John A. Cline

John Cline
Associate Professor

Email:

Phone:

(519) 426-7127 x331

Fax:

(519) 426-1225 x905

Education:

B.Sc. University of Guelph;
M.Sc. Michigan State;
Ph.D. University of London (UK)

Location:

Simcoe Station

Room:

Simcoe
1221 ECB

APPLES
The Ontario apple industry, valued at approximately $400 million, is the predominant tree fruit crop grown in Ontario. The wide diversity of growing regions, cultivars, rootstocks, and soil types influence the cultural and production of this crop and create a challenging blend of research needs.

The Horticultural Experiment Station, Simcoe, has 10+ hectares of orchard dedicated to apple research. Research and extension interests of this project are directed toward gaining and communicating a better understanding of apple tree physiology. Recognizing the factors that influence yield and fruit quality are one of its primary thrusts. Studies focus on the evaluation of new cultivars for suitability under Ontario's soil and climatic regime that can generate high market returns and/or develop niche markets and products. New cultivars that show resistance to pests and disease are being sought in order to reduce the amount of agri-chemicals and pesticide residues. Studies also focus on utilizing dwarfing Malus rootstocks and their influence on precocity, cropping efficiency, and tree vigour, and the performance of various cultivar/rootstock combinations in various intensive orchard production systems. Research on advanced horticultural technologies including new orchard training systems, advanced irrigation systems, and advances in the plant bio-substances such as gibberellins to regulate flowering and fruiting to minimize hand thinning, and prohexidione-calcium to reduce vegetative growth, are being actively pursued. Soil management studies to evaluate the benefits of soil amendments recycled from agricultural and industry sources on tree establishment, cropping, and ag-sustainability, and plant nutrition studies focusing on the improvement of fruit quality and yield are also an integral part of this research project.

Collectively, our research endeavors are devoted to helping Ontario apple growers produce premium quality fruit consistently, competitively and profitably, using sustainable agricultural practices.

Project Goals:                                                   

  1. To provide Ontario orchardists the technical information required to produce premium quality fruit consistently, competitively, and profitably using sustainable orchard practices.
  2. To enhance our understanding of the physiological processing influencing tree growth, flowering, and fruit productivity.

Research Objectives:

  1. Tree biology in relation to plant bioregulators (PBR) to regulate cropping, improve production efficiency and fruit quality.
  2. Beneficial use of organic amendments and irrigation for reducing soil-borne disease and use of herbicides, improving fruit quality and plant health, minimizing soil groundwater contamination, and enhancing water conservation.
  3. Quantify the performance of various rootstock/scion combinations under different orchard, environment and management systems.
  4. Optimizing tree fruit mineral nutrition for enhanced fruit quality, tree growth, and with minimal consequence on the environment.
  5. Identify adaptable tree fruit cultivars with a range of ripening dates useful for fresh market production.

CHERRIES & PEACHES

The value of the Ontario tender fruit industry, estimated to be valued at approximately $100 million, and next to apples, is the most important tree fruit crop in Ontario. The wide diversity of tender fruit crops, cultivars, rootstocks, and soil types which influence peach, nectarine, cherry, and apricot production creates a unique and challenging blend of research needs to help solve the industry's short and long-term problems. Research and extension interests of this project are directed toward gaining and communicating a better understanding of the physiology processes affecting growth, yield and fruit quality. Research will focus on utilizing dwarfing precocious Prunus rootstocks and to determine their influence on cropping efficiency, tree longevity vigour, and fruit quality. New research on advanced horticultural technologies including new central leader higher density (spindle) training systems, advanced irrigation and organic mulching systems, and plant bio-substances such as gibberellin, ethylene biosynthesis promoters and inhibitors to influence flowering and fruiting are being actively pursued. Our research endeavours are devoted to helping Ontario tender fruit growers the ability to produce premium quality fruit consistently, competitively and profitably, using sustainable agricultural practices.

Canadian tender fruit production is concentrated in Ontario (70%) and British Columbia (30%) with an annual production of 66, 550 MT and a five year average farm-gate value of nearly $59 million (Anonymous, 2002). Domestic production of peaches, plums and nectarines account for about 60%, 17% and 4%, respectively of the total Canadian supply of tender fruits. Imports of tender fruit, (mostly from the United States) however exceed domestic production by a ratio of 2:1; and have a marketed value of $188 million or 75% of the total market value of tender fruit sales in Canada. This deficit in market value (domestic value is 25% of the value of imports) and trade (32% of total consumption is produced domestically) indicates there is real potential for the domestic supply to offset imports when competing within similar production seasons.

