Question
How have pest-resistant plants been produced using biotechnology? Explain.

Answer

Pest resistant plants:
  • A nematode Meloidegyne incognitia infects the roots of tobacco plants which reduces the production of tobacco.
  • It can be prevented by using RNA interference (RNAi) process which is checked by silencing of specific mRNA due to a complementary dsRNA.
  • dsRNA binds and prevents translation of the mRNA (silencing).
  • By using Agrobacterium vectors, nematode-specific genes were introduced into the host plants which produce both sense and anti-sense RNA in the host cells.
  • These two RNAs are complementary to each other and form a double-stranded RNA (dsRNA) that initiates RNAi and hence silence the specific mRNA of the nematode.
  • The parasite cannot survive in the transgenic host, so protects the plants from pests.

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