Variability in Rubus flower morphology

F.R. Luz, T. Valdiviesso, M.F. Roque, C.S. Trindade, P.B. Oliveira
In southern Portugal’s mild climate, yield loss associated with fruit rot caused by Cladosporium spp. is becoming a growing concern for fall red raspberry production. Although little is known about this disease it is generally linked to fall and winter specific weather conditions that reduce plant transpiration during harvest. Insects such as Drosophila suzukii may also have a role facilitating pathogen infection. Some growers have reported that cultivars with wider open flowers apparently are less susceptible to the disease. To explore further this hypothesis that Cladosporium fruit rot expression may be mitigated by the disposition of the different flower parts (relative position of anthers, ovules and nectaries) and full bloom opening a study was set up aiming to explore Rubus flower morphology and its differences as a first step to understand if this trait could help prevent the severity of this disease. Flowers from raspberry and blackberry of different cultivars from Rubus breeding programs were characterized and the differences were categorized. Flower morphology could be one trait to consider when selecting cultivars less vulnerable to Cladosporium in autumn/winter production.
Luz, F.R., Valdiviesso, T., Roque, M.F., Trindade, C.S. and Oliveira, P.B. (2023). Variability in Rubus flower morphology. Acta Hortic. 1381, 97-100
DOI: 10.17660/ActaHortic.2023.1381.13
Rubus idaeus, Rubus fruticosus, fruit disease, breeding program, southwest Portugal

Acta Horticulturae