Progress 07/01/05 to 06/30/11
Outputs
OUTPUTS: Some promising fungicide combinations for sweet corn seed treatment were identified. Several field spray studiesconducted with a wide range of fungicides for control of neck rot of onions in storage did not indicate any field spray program that was consistently efficient in providing significant control. Iris yellow spot virus is endemic in onion fields, with the incidence and severity varying from year to year and depending on the onion cultivar and the location of the field in relation to the overwintering inoculum (infected onion seed field). Sequence diversity of the nucleoprotein gene of IYSV was described. Onion varieties with differing degrees of symptom expression to IYSV were identified. Several weed hosts (redroot pigweed, puncturevine, kochia, prickly lettuce, common labsquarters) were identified as reservoirs of IYSV in the Treasure Valley. The powdery mildew Leveillula taurica was documented infecting several commercial onion varieties, and some ornamental perennial hosts (Cleome hassleriana, Mentzelia laevicaulis) of this fungus in the Treasure Valley region were identified. A rust (Puccinia similis) disease of Artemisia tridentata, a virus (cucumber mosaic virus) disease of Pestemon acuminatus, and a bacterial (Pseudomonas syringae) cane blight of rose, all new disease records to this region, were documented. All these significant ouputs were presented at the commodity and professional meetings (commodity commissions, conferences, workshops, grower meetings, American Phytopathological Society meetings, etc.)and published in peer-reviewed professional journals (Plant Disease, HortTechnology, etc.). PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Target audiences: Master gardeners, growers, homeowners, county extension educators, researchers, fieldmen, crop advisors, pesticide company representatives. Efforts: Presentations, classroom teaching, publications. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The project results helped sweet corn seed companies and sweet corn producers to choose the most effective seed treatment for different sweet corn cultivars and the growing regions, with the best treatment in most cases resulting in more than 100% increase in final stand compared to the untreated check. The multi-location seed treatment trial results provided the basis for obtaining necessary registration for use of some fungicides like Maxim and Dividend by the sweet corn seed industry. Documentaion and dissemination of information on Iris yellow spot virus and powdery mildew as new diseases of onion helped onion industry in making some production changes to minimize the impact of these diseases. Ineffectiveness of field fungicide sprays in controlling neck rot in storage demonstrated in this project helped onion growers save significant resources and prevent unnecessary use of fungicides in the region. Identification of new reservoirs of inoculum in the region for IYSV and powdery mildew of onion has contributed for better understanding of the epidemiology and management of these diseases. Identification of bacterial cane blight of roses as a distinct disease, different from winter/cold/frost damage, has led to effective disease management practices to reduce losses.
Publications
- No publications reported this period
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: For identifying effective fungicides for control of neck rot of onion, four spray treatments were studied in a field experiment during the 2009 growing season and the harvested bulbs were stored and evaluated during January 2010 for neck rot incidence. A report of the results was provided to the sponsoring companies. During the onion harvest period of fall 2010, 25 onion bulb samples representing different varieties were collected and put in storage for evaluation of neck rot incidence at the end of February 2011 and these samples will be included in a collaborative study with the University of Georgia for characterization of volatiles emitted by the rotting bulbs. Collaborated in a project to evaluate the effect of selected cultural practices in suppressing Iris Yellow Spot disease in onion. In a multi-location cooperative trial, 28 seed treatments were evaluated on one seed lot of sweet corn hybrid Super Sweet Jubilee. Stand data from 13 locations were tabulated, analyzed, summarized and presented to the sweet corn seed and processing industry representatives and growers. Monitored four bean sentinel plots in southern Idaho for pests and diseases, including soybean rust and soybean aphid. A bacterial cane blight disease of rose occurring in Idaho was characterized and reported. Documented for the first time in the literature the occurrence of rust caused by Puccinia similis on sagebrush (Artemesia tridentata) in Idaho and Oregon. The results of a collaborative project on management of powdery mildew in table grapes was disseminated to the grape growers in the form of a video/multi-media CD. Processed about 150 plant samples submitted for disease diagnosis, and communicated the results and management guidelines to the clientele. Presented information on various aspects of plant diseases, causes, management and diagnosis through courses and meetings to the master gardeners, fieldmen and growers. A presentation on the risk soybean growing poses to bean seed industry in the state was made to the seed industry representatives. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Target audiences: Master gardeners, growers, researchers, field and pesticide company representatives, county extension educators. Efforts: Presentations and classes on diseases of different plants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results of onion fungicide evaluations showed that field application of fungicide sprays do not control neck rot of onions in storage. Certain cultural practices appeared to reduce IYSV symptom severity in the field. Several seed treatment mixtures were effective in increasing the final field stand of sweet corn. The organic/biological treatments did not show high level of efficacy. These results are of immediate practical application by the sweet corn growers and seed industry. Disease diagnostic services provided information that could be used by the growers to take timely measures of disease prevention and control leading to rational use of pesticides. The disease diagnostic data uploaded to WPDN/NPDN and Legume PIPE databases is being used by various regulatory and commodity agencies. Publication of new disease records on sagebrush rust, and bacterial cane blight of rose is helpful for growers, diagnosticians, extension agents and plant pathologists to identify the disease problems and adopt suitable management practices.
