Mutualisms are key determinants of community assembly and composition, but urbanization can alter the dynamics these interactions associated effects on ecosystem functions. Legume–rhizobia mutualisms a model interaction to evaluate ecological ecosystem-level urbanization, particularly urban-driven eutrophication nitrogen (N) deposition. Here, we evaluated how affected ecology mutualism between ...

Abstract Background For well over a century, rhizobia have been recognized as effective biofertilizer options for legume crops. This has led to the widespread use of rhizobial inoculants in agricultural systems, but recurring issue emerged: applied struggle provide growth benefits largely attributed presence soil and termed ‘rhizobial competition problem.’ Scope Microbiome engineering emerged m...

Nothing is more important for effective nodulation of legumes that the availability of sufficient numbers of an infective strain of rhizobia in the root zone of seedlings. In some cases, the soil will contain sufficient numbers of infective rhizobia but modern approaches to the use of genetically superior strains of rhizobia practically demands the use of some means of inoculation, thus raising...

The interaction between legumes and rhizobia has been well studied in the context of a mutualistic, nitrogen-fixing symbiosis. The fitness of legumes, including important agricultural crops, is enhanced by the plants' ability to develop symbiotic associations with certain soil bacteria that fix atmospheric nitrogen into a utilizable form, namely, ammonia, via a chemical reaction that only bacte...

Preferential rewarding of more beneficial partners may stabilize mutualisms against the invasion of less beneficial, that is cheater, genotypes. Recent evidence suggests that both partner choice and sanctioning may play roles in preventing the invasion of less-beneficial rhizobia in legume-rhizobium mutualisms. The importance of these mechanisms in natural communities, however, remains unclear....

Nitrogen-fixing symbioses between legumes and bacteria of the family Rhizobiaceae involve differentiation of both plant and bacterial cells. Differentiation of plant root cells is required to build an organ, the nodule, which can feed and accommodate a large population of bacteria under conditions conducive to nitrogen fixation. An efficient vascular system is built to connect the nodule to the...

Over the last several decades, there have been a large number of studies done on the genetics, biochemistry, physiology, ecology, and agronomics of the bacteria forming nitrogen-fixing symbioses with legumes. These bacteria, collectively referred to as the rhizobia, are taxonomically and physiologically diverse members of the a and b subclasses of the Proteobacteria, and mostly comprise members...

The organisms of the phytomicrobiome use signal compounds to regulate aspects of each other's behavior. Legumes use signals (flavonoids) to regulate rhizobial nod gene expression during establishment of the legume-rhizobia N2-fixation symbiosis. Lipochitooligosaccharides (LCOs) produced by rhizobia act as return signals to the host plant and are recognized by specific lysine motif receptor like...

The increase in human population and the spread of agriculture over the past 150 years have transformed the landscape in west-central Minnesota into a mosaic of agricultural fields and urban land, leaving only remnants of the once dominant prairie ecosystem. Limited natural habitat in this fragmented landscape threatens the diversity and abundance of native legumes and could impact the size and...

The symbiotic association between certain plants and microorganisms plays an important role in soil fertilization, and improves their growth and mineral nutrition. Microorganisms implicated in this symbiotic interaction are from two groups: bacteria and fungi. The bacteria group is implicated on nitrogen fixation (for review see Pawlowski and Bisseling, 1996), while the fungal group is involved...