The Chilean apple industry has a production area of 37,194 ha (ODEPA, 2007), producing ≈1.4 million tons of apples annually, making it one of the major apple industries in the world. Its exports were over 44 million boxes to more than 70 countries during 2009–2010. This accounts for ≈60% of total apple production in the country. The remaining 40% cannot be exported as a result of lack of quality expressed as: poor red color, sun damage, small size, and pre- and postharvest physiological disorders. This is attributed to inadequate cultivar/rootstock combinations and microclimate limitations where different apple cultivars have been traditionally grown in Chile.
The main apple cultivars belong to the Gala and Red Delicious groups, ‘Granny Smith’, ‘Fuji’, ‘Cripp's Pink’, and ‘Braeburn’. Seventy percent of the production is concentrated in the VI (Libertador Bernardo O'Higgins) and VII (Maule) regions in Chile. Nevertheless, during the last decade, new plantings have been shifting south, VIII (Bio-Bio) and IX (Araucania) regions, which are believed to be better suited for apple production as a result of their milder temperature (less environmental stress), but have also a lack of experience with newly introduced cultivars and rootstocks. M.M.106 was the main rootstock used in Chile until Year 2000, after which M.9 and its sub-clones were introduced commercially for their precocity and vegetative characteristics that facilitated cultural practices such as hand thinning and pruning. M.9. plantings have steadily increased since then adding another challenge to growers, especially to those from the south of Chile (Carrasco, 2003). With high input costs (as high as US$ 25,000/ha in fifth-leaf trees), Chilean growers are running a risk in planting new cultivars/rootstock combinations with poor local research. In 2002, a government–industry-funded project (FONDEF) was initiated to evaluate performance of most important apple cultivars grown in Chile in a multisite experiment across different apple-growing areas. Traditional apple-producing areas (VI, VII regions) were compared with the new and expanding ones further south (VIII, IX regions). Malling-Merton (M.M.) 106 and M.9 EMLA rootstocks were also compared.
Barden, J.A. & Marini, R.P. 2001 Comparison of methods to express growth, size, and productivity of apple trees J. Amer. Pom. Soc. 55 251 256
Lespinasse, J.M. & Lauri, P.E. 1999 Integration des nouveaux concepts de conduite dans le systeme Solaxe Revue Suisse Vitic. Arboric. Hort. 31 167 171
ODEPA 2007 VII Censo Agropecuario, 2007 Ministerio de Agricultura, Gobierno de Chile, Santiago de Chile 25 Sept. 2010 <http//www.odepa.gob.cl>.
Stanley, C.J., Tustin, D.S., Lupton, G.B., McArtney, S., Cashmore, W.M. & de Silva, H.N. 2000 Towards understanding the role of temperature in apple fruit growth responses in three geographic regions within New Zealand J. Hort. Sci. Biotechnol. 75 413 422
Trillot, M., Masseron, A., Mathieu, V., Hutin, C. & Lespinasse, Y. 2002 Le pommier Editions Centre technique interprofessionnel des fruits et legumes, Paris, France
Webster, A.D. 1995 Rootstock and interstock effects on deciduous fruit tree vigour, precocity, and yield productivity N. Z. J. Crop Hort. Sci. 23 373 382
Webster, A.D. 2005 Sites and soil for temperate tree-fruit production: Their selection and amelioration 12 25 Tromp J., Webster A.D. & Wertheim S.J. Fundamentals of temperate zone tree fruit production Blackhuys Publishers Leiden, The Netherlands
Webster, A.D. & Wertheim, S.J. 2003 Apple rootstocks 91 124 Ferree D.C. & Warrington I.J. Apples: Botany, production and uses CABI Publishing Wallingford, UK
Westwood, M.N. & Roberts, A.N. 1970 The relationship between trunk cross-sectional area and weight of apple trees J. Amer. Soc. Hort. Sci. 95 28 30
Yuri, J.A., González-Talice, J., Verdugo, J. & del Pozo, A. 2010 Responses of fruit growth, quality, and productivity to crop load in apple cv. Ultra Red Gala/MM111 Sci. Hort. 127 305 312