Biocontrol_lecture - Biological Control of Plant Pathogens...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Biological Control of Plant Pathogens
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Notes for control of pathogens with biological control. Total or partial destruction of pathogen populations by other organisms Suppressive soil – contains micro-organisms that are antagonistic to pathogens and limits build of pathogenic species and/or strains Avirulent strains of same pathogen Produce antibiotics Direct parasitism utilizing lytic enzymes Indirect toxic effects through release of volatile subsstances such as ethylene (metabolic release) Competition for food Pre-occupation of penetration sites on hosts Mycoparasitism Opposite is conducive soils Examples of antagonistic micro-organisms include the fungal species Trichoderma, Gliocladium, Penicillium and bacterial Pseudomonas, Bacillus and Streptomyces Mostly a soil phenomenon but can occur in aerial environments also. Cross protection; plant tissues are protected from virulent strains of a virus through the presence of a less virulent stain. Plants can release toxins directly into soil. Some plants can trap and sequester pathogens Aphids carrying viruses can be “rinsed out” by planting border crops. Currently in use for reducing PVY in potatoes by planting soy beans around crop. Antagonistic plants. Release substances that are antagonistic to several plant parasitic nematodes.
Background image of page 2
What are Biopesticides? Biopesticides (also known as biological pesticides) are certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals. Favored in organic and minimal environment impact systems (and by EPA) Contain a microorganism (bacterium, fungus, virus, protozoan or alga) as the active ingredient. Bacterium Bacillus subtilis , B. pumulis  produce lipopeptides Certain other microbial pesticides act by out-competing pest organisms. Pesticidal substances that plants produce from genetic material that has been added to the plant. the gene for the Bt pesticidal protein, and introduce the gene into the plants own genetic material. Then the plant instead of the Bt bacterium--manufactures the substance that destroys the pest. Both the protein and its genetic material are regulated by EPA; the plant itself is
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 12

Biocontrol_lecture - Biological Control of Plant Pathogens...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online