Root rot wilt

Root rot and wilt
    Causal organism: Fusarium solani, Pythium butleri and Phytophthora nicotianae var. nicotianae
    Symptoms of Fusarium solani affected plants
    • All the stages of the Plant are affected.
    • In young seedling stage the fungus causes pre and post emergence damping off of seedlings.
    • Drooping and yellowing of older branches and leaves. In the advance stage whole epical portion of the plant get died.
    • The tissue at collar region above and below the soil surface become brown and appear quite distinct from healthy tissue
    • Older plants when affected invariably wilt .
    Causal Organism : Fusarium solani
    • Etiology :Septate mycelia, intravascular
    • Vegetative spores : Chlamydospore (resting spores)
    • Sexual spores : Ascospore
    • Asexual spore : Micro and macro conidia
    • Primary Source of Inoculum : Chlamydospores in the soil and in crop debris
    • Secondary Source of Inoculum : Soil and air borne micro and macro conidia
    • Epidemiology :Temp. 30 - 320C, RH:90:92%,acidic pH(5.5:6.5), sandy loam soil, susceptable host
    Causal Organism :Rhizoctonia solani
    • Etiology : Septate mycelia, sub epidermal haustoria
    • Vegetative spores : Sclerotial bodies
    • Sexual spores :Absent
    • Asexual spore : Mycelial strands (sterile fungi)
    • Primary Source of Inoculum :Sclerotial bodies in soil
    • Secondary Source of Inoculum : soil borne Mycelial strands
    • Epidemiology : Warm weather,Temp.28 – 32oC, optimum moisture, succepteble host and neutral pH
    Management
    • Destroy affected debris and fallow summer plouging.
    • Avoid dense planting.
    • Use healthy plots and disease free planting material.
    • In nursery fumigation of the soil with methyl bromide and treating seeds with Captan @2gm/kg of seeds have been recommended.
    • Crop rotation - After three years crop of belladonna, rotation may be followed by planting the field with a crop like rye or wheat.

Last modified: Friday, 22 June 2012, 12:41 PM