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Contact

College of Agricultural & Life Sciences

Physical Address:
E. J. Iddings Agricultural Science Laboratory
606 S Rayburn St

Mailing Address:
875 Perimeter Drive MS 2331
Moscow, ID 83844-2331

Phone: 208-885-6681

Fax: 208-885-6654

Email: ag@uidaho.edu

Web: uidaho.edu/cals/potatoes

Location

Mailing Address:
1693 S 2700 W
Aberdeen, ID 83210

Phone: 208-397-4181

Fax: 208-397-4311

Web: uidaho.edu/cals/aberdeen

Location

Mailing Address:
3793 North 3600 East
Kimberly ID 83341-5076

Phone: 208-423-4691

Fax: 208-423-6699

Web: uidaho.edu/cals/kimberly

Location

Mailing Address:
29603 U of I Lane
Parma, ID 83660-6699

Phone: 208-722-6701

Fax: 208-722-6708

Web: uidaho.edu/cals/parma

Location

News, updates & conferences

July 18, 2019

First Lso-positive psyllids found in Idaho

This week we had traps deployed in 83 of the 83 fields (100 percent) monitored this year and we found a total of 59 psyllids across 29 (34.9 percent) of the 83 monitored fields.

Psyllids were collected on sticky traps in potato in the following counties: Payette (1 field), Canyon (11 fields), Elmore (3 fields), Twin Falls (10 fields), Jerome (3 fields) and Cassia (1 field).

From last week’s samples, five psyllids tested positive for Lso (liberibacter), the bacterium associated with zebra chip disease (ZC). These hot psyllids were collected from one field in Payette County and two fields in Twin Falls County. In addition, one psyllid collected from a field in Canyon County in mid-June (before our monitoring program had officially started) tested positive for Lso.

Given the incidence of Lso observed in psyllids, we strongly urge growers and crop consultants to maintain their IPM programs.

We apologize for not having “heat maps” yet this week. We hope to have them generated before next week and posted on our website.

July 18, 2019

First Lso-positive psyllids found in Idaho

This week we had traps deployed in 83 of the 83 fields (100 percent) monitored this year and we found a total of 59 psyllids across 29 (34.9 percent) of the 83 monitored fields.

Psyllids were collected on sticky traps in potato in the following counties: Payette (1 field), Canyon (11 fields), Elmore (3 fields), Twin Falls (10 fields), Jerome (3 fields) and Cassia (1 field).

From last week’s samples, five psyllids tested positive for Lso (liberibacter), the bacterium associated with zebra chip disease (ZC). These hot psyllids were collected from one field in Payette County and two fields in Twin Falls County. In addition, one psyllid collected from a field in Canyon County in mid-June (before our monitoring program had officially started) tested positive for Lso.

Given the incidence of Lso observed in psyllids, we strongly urge growers and crop consultants to maintain their IPM programs.

We apologize for not having “heat maps” yet this week. We hope to have them generated before next week and posted on our website.


July 11, 2019

The 2019 University of Idaho monitoring program for potato psyllids and liberibacter (Lso), the bacterium associated with zebra chip disease (ZC), is underway. Following recommendations from our ZC Advisory Committee last year, we shortened the duration of the program. We also plan to post weekly updates by Thursday each week instead of Friday.

This week, we collected 38 psyllids from sticky cards (across 20 sites).

Psyllids were collected on sticky traps in potato in the following counties: Payette (2 fields), Canyon (7 fields), Owyhee (2 fields), Elmore (3 fields), Twin Falls (3 fields), Jerome (2 fields) and Minidoka (1 field).

We had traps deployed in 53 of the 83 fields (63.8 percent) monitored this year and found psyllids in 19 of the monitored fields (37.7%).

During the previous week (before the monitoring program officially began), we collected 14 psyllids across 7 of 25 fields that were monitored (psyllids were captured in Payette, Canyon and Owyhee counties).

All psyllids tested so far have been negative for Lso. Nevertheless, we urge growers and crop consultants to maintain their IPM programs.

