June 24, 2017

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

spring_onionR

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

 

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2013 ID State Commentary 25 Jul

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 07/25/13

Onion crop development is normal, mostly Stage 7. Generally high level of thrips populations and significant thrips feeding injury to the leaves observed in many fields.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 07/25/13

Daytime mean high temperature varying between 95 to 104 F. No significant precipitation.

 

Insect Scouting, Outlook and Management Last Modified: 07/25/13

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 37 and 74. 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: 07/25/13

Iris yellow spot virus

Presumptive IYSV symptoms have been observed on a few plants in all of the sentinel plots and in some commercial fields. In a few growers’ fields, the IYSV symptoms were moderately severe

 

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

 

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2013 ID State Commentary 12 Jul

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 07/12/13

Onion crop development is normal, mostly, Stage 7 (bulb diameter mostly 4-6 cm). Thrips populations increasing; significant thrips feeding injury to the leaves.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 07/12/13

Weather conditions are normal for this time of the year. Few isolated hail incidents.

 

Insect Scouting, Outlook and Management Last Modified: 07/12/13

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 18 and 56.   

Maggots

No surveys or reports at this time

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 07/12/13

Iris yellow spot virus

Presumptive IYSV symptoms have been observed on a few plants in all of the sentinel plots and in some commercial fields.

 

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

No significant problems have been observed.

 

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

 

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2013 ID State Commentary 05 Jun

Idaho Commentary

Onion Crop Growth Stage and Status Last Modified: 06/05/13

Onion crop development is normal, mostly 5 to 6 leaf stage. Low levels of thrips infestation. No

significant disease or pest problems. A fee fields show herbicide-related damage.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 06/05/13

Weather conditions are normal for this time of the year.

 

Insect Scouting, Outlook and Management Last Modified: 06/05/13

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per

plant varied between 2 and 7.

Maggots

No surveys or reports at this time

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 06/05/13

Iris yellow spot virus

No symptoms have been observed.

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

No significant problems have been observed.

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

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2012 ID State Commentary 07 Sep

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 09/07/12

Most of the fields are being lifted/topped/harvested. Dry weather conditions are helping with rapid field curing of topped onions

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 09/07/12

Weather continues to be generally hot and dry.

 

Insect Scouting, Outlook and Management Last Modified: 09/07/12

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 197 to 288.  Symptoms of significant thrips damage is evident in many fields.

Maggots 

No surveys or reports at this time

 

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 09/07/12

Iris yellow spot virus

Widespread incidence of IYSV symptoms was observed in all the four sentinel plots.  Medium to high incidence of IYSV symptoms was observed in most of the commercial onion bulb fields, many fields showing premature drying of leaves.

 

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

Some fields showing areas of significant pink root damage.

 

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

 

Krishna Mohan – ID State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2012 ID State Commentary 24 Aug

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 08/24/12

Onion crop development is normal, plants mostly in developmental stage 9 or 10.  Several fields are being harvested. Dry weather conditions are helping with rapid field curing of topped onions

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 08/24/12

Weather continues to be generally hot and dry.

 

Insect Scouting, Outlook and Management Last Modified: 08/24/12

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 129 to 327.  Symptoms of significant thrips damage is evident in many fields.

Maggots

No surveys or reports at this time

 

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 08/24/12

Iris yellow spot virus

Widespread incidence of IYSV symptoms was observed in all the four sentinel plots.  Medium to high incidence of IYSV symptoms was observed in a most of the commercial onion bulb fields, many fields showing premature drying of leaves.

 

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

Some fields showing areas of significant pink root damage.

 

Fungal Diseases (purple blotch, downy mildew, Botrytis)

A few bulb samples with side rot (Botrytis gray mold rot) were received in the diagnostic lab.

 

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

 

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2012 ID State Commentary 27 Jul

 

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 07/27/12

Onion crop development is normal, plants mostly in developmental stage 7.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 07/27/12

Weather continues to be generally very hot (several days with maximum temperature around100) and very dry.

 

Insect Scouting, Outlook and Management Last Modified: 07/27/12

Thrips

Survey of the four sentinel (observation) plots: Average number of thrips (larvae + adults) per plant varied between 79 to 188.  Symptoms of significant thrips damage was evident in some fields.

 

Maggots

No surveys or reports at this time

 

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 07/27/12

Iris yellow spot virus

Low level of incidence (1 to 2% plants) of IYSV symptoms were observed in all the four sentinel plots.  Low incidence of IYSV symptoms was observed in a few commercial onion bulb fields.

 

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

No surveys or reports at this time

 

Fungal Diseases (purple blotch, downy mildew, Botrytis)

No surveys or reports at this time

 

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

 

Krishna Mohan – ID State Commentary – Onion ipmPIPE

onion bulbs

Onion ipmPIPE 2012 ID State Commentary 29 Jun

 

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 06/29/12

Onion crop development is normal, plants mostly developmental stage 4 and a few in stage 5.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 06/29/12

Weather continues to be generally hot and dry.

 

Insect Scouting, Outlook and Management Last Modified: 06/29/12

Thrips

Survey of the four sentinel (observation) plots: Average number of adults per plant ranged from

6 to 22.  Average number of larvae per plant ranged from 16 to 49.  Symptoms of significant

thrips damage was evident in many plants.

 

Maggots

No surveys or reports at this time

 

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 06/29/12

Iris yellow spot virus

Low level of incidence (<1% plants) of IYSV symptoms were observed in one of the four

sentinel plots.  Low incidence of IYSV symptoms were observed in a few commercial onion

bulb fields.  Some onion seed fields (planted in Fall 2011) showed extensive incidence (more

than 60% plants with symptoms) of IYSV.  In a seed production field, extensive losses are

observed because more than 50% scapes with severe IYSV lesions toppled over because of

umbel weight even before seed set.

 

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

No surveys or reports at this time

 

Fungal Diseases (purple blotch, downy mildew, Botrytis)

No surveys or reports at this time

 

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

 

Krishna Mohan – Idaho State Commentary – Onion ipmPIPE

onion bulbs

 

Idaho Commentary

 

Onion Crop Growth Stage and Status Last Modified: 06/15/12

Onion crop development is normal, plants mostly in 4-6 leaf stage.

 

Weather Impacts (temperature, rain, hail, freezing) Last Modified: 06/15/12

Weather continues to be generally warm and dry with occasional showers.

 

Insect Scouting, Outlook and Management Last Modified: 06/15/12

Thrips 

First survey of the four sentinel (observation) plots: In three of the plots there were an average of 3 adults and 4 larvae per plant.  In the fourth plot, there were 5 adults and 24 larvae per plant.

 

Maggots 

No surveys or reports at this time

 

Other

No surveys or reports at this time

 

Disease Scouting, Outlook and Management Last Modified: 06/15/12

Iris yellow spot virus

No surveys or reports at this time

 

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

No surveys or reports at this time

 

Fungal Diseases (purple blotch, downy mildew, Botrytis)

No surveys or reports at this time

 

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

Krishna Mohan – Idaho

onion bulbs

Sept 08, 2011 Harvesting of Onions in another 8 to 15 days.Crop growth is good with hot and dry conditions.Apart from confirmed IYSV, no other disease to report. Minor incidence of Cladosoprium from the dead and dying leaf tips. Thrips encountered in all the plots and their numbers are subsiding with the approaching harvest.