Research Objectives

  1. Fruit Tree Water Relations and the Physiology of Rain-Induced Cracking of Sweet Cherries
  2. Research Based Evaluation of Peach Tree Forms
  3. Tree physiological research leading toward better management practices for stone fruit orchards
  4. Quantify the performance of various Prunus rootstock/scion combinations under different orchard, environment and management systems.
  5. Fruit tree biology in relation to plant bioregulators (PBR) to regulate cropping, improve production efficiency and fruit quality

Courses:

HORT*4420 Fruit Crops
PLNT*6400 (W) Seminar

Relevant Links:

Selected Publications:

Cline, J. (2017). Interactive effects of 6-BA, GA4+7 and prohexadione-calcium on 'Gala' apples. Canadian Journal of Plant Science. DOI: 10.1139/CJPS-2016-0314.

Cline, J. (2016). Prohexadione-Ca and Ethephon Suppress Shoot Growth of Sweet Cherries (P. Avium). Canadian Journal of Plant Science. DOI: 10.1139/CJPS-2016-0271.

Cline, J. & C. Bakker. (2016). Prohexadione-calcium, ethephon, trinexapac-ethyl and maleic hydrazide reduce extension shoot growth of apple. Canadian Journal of Plant Science. DOI: 10.1139/CJPS-2016-0106.

Marini, R. P., W.R. Autio, B. Black, J.A. Cline, C.W. P Jr., et al. (2016).  Time required for classifying rootstock vigour in multi-location rootstock trials. Journal of the American Pomological Society. 70 (2): 82-91.

Arseneault*, M. & J. Cline. (2016). A review of apple preharvest fruit drop and practices for horticultural management. Scientia Horticulturae. 211: 40-52. DOI: 10.1016/j.scienta.2016.08.002.

Marini, R. P., W. Autio, B. Black, J.A. Cline, W. Cowgill, et al. (2015). Classifying Rootstock Vigor in Multi-location Rootstock Trials. Journal of the American Pomological Society. x (x): xx-xx.

McClure, K. & J. Cline. (2015). Mechanical blossom thinning of apples and influence on yield, fruit quality and spur leaf area. Canadian Journal of Plant Science. 95 (5): 887-896. DOI: 10.4141/CJPS-2014-421.

Sauertig, K. & J. Cline. (2013). Mechanical blossom thinning of 'Allstar' peaches influences yield and quality. Scientia Horticulturae. 160 (243): 250.

Marini, R.P., W.R. Autio, B. Black, J. Cline, W.R. Cowgill, Jr., R.M. Crassweller, P.A. Domoto, C. Hampson, R. Moran, R.A. Quezada, T. Robinson, D.L. Ward, and D. Wolfe. (2013). Return Bloom on 'Golden Delicious' Apple Trees as affected by Previous Season's Crop Density on Three Rootstocks at 11 Locations. Journal of the American Pomological Society. 67: 72-79.

Duyvelshoff, C. and J.A. Cline. (2013). Ethephon and Prohexadione-Calcium Influence the Flowering, Early Yield, and Vegetative Growth of Young ‘Northern Spy’ Apple Trees. Scientia Horticulturae. 151: 128-134.

Sauerteig, K.A. and J.A. Cline. (2013). Mechanical blossom thinning of ‘Allstar’ peaches influences yield and quality. Scientia Horticulturae. In Press.

Cline, J.A., D. Neilsen, G. Neilsen, R. Brownlee, D. Norton, H. Quamme. (2012). Cold Hardiness of New Apple Cultivars of Commercial Importance in Canada. Journal of the American Pomological Society. 66 (4): 174-182.

Marini, R.P., W.R. Autio, B. Black, J.A. Cline, R. Crassweller, P. Domoto, C. Hampson, R. Moran, R.A. Parra-Quezada, T. Robinson, M. Stasiak, D. Wolfe. (2012). The Influence of Crop Density on Annual Trunk Growth of ‘Golden Delicious’ Apple Trees on Three Rootstocks at 11 Locations. Journal of the American Pomological Society. 66 (4): 183-195.

Cline, J. and D. Norton. (2012). Performance of 17 Peach and Nectarine Cultivars in a Southern-Ontario, Non-traditional Growing Region. Journal of the American Pomological Society. 66 (3) 133-141.

