The objective of this work was to evaluate the effect of diazotrophic bacteria on yield of pineapple cv. Cayenne Champac (Champaka), under irrigation, with two levels of N fertilization. Treatments consisted of two N levels (180 kg and 300 kg ha-1 year-1), on the plots, and micropropagated plantlets inoculated with bacteria related to Burkholderia cepacia AB213, with Asaia bogorensis AB219 and without bacterial inoculation, on the subplots, using three replications. The bacterial inoculation was performed in a laboratory (with 10(8) bacterial cells plant-1) and the plant acclimatization in a glass house. After five months, they were transferred onto field, using 0.9 m between the lines and 0.3 m between the plants. The cultivar presented good performance under irrigation on the sandy soil in Pacajús, Ceará State, when fertilized with the highest N level. For each kilogram of the element the fresh mass of fruits grew by 124.3 kg ha-1, for the fertilizer levels. Plants inoculated with AB219 produced bigger fruits and 19.4% and 17.3% heavier when compared to fresh mass of fruits without and with crown from the controls on higher N level. The lower contribution of AB213 isolate was observed, and the fresh mass of fruits with crown ranged up to 9.9% on lower N level. The diazotrophic bacterial contribution on pineapple cv. Cayenne Champac was demonstrated with this work..
Ananas comosus L.; micropropagated plant; diazotrophic bacteria; Burkholderia sp.; Asaia bogorensis
