Question

For producing disease and pest-resistant plants, which of the following methods are recommended?

• A. Genetic engineering with genes like Bt-toxin gene
• B. Hybridisation with resistant wild varities
• C. Gene therapy
• D. Both (a) and (b)

Answer 1

The correct option is D Both (a) and (b)

The production of pathogen-resistant transgenic plants has been achieved by inserting certain genes into the plant's genome that confer resistance to such pathogens as viruses, fungi, and insects. For example, the gene for Bt-toxin from the bacterium Bacillus thuringiensis. It kills insects of certain orders such as lepidopterans, coleopterans, and dipterans by binding to their midgut epithelium cell surface and creating pores causing the death of the insects. Introducting the Bt gene into plants makes them resistant to insects as the cells of the plant would then synthesise this toxin.

Plant hybridization is the process of crossbreeding genetically dissimilar parents to produce a hybrid. Natural resistance against pests and microbial pathogens exists in many wild vaities of the cultivated plants. Crossbreeding of high yielding cultivated varities with naturally resistant varities can produce a hybrid with disease or pest resistance features combined with high yielding capacity.

Thus, both genetic engineering and hybridisation with wild resistant varieties are techniques used for producing disease and pest-resistant plants.

Gene therapy is a technique that modifies a person's genes to treat or cure disease. Gene therapies can work by several mechanisms: Replacing a disease-causing gene with a healthy copy of the gene. Inactivating a disease-causing gene that is not functioning properly.