Update on biological nitrogen fixation research on sugarcane in Guatemala

摘要

Field and laboratory studies were carried out to (i) quantify the contribution of biological nitrogen fixation (BNF) in several sugarcane varieties grown in Guatemala and (ii) to identify efficient methods of reproducing and inoculating Gluconacetobacter sp. Estimation of BNF contribution was made for 13 sugarcane varieties grown in pots containing 64 kg soil using the ~(15)N isotope-dilution method. The varieties SP79-2233 and PGM89-968 showed the highest BNF potential, being able to obtain 53 and 60% respectively of their nitrogen (N) uptake through BNF. Different liquid and solid culture media for growing Gluconacetobacter and four different methods of inoculation of Gluconacetobacter; either alone or in combination with Herbaspirillum sp., wereevaluated. Gluconacetobacter reproduced more efficiently in liquid growing media when compared with solid media. All four methods of inoculation were equally effective as indicated by a higher biomass production compared to the uninoculated control.