Proline and hydroxyproline containing cell wall proteins of red raspberry (Rubus idaeus L.) cane cortex

Abstract

The formation of insoluble wall bound proline-rich proteins (PRPs) and hydroxyproline-rich glycoproteins (HRGPs) in relation to the growth stage and developmental changes was examined in red raspberry primocane cortex. Two cultivars - 'Latham' and 'Malling Promise' - differing in growth intensity and in sensitivity to biotic stress were used for the experiments. The level of insoluble cell wall bound PRPs of the cortical tissues was almost similar in the course of the plants growth period. HRGPs were significantly higher at the end of the vegetation season (August/September), especially in 'Malling Promise'. The plant sensitivity to biotic stress, based on the response to the fungus Didymella applanata changed in the period of vegetative growth. At the end of summer the both cultivars became more resistant. It has been inferred that the insolubilization of wall PRPs and HRGPs was responsible for the acquiring resistance to D.applanata by 'Malling Promise', which was previously very susceptible to this fungus.