Diseases

Downy mildew — broccoli

Brassica oleracea L. (Broccoli Group)

A fungal disease of broccoli caused by the oomycete Hyaloperonospora brassicae. It manifests as yellow spots on leaves with characteristic sporulation on the underside and systemic necrosis in the stems.

In the reference 43 varieties crop Broccoli, where this is mentioned in the description.

The causal agent of the disease is the oomycete Peronospora brassicae (synonyms Peronospora parasitica, Hyaloperonospora brassicae). The pathogen affects broccoli at all stages of development, posing the greatest danger to seedlings, which can lead to stunted growth or the death of young plants.

On the leaves, the infection appears as chlorotic, irregularly shaped spots bounded by veins, with a whitish, grayish, or gray-violet bloom of sporulation on the underside. Systemic infection of broccoli is characterized by the development of internal brown or black necrosis in the tissues of stems and floral stalks.

The pathogen has high physiological specialization and is represented by various races; however, their international classification is limited, and breeding more often relies on field trials of phenotypic response. In modern practice, molecular markers are used to identify cultivar resistance.

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

Sources8

Varieties of Broccoli 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.