Text of Phyllosheric n fixation and factors affecting nodulation
PhyllosphereThePhyllosphereis a term used inmicrobiologyto refer to the total above-ground portions of plants as habitat formicroorganisms.
Divisions of Phyllosphere
Phyllospheric N fixationFixation of N on the surface of leaf.Leaf surface has been shown to provide appropriate conditions for colonization by microorganisms including diazotrophic bacteria that are able to fix atmospheric nitrogen N2.
Microbial Communities On Leaves
Different genera of bacteria, filamentous fungi, yeasts, algae, and, less frequently, protozoa and nematodes.
Filamentous fungi are present as sporesBacteria are the most abundant inhabitants of the phyllosphere.
N-fixation AssociationsLichens: cyanobacteria and fungiMosses and liverworts: some have associated cyanobacteriaAnabaena Azolla (Nostoc): cyanobacteria in stem of water fernGunerra Nostoc: cyanobacteria in nodule of dicot.
Acetobacter diazototrophicus lives in internal tissue of sugarcane and can fix 100-150 kg N/ha/year
A few legumes (Susbenia rostreta) have root nodules as well as stem nodules. Stem nodules are capable of photosynthesis and N-fixation.
Research on the characteristics of microbial life in the phyllosphere is of great commercial importance to the agricultural industry for two reasonsUnderstanding the survival of plant disease-causing bacteria and fungi is vital for developing new ways to control their spread.
There has been a recent rise in the number of food poisoning cases associated with fruit and vegetables contaminated with bacteria, such as Salmonella and E. coli.
Factors Affecting NodulationSoil chemistry and nutrientsAddition of nitrogenConcentration of inorganic nutrientsSoil temperatureLight and shadingRhizospheric microorganismsCO2concentration