BIOTECHNOLOGICAL APPLICATIONS IN AGRICULTURE By HARIOM PATEL
Genetically Modified Organisms (GMO) e Plants, bacteria, fungi and animals whose genes have been altered by manipulation
(1) made crops more tolerant to abiotic stresses (cold, drought, salt, heat) (ii) reduced reliance on chemical pesticides (pest resistant crops) (ii) helped to reduce post harvest losses. (iv) increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil (v) enhanced nutritional value of food, e.g. Vitamin A enriched rice Advantages
Bt Cotton Not Biotech cotton but Bacillus thuringiensis e Produces proteins that kill certain insects such as lepidopterans (tobacco budworm, armyworm), coleopterans (beetles) and dipterans (flies, mosquitoes). B. thuringiensis forms protein crystals (inactive protoxins) during a particular phase of their growth. These crystals contain a toxic insecticidal protein e It is converted into an active for of toxin due to the alkaline pH of the gut whiclh solubilise the crystals. r h of the nsect
Please rattafy The toxin is coded by a gene named cry. There are a number of them, for example, the proteins encoded by the genes cryLAc and cryILAb control the cotton bollworms, that of cryLAb controls corn borer.
Pest Resistant Plants(RNAi) * A nematode Meloidegyne incognitia infects the roots of tobacco plants and causes a great reduction in yield RN Ai takes place in all eukaryotic organisms as a method of cellular defense that binds to and prevents translation of the mRNA (silencing) viruses having RNA genomes or mobile genetic elements (transposons) that e Silencing of a specific mRNA due to a complementary dsRNA molecule e The source of this complementary RNA could be from an infection by replicate via an RNA intermediate
The introduction of DNA was such that it produced both sense and anti- sense RNA in the host cells. These two RNA's being complementary to each other formed a double stranded (dsRNA) that initiated RNAi and thus, silenced the specific mRNA of the nematode.