“Heat maps” of this week’s results will not be made given that a relatively low number of psyllids and sites (traps in several fields were just deployed this week) tends to result in skewed maps.


June 28, 2019

The University of Idaho, in collaboration with crop consultants across the state, will continue our monitoring program for potato psyllids, zebra chip disease and liberibacter (Lso), the bacterium associated with zebra chip. The monitoring program covers commercial potato fields throughout southern Idaho and is funded in part by the Idaho Potato Commission, USDA and generous in-kind contributions by our collaborators.

Following recommendations from our ZC Advisory Committee last year, we are shortening the duration of the program. We still plan to monitor about 100 fields across the state, but only with four sticky traps per field rather than the more intense sampling that was conducted on some fields in the past.

The first official deployment of sticky traps for the program will occur next week. However, following earlier than usual observation of potato psyllids in Oregon, we began deploying traps on a limited basis over the last three weeks. During the week of June 10, we captured 22 potato psyllids across six fields in Canyon County and one psyllid in a field in Payette County. During the week of June 17, we captured one psyllid in each of two fields in Canyon County and three psyllids across two fields in Payette County. We have yet to observe potato psyllids in Twin Falls County after three weeks of monitoring in a few fields. Over the last two weeks, we found psyllids in eight of 12 fields (67 percent) and four of 23 fields (17 percent) being monitored, respectively.

It should be noted that observation of potato psyllids in Idaho during June is not at all unexpected. We typically would find our first psyllids during mid-May.


Oct. 5, 2018

Final 2018 psyllid monitoring update

This week we collected two psyllids from sticky traps in one intense field in Twin Falls County. We only had traps deployed in two fields given that all of the other fields in the monitoring program had been vine killed or harvested. 

One of the psyllids collected last week tested positive for Lso (liberibacter), the bacterium that causes zebra chip. This is only the third psyllid this season to test positive, and this year still has shown the lowest overall incidence in Lso for any season we have been monitoring. Nevertheless, this finding underscores the importance of maintaining an IPM program through the end of the season. We have found that ZC can develop in tubers that were inoculated with Lso-positive psyllids as late as two weeks (and in rare cases one week) before vine kill.

This week’s report concludes the University of Idaho psyllid/Lso monitoring program. We will only provide an update next Friday if we detect Lso in the psyllids collected this week.

Thanks to all of the growers, crop consultants and other industry folks who contributed to this work.

A summary of this year’s results is expected to be presented at the Idaho Association of Plant Protection meeting in Twin Falls in November and at the Idaho Potato Conference.


Sept. 28, 2018

Psyllid update

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (three fields) and Twin Falls (one field).

This week, we collected nine psyllids from sticky cards (across four intense sites).

Most of the 95 fields that were in the monitoring program have been vine killed or harvested. We had traps deployed in all six of the remaining fields and found psyllids in four of them (66.7 percent). 

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence has been considerably lower than in all previous years. Nevertheless, we urge growers and crop consultants to maintain their IPM programs. We have found that ZC can develop in tubers that were inoculated with Lso-positive psyllids as late as two weeks (and in rare cases one week) before vine kill.


Sept. 21, 2018

Psyllid update

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (four fields), Jerome (one field) and Twin Falls (one field).

This week, we collected 40 psyllids from sticky cards (across six intense sites and 0 light sites). We also collected a few eggs and nymphs in leaf samples at two sites in Canyon County; when we have found immature psyllids in the past, they have typically occurred very late in the season as is the case here.

Most of the 95 fields that were in the monitoring program have been vine killed or harvested. We had traps deployed in all 14 of the remaining fields and found psyllids in six of them (43 percent). There are now just a handful of fields being monitored for next week’s report.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence has been considerably lower than in all previous years. Nevertheless, we urge growers and crop consultants to maintain their IPM programs. We have found that ZC can develop in tubers that were inoculated with Lso-positive psyllids as late as two weeks (and in rare cases one week) before vine kill.

