Noble Dendrobium with Fusarium Wilt: Prevention & Cure
Dendrobium nobile
Fusarium wilt is a serious fungal disease caused by the soil-borne fungus Fusarium oxysporum. The fungus invades roots and blocks the water-conducting vessels (xylem) of the plant, causing progressive wilting and eventual death. Host-specific forms of the pathogen exist that attack different plant species.
ð Symptoms
- âĒ Wilting during the hottest part of the day with recovery at night (early stage)
- âĒ Asymmetrical yellowing of leaves (one side of plant or leaflets)
- âĒ Progressive upward wilting from the stem base
- âĒ Dark red to brown discoloration of vascular tissues
- âĒ Stunted growth and dwarfism
- âĒ Pale green to golden yellow foliage
- âĒ Progressive death of leaves from bottom to top
â Possible Causes
- â Infection by soil-borne fungus Fusarium oxysporum
- â Entry through roots, especially wounds
- â Soil temperature above 75°F (24°C) favors development
- â Acidic soil and excess nitrogen increase susceptibility
- â Contaminated tools and infected soil
- â Contaminated transplants and seeds
ð Treatment
Quick Fixes
Remove Plant
Immediately remove entire infected plant with roots. Dispose in sealed trash (DO NOT compost).
Disinfect Area
Spray area with diluted bleach solution (1:10). Allow to dry.
Apply Biofungicide
If available, immediately apply Mycostop or Trichoderma to affected soil.
Isolate Area
DO NOT plant anything in same area for at least 6 months. Fusarium remains in soil.
Organic Treatment
Immediate Removal
Completely remove infected plant including all roots. Do not compost - burn or dispose in sealed trash.
Tool Disinfection
Clean all tools with 10% bleach solution for 5 minutes. Allow to dry completely in sun.
Soil Solarization
Cover affected area with clear plastic for 4-6 weeks in summer. Heat eliminates pathogens.
pH Correction
Test soil pH. If acidic, add lime to raise pH to 7.0-7.2. Fusarium prefers acidic soils.
Biological Inoculation
Add well-cured compost rich in Trichoderma or apply biological product (Mycostop). Wait 2 weeks before replanting.
Replant with Resistant Varieties
Use ONLY Fusarium-resistant varieties. Check certification. Maintain good drainage.
ðĄïļ Prevention
- â Use Fusarium-resistant varieties (most effective method)
- â Crop rotation for 3-5 years away from susceptible plants
- â Raise soil pH to 7 in acidic soils
- â Avoid excessive nitrogen in fertilization
- â Use certified disease-free seeds and transplants
- â Clean soil and debris from all tools
- â Improve soil drainage
- â Avoid root injuries during transplanting
- â Soil solarization in infected areas
ðą Care Guide: Noble Dendrobium
ð§ How to Water
Water thoroughly once a week during the growing season (spring-summer), allowing the mix to almost dry between waterings. Reduce watering significantly in fall and winter, just enough to prevent canes from shriveling. Resume normal watering when flower buds appear.
âïļ Lighting
Provide bright indirect light, ideally near an east-facing window or shaded south-facing window. Avoid direct midday sun which can burn the leaves. Good light is essential for flowering.
ðŠī Ideal Soil
Use a well-draining orchid bark mix. The plant is epiphytic in nature and requires excellent drainage. Repot every 2-3 years when the medium breaks down or roots outgrow the pot.