Carrot (Daucus carota)-Damping-off

Cause Mainly the fungus-like microorganism, Pythium spp., but also the fungi, Rhizoctonia sp. and Fusarium spp. These soilborne microorganisms are widespread and attack young and germinating seedlings of many plants.

Symptoms Seedlings attacked at ground level develop a water-soaked, discolored stem and topple over. Infected plants seldom recover.

Cultural control

  • Earliest seedings should go on raised beds in well-drained fields.
  • Use a precision seeder so seedlings are evenly spaced and not touching one another.

Chemical control

  • Treat seed with fungicide.
    • Acquire at 0.7 fl oz/100 lb seed plus a dye. For control of Pythium only. 24-hr reentry
    • Allegiance-FL at 0.75 fl oz/100 lb seed plus a dye. To control Pythium spp. only. See label for reentry restrictions.
    • Apron XL at 0.085 to 0.64 fl oz/100 lb seed plus a dye. For control of Pythium spp. See label for reentry restrictions.
    • Dynasty at 0.1 to 0.38 fl oz/100 lb seed plus a dye. 4-hr reentry.
    • Maxim 4FS at 0.08 to 0.16 fl oz/100 lb seed plus a dye. For control of pathogenic Fusarium and Rhizoctonia spp. See label for reentry restrictions.
    • Mertect at 0.002 mg ai/seed plus a dye. To control pathogenic Fusarium spp.
    • Spirato 480FS (Group 12) at 0.08 to 0.16 fl oz/100 lb seed plus a dye. 12-hr reentry.
    • 42-S Thiram at 8 fl oz/100 lb seed plus a dye. See label for reentry restrictions.
  • Soil applied fungicide.
    • Quadris Flowable at 0.4 to 0.8 fl oz/1000 row feet applied in a 7-inch or less band either in-furrow at planting or as a directed spray at cultivation. 4-hr reentry.
    • Regalia (Group P5) at 1 to 2 quarts/A as an in-furrow treatment. Does not benefit from the addition of an adjuvant. 4-hr reentry. O
    • Ridomil Gold SL at 0.51 to 1.3 pints/A may be applied preplant incorporated or as a band after planting where Pythium are a problem. 48-hr reentry.

Biological control

  • Actinovate AG at 3 to 12 oz/A as a soil drench at planting. 1-hr reentry. O
  • Actinovate Lawn & Garden at 0.5 to 1 teaspoon/gal water. H O
  • Amplitude at 3.2 to 4.8 fl oz/100 lb seed pieces, 6 to 8 fl oz per 1,000 ft row as an in-furrow treatment, or 3 to 4 quarts/A as a chemigation treatment on 14- to 21-day intervals. Preharvest interval is 0 days. 4-hr reentry. O
  • Double Nickel LC at 0.5 to 4.5 pints/A for soil application on 14- to 28-day intervals. Can be applied the day of harvest. 4-hr reentry. O
  • Prestop as a soil drench or incorporation into growing medium. 4-hr reentry. O
  • Rootshield Home and Garden at 1 to 3 Tbsp/gal water as a soil drench at planting. H O
  • SoilGard 12G at 0.5 to 10 lb/A at 4-week intervals will suppress Pythium and Rhizoctonia. See label for specific application types and timings. Can be applied on the day of harvest. O
  • Stargus at 6 to 8 fl oz per 1,000 ft row as an in-furrow treatment, 3 to 4 quarts/A as a soil drench on 10- to 14-day intervals, or 3 to 4 quarts/A as a chemigation drip treatment on 14- to 21-day intervals. Preharvest interval is 0 days. 4-hr reentry. O