Question

Considering what we know about the various ways to classify bacteria based on temperature (e.g. psychrophiles, mesophiles, etc.), how would you classify the following species? Explain your rationale for each. a. Benthic zones at the bottom of oceans b.Microorganisms that are abundant in the upper atmosphere, particularly downwind of arid regions where winds can mobilize large amounts of topsoil and dust. Airborne cells can spread genes to distant environments and even influence weather as cloud/ice condensation nuclei. c. The term 'rizosphere' was coined by Hiltner in 1904 to describe the portion of soil where microorganism-mediated processes are under the influence of the root system. Functions of the rizoshpere are of central importance for plant nutrition, health and quality.

Answer 1

A. Benthic zones has wide zone of organism such as crustaceans, sponges, bivalaves, snails, seastars, polychaetes and fishes. Because of close of proximity of water surface temperature at benthic zone vary from warmer to shallow depths and may drop to 2-3 degree c. At such low temperatures quality of life of organism may be affected and they move to much warmer conditions where they get more energy and can host there complex systems.

B. The organisms in arid regions are Proteobactria , Actinobacteria and Firmicutes.These organisms were analysed using 16srRNA genes. The study regarding this was conducted with ALRT plumes. Airbone organism contribute to cloud formation and the concentration of microbial cell in the lower troposphere. These pathogens promote hetrogeneous freezing of ice through the action an out membrane protien known as inaZ protien which serves as nucleation center. These protiens can damage leaves and facilitate plant infections and can act as efficient ice nuclei at temperatures as high as -2 degree c.  

C. The rhizosphere is part of soil surrounding the plant roots. The exudates released from roots make it a site of complex biochemical activity. Microorganisms in the dynamic parts of rhizosphere affect the soil and plant growth i.e biological imbalance and resourse limitation.The disturbance are created by polluting soil and water, putting toxic agrochemicals and developing resistant to the pests.The rhizophere microflora enhances the quality of the soil. The common pathogen seen are Rhitezoctonia solani, B.cinere, aphanomyces, cochlioides, Pythium spp.and Erwinia amylovora.