Biotechnology in Agriculture
Bt crops, pest-resistant plants and RNA interference against nematodes. (Biology › Biotechnology and Its Applications, NEET UG syllabus.)
What is Biotechnology in Agriculture?
An insecticidal protein produced by the bacterium *Bacillus thuringiensis*, which is toxic to certain insect pests upon activation in their gut.
Key points
- Explain the mechanism of action of Bt toxins in insect pests.
- List examples of Bt crops and the pests they target.
- Describe the principle of RNA interference (RNAi).
- Explain how RNAi is used to develop pest-resistant plants, specifically against nematodes.
Common exam trap
Believing Bt toxin is active in the plant itself; it's a protoxin activated in the insect gut.
Definitions
- Term
Bt Toxin
- Meaning
An insecticidal protein produced by the bacterium *Bacillus thuringiensis*, which is toxic to certain insect pests upon activation in their gut.
- Term
Cry Genes
- Meaning
Genes present in *Bacillus thuringiensis* that encode for insecticidal crystal proteins (Cry proteins).
- Term
RNA Interference (RNAi)
- Meaning
A biological process in which RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules, often triggered by double-stranded RNA (dsRNA).
- Term
*Agrobacterium tumefaciens*
- Meaning
A soil bacterium commonly used as a natural genetic engineer to transfer desired genes into plant cells, forming the basis of many plant genetic engineering techniques.
- Term
*Meloidogyne incognita*
- Meaning
A species of root-knot nematode that is a major pest of many crops, including tobacco, causing significant yield losses.
Learning objectives
Explain the mechanism of action of Bt toxins in insect pests.
List examples of Bt crops and the pests they target.
Describe the principle of RNA interference (RNAi).
Explain how RNAi is used to develop pest-resistant plants, specifically against nematodes.
Identify the role of *Agrobacterium tumefaciens* in plant genetic engineering.
Prerequisites
Basic understanding of DNA, RNA, and protein synthesis.
Knowledge of gene expression and regulation.
Familiarity with genetic engineering principles (vectors, gene transfer).
Basic plant biology and pest-plant interactions.
Common mistakes
Believing Bt toxin is active in the plant itself; it's a protoxin activated in the insect gut.
Confusing the mechanism of action between Bt toxin and RNAi.
Not knowing the specific pests targeted by Bt cotton or RNAi-based resistance.
Misunderstanding the role of double-stranded RNA (dsRNA) in RNA interference.
Keywords
Biotechnology
Bt crops
Bacillus thuringiensis
Cry genes
RNA interference
Meloidogyne incognita
Pest resistance
Genetic engineering
Transgenic plants
GMO
Practice preview
RNA interference (RNAi) is a method of developing pest resistance in plants by silencing specific:…
easy
For developing pest resistance against the nematode Meloidogyne incognita in tobacco plants using RNA interference, the dsRNA is typically introduced into the plant using which vector?…
hard
In the context of RNA interference (RNAi) for pest resistance against nematodes, what is the correct sequence of events after the plant is engineered? 1. Nematode ingests dsRNA. 2. dsRNA silences specific mRNA in the n…
medium