The objective of this work was to select and to evaluate isolates of diazotrophic bacteria associated to pineapple (Ananas comosus (L.) Merril) plants in the development of micropropagated plantlets of cultivars pineapple in greenhouse. Plantlets from the Perolera cultivar have been submitted to inoculation with Asaia bogorensis (AB219) and were cultivated during 145 days on the following mixtures: carbonized rice hulls, leave dust from carnaúba (Copernica cerifera) palm tree, vermicompost; carbonized rice hulls, rip coir dust, vermicompost; and carbonized rice hulls, vermiculite, vermicompost. Plantlets of the Primavera cultivar had received bacterial inocules containing AB219 and bacteria related to Burkholderia cepacia (AB202 and AB213), while plantlets of Pérola and Smooth Cayenne cultivars were bacterized with AB213 and AB219, and had been cultivated during 140 days on vermicompost and vermiculite mixture. The plant colonization by diazotrophs was confirmed. Plantlets of Perolera cultivar grew better on substratum with carbonized rice hulls, vermiculite and vermicompost and obtained benefits from AB219 bacterium. All diazotrophs did not improve significantly the biomass of the Primavera cultivar. Increment on root dry matter of Pérola cultivar ranged from 23.1% to 38.5%, when AB213 and AB219 were applied, respectively. The AB213 isolate incremented 15.2% of dry matter in shoots of Smooth Cayenne cultivar. The results indicated the diazotrophic bacteria efficiency in promotion of pineapple plant growth.
Ananas comosus; organic wastes; growing media; plant propagation