“Heat maps” of this week’s results will not be made given that the low number of sites remaining tends to result in skewed maps. 


Sept. 14, 2018

Psyllid update

Sept. 14 east heat mapPsyllids were collected this week on sticky traps in potato in the following counties: Canyon (four fields), Twin Falls (two fields) and Cassia (six fields).

This week, we collected 84 psyllids from sticky cards (across seven light sites and five intense sites).

Many of the 95 fields that were in the monitoring program are being vine killed or harvested. We had traps deployed in all 26 of the remaining fields and found psyllids in 12 of these 26 fields (46.2 percent).

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years. Nevertheless, we urge growers and crop consultants to have an IPM program in place.

Sept. 14 west heat map

With so few sites still being monitored this late in the season, it is possible that the heat maps may appear a bit skewed.


Sept. 7, 2018

Psyllid update

Sept. 7 east heat mapPsyllids were collected this week on sticky traps in potato in the following counties: Canyon (two fields), Twin Falls (one field) and Cassia (four fields).

This week, we collected 19 psyllids from sticky cards (across four light sites and three intense sites).

We had traps deployed in all 32 of the 32 fields (100 percent) monitored and found psyllids in seven of the monitored fields (21.8 percent). 63 of the 95 total fields that we were sampling have been vine-killed.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years. Nevertheless, we urge growers and crop consultants to have an IPM program in place.

Sept. 7 west heat map 


Aug. 31, 2018

Psyllid update

Aug. 31 east heat mapPsyllids were collected this week on sticky traps in potato in the following counties: Canyon (nine fields), Owyhee (two fields), Elmore (one field), Payette (one field), Jerome (one field), Twin Falls (two fields) and Cassia (one field).

This week, we collected 34 psyllids from sticky cards (across 13 light sites and four intense sites).

We had traps deployed in all 89 of the 89 fields (100 percent) monitored this year and found psyllids in 17 of the monitored fields (19.1 percent). Six of the 95 total fields that we were sampling have been vine-killed.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years. Nevertheless, we urge growers and crop consultants to have an IPM program in place.

Aug. 31 west heat map


Aug. 24, 2018

Psyllid update

heat west map for Aug. 24Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (10 fields), Elmore (one field), Twin Falls (two fields) and Cassia (one field).

This week, we collected 30 psyllids from sticky cards (across nine light sites and five intense sites).

We had traps deployed in all 95 of the 95 fields (100 percent) monitored this year and found psyllids in 14 of the monitored fields (14.7 percent).

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years. Nevertheless, we urge growers and crop consultants to have an IPM program in place.

heat west map for Aug. 24


Aug. 17, 2018

Psyllid update

Heat maps describe predicted psyllid densities across the landscape, based on our trap counts and on predictive models developed over six years of psyllid monitoring in IdahoPsyllids were collected this week on sticky traps in potato in the following counties: Canyon (9 fields), Payette (one field), Twin Falls (three fields), Jerome (one field), Cassia (one field) and Bannock (one field).

This week, we collected 36 psyllids from sticky cards (across 12 light sites and four intense sites).

We had traps deployed in all 95 of the 95 fields (100 percent) monitored this year and found psyllids in 16 of the monitored fields (16.8 percent). However, we are still waiting to receive card data from four sites.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years. Nevertheless, we urge growers and crop consultants to have an IPM program in place.

Heat maps describe predicted psyllid densities across the landscape, based on our trap counts and on predictive models developed over six years of psyllid monitoring in Idaho 


Aug. 10, 2018

Psyllid update

August 10 east heat map for potato pests

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (10 fields), Payette (one field), Twin Falls (one field), Jerome (one field), Cassia (three fields), Minidoka (one field), Power (one field) and Oneida (one field).

This week, we collected 36 psyllids from sticky cards (across 15 light sites and four intense sites).

We had traps deployed in all 95 of the 95 fields (100 percent) monitored this year and found psyllids in 19 of the monitored fields (20 percent). However, we are still waiting to receive card data from three sites.

