phenological stages in the vine cycle. Stress indicators are being examined in the juice grapes being irrigated at present.
7. breeding grapes for cold and disease resistance has been the goal of the programme since 1913. New cultivars are required for the table grape industry, but demand for crisp flesh and seedlessness have taxed the winter hardiness of these lines. Disease resistance and winter hardiness are also critical for grape growing in distant parts of the province and interest is such that new trials are being planted in these areas. Advanced lines being developed for high colour are also being studied for inheritance of berry flesh as well as skin colouration and the mechanisms that perhaps control the expression of these colourants as well as related compounds such as resveratrol and its precursors.

Drip lines in young Concord vineyard for irrigation/fertigation trials.	Drip lines in young Concord vineyard for irrigation/fertigation trials.

Selected Published Manuscripts:

Vanden Heuval, J.E., E.D. Leonardos, J.T.A. Proctor, K.H. Fisher and J.A. Sullivan. (2002). Translocation and partitioning of 14C Photoassimilate from light and shade Adapted shoots in greenhouse grown chardonnay grapevines (Vitis vinifera). J. Amer. Soc. Hort. Sci. (accepted)

Staff, S.A., D.C. Percival, J.A.Sullivan and K.H. Fisher. (1997). Fruit zone leaf removal influences vegetative, yield, disease, fruit composition and wine sensory attributes of Optima and Cabernet franc. Can. J. Plant Sci. 77: 149-153.

Fisher, K.H., B. Piott and J. Barkovic. (1996). Adaptability of labrusca and French hybrid grape varieties to mechanical pruning and mechanical thinning. Proc. 4th Int. Cool Climate Enology and Viticulture Conference (Ed. T. Henik-Kling, T.E. Wolf and E.M. Harkness), Rochester, NY, IV:33-39.

Fisher, K.H., B. Piott and T. Tancock. (1996). Estimating Concord crops for machine thinning accuracy. yields. Proc. 4th Int. Cool Climate Enology and Viticulture Conference (Ed. T. Henik-Kling, T.E. Wolf and E.M. Harkness), Rochester, NY, IV:28-32.

Percival, D.C., K.H. Fisher and J.A. Sullivan. (1994). Use of fruit zone leaf removal with Vitis vinifera L. cv. Rielsing grapevines. Part I: Effect on canopy structure, microclimate, bud survival, shoot density and vine vigour. Am J. Enol. Vitic. 45:2:155-161.

Percival, D.C., K.H. Fisher and J.A. Sullivan. (1994). Use of fruit zone leaf removal with Vitis vinifera L. cv. Rielsing grapevines. Part II: Effect on fruit composition, yiled and occurrence of bunch rot (Botrytis cinerea Pers.:Fr.). Am. J. Enol and Vitic. 45:2:162-168.

Percival, D.C., J.A. Sullivan and K.H. Fisher. (1993). Effect of cluster exposure, berry contact and cultivar on cuticular membrane formation and occurrence of bunch rot (Botrytis cinerea Pers.:Fr.) with 23 Vitis vinifera L. cultivars. Vitis: 32:87-97.