Does the propagation technique affect phytochemical composition of raspberry and blackberry fruits?

Abstract

In Serbia, the dominant methods of vegetative propagation of raspberries and blackberries are by root suckering (raspberry) and tip layering (blackberry), and they represent standard propagation techniques. However, due to the possible contamination of such planting material with viruses and phytopathogenic fungi, obtaining plants from tissue culture in vitro is becoming increasingly important. Therefore, the aim of this study was to investigate the fruit quality according to their chemical composition, emphasising the content of bioactive compounds in fruits of raspberry (Rubus idaeus L.) 'Meeker' and blackberry (Rubus fruticosus L.) 'Čačanska Bestrna' from plants propagated in the field by standard technique (ST) and grown in vitro micropropagation tissue culture (TC). A three-year experiment included the determination of the main fruit quality parameters (soluble solids, sugars, and total acids) by standard methods. The identification and quantification of phenolic compounds (protocatechuic, 4hydroxybenzoic, ellagic, gallic, p-coumaric, caffeic and ferulic acids, quercetin, cyanidin, and pelargonidin) were performed using high-performance liquid chromatography (HPLC). The obtained results showed that the origin of the planting material did not significantly affect the quality of the fruits in terms of primary and secondary metabolites, except for 4-hydroxybenzoic acid in blackberries. This means that both (ST and TC) propagation methods allow obtaining fruits of equally good quality. Therefore, when choosing the type of planting material, other factors such as health, yield, and cost of planting material should be taken into account.