Unlike the major cereal crops corn, rice, and wheat, leguminous plants such as soybean and alfalfa can meet their nitrogen requirement via endosymbiotic associations with soil bacteria. The establishment of this symbiosis is a complex process playing out over several weeks and is facilitated by the exchange of chemical signals between these partners from different kingdoms. Several plant compon...

Improvements in understanding how climate change may influence chemical and physical processes in soils, how this may affect nutrient availability, and how plants may respond to changed availability of nutrients will influence crop breeding programmes. The effects of increased atmospheric CO2 and warmer temperatures, both individually and combined, on soil microbial activity, including mycorrhi...

Leguminous crops, possessing root nodules, fix and utilize atmospheric nitrogen. They are thus not dependent on industrially fixed nitrogen but add up to 30 kg of nitrogen / hectare to the soil and improve its fertility. Access to mineral nitrogen often limits plant growth, and so symbiotic relationships have evolved between plants and a variety of nitrogen-fixing organisms. These associations ...

We report here the existence of anaerobic nitrogen-fixing consortia (ANFICOs) consisting of N(2)-fixing clostridia and diverse nondiazotrophic bacteria in nonleguminous plants; we found these ANFICOs while attempting to overcome a problem with culturing nitrogen-fixing microbes from various gramineous plants. A major feature of ANFICOs is that N(2) fixation by the anaerobic clostridia is suppor...

The availability of nitrogen is one of the major limiting factors to crop growth. In the developed world, farmers use unsustainable levels of inorganic fertilisers to promote crop production. In contrast, in the developing world inorganic fertilisers are often not available and small-holder farmers suffer the resultant poor yields. Finding alternatives to inorganic fertilisers is critical for s...

The genus Burkholderia comprises 19 species, including Burkholderia vietnamiensis which is the only known N(2)-fixing species of this bacterial genus. The first isolates of B. vietnamiensis were recovered from the rhizosphere of rice plants grown in a phytotron, but its existence in natural environments and its geographic distribution were not reported. In the present study, most N(2)-fixing is...

Rhododendron aureum Georgi is a perennial evergreen dwarf shrub that grows at all elevations within the alpine tundra of northern China. Previous research has investigated the plant communities of R. aureum; however, little information is available regarding interspecific competition and underground soil microbial community composition. The objective of our study was to determine whether the pr...

In field trials conducted at four sites in Hawaii, soybean (Glycine max) and bush bean (Phaseolus vulgaris) were either inoculated with homologous rhizobia, fertilized at high rates with urea, or left unamended. Crop phenology was assessed every few days. Rates of biomass and N accumulation and components of yield were measured five times during each crop cycle to assess the extent to which: (i...

It is a common misconception that game-based learning is, by its very nature, engaging for the majority of learners. This is not necessarily the case, particularly for learners in Higher Education who may need to be persuaded of the value of learning games. For some learners, games may simply not be perceived as engaging–either in terms of an initial motivation to play or sustained participatio...

Multistrata agroforestry systems with tree crops comprise a variety of land use systems ranging from plantations of coffee, cacao or tea with shade trees to highly diversified homegardens and multi-storey tree gardens. Research on plant-soil interactions has concentrated on the former. Tree crop-based land use systems are more efficient in maintaining soil fertility than annual cropping systems...