Recombinant DNA technology and classicial breeding.pptx

Recombinant DNA technology and classicial breeding

1. Triticum aestivum Modern bread variety Triticum monococcum Ancient variety How is a new plant variety created by classical breeding?

2. Classical Breeding

3. Random retention of information from each parent Classical Breeding

4. Yield Increase by year Classical Breeding

5. equivalent to a gene Inserts randomly in genome Genetic Engineering

6. Wild germplasm and internal borer management through classical breeding Very difficult! Why? Voracious eaters Feed is in gramme or milligramme quantities Damage to crop is enormous in space and time Quantum of toxin required to kill is in milligramme quantities Never available in wild germplasm But in exotic organisms like bacteria

7. Internal feeder (bollworm) Voracious eater Biting mouthparts Feed is in gramme or milligramme quantities Damage to crop is enormous in space and time Quantum of toxin required to kill is in milligramme quantities Bt toxins (gut-active) are an effective oral toxin Single egg to a single larva type reproduction

8. Sucking pests (aphid) Damage goes unnoticed Piercing and sucking mouthparts Specialized tissues fed upon Feed is in milligramme or in nanogramme quantities Quantum of toxin required to kill is in nanogramme quantities Bt toxins (gut-active) are not an effective oral toxin; a aphicidal toxin must to cross from the gut to hemocoel Parthenogenetic reproduction

9. Hv1a (spider-derived, peptide -hexatoxin-Hv1a; a neurotoxin) is aphicidal when injected into the aphid hemocoel but not when administered orally Transgenic arabidopsis expressing HV1a (carried from gut to hemocoel by a pea enation mosaic virus (a luteovirus ) coat protein.

10. Mode of action of Hv1a, an insect-specific neurotoxin