Abstract Rising concentrations of carbon dioxide (CO 2 ) is likely to have important effects on growth and development plants their relationship with symbiotic microbes. A rise in CO could increase demand by plant hosts for nutrient resources, which may host investments beneficial symbionts. In the legume-rhizobia mutualism, while elevated often associated increased nodule investment N -fixing ...

An in vitro study was conducted to determine the effects of the superior indole-3-acetic acid (IAA) producing Rhizobia and treatments of Ag and Ltryptophan (Trp) on wheat growth indices. Nine strains with different ability of IAA production (belonging to genus Rhizobium leguminosarum var. phaseoli and Rhizobium leguminosarum var. viciae, Sinorhizobium meliloti) and a non-inoculated control; two...

Plant NADPH oxidases, formerly known as respiratory burst oxidase homologues (RBOHs), are plasma membrane enzymes dedicated to reactive oxygen species (ROS) production. These oxidases are implicated in a wide variety of processes, ranging from tissue and organ growth and development to signaling pathways in response to abiotic and biotic stimuli. Research on the roles of RBOHs in the plant's re...

In nitrogen-fixing symbiosis, plant sanctions against ineffective bacteria have been demonstrated in previous studies performed on soybean and yellow bush lupin, both developing determinate nodules with Bradyrhizobium sp. strains. In this study, we focused on the widely studied symbiotic association Medicago truncatula-Sinorhizobium meliloti, which forms indeterminate nodules. Using two strains...

The anatomy and ultrastructure of root nodules of Anadenanthera peregrina var. falcata (Leguminosae-Mimosoideae) were analysed, as was plant growth. To ensure that nodules developed, seedlings were inoculated with a mixture of six strains of rhizobia. Nodules were produced that differed in appearance-and probably also effectiveness-but their structure was similar and they showed characteristics...

The effect of a variety factors on the survival of several rhizobia strains on inoculants and inoculated seeds has been evaluated. Since the rhizobia strains showed different cell-density-evolution patterns on peat-based inoculants and on inoculated seeds, several inoculant formulations with highly effective Rhizobium/Bradyrhizobium strains (for Lupinus, Hedysarum, Phaseolus and Glycine max.) w...

Understanding how mutualisms evolve in response to a changing environment will be critical for predicting the long-term impacts of global changes, such as increased nitrogen (N) deposition. Bacterial mutualists in particular might evolve quickly, thanks to short generation times and the potential for independent evolution of plasmids through recombination and/or horizontal gene transfer (HGT). ...

Compatible rhizobia strains are essential for nodulation and biological nitrogen fixation (BNF) of hairy vetch (Vicia villosa Roth, HV). We evaluated how past HV cultivation affected nodulation and BNF across host genotypes. Five groups of similar HV genotypes were inoculated with soil dilutions from six paired fields, three with 10-year HV cultivation history (HV+) and three with no history (H...

Low levels of phosphorus and high levels of aluminum are important soil acidity factors for the growth of higher plants; however, very little is known about their effects on the soil rhizobia. The present study was conducted to determine the relative effects of acidity, P, and Al on rhizobia. Tolerance of low pH (4.5), low P (510 μM), and high AI (50 μM) was assessed for 10 strains of cowpea rh...