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Key Words: Bacillus subtilis, Trichoderma viride, Lablab purpureus, Vigna radiata,

Capsicum annuum, Cicer arietinum, Bacteria, Fungi and pathogens.

INTRODUCTION:
Agriculture plays a major role in day to day life. Sustainable agriculture has been

developed to meet the needs of the society without industrial technologies. Though these
agricultural practices are followed the plants get easily affected by many external factors such

as bacteria, fungi, insects etc. Plant Growth Promoting Rhizobacteria (PGPR) are a certain

group of bacteria that colonizes the roots of plants. Bacterial diseases can be controlled by the
uses of these bacteria. Some of the plant growth promoting bacteria are Bacillus,

Pseudomonas, Erwinia, Azotobacter etc. PGPR fixes the atmospheric nitrogen and provide it

to the plants. Though the use of chemical fertilizers increases the crop production and faster
growth but it affects the soil fertility, pollutes the water and it is hazardous to the

environment. So, instead of these chemicals, biofertilizers like PGPR can be used. It doesn’t
cause any harm to the soil and it is environment friendly.

Bacillus subtilis is a gram-positive, rod shaped, aerobic bacteria that forms
endospores. These spores can survive in the soil for a longer period of time even in harsh

environmental conditions. It is a widely used rhizobacteria which promotes plant growth and

development. It has the capacity to secrete antibiotics. It activates biocontrol mechanism to
suppress the diseases which is caused by the pathogens. Trichoderma viride is a fungus and

acts as a biofungicide. It is mainly used to suppress the diseases which are caused by fungal
pathogens and also for the transformation of soil nutrients. This fungus grows best in the

acidic soil.
Leguminous crops itself can fix the nitrogen by the symbiotic bacteria which is

present in their root nodules. Cicer arietinum L. is a legume crop which is mainly cultivated

for its seeds. It belongs to the family Fabaceae. It reaches a height of about 20 – 60cm. It is
multipurpose grain legume and mainly used as a source of protein. Capsicum annuum L. is a

perennial plant and usually grown as an annual. It belongs to the Solanaceae family. It is a

short-lived plant and requires well drained soil. Lablab purpureus L. is a pulse crop and
belongs to the Fabaceae family. It is also a short-lived plant and reach upto 3-6m. Vigna

radiata L. is a legume crop which is cultivated for its edible seeds. It belongs to the family
Fabaceae. It acts as a good green manure.

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