Diseases

Downy mildew of wall rocket

Diplotaxis tenuifolia (L.) DC.

A fungal disease of wall rocket caused by the highly specific oomycete Hyaloperonospora diplotaxidis, which affects the crop at all stages of development.

In the reference 19 varieties crop Perennial wall-rocket, where this is mentioned in the description.

The causative agent of the disease is the oomycete Hyaloperonospora diplotaxidis, which has high species specificity for Diplotaxis tenuifolia. Pathogens of other cruciferous plants show significantly lower aggressiveness toward this crop. Established classifications of pathogen races are absent in the literature; however, the genetic diversity of isolates leads to the breakdown of resistance in breeding varieties.

Symptoms of the infection appear as light yellow chlorotic spots on the upper side of the leaves, which eventually become necrotic and brown. Under high humidity, a whitish sporulation coating forms on the underside of the leaf blades. The disease can also manifest as small dark or brownish-black specks that gradually spread across the leaf surface.

At present, standardized alphanumeric designations for pathogen resistance genes do not exist. The genetic resistance factors available in breeding programs, derived from wild forms of wall rocket, do not yet have an official nomenclature classification, and research is focused on further searching for sources of resistance within existing germplasm.

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

Sources8

Varieties of Perennial wall-rocket 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.