Diversidade rizobiana de caupi em solos de diferentes classes e origens

Abstract

Caatinga has high plant diversity, including legumes which nodulate a large range of rhizobia. This work studied rhizobial diversity in three different classes of soil present in two municipalities of Pernambuco. Soil sampling was conducted in each soil class-municipality combination and the samples were used for inoculation in Leonard jars, with cowpea as bait crop. Harvest was 45 days later, and the nodules were used for rhizobial isolation and characterization. Morphological characterization was based on colony appearance speed, colony diameter, color, shape, elevation, border, transparency and surface, culture medium pH change, and mucus production, consistency and elasticity, followed by grouping at 100% similarity and authentication of group representative isolates. 479 isolates were obtained, and formed 100 and 175 100% similarity groups in Bom Jardim and Serra Talhada. Shannon and Weaver diversity indexes presented differences in the same soil class from the different municipalities. Besides soil classes, sampling municipalities also affected rhizobial population diversity.