Submitted to: Pisum Genetics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/9/2011
Publication Date: 6/15/2011
Citation: Attanayake, R., Glawe, D., Mcphee, K., Dugan, F.M., Chen, W. 2011. Potential alternative hosts for the pea powdery mildew pathogen Erysiphe trifolii. Pisum Genetics. 42:18-20. Interpretive Summary: Powdery mildew of pea is an important pathogen of dry pea and fresh pea in both field and greenhouse conditions. The disease is previously known to be caused by the fungal pathogen Erysiphe pisi. However, we recently discovered that another fungal species, E. trifolii also causes powdery mildew of pea. The host range of the newly discovered pathogen is unknown. This study was initiated to identify potential alternatve hosts of E. trifolii. E. trifolii was able to infect eleven of 12 plant species tested in the greenhouses. The following eleven plant species are potential alternative hosts of E. trifolii: Lathyrus latifolius, Lens culinaris, Melilotus albus, M. officinalis, Medicago lupulina, M. polymorpha, M. scutellata, Trifolium pratense, Vicia cracca, and V. faba. These findings have implications in devising strategies to manage powdery mildew of pea.
Technical Abstract: Powdery mildew of pea (Pisum sativum) is an important disease in the field and in the greenhouse. The most widely documented powdery mildew pathogen on pea is Erysiphe pisi, but E. baeumleri and E. trifolii have also been reported. We recently showed that E. trifolii is frequently found on pea in the US Pacific Northwest. Since detailed studies on host range of this pea powdery mildew were lacking, we tested common legume plants from the region as potential alternative hosts. Twelve species were used in greenhouse cross inoculation studies: Glycine max, Lathyrus latifolius, Lens culinaris, Melilotus albus, M. officinalis, Medicago lupulina, M. polymorpha, M. scutellata, Trifolium pratense, Vicia cracca, and V. faba. Except Glycine max, all the plant species tested in the greenhouse developed powdery mildew lesions in 10-14 days after inoculation with E. trifolii. Results showed that all the above legumes (except soybean) are potential alternative hosts for the pea powdery mildew pathogen E. trifolii. These findings have implications in devising strategies to manage powdery mildew of pea.