Articles
BEHAVIOUR OF SOME APPLE CULTIVARS IN THE SUBTROPICAL REGION OF SANTA CATARINA, BRAZIL
The annual mean temperature in Caçador is 16.6°C and the mean temperature in the winter is 13.2°C. The number of chilling hours (≤ 7.2°C) from May to September is 538, and the altitude is 960 m above sea level.
During 1980–87, 200 apple cultivars were tested under these climatic conditions with the objective of selecting cultivars for commercial planting, as well as for selecting parents for the apple breeding program.
All apple cultivars were evaluated through 20 phenological characteristics.
Results showed that in such a condition apple cultivars present several problems such as retarded and deficient foliation, low productivity, small fruit size and flattened fruit.
The use of chemicals to break bud dormancy in the spring can partially supply the chilling requirement, allowing some cultivars to grow quite well.
Some cultivars with very low chilling requirement such as Anna, Ain Shemer and Vered do not crop due to spring frost.
Those with low chilling requirement as Gala, Willie Sharp and Mollie’s Delicious, as well as those with intermediate chilling requirement such as Belle de Boskoop and Granny Smith crop quite well with chemical treatment for breaking dormancy of the buds.
Those apple cultivars with high chilling requirement such as Golden Delicious, Red Rome, Fuji and Jonagold all crop well after chemical treatment to break dormancy of the buds.
However, cultivar Fuji presents very uneven fruit shape and size.
The three apple cultivars most planted in Santa Catarina are Gala, Golden Delicious and Fuji.