Disease management methods Lecture 13

Disease management methods Lecture 13

1. Terminology

   • It is to describe the varieties of a plant species on which the pathogen cannot cause the disease.
   • Susceptible - Plant under conditions suitable for the infection and the disease development. Tolerance – Plant of a disease without dying of suffering serious injury or crop loss
   • Avirulence – A certain plant of variety that can be carries of genetic resistance. Virulent – It being capable of pathogen that strongly pathogenic

2. Resistance in Host Plants

   • Host reaction - The number of genes are being determining by the resistance are from plant to plant. The number of genes are determining virulence and avirulence varies are from pathogen to pathogen
   • In the pathogen, genes of avirulence are usually dominant (A) and genes for virulence are recessive (a)

3. Types Of Plant Resistance

   • Basal resistance
     • It can be triggered when plant cells recognize microbeassociated molecular patterns.
   • Hypersensitive response (HR)
     • ➢The HR is deliberate plant cell at the site of infection. The HR may limit pathogen access to water and nutrients by sacrificing a few cells in order to save the rest of the plant.

4. Molecular and biotechnology

   • Biotechnology
     • Technology occupied on the biology. Integration of other fields such as biochemistry and chemical engineering.
   • Plant tissue culture
     • ➢The propagate plants are being under sterile conditions.

5. Enhancing plant resistance

   • Genes from the Plant Kingdom - The resistance are being identified
     • Phytoalexins
       • Tobacco – The production reduces the number of plant get infected by Botrytis cinerea
     • lytic peptides
       • Cecropins – antibacterial lytic peptides from giant silk moth
       • Tobacco expressing cecropins – increased resistance to Psedomonas syringae