Postharvest infection of highbush blueberries following contact with infested surfaces

Abstract

The effects of inoculum, surface wetness, and stem scar on postharvest fungal infection of highbush blueberry (Vaccinium corymbosum L.) fruit were evaluated by exposing berries of the cultivars Bluechip (small, dry stem scar) and Blueray (large, wet stem scar) to infested and noninfested surfaces under wet or dry conditions. Rots caused by Colletotrichum gloeosporioides (Penz.) Penz. and Sacc. in Penz. and Alternaria tenuissima (Kunze:Fr.) Wiltshire were evaluated. Field-harvested berries stored for 7 days at 21°C resulted in baseline infection levels of 1.5% ('Bluechip') and 18.7% ('Blueray') for C. gloeosporioides, and 10.1% vs. 28.9%, respectively, for A. tenuissima. Wet stem scars, infestation of handling surfaces, and addition of moisture were all responsible for increasing postharvest rots; however, most of the significant increases in rots occurred with a combination of two or more of these factors.