1. Conditions That Favor Disease Development
Phytophthora disease in durian tends to develop strongly when:
Weather: The disease thrives in the rainy season with high humidity.
Soil: Poorly drained, waterlogged soil with low oxygen around roots increases infection risk.
Plant health: Weak root systems and reduced tree resistance make trees more vulnerable.
Pathogen survival: Phytophthora organisms live in soil and spread rapidly through water movement.
2. Common Types of Phytophthora Damage in Durian
a. Root Rot with Sap Exudation
This disease begins at the root and lower stem where the pathogen infects weakened or damaged tissue. Early signs include dark, wet lesions and brown or reddish sap oozing from the trunk. Internal tissues rot and become soft, hindering water and nutrient transport. Under continuous wet conditions, the disease may spread up the trunk and cause yellowing foliage, leaf drop, poor growth, or even tree death.
b. Leaf Blight
Phytophthora infections often spread from wet soil onto foliage during rainy periods. Small brown or dark lesions appear on leaves, rapidly enlarging and causing leaves to wilt and fall prematurely. This reduces photosynthesis and weakens tree vigor.
c. Fruit Rot
Infected fruit shows small dark brown lesions that expand, sometimes with white fungal growth on the surface. Affected fruit often drops prematurely or decays before ripening, directly impacting yield and quality.
d. Root Decay
In wet soil, spores enter through weakened roots, causing brown to black soft rot. Damaged roots lose their ability to absorb water and nutrients, leading to stunted growth, wilted leaves, and tree decline
3. Management Practices
To effectively manage Phytophthora diseases in durian, combine cultural, sanitation, and chemical strategies for an integrated approach.
A. Cultural Practices
✔ Ensure good drainage by planting on raised beds and creating drainage channels — avoid waterlogging.
✔ Do not plant trees too densely; prune to improve air circulation and reduce humidity.
✔ Apply balanced fertilization (N–P–K) and organic matter to boost tree health and resistance.
✔ Avoid mechanical damage to roots and trunks, as wounds provide entry points for pathogens.
B. Orchard Hygiene
✔ Regularly collect and destroy fallen diseased leaves and fruit to reduce pathogen reservoirs.
✔ When root rot or canker is detected, remove diseased tissues and keep the area dry.
✔ Sterilize pruning tools between trees to avoid spreading fungal spores.
C. Chemical Control
For rapid control and to limit spread, appropriate fungicide use plays an important role. One effective solution is Jepway 40SC (Minh Long Agro). It can be applied in different ways depending on the affected area:
Canopy spray — Prevent and treat leaf blight and fruit rot during rainy, humid conditions (mix at recommended rates and spray evenly).
Trunk treatment — Remove diseased bark, allow surfaces to dry, then apply fungicide directly to infected zones.
Root zone drench — Apply to the soil near roots to reduce pathogen populations and limit re-infection.
Follow label instructions on dosage and timing for effective control while minimizing environmental impact.
Conclusion
Phytophthora diseases are serious threats to durian production, capable of infecting trees at all stages and damaging roots, stems, leaves, and fruit. By using an integrated disease management strategy — including cultivation practices, orchard sanitation, and correct application of fungicides — farmers can reduce disease pressure, protect tree health, and improve yield and quality outcomes. actahort.org
📞 For technical advice and product guidance, contact Minh Long Agro or your nearest authorized dealer.
authorized dealer.
MINH LONG AGRO CO., LTD.
📍 Address: 137 Tran Xuan Soan Street, Tan Thuan Ward, Ho Chi Minh City
📞 Hotline: 1900 8982
🌐 Website: www.minhlongagro.com