Epigenetic variation and enhanced vegetative growth in micropropagated berry crops for wide adaptability and early berry production in northern environment

Berry crops in Vaccinium (blueberry, cranberry and lingonberry; Ericaceae), Fragaria (strawberry; Rosaceae) and Rubus (brambles: raspberry and blackberry; Rosaceae) genera are commercially and medicinally important worldwide. Blueberry, lingonberry, cranberry, cloudberry and huckleberry are native to the North. Their role in anti-ulcer, anti-inflammatory, anti-tumor and anti-oxidant activities is of significant importance for their high contents of health promoting bioactive components. Although in vitro culture on semi-solid and in liquid media in bioreactor systems has evolved multi-billion biotechnological approach for mass propagation of various crop plants, stresses in vitro can cause changes at molecular, physiological and/or biochemical levels leading to altered variation in morphology and bioactive components in micropropagated berry crops. These variations, also called somaclonal variation, can be genetic or epigenetic, and are dependent on factors like genotype, explant origin and type, chimeral tissue, media type, type and concentration of plant growth regulators, and environment and duration of culture. Somaclonal variation in micropropagated berry crops including enhanced vegetative growth and increaded berry production and antioxidant activity might be of practical application to the growers. This review deals with critical information for better understanding the epigenetic effects on morphology and antioxidant properties along with DNA methylation in micropropagated berry crops and covers the existing gap in literature.