Polemovirus PnLV

Polemovirus PnLV (Pelargonium necrotic leaf curl virus) is a serious viral disease affecting ornamental crops. This pathogen, belonging to the Polemovirus genus, acts as a systemic infection that disrupts essential physiological processes, significantly impacting the structural and aesthetic integrity of infected host plants.

The primary host for this virus is the Pelargonium species. Being a systemic pathogen, PnLV spreads throughout the entire vascular system of the plant, making it difficult to eradicate once the infection becomes established within the internal tissues of the specimen.

Symptoms of the disease typically include necrotic rings, chlorotic spotting, and leaf distortion. In severe cases, infected plants exhibit stunted growth, shortened internodes, and reduced flowering capability. These visual markers often lead to a significant decline in the commercial value of the crop.

Transmission and development of the virus are most common via vegetative propagation. Using infected cuttings as starting material is the primary mode of spreading the disease. Furthermore, the virus can be mechanically transmitted through contaminated pruning tools or contact during greenhouse maintenance, especially under high humidity conditions that favor plant stress.

The severity of PnLV lies in the lack of curative treatments for viral diseases in plants. Therefore, management focuses entirely on exclusion and sanitation. Key prevention strategies include sourcing certified virus-free propagation material, implementing strict hygiene protocols such as disinfecting cutting tools with appropriate solutions, and adopting a zero-tolerance policy by rogueing and destroying any plant that displays characteristic symptoms of the infection.