Rizobacteria Isolated in the Amazon and Its Influence on the Growth of Guarana Seedlings

Abstract

Guarana (Paullinia cupana var. Sorbilis (Mart.) Ducke) is a species native from Amazon which has high caffeine concentration. The interactions between guarana and microorganisms in Amazonian soils need to be investigated, especially in relation to the seedling production process, due to its beneficial relationships such as biosynthesis and the supply of stimulating substances, which may result in shortening of the nursery garden or increased productivity. Thus, this research had the objective of evaluating the potential of growth caused by rhizobacteria (Burkholderia ambifaria and Bacillus sp.) in rooting of guarana seedlings. The root length, volume, dry matter of the aerial part, height, number of leaves, leaf area and dry matter of shoot were evaluated at 180 days after planting emergence. Were also determined the carbohydrate and proline content of the aerial part. The rhizobacteria did not influence the growth of the seedlings, however, the carbohydrate contents were higher when the inoculation of the rhizobacteria was carried out with the Burkholderia ambifaria bacteria in the cultivar BRS-Amazonas, with the best results. The proline levels were higher in the control treatment of the two cultivars.