Publications
- Mohan, S.K., and Bijman, V.P. 2010. Bacterial cane blight of rose caused by Pseudomonas syringae. Acta Horticulturae 870:109-113.
- Sampangi, R.K., Aime, M.C., and Mohan, S.K. 2010. First report of rust caused by Puccinia similis on Artemisia tridentata in Idaho and Oregon. Plant Dis. 94:380.
- Agenbroad, A.M., Meds, M., McCammon, T., Mohan, S.K., and Fallahi, E. 2010. Preventing powdery mildew in table grapes: A multi-faceted, organic approach for Idaho. A video/multimedia CD produced by University of Idaho Extension, Canyon County, Caldwell, ID.
- Shock, C., Feibert, E.B.G., Saunders, L.D. Jensen, L.B., Pappu, H.R., Mohan, S.K., and Sampangi, R.K. 2009. Cultural practices to reduce the expression of Iris Yellow Spot Virus. American Society of Horticultural Sciences Annual Conference, 25-28 July 2009, St. Louis, Missouri (Abstract)
- Shock, C., Feibert, E.B.G., Saunders, L.D. Jensen, L.B., Pappu, H.R., Mohan, S.K., and Sampangi, R.K. 2009. Effect of selected cultural practices in suppressing Iris yellow spot virus in onion. IX International Symposium on Thysanoptera and Tospoviruses, 31 August-4 September, 2009, Sea World Resort, Gold Coast, Queensland, Australia (Poster/Abstract.
- Shock, C., Feibert, E.B.G., Saunders, L.D. Jensen, L.B., Mohan, S.K., and Pappu, H.R. 2009. 2008 Onion variety trials. Oregon State University AES, Special Report 1094:20-28. http://www.cropinfo.net/AnnualReports/2008/2008OnionVarietyTrials.htm l
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Onion bulbs in storage from the field experiment conducted during 2008 growing season with six spray treatments were evaluated for neck rot incidence in February 2009. A field experiment with six spray treatments was conducted in the summer of 2009 for evaluation of fungicides for control of onion neck rot in storage, and the harvested bulbs are being held in storage for evaluation during February 2010. Samples from weed and crop plants in the vicinity of onion fields are collected and are being analyzed for the presence IYSV both in the shoot and root portions. The effect of selected cultural practices on suppressing IYSV in onion is being studied in collaboration with the Oregon State University. Incidence (natural) and severity of powdery mildew caused by Leveillula taurica on onion varieties was documented. Crops, weeds and other plants in the region were surveyed to identify the source(s) of primary inoculum of L. taurica on onion. The results of onion powdery mildew and IYSV studies were presented at the annual meeting of the Regional Project W-1008. A multi-location sweet corn seed treatment trial with 28 treatments was conducted, and the results from 17 locations in the U.S. and one from Japan were presented to the sweet corn research, seed and processing industry group at the annual meeting of the Regional Project NECC1008. Erwinia amylovora cultures obtained from raspberry were inoculated on to apple, pear, plum and raspberry shoots for pathogenicity tests. In a collaborative study with USDA/ARS scientists, 15 E. amylovora isolates from different hosts and locations were analyzed for the presence of the plasmid pEA29. About 180 plant samples were processed for disease identification and the results communicated to the respective clients and uploaded to the Western Plant Diagnostic Network website. Diseases and pests were monitored in four bean sentinel plots through periodic sampling, and the results were uploaded to Legume PIPE and WPDN databases. Information on a bacterial cane blight of rose caused by Pseudomonas syringae was presented to the research and grower community at the International Symposium on Rose Research, held in Gifu, Japan. