FRUIT PIGMENTATION AND ABSCISSION RATE OF FIELD PRIMOCANE-FRUITING RED RASPBERRY AFTER EXPOSURE TO AN AUTUMN FROST

Autumn freezes occur frequently in the midwestern United States before primocane-fruiting red raspberry fruit mature.
Experiments were conducted in 1992 at the Iowa State University, Horticulture Station in Ames, Iowa, to investigate the influence of cold temperature injury on raspberry fruit pigmentation and abscission rate.
On 28 Sept., 1992, six color stages (dark red, red, pink, mottled, yellow and green) of fruit of two cultivars, ‘Heritage’ and ‘Redwing’, were tagged.
A freeze occurred the subsequent night with temperatures at -1.11 °C for a time period of >3 hr.
Tagged fruit were evaluated from 29 Sept. through 11 Oct. for color stage and abscission. ‘Heritage’ and ‘Redwing’ raspberry fruit at all stages except those that were initially green matured under field conditions, despite the freeze. ‘Redwing’ fruit did not develop color as quickly as ‘Heritage’ fruit.
The green color stage fruit did not develop to full pigmentation or abscise from the receptacle within a 13 day-period after the frost.

VI International Symposium on Rubus and Ribes

Gail R. Nonnecke, M. R. Wannund, P. Perkins-Veazie

https://doi.org/10.17660/ActaHortic.1993.352.25