Low temperatures affect avocado plants and their response varies according to genetic traits. Plant physiologists of Londrina State University (Brazil) have investigated the cold stress of avocado cultivars based on visual, physiological, and biochemical criteria for evaluating freezing injury in these plants.

For the study, Geada, Fortuna, Fuerte, Quintal, Margarida, and Primavera avocado cultivars were subjected to temperatures of −2.5, −4.0, −5.0, and −6.0 °C for 1 h in a growth chamber. Their responses to cold stress were evaluated on the basis of visual damage score, photosynthetic rate, water pressure potential, protein content and enzymatic activity.

"The evaluations based on the plants water pressure potential, total protein content, catalase activity, photosynthetic rate, and visual damage score resulted efficient parameters in estimating the effects of cold stress in avocado plants. Additionally, photosynthesis and visual damage score were significantly correlated in all evaluations, enabling classification of the cultivars in terms of response to cold stress - the scientists explain - We have found that Fuerte is the most tolerant cultivar followed by Geada. The Primavera is the most sensitive cultivar".