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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Salvia > Discolored leaves

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Salvia > Leaves > Discolored leaves

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  • Aster yellows 1
  • Aster yellows 2
  • Aster yellows 3

Spider mites - Two-spotted spider mite
Tetranychus urticae

  • Active during summer, particularly abundant during hot, dry weather
  • Pale stippling appears on the upper leaf surface
  • Leaves are discolored off green to whitish, yellowish, or bronze
  • Premature leaf drop can occur
  • Visible webbing occurs on infected leaves when populations are high
  • Adults are tiny (1/50th inch long) and oval, greenish or yellowish with a dark spot on either side of the body
  • More information on Spider mites
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  • Image: gray mold 3
  • Image: gray mold 2
  • Image: gray mold 1

Root rot
Rhizoctonia solani and Pythium spp.

  • Leaves turn yellow and wilt
  • Plants are stunted
  • The base of the stem may turn brown and crack
  • Roots have brown sunken areas and lack root hairs
  • The outer root tissue may be easily removed leaving behind thin, stringy root cores
  • Disease common in cool, wet soil with poor drainage
  • Lab test necessary to distinguish between Rhizoctonia and Pythium Root Rot
  • More information on Pythium root rot
  • More information on Rhizoctonia root rot
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  • Image: gray mold 3
  • Image: gray mold 2
  • Image: gray mold 1

White Mold
Sclerotinia sclerotiorum

  • Entire plant or single branch wilts, leaves turn brown and die
  • Wilted stems are discolored, tan to off-white
  • Fluffy, white cotton-like fungal growth may been seen on infected plants when humidity is high
  • Round to irregular hard black fungal structures ranging in size from 1/16 to ½ inch can be found clinging to the outside an infected stem or embedded inside the dead stem
  • More information on white mold
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  • Tobacco mosaic virus 1
  • Tobacco mosaic virus 2
  • Tobacco mosaic virus 3

Gray Mold
Botrytis cinerea

  • Irregular brown spots on leaves
  • Brown blossoms or petals; flowers drop off prematurely
  • Gray fuzzy mold develops on rotted tissue under humid conditions
  • Disease develops during cool, wet weather
  • More information on Gray mold
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  • Tobacco mosaic virus 1
  • Tobacco mosaic virus 2
  • Tobacco mosaic virus 3

Powdery Mildew
Golovinomyces (syn. Erysiphe) spp.

  • Powdery, fluffy white spots and blotches on leaves, stems, and flower parts
  • Tiny black round spheres may be visible within white spots late in the season
  • Spots typically start on lower leaves but can spread to cover the entire plant
  • Severely infected leaves may be completely covered in white or grayish white fungi
  • In some cases, leaves become curled or twisted or turn yellow due to the infection
  • More information on Powdery mildew
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  • Snapdragon rust 1
  • Snapdragon rust 2
  • Snapdragon rust 3

Downy Mildew
Pernospora lamii

  • Plants become yellow in color and stunted
  • Large brown angular blotches may appear on leaves
  • Leaves may curl slightly downward
  • Grayish brown to purplish fungal growth can be found on underside of leaves in humid conditions
  • Infected leaves prematurely drop from the plant leaving a barren stalk with few leaves
  • Cool, wet weather favors disease
  • More information on Downey mildew

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