In nematode resistance by RNA interference, some specific genes were introduced which form dsRNA. These were introduced in

Options

A. Nematode
B. Host plant
C. Agrobacterium
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The question revolves around the use of RNA interference (RNAi) technology to develop nematode-resistant plants. RNA interference is a biological process where RNA molecules inhibit gene expression or translation, effectively silencing targeted genes.

2. **Role of dsRNA**: In this process, specific genes are introduced into the plant in the form of double-stranded RNA (dsRNA). This dsRNA is crucial because it can trigger the RNAi mechanism within the plant cells.

3. **Mechanism of Action**: When the dsRNA is present, it pairs with complementary mRNA molecules in the plant cells. This pairing leads to the formation of double-stranded RNA, which prevents the mRNA from being translated into proteins. Without these proteins, the nematodes cannot survive or reproduce effectively.

4. **Introduction of Genes**: To introduce the specific genes that produce the dsRNA, a common method used is the Agrobacterium-mediated transformation. Agrobacterium is a bacterium that can transfer genetic material into plant cells.

5. **Conclusion**: Therefore, the specific genes that form dsRNA are introduced into the plant using Agrobacterium vectors, which facilitate the genetic modification of the host plant to confer resistance against nematodes.

**Final Answer**: The specific genes forming dsRNA were introduced into the plant using Agrobacterium vectors.

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