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The results of fungicide spray on neck rot incidence in stored onions showed that none of the currently available products is effective. Onion varieties with less IYSV and powdery mildew symptom severity were identified, and certain cultural practices appear to reduce IYSV disease severity in the field. The giant blazing star (Mentzelia laevicaulis) was found to be infected with L. taurica powdery mildew, a first record of this host-pathogen association. Many of the seed treatments improved the sweet corn stand by more than 100% compared to the untreated control. Treatments with polymer coating and nutrient enhancements, and organic seed treatments performed well in many locations. These results are of immediate practical use by the sweet corn growers and seed industry. The E. amylovora strain from raspberry was found to be pathogenic to apple, pear and plum as well. Of the 15 strains of E. amylovora examined, five were found to lack the plasmid pEA29. Timely disease diagnosis/identification helped the growers to adopt appropriate preventive/control measures and adopt rational use of pesticides. The information on disease occurrence in various plants/crops uploaded to WPDN and Legume PIPE databases was used by the various regulatory and commodity agencies. Identification of distinctive symptoms of bacterial cane blight and its etiology have helped rose growers with effective management of this disease in their operations.
Publications
- Sampangi, R.K., Almeyda, C., Druffel, K.L., Mohan, S.K., Shock, C.C., and Pappu, H.R. 2009. First report of natural infection of Penstemon acuminatus with Cucumber mosaic virus in the Treasure Valley region of Idaho and Oregon. Plant Dis.93,762.
- Sampangi, R.K., Glawe, D.A., Barlow, T. and Mohan, S.K. 2010. First report of powdery mildew caused by Leveillula taurica on giant blazing star (Mentzelia laevicaulis). Plant Dis.94,132.
- Mohan, S.K. and Bijman, V.P. 2010. Bacterial cane blight of rose caused by Pseudomonas syringae. Acta Horticulturae.(Symposium Proceedings; In press.
- Sampangi, R.K., Aime, M.C., Mohan, S.K.. 2010. First report of rust caused by Puccinia similis on Artemisia tridentata in Idaho and Oregon. Plant Dis. In press.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Onion bulbs stored from a field experiment conducted in 2007 with 11 fungicide treatments (field sprays) for control of onion neck rot were evaluated in February 2008. During the 2008 growing season, the field experiment involved six treatments and the harvested bulbs are being held in storage for evaluation of neck rot incidence in February 2009. Field surveys were conducted for identification of non-onion hosts for Iris yellow spot virus. Onion varieties, other commonly grown crops, ornamentals and weeds were surveyed for incidence of powdery mildew caused by Leveillula taurica. The results were presented at the grower meetings and through publications. A multi-location field trial with 13 treatments and two sweet corn varieties was conducted with 17 cooperators across the U.S., and one from Japan. A summary of these results were presented to the sweet corn research, seed and processing industry/community at the annual meeting of the Regional Project. A case of blossom and shoot blight of raspberry caused by Erwinia amylovora was documented from southeastern Idaho. The pathogen was isolated and appropriate bacteriological and pathogenicity tests are in progress. Approximately 200 plant samples were processed for disease identification and the results uploaded to the Western Plant Diagnostic Network. Approximately 50 samples of legumes (soybean, bean, peas) were analyzed for soybean rust, soybean aphid, and other diseases and pests. The results were uploaded to WPDN database. PARTICIPANTS: S.K. Mohan, Principal Investigator; R.K. Sampangi, Extension Support Scientist; S. Keith, Temporary Help. The Research Support Scientist position, included under Personnel in this project approved by CSREES as required for its implementation, was not provided. Idaho State Department of Agriculture, Boise, ID; Malheur Experiment Station, Oregon State University, Ontario, OR; Cooperative Extension System, University of Idaho; International Sweet Corn Development Association; Washington State University, Pullman, WA. TARGET AUDIENCES: Master Gardeners: Classes (Caldwell, Boise) on 'Plant Diseases and Disease Identification.' Growers: Presentation on 'Iris yellow spot virus' to growers during the Malheur Experiment Station, OSU, Ontario Field Day. Presentation on 'sweet Corn Seed Treatments' during the Vegetable Field Tour, Parma R & E Center. Presentation on 'Powdery mildew, a New Disease on Onion' to Idaho & Malheur County Onion Growers' Association. Presentation on 'Major disease problems of tree fruits (peach, cherries, apples)' to growers in Emmett, ID. Presentation on 'Role of plant health clinic in mitigating plant diseases in Idaho'to the participants of the International Congress of Plant Pathology, Evening Session # 17, Torino, Italy. