Some successful microbial pesticides

a. Bacillus thuringiensis (Endotoxin)

• Both sporulating and non-sporulating bacteria are considered potential candidates for development bacterial pesticides.
• More success in spore forming Bacillus (B. thuringiensis, B. popilliae, B. lentimorbis and B. moritai), nearly ½ of all trade named microbial products.
• The toxicity of Bt strains is attributed to glycoprotein, protoxin, generally called as endotoxin, that is produced during sporulation/fermentation.
• It is a crystalline product and when a larva ingest the spore, Bt toxin is activated in mid-gut causing distortion and eventual brusting of epithelial cells.

b. Agrobacterium radiobacter (Agrocin)

• Crown gall (tumour) in peaches, grapevine, roses and other various plants caused by soil-borne pathogen Agrobacterium tumefaciens.
• But an efficient BCA related to non-pathogenic A. rdiobacter, to treat roots during transplanting checks crown gall.
• Effective strains of A. radiobacter possesses two important features;

✓ They are able to colonize host roots to a higher population density.

✓ They produce an antibiotic, agrocin, that is toxic to A. tumefaciens.

✓ Agrocin is a rogue nucleotide encoded by plasmid of A. radiobacter that interfers with DNA synthesis in A. tumefaciens, however, it also carries genes for insensitivity to toxin.

c. Pseudomonas fluorescens (Phenazine)

• On the basis of the tests to grow quickly in the rhizosphere, it is released as BCA.
• To control damping-off caused by Pythium sp, Rhizoctonia solani, Gaeumannomyces graminis (in cereals).

d. Trichoderma

• Used against Necteia galligena, that cause silver-leaf disease of fruit trees by entering through pruning wounds.

e. Metarizium anisopliae (green muscardine fungus)

• Best known entomopathogenic fungi.
• Infect a wide range of insects; grasshopper, locust, spittlebugs, rhinoceros beetles).

f. Beaveria bassiana (white muscardine fungus)

• To control Colorado potato beetle, bark beetles.

g. Verticillum lecanii: for aphids and whiteflies

h. Nomuraea riley: for soybean caterpillars

I. Viruses

• Virus are strong regulators of insect population.