Diseases

Tobacco blue mold

Nicotiana tabacum L.

A fungal disease of tobacco caused by the oomycete Peronospora tabacina, characterized by infection of seedlings and adult plants with the formation of chlorotic spots and a distinctive bluish mold.

In the reference 17 varieties crop Tobacco, where this is mentioned in the description.

The causative agent of the disease is the oomycete Peronospora tabacina Adam. In seedlings, the disease manifests as yellowish-green spots, leaf curling, and the rapid development of a gray-violet sporulation mold under high humidity conditions, which can lead to the death of seedlings within a few days.

On adult plants, the pathogen causes the appearance of rounded chlorotic spots bounded by leaf veins. In cases of systemic infection, leaf deformation, thinning of flower stalks, and tissue necrotization are observed. In dry weather, the mold may be absent, and the affected areas dry out rapidly.

Genetic resistance to the pathogen is based on the introgression of genes from wild species of the genus Nicotiana, including the NlRPT gene from Nicotiana langsdorffii, which provides protection through a hypersensitive response. There is no generally accepted system for classifying pathogen races in agronomic practice.

General information about the subject — on the page Downy mildew.

Sources8

Varieties of Tobacco mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.