TRANSGRESSIVE SEGREGATION FOR WINTER CHILLING REQUIREMENT IN THE RED RASPBERRY CULTIVAR MALLING EXPLOIT

Cultivars of red raspberries adapted to grow in most parts of the Northern Hemisphere do not perform satisfactorily in the central highlands of Mexico at Chapingo (19°21′ N; and 2,250 m altitude) because of lack of sufficient cold to break the winter rest resulting in delayed foliation, blossoming and extended harvest season.

Open-pollinated progenies of the red raspberry ‘Malling Exploit’ fall outside the range of the parents for traits such as bud break, foliation and fruit production. ‘Malling Exploit’ buds break on April 4 with fruiting about May 30; the segregating population buds break from January 30 through April 9 with fruiting from April 30 through June 11. Some individuals turned out to be very productive and had large fruits with good quality.
Promising seedlings have been selected for their low winter cold requirement, needed to give uniform bud break after warm winters and vigorous growth.

Symposium on Breeding and Machine Harvesting of Rubus

F. P. Barrientos, Jorge A. Rodriguez

https://doi.org/10.17660/ActaHortic.1980.112.2