Postharvest Evaluations of Avocado Fruit from Reciprocal Crosses of ‘Hass’ and ‘Bacon’

In the United States, California and Florida are the top avocado producing states, but grow avocados with different genetic backgrounds. California grows cultivars of Guatemalan and Mexican races, and their hybrids, while Florida grows cultivars of West Indian race and West Indian-Guatemalan hybrids that are more suited for humid, tropical climates. A population of California reciprocal crosses of ‘Hass’-‘Bacon’ hybrids was planted at the USDA-ARS, Fort Pierce to find selections with good horticultural and postharvest quality traits well adapted to east-central Florida. This area of Florida experiences more frequent freeze events than the current south Florida avocado production zone. Extensive phenotypic data on fruit quality (fruit weight, seed weight, fruit size and diameter, oil content, number of fruits per tree, dry matter, whole fruit firmness) was collected over the 2013-2015 growing seasons. Peel color was measured to find selections that turned darker upon ripening as the color change tends to mask minor surface imperfections. Upon ripening, all avocados exhibited a loss in green color expressed by lower h¢ª values throughout all three years, and some appeared to become yellow-green with hue angle values close to 90. Edible and non-edible portions of the fruit were evaluated according to presence and absence of disorders. The highest mean severities in 2013 were observed in disorders such as uneven ripening, vascular browning, pink staining, and tissue breakdown. Uneven ripening and tissue breakdown had the highest mean severities in 2014 and seed cavity browning was the most common disorder in 2015. Fruit weight was highly variable, ranging between 96.8 and 418.3 grams. Fruit weight loss rate ranged between 0.14% and 0.71% per day over six days. Mean dry matter ranged from 15.5 to 34.4% (unripe) and from 14.5 to 36.0% (ripe) in 2013, from 17.4 to 35.3% (unripe) and from 13.2 to 29.6% (ripe) in 2014, from 12.7 to 29.9% (unripe) and 16.2 to 25.4% in 2015. In 2013, fruit had an average initial whole fruit firmness of 126 N and 144 N during two harvests and reached full ripe stage (20-30 N) between 12 and 16 days after harvest. In 2014 and 2015, initial average whole fruit firmness was 135 N and 136 N, respectively, and reached full ripeness within 10 to 14 days after harvest. Promising selections with potential as cultivars were identified with good horticultural traits and fruit quality.