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Due to the optimum conditions during the 2007 growing and harvesting periods, there were no differences among treatments for neck rot incidence after 4 months in storage. There were no significant differences in the total yield among six fungicide spray treatments examined during 2008. Contributed as author/co-author of 10 chapters on onion diseases, and co-edited the Compendium of Onion and Garlic Diseases and Pests. Powdery mildew (Leveillula taurica) was observed on a few onion varieties, and several new hosts of this fungus, including penstemon and globe mallow, in the region were identified.The sweet corn seed treatment trial indicated that the variety Super Sweet Jubilee Plus produced less stand than the variety Incredible at all the 13 locations. Treatment mixtures containing Tops 30 performed similar to the standard treatmen mixtures in both the varieties. Organic or conventional seed enhancement treatments showed modest increase in stand compared to untreated check, but were less effective than the standard fungicide treatments, in most locations in both the varieties. Identification of Erwinia amylovora infecting raspberry in Idaho constitutes the first record of this disease in the Pacific Northwest. Training in plant disease identification was proded to county extension educators and master gardeners through classes organized in southwest Idaho. Monitoring of bean, pea and soybean crops for diseases and pests during the year confirmed the absence of sobean rust and soybean aphid in this region.
Publications
- Sampangi, R.K. and Mohan, S.K. 2008. Symptoms of co-infection of Iris yellow spot virus (IYSV) and downy mildew on onion scapes (flower stalks). APSnet Featured Image. http://www.apsnet.org/online/iwreview/iw000105.asp
- Sampangi, R., Mohan, S.K., Shock, C.C., Feibert, E.B.G. and Glawe, D.A. 2008. Powdery mildew of onion caused by Leveillula taurica and the possible epidemiological role of alternative hosts in Idaho and Oregon. Phytopathology 98:S139.
- Sampangi, R.K., Mohan, S.K., Shock, C.C., Feibert, E.B.G. and Glawe, D.A. 2008. Powdery mildew (Leveillula taurica) incidence on onion cultivars and some native flowering plants in the Treasure Valley region of Idaho and Oregon. In Proc. 2008 National Allium Research Conference, Savannah, GA, p. 15.
- Sampangi, R.K., Mohan, S.K., Shock, C.C. and Feibert, E.B.G. 2008. Abundance and population dynamics of onion thrips and incidence of Iris yellow spot virus in Treasure Valley region of Idaho and Oregon. In Proc. 2008 National Allium Research Conference, Savannah, GA, p. 25.
- Shock, C., Feibert, E., Saunders, L. and Mohan, K. 2008. Onion variety response to Iris yellow spot virus. Page 27 to 28 in Proc. 2008 National Allium Research Conference, Savannah, GA, pp. 27-28.
- Schwartz, H.F. and Mohan, S.K. 2008 (Editors). Compendium of Onion and Garlic Diseases and Pests. APS Press, St. Paul, MN. 127 pp.
- Mohan, S.K. 2008. Author/co-author of 10 Chapters (Introduction: pages 1-7; Scape Blight of Onion: pages 29-30; Flower and Capsule Blight of Onion: page 30; Brown Stain of Onion: page 49; Other Botrytis Rots: pages 49-50; Diseases Caused by Bacteria and Yeast: pages 55-58; Soft Rots: pages 59-62; Other Bacterial Soft Rots: pages 62-63; Slippery Skin: page 63; Other Bacterial Diseases: page 68) in the Compendium of Onion and Garlic Diseases and Pests (Schwartz, H.F. and Mohan, S.K., Editors), APS Press, St. Paul, MN. 127 pp.