This week we also collected one psyllid from vacuum sampling in one Canyon county field. 

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.

Although psyllid numbers continue to be relatively low thus far this year, we are now starting to see a few more captures in eastern Idaho. With only two Lso-positive psyllids found to date, percent incidence is currently considerably lower than in most previous years.

Nevertheless, we urge growers and crop consultants to have an IPM program in place.

August 10 west heat map for potato pests 


Aug. 3, 2018

Psyllid update

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (12 fields), Cassia (one field), Jerome (one field), Payette (one field) and Twin Falls (two fields).

This week, we collected 32 psyllids from sticky cards (across 11 light sites and six intense sites).

We had traps deployed in all 96 of the 96 fields (100 percent) monitored this year and found psyllids in 17 of the monitored fields (17.7 percent).

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.

Psyllid numbers continue to be relatively low thus far this year. With only two Lso-positive psyllids found to date, percent incidence is currently lower than what has typically been found during most previous years.

Nevertheless, we urge growers and crop consultants to have an IPM program in place.

Map: moderate (.5-1.50) from Emmett to Marsing, low (.24-.5) from Washington Mill to Triangle and west and none detected (less than .24) right around Melba and everywhere else in southwest Idaho.


July 27, 2018

Psyllid update

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (11 fields), Cassia (one field), Minidoka (one field), Payette (one field) and Twin Falls (one field).

This week, we collected 30 psyllids from sticky cards (across 13 light sites and two intense sites).

We had traps deployed in 96 of the estimated 96 fields (100 percent) monitored this year and found psyllids in 15 of the monitored fields (19.8 percent). However, we are still waiting to receive cards from 13 sites.

Testing of last week’s psyllids for Lso has been delayed due to the Potato Association of America meeting this week.

Psyllid numbers remain relatively low thus far this year. With two Lso-positive psyllids found to date, percent incidence is similar to what has typically been found during most previous years.

Nevertheless, we urge growers and crop consultants to have an IPM program in place.


July 20, 2018

Psyllid update 

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (10 fields), Cassia (three fields), Elmore (one field), Minidoka (two fields), Payette (one field) and Twin Falls (two fields).

This week, we collected 29 psyllids from sticky cards (20 light sites and nine intense sites).

We had traps deployed in 93 of the estimated 96 fields (96 percent) that will be monitored this year and found psyllids in 19 of the monitored fields (20.4 percent).

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.

Psyllid numbers remain relatively low thus far this year. With two Lso-positive psyllids found to date, percent incidence is similar to what has typically been found during most previous years.

Nevertheless, we urge growers and crop consultants to have an IPM program in place.


July 13, 2018

Second Lso-positive potato psyllid this year

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (eight fields), Cassia (three fields), Owyhee (one field), Jerome (two fields) and Twin Falls (three fields).

This week, we collected 31 psyllids from sticky cards (13 light sites and four intense sites). 

We had traps deployed in 92 of the estimated 96 fields (96 percent) that will be monitored this year and found psyllids in 17 of the monitored fields (18.5 percent).

One psyllid collected last week in Canyon County tested positive for Lso (liberibacter), the bacterium that causes zebra chip.

Psyllid numbers remain relatively low thus far this year. With two Lso-positive psyllids found to date, percent incidence is similar to what has typically been found during most previous years.

Nevertheless, we urge growers and crop consultants to have an IPM program in place.


July 6, 2018

First Lso-positive potato psyllid

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (four fields), Owyhee (two fields), Gooding (one field) and Twin Falls (one field).

This week, we collected 13 psyllids from sticky cards (seven light sites and one intense site).

We had traps deployed in 93 of the estimated 97 fields (95 percent) that will be monitored this year and found psyllids in eight of the monitored fields (8.6 percent). However, we are still waiting to receive cards from eight sites.

One psyllid collected last week in Canyon County tested positive for Lso (liberibacter), the bacterium that causes zebra chip.


June 29, 2018

Psyllid abundance remains relatively low

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (six fields), Owyhee (one field) and Twin Falls (two fields).

