Plant doctor

When the leaves of some kinds of plants are bitted by insects, the substance A in the juice of plants will react with the one B in the spit of the insects. As a consequence, a volatile matter is produced, which attract the natural enemy of the insect. We plan to engineer the bacteria, having a symbiosis with plants, with genes of the enzymes which catalyze the production of the substance A in the juice. The bacteria will make plant doctors.