Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 22
How has the use of Agrobacterium as vectors helped in controlling Meloidegyne incognitia infestation is tobacco plants? Explain in correct sequence.
Answer
RNA interferance is the cellular defense mechnism to prevent the infection Meloidegyne incognitia into tobacco plant. In this process Agrobacterium is used as vector nematode specific gene were introduced into the host plant. The DNA introduced will produce both sense and antisense RNA in the host cell. These two strands are complementry and form double stranded RNA. This double stranded RNA than initiate RNA interference. Due to this the mRNA of nematode get silienced and the parasete cannot survive in the transgenic host. Therefore the plant itself protected by parasite.
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