The process of RNA interference (RNAi) was used in Tobacco plant to develop resistance against:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Nematodes
Option (1) Viruses — Incorrect. NCERT's RNAi example in tobacco is against a worm, not a virus.
Option (2) Fungi — Incorrect. NCERT’s RNAi example in tobacco is against the nematode Meloidegyne incognitia, which infects the roots. No fungus is involved.
Option (3) Nematodes — Correct. The nematode Meloidegyne incognitia infects the roots; the plant's dsRNA silences a gene of the parasite, which then cannot survive.
Option (4) Insects — Incorrect. Insect pests are controlled with Bt toxin, not with RNAi.
NCERT Extract:
Biotechnological Applications in Agriculture – “… Pest Resistant Plants: Several nematodes parasitise a wide variety of plants and animals including human beings. A nematode Meloidegyne incognitia infects the roots of tobacco plants and causes a great reduction in yield. A novel strategy was adopted to prevent this infestation which was based on the process of RNA interference (RNAi).”