There is evidence that plants produce certain ...

Elaine R. Ingham

Bacteria are tiny, single-celled organisms - generally 4/100, 000 inch wide (1 m)

and a little more in length. The fact that bacteria do not have in size, they make up in numbers.

Teaspoon of productive soil generally contains from 100 000 000

and 1 billion bacteria. It is so much mass of two cows per acre. Bacteria

divided into four functional groups. Most of them are redutsenty

, which consume simple carbon compounds such as root secretions and fresh plants

garbage. By this process, bacteria convert the energy in the soil organic matter in the form

useful to other organisms in the food soil. Number

destroyers can break pesticides and contaminants in strattera price soil. Decomposers are

especially important in the immobilization or retaining, nutrients in the cells

. thereby preventing loss of nutrients such as nitrogen from the rooting zone. >> << The second group of bacteria that mutualists partnerships with plants. The most famous of these is >> << nitrogen-fixing bacteria. The third group of bacterial pathogens of bacterial pathogens

Xymomonas include and Erwinia species and species

Agrobacterium, that cause halloobrazovaniyu in plants. The fourth group, called

lithotrophs hemoavtotrofy or receives energy from nitrogen compounds,

sulfur, iron and hydrogen instead of carbon compounds. Some of these species >> << are important to nitrogen cycling and degradation of pollutants. WHAT TO DO bacteria? Bacteria from all four groups

perform important services related to water dynamics, nutrient cycling and disease suppression

, . Some bacteria affect water movement by producing substances >> << that help bind soil particles into small aggregates (with diameters

1/10 ,000-1/100 inch or 2-200 microns). Stable aggregates improve water infiltration

and Water-retaining capacity of soil. In various bacterial community >> << Many organisms will compete with pathogenic organisms in the top

and aboveground surfaces of plants. Form

symbiotic association with roots of legumes like clover, lupine, and

trees such as alder and locust. Visible nodules are created where bacteria infect

growing root hair (see photo below). The plant supplies simple carbon compounds

for bacteria and the bacteria convert nitrogen (N2) from air in the form of factory

host can use. When the leaves or roots of the plant host decompose, soil nitrogen increases

around. Nitrite >> << bacteria change ammonium (NH4 +)

to nitrite (NO2-)

then nitrate (NO3-)

- best form of nitrogen for grasses and most cultivated crops. Nitrate leaching

easily from the soil, so some farmers use nitrification inhibitors

lower activity of one type nytryfytsyruyuschyh bacteria. Nitrite bacteria

suppressed in forest soils, so that most of nitrogen is ammonium >>. << Convert nitrates into nitrogen (N2) or

nitrous oxide (N2O) gas. Denitrifikatory is anaerobic, meaning they are active, where >> << oxygen is absent, for example, in saturated soils or inside soil aggregates. Actinomycetes is a large group of bacteria that grow as hyphae of fungi (see

photo below). They

responsible for the characteristic "earthy" smell of fresh turned

healthy soil. Actinomycetes to decompose wide range of substrates, but

particularly important in this, degrading recalcitrant (difficult to decompose) compounds

, such as chitin and cellulose, and active at high pH levels. Fungi are more important

in degrading these compounds at low pH. Number of antibiotics

producing actinomycetes such as Streptomyces. WHERE

bacteria? Different species of bacteria >> << develop different sources of power in different microhabitat >>. << General, bacteria are more competitive when labile

(easy to metabolism) substrates are present. This includes fresh, young plant

balance and compounds contained in the living roots. Bacteria in particular are concentrated in the

ryzosferi, a narrow region near and roots. There is evidence that plants produce certain types of root secretions for

stimulate the growth of protective bacteria. Bacteria alter the soil environment, provided that the soil >> << Wednesday will help some plant communities in comparison with others. Before plants

foothold in the fresh snow, bacterial community must establish first

from photosynthetic bacteria. These fix atmospheric nitrogen and carbon

produce organic matter and nitrogen immobilization enough and other nutrients >> << initiate the cycle of nitrogen in the soil of young people. Then, early >> << succession of plant species can grow. In the plant community found

, different types of organic materials are ground and change the type of food

available for bacteria. In turn, the altered bacterial community changes soil structure and

Environmental for plants. Some researchers believe it may be

can manage species at the site of soil bacteria

community. .