Freezing injury and colonization of 'Redwing' red raspberries with ice-nucleation-active bacteria

• Published in: Journal of the American Society for Horticultural Science Vol. 120; no. 6; pp. 1041 - 1044
• Main Authors: Warmund, M.R. (University of Missouri, Columbia, MO.), English, J.T
• Format: Journal Article
• Language: English
• Published: 01.11.1995
• Subjects: ANALISIS TERMICO; ANALYSE THERMIQUE; BACTERIA; CALICE; CALIZ; CONGELACION; CONGELATION; DANOS POR LA HELADA; DEGAT DU AU GEL; DENSIDAD DE LA POBLACION; DENSITE DE POPULATION; ECOLOGIA; ECOLOGIE; ETAPAS DE DESARROLLO DE LA PLANTA; FRUITS; FRUTAS; GINECEO; GYNECEE; HABITAT; MADURACION; MATURATION; PIGMENTACION; PIGMENTATION; RUBUS IDAEUS; STADE DE DEVELOPPEMENT VEGETAL; TEMPERATURA; TEMPERATURE
• ISSN: 0003-1062; 2327-9788
• DOI: 10.21273/JASHS.120.6.1041

In 1993, ice-nucleation-active (INA) bacteria were isolated from 'Redwing' red raspberries (Rubus idaeus L. var. idaeus) at five pigmentation stages. Fruit were also subjected to thermal analysis to determine the ice nucleation temperatures. INA bacteria were recovered from nearly all fruit samples, and the bacterial populations tended to decrease with greater red color development (i.e., fruit maturation). However, the ice nucleation temperature was not affected by the stage of fruit pigmentation. In 1994, INA bacterial densities were similar among fruit at the three pigmentation stages sampled. INA bacteria were recovered more often from the calyx rather than the drupe surface of these fruit. INA bacteria also were detected on pistils of some fruit. Red and pink fruit, which were nucleated with ice, had greater receptacle injury than mottled, yellow, or green fruit, but INA bacterial densities apparently were not related to injury. Thus, the injury response of fruit at different pigmentation (or development) stages indicated that nonbacterial ice nuclei may be involved in freezing injury of developing raspberries