Apple Chemical Fruit Thinning in Cuauhtemoc, Chin., Mexico

摘要

Chemical thinning trials conducted on the apple cultivars 'Golden Delicious' and 'Red Chief Delicious' at Chihuahua in Mexico are described. NAA sprays, either as the potassium or sodium salt, proved the most effective in thinning both cultivars. Sprays of carbaryl, ethephon and fish oil proved largely ineffective. Mexico's most important apple production area is located in the northwest region of Chihuahua state. 'Golden Delicious' and some mutations of 'Red Delicious' are the most widely planted apple cultivars in this region. Fruit thinning consists of the removal of a proportion of the crop during the first stages of fruit development. This is an important practice in apple production since it increases the fruit size and minimizes alternate bearing. Thinning can be accomplished by hand or by the use of chemicals. Chemical thinning has the advantage of reducing the time and the labor cost (Greene, 2002 and Dennis, 2002). 'Golden Delicious' and 'Red Chief Delicious' have proved to be cultivars that are difficult to thin adequately with chemicals. The objective of this work was to evaluate different chemicals for their ability to thin 'Golden Delicious' and 'Red Chief Delicious' apples in the northwest region of Chihuahua state.