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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Fruit > Strawberry > Discolored or rotten fruit

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Strawberries > Fruit > Discolored or rotten fruit

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  • Image: Botrytis 1
  • Image: Botrytis 2

Gray Mold
Botrytis cinerea

  • Fruit develops indistinct, soft, light brown spots that rapidly enlarge and have a mild rotten smell
  • Gray powdery spores form on infected fruit under moist conditions
  • Disease favored by wet conditions and temperatures between 41-86F
  • One or several flowers in a cluster may turn brown to black and dry out
  • Black discoloration may extend down into the flower stalk
  • More information on Gray Mold
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  • Image: Sunscald/Heat Stress 1
  • Image: Sunscald/Heat Stress 2

Sunscald/Heat Stress

  • Berries are pink to bronze where directly exposed to sun
  • Berries have a pleasant, wine smell
  • Occurs in extreme heat at/near harvest
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  • Image: Flower Thrips 1
  • Image: Flower Thrips 2
  • Image: Yellow Nutsedge 2

Spotted Winged Drosophila
Drosophila Suzukii

  • Active in gardens from July to September
  • Larvae feed on healthy, intact, ripening fruits
  • Larvae feed within the berries causing brown, sunken areas
  • Fruit becomes soft and decays
  • Adult flies are small (1/8 - 1/12 inch) long, yellowish-brown and red eyes, larvae are small (1/8” long), white and cylindrical
  • More information on Spotted Winged Drosophila
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  • Image: Flower Thrips 1
  • Image: Flower Thrips 2

Flower Thrips
Frankliniella occidentalis

  • Feeding by thrips results in a berry that has a bronzed appearance
  • Thrips are very small insects (approximately 3/10 inch long) have feathery wings and vary in color from yellow to dark brown; nymphs are white or yellowish with small dark eyes
  • Thrips are present in early spring
  • More on flower thrips
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  • Image: Leather Rot 1
  • Image: Leather Rot 2

Leather Rot
Phytopthora cactorum

  • A section of the berry or the entire fruit may turn tan, purple or brown
  • Infected berries have a foul “chemical” odor and become tough, leathery
  • Berries with any amount of infection are very bitter tasting
  • Infects flowers, green fruit and ripe fruit
  • Commonly occurs in low areas or where free standing water is present
  • More information on Leather Rot
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  • Image: Anthracnose 2
  • Image: Anthracnose 3

Colletotrichum sp.

  • Fruit will develop distinct round sunken brown to black blotches with no smell
  • Wet pinkish orange sticky spores may form in the center of the fruit infection when wet
  • Fruit rot can occur on green or ripe fruit
  • Spots on leaves are small (<1/4"), round, sunken and gray-black, often resembling ink spots
  • Flower infection results in dried out and brown flowers and flower stalks
  • Occurs more frequently in very warm and humid weather (>80°F)
  • More information on Anthracnose
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  • Image: Leaf Blight 3
  • Image: Leaf Blight 2
  • Image: Leaf Blight 1

Leaf Blight
Phomopsis obscurans

  • First see purplish red round leaf spots with a gray brown center
  • Spots grow into a large V shaped lesion with a dry brown triangle in the center and a reddish purple V shaped border
  • Elongated, sunken, purplish brown or reddish brown spots or streaks may be seen on stems
  • Berries can develop soft pink-brown spots
  • More information on Leaf Blight

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