Potencial de rizobactérias no crescimento de mudas de sibipiruna (caesalpinia peltophoroides BENTH)

摘要

The objective of this work was to evaluate the potential of growth-promoting rhizobacteria for seed germination and biomass of the root system and aerial part of seedlings of sibipiruna ( Caesalpinia Peltophoroides: ). Isolates pre-selected for eucalyptus were used, Ca, FL2, MF2, MF4, RC3, R1, 3918, S1, S2 and CIIB. Thus, samples of vermiculite-based substrate and carbonized rice hull (1:1) were treated with 5 mL of a suspension of each isolate (OD540= 0.2 A)/ tubette of 55 cc capacity corresponding to around 10 ufc/mL. The experimental design was completely randomized (CRD) with five repetitions per treatment, each constituted by 20 seeds. At 40 days, germination percentage and dry mass of the roots and the aerial parts were evaluated. A significant increase was observed in dry matter of the root and aerial part for all the rhizobacteria isolates tested, compared to the control. All the isolates provided significant germination increase, except 3918 and CIIB, which did not differ from the control. Among the tested isolates, four were the most promising (FL2, MF4, MF2 and CIIB). The results obtained show significant gains in seedling production, without any adjustment in nursery management or structure. In addition to this direct gain, it is possible to make a better use of the physical structure of the nurseries by reducing the time needed for seedling formation, reducing the production costs.