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Why Azospirillum brasilense is gram negative?

Why Azospirillum brasilense is gram negative?

Azospirillum brasilense is a Gram-negative, nitrogen-fixing bacterium that colonizes the rhizosphere of various grasses and cereals. This strain has one of the largest genomes in the phylum Proteobacteria. The genome size is 7,530,241 bp, which is one of the largest genomes among bacterial species.

What are the characteristic features of Azospirillum?

Characteristics. The genus Azospirillum belongs in the alpha-Proteobacteria class of bacteria. Azospirillum are gram-negative, do not form spores, and have a slightly-twisted oblong-rod shape. Azospirillum have at least one flagellum and sometimes multiple flagella, which they use to move rapidly.

How do you identify Azospirillum?

Under light microscope, they were gram negative, plump rods ranged from 3- 5 µm size and showed fast helically motility which confirmed their identification as Azospirillum sp. Azospirillum spp. are reported to stimulates plant growth by production of phytohormones.

How do you use Azospirillum Biofertilizer?

Azospirillum is used for seedling root dip particularly for rice. 4 kg each of the recommended biofertilizers are mixed in 200 kg of compost and kept overnight. This mixture is incorporated in the soil at the time of sowing or planting. The inoculum should be applied 2-3 cm below the soil at the time of sowing.

What do you mean by Diazotrophs?

Diazotrophs are microorganisms that fix atmospheric nitrogen gas into a usable form by plants such as ammonia.

Is Azospirillum a Biofertilizer?

3. Azospirillum spp. Azospirillum species were considered as nitrogen fixers that made them to be used as biofertilizers (Bashan and Levanony, 1990; Bashan and Holguin, 1997; Pereg Gerk et al., 2000; El-Komy, 2005; Bashan et al., 2004).

Which media is used for isolation of Azospirillum?

For the isolation of Azospirillum spp., Nfb semisolid medium was used.

What is Biofertilizer PPT?

INTRODUTION A biofertilizer is a substance which contains living microorganisms, when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant.

Is mycorrhiza a biofertilizer?

Mycorrhizae are obligate fungi that predominate in the roots and soil of higher plants. They also increase the resistance in plants against plant pathogens and surface area of root system for better absorption of nutrient from soil. Therefore, they can be used as biofertilizer and as biocontrol agent.

Why should we use biofertilizer?

Biofertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorus, and stimulating plant growth through the synthesis of growth-promoting substances. Through the use of biofertilizers, healthy plants can be grown, while enhancing the sustainability and the health of the soil.

Why do diazotrophs fix nitrogen?

Diazotrophs are bacteria and archaea that fix atmospheric nitrogen gas into a more usable form such as ammonia. A diazotroph is a microorganism that is able to grow without external sources of fixed nitrogen. Examples of organisms that do this are rhizobia and Frankia (in symbiosis) and Azospirillum.