Marini, R.P., R. Crassweller, W.R. Autio, B. Black, J.A. Cline, P. Domoto, C. Hampson, R.A. Parra-Quezada, T. Robinson, M. Stasiak, D. Wolfe. (2012). Summary of the NC-140 Apple Physiology Trial: The Relationship Between ‘Golden Delicious’ Fruit Weight and Crop Density at 12 locations as Influenced by Three Dwarfing Rootstocks. Journal of the American Pomological Society. 66 (2): 78-90.

Autio, W., T.L. Robinson, T. Bradshaw, J. Cline, R.M. Crassweller, C.G. Embree, E. Hoover, G. Lang, J. Masabni, M.L. Parker, R. Perry, G.L. Reighard, J. Schupp, and M. Warmund. (2011). Performance of several dwarfing rootstocks with 'Fuji' and 'McIntosh' as scion cultivars in the 1999 NC-140 dwarf apple rootstock trials. Acta Horticulturae. 903: 319-326.

Autio, W., T.L. Robinson, J. Cline, R.M. Crassweller, C.G. Embree, E. Hoover, G. Lang, J. Masabni, M.L. Parker, R. Perry, G.L. Reighard, and M. Warmund. (2011). Performance of several semi-dwarfing rootstocks with 'Fuji' and 'McIntosh' as scion cultivars in the 1999 NC-140 semi-dwarf apple rootstock trials. Acta Horticulturae. 903: 327-334.

Reighard, G., T. Beckman, R. Belding, P. Byers, J.A. Cline, W. Cowgill, R. Godin, R.S. Johnson, J. Kamas, H. Larsen, T. Lindstrom, M. Newell, D. Ouellette, R. Pokharel, L. Stein, K. Taylor, C. Walsh, D. Ward, and M. Whiting. 2011. Six-year performance of 14 rootstocks at 11 sites in the 2011 NC-140 Peach Trial. Journal of the American Pomological Society. 65 (1): 26-41.

Johnson, S.R., Anderson, W. Autio, B. Black, P. Byers, J.A. Cline, W. Cowgill, C. Chavex-Gonzales, W. Cowgill, R. Godin, G. Greene, M. Kaps, H. Larsen, T. Lindstrm, D. Miller, M. Newell, D. Ophardt, D. Ouellette, R. Parra-Quezada, R. Pokharel, G. Reighard, T. Robinson, J. Schupp, L. Stein, K. Taylor, C. Walsh, D. Ward, M. Warmund, and M. Whiting. (2011). Performance of the 2002 NC-140 Cooperative Peach Rootstock Planting. Journal of the American Pomological Society. 65 (1): 17-25.

Taheri, A., J. Subramanian, J. Cline, M.N. Raizada, and P.K. Pauls. (2012). A WD-repeat gene from peach (Prunus persica L.) is a functional ortholog of Arabidopsis thaliana TRANSPARENT TESTA GLABRA1. In Vitro Cellular and Developmental Biology – Plant. 48 (1): 23-29. DOI: 10.1007/s11627-011-9390-3.

Taheri, A., J.A. Cline, J. Subramanian, and P.K. Pauls. (2012). Ethephon-Induced Abscission of ‘Redhaven’ Peach. American Journal of Plant Sciences. 3: 295-301.

Cline, J.A., G. Neilsen, E.J. Hogue , S. Kuchta, and D. Neilsen. (2011). Spray-on-Mulch Technology for Intensively Grown Irrigated Apples Orchards: Influence on Tree Establishment and Early Yields. HortTechnology. 21 (4): 309-411.

Autio, W.R., T.L. Robinson, B. Black, T. Bradshaw, J.A. Cline, R.M. Crassweller, C.G. Embree, E.E. Hoover, R.S. Johnson, G. Lang, M.L. Parker, R.L. Perry, G.L. Reighard, J.R. Schupp, M. Stasiak, M. Warmund, and D. Wolfe. (2011). Performance of 'Fuji' and 'McIntosh' Apple Trees After 10 Years as Affected by Several Semi-Dwarf Rootstocks in the 1999 NC-140 Apple Rootstock Trial. Journal of the American Pomological Society. 65 (2): 21-38.

Autio, W.R., T.L. Robinson, B. Black, T. Bradshaw, J.A. Cline, R.M. Crassweller, C.G. Embree, E.E. Hoover, R.S. Johnson, G. Lang, M.L. Parker, G.L. Reighard, J.R. Schupp, M. Stasiak, M. Warmund, and D. Wolfe. (2011). Performance of 'Fuji' and 'McIntosh' Apple Trees After 10 Years as Affected by Several Dwarf Rootstocks in the 1999 NC-140 Apple Rootstock Trial. Journal of the American Pomological Society. 65 (2): 2-20.