- Shock, C.C., Feibert, E., Jensen, L., Mohan, S.K. and Saunders, L.D. 2008. Onion variety response to Iris yellow spot virus. HortTechnology 18:325-344.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Onion bulbs from the 2006 field trial with 10 fungicide sprays were evaluated for neck rot incidence after 4 months of storage. Eleven treatments were evaluated on onions in the field during 2007 for their effect on total yield and incidence of storage rots. This information is disseminated to the onion growers and technical advisors. Over 175 samples from 35 plant species were analyzed for Iris yellow spot virus using ELISA and RT-PCR. In a field trial, 54 onion varietes were evaluated for incidence and severity of Iris yellow spot virus and powdery mildew. This information is provided to the onion growers through annual reports. Several crops, weeds and other plants in the vicinity of onion fields were examined for occurrence of powdery mildew caused by Leveillula taurica. This information is disseminated through publication in a professional journal. A multi-location trial with 15 seed treatments and two sweet corn varieties was conducted in 15 locations in the U.S., one
in Argentina and one in Japan. This information was presented to sweet corn research community and industry at the annual meeting of the Regional Project. Erwinia amylovora isolates established from Pluot cv. Dapple Dandy and European plum cv. Empress have been further characterized. Part of the results are presented at the International Fire Blight Workshop. Over 150 samples submitted by clients were processed for disease identification and the results are uploaded to the Western Plant Diagnostic Network. Legume samples (dry bean, garden bean, soybean, peas) were processed as part of Pest Information Plantform for Extension and Education (PIPE).
PARTICIPANTS: S. K. Mohan, Principal Investigator
TARGET AUDIENCES: Master Gardeners: Classes on Plant Diseases and Disease Identification Growers: Seminars on Onion, Sweet Corn, Apple, and Diseases and their management. Researchers: Presentations in professional meetings (American Phytopathological Society, International Plant Virus Epidemiology Symposium, International Workshop on Fire Blight)
Impacts
From the 2006 fungicide evaluation, neck rot incidence in onion bulbs, after 3 1/2 storage, ranged from 22 to 35% but the differences between the treatments were not significant. No significant differences in total yield of onion bulbs was found in the 2007 trial. Of the more than 175 samples of onions, weeds, other crops and plants tested, Iris yellow spot virus was confirmed in volunteer onions, redroot pigweed, puncturevine, kochia, prickly lettuce and common lambsquarters. Onion varieties (54) did not show significant natural incidence of Iris yellow spot virus in the field. Out of the 54 varieties evaluated, 23 were found infected with powdery mildew caused by Leveillula taurica. Spiderflower (Cleome hassleriana; pink queen) plants in the vicinity of onion fields were found infected with L. taurica including its teleomorph, a first North American record. Treatment mixtures containing Vortex, Trilex, Tops 30 performed similar to the standard sweet corn seed
treatments. Bacterial cultures from shoot blight samples from pluot and European plum were identified as Erwinia amylovora, a new world record. Training in plant disease identification was provided to county agents and master gardeners through several classes organized in southwest Idaho. Participated in a 'Select Agent Exercise' for the State of Idaho using plum pox as the 'Pest of Concern', organized by the National Plant Diagnostic Network. Monitoring of bean crop for incidence of pests and diseases throughout the season through PIPE has resulted in detection of incidence of Bean Common Mosaic Virus and Curly Top Virus in some fields. The Research Support Scientist position (included under Personnel in this project approved by CSREES as required for its implementation), was not provided.
Publications
- Sampangi, R., Glawe, D.A. and Mohan, S.K. 2007. First North American record of powdery mildew of Cleome hassleriana caused by Leveillula taurica. Plant Health Progress doi:10.1094/PHP-2007-0219-02-BR.
- Sampangi, R.K., Mohan, S.K. and Pappu, H.R. 2007. Identification of new alternative weed hosts for Iris yellow spot virus in the Pacific Northwest. Plant Dis. 91:1683.
- Gent, D.H., du Toit, L.J., Mohan, S.K., Pappu, H.R. and Schwartz, H.F. 2007. Emergence of Iris yellow spot virus in the western U.S. Phytopathology 97:S167.
