Advantages and Disadvantages

Advantages

    There are several advantages to using B. thuringiensis. Bt only kills harmful insects unlike many other insecticides.

It will not kill beneficial insects such as honeybees and other pollinators. A second advantage of Bt is that it's

not toxic to humans, wildlife, or pets. Because of this, it is used on many food crops and other sensitive crops where

pesticides might harm the consumer, or local wildlife.

 Disadvantages

    B. thuringiensis also has disadvantages. Many strains are susceptible to the sunlight and their potency will degrade

within a week. Some newer strains used on leaf beetles can become ineffective within 24 hours. Also, because Bt

insecticides are highly specific, many varieties must be used if you want to fully protect your crops. They just won't

be that effective on crops that have multiple pests. Because Bt insecticides are only useful when their are eaten,

sometimes they are ineffective because some insects such as codling moth don't get the chance to eat it.

    Also, many Bt insecticides have a shorter shelf life than other synthetic insecticides. Generally after two or three years their

efectiveness is reduced greatly. The optimal storage conditions for Bt products are cool, dry air and out of direct

sunlight.

Anthony M. Shelton/Biological Control: A Guide to Natural Enemies in North America