History of Bt
What is Bt
how does Bt work
Bt Animal safety
What is a Bt crystal
Genetically Modified Organisms
Bt Transgenic Crop
Bt cotton
Bt crop refuge
Synthetic Pesticide
Organic farming
Bt vector control
Pest resistance

Crop SprayingOrganic Farming:

Bt proteins has been used in many organic farms for over 50 years as a microbial pest control agent (MCPA). Bt proteins are allowed in organic farming as a insecticide because Bt is a natural, non-pathogenic bacterium that is found naturally in the soil. Bt has also been found to be safe to all higher animals tested.

Bt strains account for nearly 90% of the world MPCA market. Most of the Bt products contain insecticidal crystal proteins (ICP) and viable spores (spores that can produce live bacteria). The ICPs are responsible for insect toxicity. ICPs are usually biologically inactive within hours or days. A few products contain inactivated spores.

Typical agricultural formulations include wettable powders, spray concentrates, liquid concentrates, dusts, baits, and time release rings. Bt formulations may be applied to foliage, soil, water environments or food storage facilities. There are many different strains of Bt used, each specific to different insects. Because Bt is species specific, beneficial and non-target insects are usually not harmed.

Popular Bt Strains used

Bt Strain Effective against
Bt kurstaki (Btk) types of lepidopterous insects gypsy moth cabbage looper
Bt aizawai (Bta) wax moth larvae in honeycombs
Bt israelensis (Bti) mosquitoes, blackflies, midges
Bt san diego certain beetle species, bool weevil

Cotton BollwormBt is effective only when eaten by the insect as a larva, Bt is ineffective against most adult insects. Since Bt is applied topically, insects that attack the roots or the insides of a plant will not be affected.