PRODUCTION AND DRY MATTER ACCUMULATION IN STRAWBERRY (Fragaria x ananassa DUCH.) ON SUBSTRATES TREATED WITH METAM SODIUM OR MYCORRHIZA

In the strawberry (Fragaria x ananassa Duch.) industry, soil disinfection is mainly done by chemical methods. Due to the potential negative effects from soil disinfectants to the environment, less aggressive products or alternative systems such as growing on substrates are currently being studied; however, there is not enough information on the effect that these alternatives have on plant performance. The objective of this study was to evaluate the effect of the substrate treated before planting with metam sodium (MS) or by inoculation with mycorrhiza on yield and accumulation of dry matter of the Zamorana and Festival strawberry cultivars. Plants grown on substrates prepared with peat-moss and perlite, with or without compost and treated or not with MS or mycorrhiza were randomly distributed following a 3 x 2 x 2 factorial arrangement (substrate treatment, mixture of media and cultivars) into a glasshouse. Neither MS nor mycorrhiza significantly affected the yield components nor the dry matter distribution in the plant organs. The addition of compost to the substrate did not affect the yield or the number of fruits per plant either, but resulted in a lower weight of the fruit (11.3 g) compared to substrates without compost (12.1 g, P < 0.03). A reduction of 46.0 % (P < 0.0001), 15.2 % (P < 0.0189) and 12.4 % (P < 0.0195) was also observed in accumulated dry matter in root, leaf and total, respectively, in plants grown with compost. Zamorana had higher yield and fruit weight than Festival, with 410.2 vs. 345.5 g/plant (P < 0.006) and 12.8 vs. 10.6 g/fruit (P < 0.0001), respectively. Strawberry production in the studied substrates does not require prior treatment of the substrates; Zamorana shows better potential than Festival for production on substrate because of its higher yield and fruit weight.