Growth promotion in Adesmia species by nodule rhizobacteria producing indolyl acetic acid

Abstract

The Adesmia species found in Rio Grande do Sul and Santa Catarina have high nutritional quality and may be used in breeding programs of native grasslands. The aim of this study was to evaluate the growth promotion in Adesmia species by rhizobacteria producing indolyl acetic acid (IAA). Seven isolates of bacteria from nodules of Adesmia latifolia
from the Epagri collection of rhizobacteria were used. These were analyzed for production of indolyl acetic acid and promotion of plant growth in A. latifolia, A. psoraleoides, A. riograndensis and A. tristis. The results showed a variable production of IAA by different isolates used. The isolates produced different effects in promoting the growth of different species of Adesmia. The bacterial strains used are specific for nodulation in A. latifolia. Leaf number and length of twoleaved shoots are not affected by the isolates used in this study. The effects of bacteria isolated from nodules in promoting growth varied depending on the interaction with the different species of Adesmia. EEL0710 strain promotes increased growth in A. latifolia, A. psoraleoides and A. tristis. EEL1710A strain promotes increased growth in A. riograndensis. The
level of endogenous IAA has no direct relationship in promoting the growth of Adesmia species.