Q27 of 30 Page 1

(a) Tobacco plants are damaged severely when infested with Meloidegyneincognitia. Name and explain the strategy that is adopted to stop this infestation.

(b) Name the vector used for introducing the nematode specific gene in tobacco plant.


a. The infestation of tobacco plants with Meloidegyneincognitia is prevented by a strategy which was based on RNA interference or RNAi or gene silencing.

It is a process in which,the nematode specific gene is introduced into host plant (using Agrobacterium). The introduction of DNA produces both sense and anti-sense RNA in the host cells. These two RNAs being complementary to each other formed dsRNA. This specific mRNA of the nematode silenced and parasite dies.


b. Agrobacterium tumefaciens is the vector used for introducing the nematode specific gene in tobacco plant.


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