Abstract

The objective of this work was to determine the effect of a new Azotobacter-based biofertilizer on the development of plantain plantlets obtained by in vitro culture, during their acclimatization. Application were made weekly according to a completely randomized design (in 20x12cm polyethylene bags) with five treatments: 0 (absolute control), 1,2,3 and four applications of the biofertilizer. After one week of acclimatization, survival percentage was determined on the two commercial cultivars studied: ‘INIVIT PB-2012’ (ABB) and ‘INIVIT PV 06-30’ (AAB). Measurements were made in 20 randomly selected plantlets per treatment at 50 and 60 days after planting (dap): plant height, number of leaves, petiole length, width and length of the developed leaf and its leaf area was calculated. The survival plantlets at seven dap always behaved above 98 %. Evaluations at 60 dap, demonstrated that Azotobacter enhanced transplant vigor and stimulated the morphological development of both cultivars. A substantial increment of the size and health of surviving plantlets (height, longest and widest leaves) was determined, which were significantly different to the control (without biofertilizer). Plantlets inoculated with the new biofertilizer for three weeks were ready for transplanting, at least, nine days before to the control, and that has a favorable economic value.

Keywords: Biofertilizer; Biological nitrogen fixation; in vitro culture; Plant growth-promoting rhizobacteria; Sustainable agriculture