Plant Disease

Plant Diseases

  • Blight - A general term used to describe the rapid and general killing of leaves, flowers or stems. Example: fire blight of pear.
  • Canker - A dead area on a stem surrounded by living tissue. Example: the fire blight bacterium produces cankers on limbs.
  • Chlorosis - Yellowing of normally green tissue due to partial failure of chlorophyll to develop.
  • Damping-off - A disease of seedling plants that kills individual plants; usually caused by fungi.
  • Dieback - Progressive death of branches shoots and roots beginning at the tips. Dieback may occur on roses after repeated defoliation by the black spot fungus.
  • Gall - A pronounced localized swelling on roots, stems or branches. Root knot nematodes cause root galling on susceptible plants.
  • Lesion - A localized spot of diseased tissue. Sunken lesions are caused by the bacterial spot organism on peach fruit.
  • Mildew - Whitish or grayish coating of fungal strands and spores appearing on a leaf surface infected by the powdery mildew fungus or the downy mildew fungus.
  • Mosiac - Alternate light and dark green areas occurring in leaves. Viruses such as tobacco mosaic cause mosaic patterns in leaves.
  • Rot - Decayed or decaying tissue caused by microorganism activity.
  • Stunting - Reduced plant size caused the action of pathogenic organisms.