VIRUSES

Turnip mosaic virus (TuMV), Cauliflower mosaic virus (CaMV), Turnip yellow mosaic virus (TYMV)

Host range:
CaMV and TYMV are restricted to the Cruciferaceae family only but TuMV has broader host range including poppy and some other species.

Occurrence and importance:
TuMV and CaMV occur time to time on some plants in crops but TYMV can heavily infect mainly Chinese cabbage. Infected plants don´t form consumable part at all or it is of bad quality.

Symptoms and confusable diseases:

Typical symptoms are mosaics, vein clearing, leaf distortions and plant stunting. For layman it is difficult to discriminate symptoms of these viruses each from others with the exception of those of TYMV on Chinese cabbage where severe yellow mosaic occurs.

 

 

 

 

Disease cycle:
All viruses can overwinter on winter rape and Cruciferous weeds as well as on transplants intended for planting for seed production. TYMV is also seedborne. TuMV and CaMV are transmitted by aphids (Brevicoryne brassiceae, Myzus persiceae) in nonpersistent manner, TYMV is transmitted by flea beetles.

Control:
- elimination of weeds, aphids, flea-beetles, and infected plants,
- healthy seed crops (for TYMV),
- isolation from seed crops,
- covering smaller plots by white textile foil as protection against vectors.