Quality and Postharvest Behavior of Once-over Harvested Clingstone Peaches Treated with Daminozide1

Abstract

Abstract Succinic acid-2,2-dimethylhydrazide (daminozide) applied at 1800 ppm to 10-year-old ‘Babygold-5’ and ‘Babygold-8’ peach trees (Prunus persica (L.) Batsch) at pit hardening advanced fruit maturity and increased tolerance of low soluble solids fruit by improving flesh color. Fruit softening, the disappearance of flesh chlorophyll, and reductions in puree viscosity were the primary benefits obtained from the application of daminozide. Daminozide advanced maturation generally, rather than concentrating the fruit into a more uniform maturity class. Flesh color and acidity were highly correlated with loss of fruit firmness of both control and daminozide-treated fruit, but daminozide treated fruit improved in flesh color more rapidly than control fruit as firmness decreased. Acidity remained consistently higher for treated fruit at all firmness levels. The mechanism by which daminozide advanced maturity did not appear to be active during postharvest holding of these clingstone cultivars. Further ripening as a result of postharvest storage of both treated and control fruit occurred at about the same rate during a 2, 4 or 6 day period at 18°C.