Brown stripe

Brown stripe of sugar cane is a bacterial disease caused by the pathogen Burkholderia avenae (formerly known as Pseudomonas avenae). This pathogen specifically targets the leaves and vascular tissue of the sugar cane plant. It is considered an economically significant disease in tropical and subtropical regions, as it can drastically reduce the photosynthetic capacity of the plants, ultimately leading to lower sugar yields.

The primary host for this pathogen is sugar cane (Saccharum officinarum). The bacteria typically enter the plant tissue through stomata or wounds caused by insect feeding, hail, or mechanical handling during field operations. While plants at any stage can be infected, young, actively growing shoots are generally more vulnerable to severe outbreaks during favorable climatic windows.

Symptoms of Brown stripe include the appearance of narrow, elongated brown to reddish-brown stripes on the leaf blades. As the infection progresses, these stripes may coalesce, covering larger areas of the leaf surface and eventually leading to tissue necrosis. In humid conditions, a faint bacterial exudate may be present on the surface, and severe infections often lead to the premature drying and death of leaves.

The development and spread of Burkholderia avenae are strongly influenced by high humidity, heavy rainfall, and warm temperatures, typically ranging between 25°C and 30°C. The pathogen is easily disseminated via rain splashes, wind, and contaminated agricultural tools. Furthermore, using infected planting material (setts) remains one of the primary vectors for introducing the disease into new fields.

Effective management and prevention of Brown stripe require a combination of cultural and sanitary practices:

• Cultivation of resistant or tolerant sugar cane varieties suitable for the local climate.
• Using only certified, disease-free vegetative material for propagation.
• Implementing integrated pest management (IPM) to reduce insect damage that facilitates bacterial entry.
• Maintaining field hygiene, including the sterilization of cutting tools between rows.
• Promoting good air circulation within the canopy to reduce localized humidity.