What Happened
Cashew trees in Panama are losing productivity as disease, stress and weak orchard management combine to damage plantations in the country’s dry corridor, especially in producing areas such as Los Santos. The problem is not simply the presence of fungi, but the way neglected trees become vulnerable to them.
Eddy Barraza, a plant pathologist and professor at the Faculty of Agricultural Sciences at the University of Panama, says the tree can live with certain pathogens for a time, but once it weakens, those organisms spread more aggressively and can become irreversible.
One of the most severe threats is resinosis, linked to the fungus Lasiodiplodia theobromae. The pathogen can remain hidden in the plant until weather conditions, water stress or poor nutrition trigger its expansion.
A Problem That Has Been Building for Years
The decline has become more visible since 2017, when several fungi began appearing with greater intensity. Along with Lasiodiplodia theobromae, Colletotrichum gloeosporioides and Pestalotia heterocornis have played a major role in the damage.
Climatic shifts have made the situation worse. Irregular rainfall, higher temperatures and water stress create an environment that favors the spread of disease and weakens tree defenses. The impact usually begins in the canopy, then moves through the branches and ends up affecting fruit and overall tree structure.
Researchers describe the progression as a downward death pattern: leaves become spotted, flowers weaken, branches dry out and the tree gradually loses its ability to produce. In the Arco Seco, where each harvest depends on a delicate balance between climate and management, that decline has hit farmers hard.
What Farmers Can Do
The technical response is straightforward, but it requires discipline over time. Phytosanitary pruning removes sources of infection and improves tree structure. Proper fertilization strengthens the plant’s defenses. Timely irrigation reduces the stress that often activates disease.
Barraza stresses that these are not one-time measures. Cashew management must be maintained throughout the tree’s productive life if orchards are to remain viable. Without that consistency, even hardy trees can collapse under pressure.
Panamanian institutions, including the Ministry of Agricultural Development and the Institute for Agricultural Innovation, have renewed field support, technical training and outreach efforts, particularly in Los Santos. The work also includes testing more resistant varieties and developing technological packages with international support.
Why It Matters
Cashew has long been part of rural livelihoods and agricultural landscapes in Panama’s dry corridor. Its decline reflects a broader challenge in tropical farming: crops can survive harsh conditions, but only when management matches the environment.
The lesson from Panama’s cashew fields is clear. The crop is not failing on its own. It is failing when it is left without the care needed to keep disease, drought and decline from taking over.