Q.What process is involved for the prevention of nematode infestation in the roots of tobacco plant? Briefly explain.

Tobacco plants engineered to produce dsRNA against a nematode gene trigger RNA interference in the feeding nematode, silencing its gene and preventing root infestation.

Prevention of nematode infestation in tobacco: The specific nematode Meloidogyne incognita infests the roots of tobacco plants, causing significant reduction in yield. Scientists developed nematode resistance using the process of RNA interference (RNAi), a method that employs highly specific gene silencing.

Process: A specific gene from the nematode was identified and introduced into the tobacco plant's genome (using Agrobacterium as a vector), engineered in such a way that the transgenic plant produces both a sense RNA and a complementary anti-sense RNA for that particular nematode gene, within the plant's own root cells. Because these two RNA strands are complementary to each other, they hybridise/anneal to form a double-stranded RNA (dsRNA), which initiates the RNA interference pathway — this dsRNA is a signal that is bound and processed by the cell's silencing machinery. When the nematode subsequently infects (feeds on) the transgenic root, its own mRNA (the transcript of that specific gene, essent …