- Pappu, H.R., Sampangi, R., Mohan, S.K., Schwartz, H.F. and Rondon, S.I. 2007. Thrips-transmitted Iris yellow spot tospovirus epidemics in the US: Progress and challenges in unraveling the epidemiological factors underlying the disease outbreaks in onion seed and bulb crops. 10th International Plant Virus Epidemiology Symposium, 15-19 October, 2007, ICRISAT, Patancheru 502324, A.P., India. Keynote Presentation. Page 29.
- Mohan, S.K. 2007. Natural incidence of shoot blight in Pluot caused by Erwinia amylovora. 11th International Workshop on Fire Blight, 12-17 August 2007,Portland, OR. Abstract # O52, page 64.
- Sampangi, R., Druffel, K., Mohan, K. and Pappu, H. 2007. New weed hosts for Iris yellow spot virus. Phytopathology 97:S103.
- Mohan, S.K. 2006. Fire Blight: Biology and Management. Proceedings of the 12th Simposium Internacional 2006 Sobre el Manzano, Cd. Cuauhtemoc, Chihuahua, Mexico, November 10, 2006. 7 pp.
- Mohan, S.K. 2006. Fungal Diseases of Apple: Powdery Mildew and Collar Rot. Proceedings of the 12th Simposium Internacional 2006 Sobre el Manzano, Cd. Cuauhtemoc, Chihuahua, Mexico, November 10, 2006. 6 pp.
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Progress 01/01/06 to 12/31/06
Outputs
Evaluation of nine fungicides as sprays on onion crop during growing season, showed that Scala, Botran, Elevate and Quadris reduced incidence of neck rot of bulbs following 3 months of ambient storage. If bulbs were stored without adequate field curing, none of the treatments was effective. Several weeds commonly occurring in onion fields are being tested as potential reservoirs of Iris Yellow Spot Virus (IYSV). Forty six onion varieties were evaluated for severity of IYSV symptoms under conditions of natural incidence. Powdery mildew caused by Leveillula taurica was observed infecting 4 out 46 varieties of onion in a field trial. The ornamental plant Cleome hassleriana, in the vicinity of the onion field, was found infected with L. taurica. Thirteen seed treatmens were evaluated on two sweet corn hybrids at 18 locations. The standard treatments Captan + Thiram + Allegiance, or Apron + Maxim + Dividend resulted in superior and consistent performance compared to the
two biological/organic treatments. Over 260 plant samples were analyzed in the disease diagnostic laboratory. Dry edible bean and soybean plant samples were examined for incidence of soybean rust and soybean aphid, and other diseases.
Impacts
Fungicide field sprays for control of neck rot of onions in storage identified in this project will reduce storage losses to the onion industry. Identification of onion varieties less susceptible to Iris Yellow Spot will help growers to implement integrated disease management strategies.
Publications
- Gent, D.H., du Toit, L.J., Fichtner, S.F., Mohan, S.K., Pappu, H.R. and Schwartz, H.F. 2006. Iris yellow spot virus: An Emerging Threat to Onion Bulb and Seed Production. Plant Dis. 90:1468-1480.
- Pappu, H.R., du Toit, L.J., Schwartz, H.F. and Mohan, K. 2006. Sequence diversity of the nucleoprotein gene of Iris yellow spot virus (genus Tospovirus, family Bunyaviridae) isolates from the western region of the United States. Archives of Virology 151:1015-1023.
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Progress 01/01/05 to 12/31/05
Outputs
A field experiment for control of neck rot was conducted with nine fungicide treatments. No significant yield differences were detected at harvest, and the bulbs are being maintained in ambient storage to be evaluated in January 2006 for neck rot incidence. Several onion fields in the Treasure Valley region were found with high severity of Iris yellow spot disease. Twenty isolates of Erwinia amylovora from apple and pear orchards in the Treasure Valley were established for verification of their streptomycin sensitivity.
Impacts
Effective control measures for neck rot of onion will reduce losses to the onion growers and packers. Knowledge about streptomycin sensitivity of the fire blight pathogen in the orchards will help growers better manage this destructive disease.
Publications
- No publications reported this period
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