Establishing micropropagation protocols for new strawberry (Fragaria × ananassa) breeding lines

Micropropagation remains an important tool for strawberry nursery production aimed at improving plant sanitary and genetic quality. To have this result without the risk to induce genetic and phenotypic variability efficient micropropagation, protocols for each genotype must be developed, mainly based on the use of proliferation substrates with low cytokinin content and a controlled number of subcultures. In addition, the in vivo bud sterilization is one of the critical steps for the establishment of high-quality proliferative explants, as well as acclimatization conditions for the efficient in vivo transfer of the micropropagated plants. Micropropagation technology is of high support for the fast development of new breeding material with high interest for the market. The aim of this study was to verify the different response to the in vitro establishment and proliferation of different strawberry (Fragaria × ananassa) genotypes derived from the breeding program developed at Ancona, University (Italy). The response to a standard sterilization protocol was tested on lateral and terminal buds of runners harvested from in vivo strawberry plants, in two different periods (June and September), and the genotype effect on in vitro explant proliferation at low-cytokinin concentration, was studied. The goal was to obtain healthy mother plants for starting in vivo propagation of new breeding selections.