a. Pest Resistant Plants : Nematodes like Meloidegyne incognitia infects the roots of tobacco plants and causes reduction in yield. The infestation of htese nematodes can be prevented by the process of RNA interference.RNAi is present in all eukaryotic organisms as cellular defence by silencing of specific mRNA due to complementary dsRNA molecules that bind to and prevents translation of the mRNA.
The source of complementary dsRNA may be from an infection by viruses having RNA genomes or mobile genetic elements that replicate through RNA intermediate.
Nematode specific genes were introduces into host plant using Agrobacterium vectors. The parasite could not survive in a transgenic host expressing specific interfering RNA.