Acclimatization of micropropagated plantlets of ‘Imperial’ pineapple

Abstract

The ‘Imperial’ pineapple cultivar stands out in the Brazilian scenario as an alternative for most of the production areas where the fusariosis disease causes high losses. The low availability of planting material has been one of the main limitations for pineapple growers and tissue culture has to be used intensively for meeting the demand of good quality planting material. The acclimatization period has been a critical period in this process, determining evolution of plant development and time needed for obtaining plantlets adequate for transfer to the field. This work was carried out to determine the effects of substrates and fertilizer doses on ‘Imperial’ pineapple plantlets growth during acclimatization. Treatments studied were combinations of the substrates Plantmax®, Plantmax® plus soil, Plantmax® plus carbonized rice straw, Plantmax® plus soil and carbonized rice straw, with the Osmocote® fertilizer at 0, 3, 6, 9 and 12 kg/m-3 in a 4 x 5 factorial scheme set up in randomized blocks with four replications. 120 days after transfer of plantlets to the greenhouse the following variables were evaluated: shoot and root length, root number, shoot and root dry mass. Plantmax substrate alone was superior to its combination with soil and carbonized rice straw, resulting in better plant growth during the acclimatization period. Plant growth was improved by application of Osmocote fertilizer.