This week, we collected 16 psyllids from sticky cards (eight light sites and one intense site). 

We had traps deployed in 85 of the estimated 97 fields (87 percent) that will be monitored this year and found psyllids in 9 of the monitored fields (10.5 percent). However, we are still waiting to receive cards from four sites.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.

Thus far, psyllid abundance has been relatively low this year; however, potato psyllid abundance typically increases during July through August.


June 22, 2018

A few more psyllids found in Treasure and Magic Valleys

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (three fields), Jerome (one field) and Twin Falls (one field).

This week, we collected 10 psyllid from sticky cards (three light sites and two intense sites).

We had traps deployed in 85 of the estimated 97 fields (87 percent) that will be monitored this year and found psyllids in five of the monitored fields (5.8 percent). However, we are still waiting to receive cards from 19 sites.

All psyllids collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.


June 15, 2018

First potato psyllid found in Magic Valley

Psyllids were collected this week on sticky traps in potato in the following counties: Canyon (three fields), Owyhee (one field) and Twin Falls (one field).

This week, we collected six psyllid from sticky cards (five light sites).

We had traps deployed in 75 of the estimated 85 fields (88 percent) that will be monitored this year and found psyllids in five of the monitored fields (5.8 percent).

The psyllid collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.


June 8, 2018

Another psyllid found in Treasure Valley; none in Magic Valley

One potato psyllid was collected on a sticky trap in potato in the following county: Canyon (one field).

This week, we collected one psyllid from sticky cards (one light site).

We had traps deployed in 50 of the estimated 89 fields (56 percent) that will be monitored this year and found one psyllid in one of the monitored fields (2 percent).

The psyllid collected last week tested negative for Lso (liberibacter), the bacterium that causes zebra chip.


June 1, 2018

First potato psyllid found in Idaho potato fields this season

One potato psyllid was collected on a sticky trap in potato in the following county: Canyon (one field).

This week, we collected one psyllid from sticky cards (one light site).

We had traps deployed in 50 of the estimated 88 fields (57 percent) that will be monitored this year and found one psyllid in one of the monitored fields (1.13 percent).


2018 Potato psyllid monitoring program underway in Idaho

The University of Idaho, in collaboration with Miller Research and several crop consultants across the state will continue our monitoring program for potato psyllids, zebra chip and liberibacter (Lso), the bacterium that causes zebra chip. The monitoring program covers commercial potato fields throughout southern Idaho and currently is funded in part by USDA and generous in-kind contributions by our collaborators.

The first deployment of sticky cards occurred last week in 17 Treasure Valley sites and 21 Magic Valley sites. Next week we expect to initiate sampling in eight and 17 additional fields in the treasure and magic valleys, respectively.

This week we collected our first sticky cards of the season from potato fields. No potato psyllids were found in potato fields this week.

More details on the program will be forthcoming as we continue to ramp up sampling efforts. We hope to maintain a monitoring program at a level similar to recent years, but the breadth of the program this year will depend on funding that is still pending.


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Contact

College of Agricultural & Life Sciences

Physical Address:
E. J. Iddings Agricultural Science Laboratory
606 S Rayburn St

Mailing Address:
875 Perimeter Drive MS 2331
Moscow, ID 83844-2331

Phone: 208-885-6681

Fax: 208-885-6654

Email: ag@uidaho.edu

Web: uidaho.edu/cals/potatoes

Location

Mailing Address:
1693 S 2700 W
Aberdeen, ID 83210

Phone: 208-397-4181

Fax: 208-397-4311

Web: uidaho.edu/cals/aberdeen

Location

Mailing Address:
3793 North 3600 East
Kimberly ID 83341-5076

Phone: 208-423-4691

Fax: 208-423-6699

Web: uidaho.edu/cals/kimberly

Location

Mailing Address:
29603 U of I Lane
Parma, ID 83660-6699

Phone: 208-722-6701

Fax: 208-722-6708

Web: uidaho.edu/cals/parma

Location