Bacillus Thuringiensis (BT)

Caterpillars, Beetles, Flies and fly larvae - such as whitefly, cabbage moth and cabbage fly, carrot fly (521)

Colorado beetle (496)

A small potato plot (15 m2) was badly affected by the Colorado potato beetle. On June 22 the first half of the field was sprayed in the morning with Bacillus thuringiensis 6 D from Homeoplant (dosage: 10 ml in 10 liters of water). On June 23 the treatment was repeated on the second half of the field. After 1 day, the small and medium-sized larvae ceased feeding, turning their heads up; the large larvae continued feeding but noticeably more slowly. The small larvae then died but the medium and large larvae recovered and continued feeding. A further application of the remedy had no apparent additional effect. (496)

Bt for pest control looked at first to be very promising. It appeared to kill serious pests ... while being non-toxic to humans, spiders and other predators. By transferring the genes and encoding these in crop plants it was assumed that the plants themselves would be the insecticides .... Bt has the disadvantage that ... while this may work the first few times, after a period the pest begins to develop resistance ... Bt in potency has none of the disadvantages of its crude form ... (521)