Nitrogen fixation and poly-β-hydroxybutyric acid content in bacteroids ofRhizobium lupini andRhizobium leguminosarum

Abstract

Experiments carried out in a sand culture have demonstrated that during the growth ofVicia faba andLupinus luteus inoculated with effective strains of Rhizobium, and when the behaviour of bacteroids isolated from nodules ofLupinus luteus, Pisum sativum andVicia faba which had been inoculated with effective and ineffective strains and when comparisons were made between bacteriods isolated from effective nodules ofVicia faba andLupinus luteus either at midday or at midnight there is a reverse correlation between the intensity of nitrogen fixation and respiration, on the one hand, and the content of poly-β-hydroxybutyric acid (PHB), on the other. This evidence suggests an important role played by PHB in the supply of symbiotic fixation with energy and carbon substrates.