Influence of Arbuscular Mycorrhizal Fungi on the Growth and Development of Micropropagated Rubus fruticosus 'P45' Plants during Acclimatization

Blackberry (Rubus fruticosus L.) is an important fruit-yielding crop that is propagated by tissue culture. Ex vitro transplantation is a critical step in blackberry micropropagation. This study explored the usefulness of the mycorrhization of micro -propagated blackberry plants to enhance growth and development during the accli-matization stage. Two arbuscular mycorrhizal fungi (AMF), namely, Gigaspora margarita and Gigaspora albida, were mixed in equal proportions and used to treat the acclimatizing blackberry plants. The AMF-treated plants were taller (15.33 cm) and had more leaves (14.33/plantlet), more leaf area (143.66 cm2/plantlet), and shoots with higher fresh (2.76 g/plantlet) and dry (0.77 g/plantlet) weights. These plants also showed the highest values for the total root length (752.64 cm/plantlet), surface area of roots (733.03 cm2/plantlet), and fresh and dry root biomass values (1.21 g/plantlet and 0.295 g/plantlet, respectively). Additionally, CO2 assimilation, stomatal conduc-tance, and transpiration rates were higher in AMF-treated plants than in the control plants. These results emphasize the importance of treating micropropagated plants with AMF during the acclimatization stage.