Maize redness

Maize redness is a serious plant disease caused by the Stolbur phytoplasma. It is a systemic infection that colonizes the phloem tissues of the host plant, severely disrupting its physiological functions, water balance, and nutrient translocation, which eventually leads to stunted growth and reduced crop productivity.

The primary host for this disease is maize, but the phytoplasma has a broad host range, infecting various weeds that act as long-term reservoirs for the pathogen. These alternative hosts are crucial for the survival of the phytoplasma during periods when maize is not present in the field, facilitating the carry-over of the infection.

The most distinctive symptom is the reddening of the leaves, typically starting from the leaf margins and advancing inwards. Infected plants often exhibit dwarfism, poor ear development, reduced kernel set, and in severe cases, total grain failure. This condition drastically reduces yield quality and quantity, causing significant economic losses for farmers.

The disease is transmitted by insect vectors, most notably planthoppers and leafhoppers like Hyalesthes obsoletus. These insects acquire the phytoplasma by feeding on infected plant tissues and subsequently transmit it to healthy maize plants during feeding. The rate of spread is highly dependent on the population density of these insect vectors and the availability of infected host plants nearby.

• Implement integrated weed management to eliminate reservoir hosts of the pathogen.
• Apply systemic insecticides to control the populations of insect vectors during critical periods.
• Practice spatial isolation between maize fields and areas prone to high weed infestation.
• Select resistant maize hybrids suitable for regions where the disease is endemic.
• Maintain optimal agronomic practices to ensure vigorous plant growth, which may mitigate disease impact.