What do you understand by the term bio pesticide? Name and explain the mode of action of a popular bio pesticide.

Dear Student
Bio pesticides are substances derived from natural sources such as animal , plants , microbes etc. These substances are intended to control pests and weeds.
BT toxins crystals are microbial derived insecticidal protein which activates in the gut of insect after lepidopteran insect pest ingest it. It leads to cell integration and insect death.

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