The aim of this work was to evaluate the fruit damage tolerance in different peach tree genotypes after natural freeze. The frost happened on September 5, 2006, and the minimum temperature, 1.5 meters over soil, was -1.06ºC. Twenty- eight peach tree genotypes, in different stages of development, were evaluated, in a completely random design, in three replication (plants) and six branches by plants. Immediately after frost, we measured the number of fruits per branches, average fruit suture diameter, percentage of sprouts and percentage of twigs in formation. A second evaluation was accomplished fifteen days after the first one in order to assess the percentage of fruit drop and the average remaining fruit suture diameter. Genotypes with good leafing and hard pit (endocarp) during frost have freeze tolerance; fruits with suture diameter lass than 20 mm are susceptible to frost damage, while fruits with suture diameter superior to 30 mm are tolerant.
freeze injury; cold damage; fruit set; Prunus persica
