For Malaysian durian farmers, managing the root zone of their prized trees is a constant balancing act. On one side, it’s essential to protect and nourish the root zone with a layer of organic material to enhance soil quality, nutrient access, and drought resilience. But on the other side looms the risk of Phytophthora, a notorious pathogen that causes durian canker. This destructive disease thrives in mulch and organic matter, where it can splash onto the trunk during rain, infecting the tree. As a result, many farmers keep their root zones scraped clean of vegetation and organic material, hoping to reduce canker incidence—yet this also weakens the tree’s overall resilience.
With these conflicting priorities, what can Malaysian durian farmers do? The answer may lie in a new approach: using biofertilizers with potential disease-inhibiting properties that allow farmers to benefit from root zone mulching while reducing disease risks.
The Root Zone Dilemma
The root zone is crucial for a durian tree’s health and productivity. Covering the root zone with a layer of organic material, like mulch or organic fertilizer, improves soil porosity and water absorption, reducing the risk of drought stress. These benefits are particularly valuable in Malaysia, where clay-heavy soils are prone to caking and compacting. When exposed to cycles of wetting, drying, and sun exposure, clay soils harden and form crusts that hinder nutrient uptake and root growth. A protective layer over the root zone prevents these issues, supporting the tree’s health and ability to access nutrients.
But there’s a catch. Phytophthora, the number one disease issue in durian, can make its home in mulch and other organic materials. The pathogen splashes onto the trunk from the root zone during rain, leading to Durian canker disease, which is often fatal to durian trees. The disease pressure is so significant that many farmers opt to keep their root zones bare, free of organic matter that might harbor Phytophthora palmivora. Unfortunately,
this leaves the root zone exposed to caking, nutrient loss, and other stresses, which weakens the trees over time.
A Potential Compromise: Biofertilizers with Disease-Inhibiting Properties
The problem seems like an unsolvable trade-off, but recent innovations in biofertilizers offer a promising solution. Biofertilizers with potential disease-inhibiting properties allow farmers to protect their root zones without inviting the risk of Phytophthora. By using organic biofertilizers that actively suppress pathogenic organisms, farmers can maintain soil health, improve nutrient availability, and still keep Phytophthora at bay.
One such example is Diptia®, a biofertilizer manufactured by Nutrition Technologies. Made from composted black soldier fly frass, Diptia® is high in organic matter (80%) and contains beneficial components like humic substances, amino acids, and Bacillus halotolerance bacteria. In laboratory tests, Diptia® has shown exciting potential to inhibit a broad range of plant pathogens, including Phytophthora. While these findings are promising, more research is needed on biofertiliser benefits in field settings.
Beyond its potential disease-inhibiting properties, Diptia® brings all the benefits of organic mulch without the downsides. Its high humic content improves soil structure and water retention, keeping the root zone more porous and better able to absorb water—a crucial feature in Malaysia’s clay-rich soils. Moreover, with a low carbon-to-nitrogen (C:N) ratio of 10, Diptia® doesn’t immobilize nitrogen, meaning it provides stable nutrition for the tree without drawing nitrogen away from the soil, a common issue with uncomposted organic matter.
Disease-Inhibitory Fertilizers: A New Chapter for Malaysian Durian
The development of biofertilizers like Diptia® represents an exciting step forward in Malaysian durian farming. This category of biofertilizers, with potential disease-suppressing properties, offers farmers a way to enjoy the benefits of mulching and root zone care—improving soil structure, boosting nutrient access, and enhancing drought resistance—while possibly reducing the risks of Durian Stem Canker.
Stem canker
Credit image to: (UPM) Nor Dalila Nor Danial, Norhayu Asib, Tosiah Sadi, Siti Izera Ismail
By incorporating biofertilizers with promising disease-inhibiting qualities into their management practices, durian farmers in Malaysia may be able to effectively protect the root zone and improve soil health while minimizing the threat of canker disease. This balanced approach has the potential to become a valuable tool for supporting the productivity and longevity of the thriving Malaysian durian sector.
Kommentare