Botryosphaeria theobromae

Botryosphaeria theobromae is a destructive fungal pathogen within the Ascomycota phylum, known for causing a variety of plant diseases. It is a highly polyphagous fungus, meaning it thrives on a vast range of hosts, significantly impacting agricultural and horticultural production globally.

The fungus is primarily responsible for conditions such as branch dieback, stem cankers, and post-harvest fruit rots. Key crops affected include tropical species like cocoa and mango, as well as various temperate fruit trees, where the infection often leads to severe vascular browning and tissue necrosis.

The life cycle of the pathogen involves the production of pycnidia, which release conidia under suitable environmental conditions. These spores are disseminated via wind, water splashes, and insect vectors, entering the host plant through wounds, pruning cuts, or natural lenticels. The pathogen can survive as a latent infection or saprophytically in dead organic matter.

The development of the disease is favored by high temperatures and humidity. Environmental stress, such as drought, nutrient deficiency, or physical damage from storm events, drastically reduces a plant's ability to defend against the colonizing hyphae, facilitating the progression of the rot.

Effective management of Botryosphaeria theobromae is centered on integrated pest management practices. Key strategies include:

• Pruning and removal of infected branches to reduce inoculum
• Application of protective fungicides during pruning season
• Ensuring proper plant hydration to mitigate stress-induced susceptibility
• Sterilization of pruning equipment between trees
• Use of resistant rootstocks where available