June 24, 2017

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

Onion ipmPIPE 2013 ID State Commentary 08 Aug

 

Idaho Commentary

Onion Crop Growth Stage and Status Last Modified: 08/08/13

Onion crop development is normal, mostly Stage 8. Generally high level of thrips populations and significant thrips feeding injury to the leaves and widespread incidence of IYSV symptoms observed in many fields.

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 08/08/13

Daytime mean high temperature between low to high 90s F. No significant precipitation.

Insect Scouting, Outlook and Management Last Modified: 08/08/13

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 47 and 70. Some growers’ fields show severe leaf damage due to thrips feeding, and drying-up of leaves.

Maggots

No surveys or reports at this time

Other

No surveys or reports at this time

Disease Scouting, Outlook and Management Last Modified: 08/08/13

Iris yellow spot virus

Widespread incidence of presumptive IYSV symptoms in many fields. In some growers’ fields, these IYSV symptoms led to moderately severe drying of leaves.

Soil-borne Diseases (Damping Off, Pink Root, Fusarium)

Limited areas with Fusarium plate rot/root rot symptoms have been noted in a couple of growers’ fields.

Fungal Diseases (purple blotch, downy mildew, Botrytis)

No significant problems were observed

Bacterial Diseases (Xanthomonas, center rot, soft rots)

No surveys or reports at this time Onion Pathologist S. Krishna Mohan Professor of Plant Pathology University of Idaho Email:kmohan@uidaho.edu