GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    A Survey of Plant-Parasitic Nematodes in Illinois Corn Fields, 2018 and 2020
    Scientific Societies ; 2021
    In:  Plant Health Progress Vol. 22, No. 4 ( 2021-01-01), p. 560-564
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 22, No. 4 ( 2021-01-01), p. 560-564
    Abstract: One hundred forty-seven soil samples were collected from corn fields located within 63 Illinois counties during the 2018 and 2020 corn growing seasons. The soil samples were analyzed for frequency and population density of plant-parasitic nematodes. A total of 10 plant-parasitic nematode taxa were identified. Spiral nematode (Helicotylenchus spp.) was the most frequently observed nematode (frequency: 98.6%), followed by lesion nematode (Pratylenchus spp., 85.7%). Other taxa identified included cyst (Heteroderidae, 66.7%), stunt (Tylenchorhynchus spp., 33.3%), lance (Hoplolaimus spp., 29.9%), dagger (Xiphinema spp., 12.9%), pin (Paratylenchus spp., 12.2%), needle (Longidorus spp., 1.4%), stubby-root (Trichodoridae, 1.4%), and ring nematodes (Criconematidae, 0.7%). Nematodes with the greatest population densities included spiral (89 nematodes per 100 cm 3 of soil), pin (36), and cyst nematodes (26). Among the 10 nematode taxa, 4.1, 7.1, and 2.3% of spiral, lesion, and lance nematode-positive samples exceeded estimated damage thresholds for corn for Illinois, respectively. Results from this survey will help the agricultural community with understanding pathogenic corn nematode populations in the state and prioritize research in this understudied area.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-01-21-0012-S
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2021
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Documenting the Establishment, Spread, and Severity of Phyllachora maydis on Corn, in the United States
    Oxford University Press (OUP) ; 2020
    In:  Journal of Integrated Pest Management Vol. 11, No. 1 ( 2020-01-01)
    Details
    In: Journal of Integrated Pest Management, Oxford University Press (OUP), Vol. 11, No. 1 ( 2020-01-01)
    Abstract: Tar spot on corn, caused by the fungus (Phyllachora maydis Maubl. [Phyllachorales: Phyllachoraceae]), is an emerging disease in the United States. In 2018 and 2019, significant but localized epidemics of tar spot occurred across the major corn producing region of the Midwest. After being first detected in 2015, tar spot was detected in 135 and 139 counties where the disease was not previously detected in 2018 and 2019, respectively, and is now established across 310 counties across the United Sates. Foliage with signs (stromata) of P. maydis and symptoms of tar spot were collected from 128 fields in 2018 and 191 fields in 2019, across seven states. Samples were assessed for severity of fungal stromata (percent leaf area covered with stromata) on foliage and the incidence of fisheye lesions (proportion of lesions with fisheye symptoms) associated with fungal stromata. Stromatal severity on samples in 2018 ranged from 0.5 to 67% and incidence of fisheye lesions ranged from 0 to 12%, whereas in 2019, stromatal severity ranged from 0.1 to 35% and incidence of fisheye lesions ranged from 0 to 80%, with 95% of samples presenting less than 6% incidence of fisheye lesions. Tar spot has spread substantially from where it was first reported in the United States. Collaborative efforts to monitor the spread and educate clientele on management are essential as this disease spreads into new areas.
    Type of Medium: Online Resource
    ISSN: 2155-7470
    URL: Article
    DOI: 10.1093/jipm/pmaa012
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2020
    detail.hit.zdb_id: 2607369-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Effects of fluopyram on Pratylenchus penetrans on corn in the field and in vitro
    Scientific Societies ; 2023
    In:  Plant Disease
    Details
    In: Plant Disease, Scientific Societies
    Abstract: The effects of a fluopyram seed treatment on lesion nematodes (Pratylenchus spp.) and other plant-parasitic nematodes (PPNs) were evaluated on corn in multiple field locations in 2020 and 2021. The highest rate of fluopyram seed treatment (0.15 mg seed -1 ) reduced early season population density of lesion nematodes, compared to the base treatment control in 2020 only. However, fluopyram did not affect late season lesion nematode population density and corn yields. Fluopyram seed treatment also had minimal or non-significant effects on other PPN species. Based on these results, the effects of fluopyram were tested in vitro on P. penetrans. Results demonstrated that fluopyram severely affected motility in P. penetrans. The sensitivity of P. penetrans J2s to fluopyram was significantly higher than at J4 and adult, suggesting that sensitivity to fluopyram is dependent on developmental stage. In addition, the effects of fluopyram were reversible at an EC50 but were irreversible at the maximum concentration (25 µg/ml). Overall, our results indicate that fluopyram has potential for controlling P. penetrans, but its efficacy is variable depending on nematode developmental stage and chemical concentration. Further research is needed to determine if these impacts can translate to field scenarios.
    Type of Medium: Online Resource
    ISSN: 0191-2917 , 1943-7692
    URL: Article
    DOI: 10.1094/PDIS-04-23-0725-RE
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2023
    detail.hit.zdb_id: 2042679-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Uncovering the environmental conditions required for Phyllachora maydis infection and tar spot development on corn in the United States for use as predictive models for future epidemics
    Springer Science and Business Media LLC ; 2023
    In:  Scientific Reports Vol. 13, No. 1 ( 2023-10-10)
    Details
    In: Scientific Reports, Springer Science and Business Media LLC, Vol. 13, No. 1 ( 2023-10-10)
    Abstract: Phyllachora maydis is a fungal pathogen causing tar spot of corn ( Zea mays L.), a new and emerging, yield-limiting disease in the United States. Since being first reported in Illinois and Indiana in 2015, P. maydis can now be found across much of the corn growing regions of the United States. Knowledge of the epidemiology of P. maydis is limited but could be useful in developing tar spot prediction tools. The research presented here aims to elucidate the environmental conditions necessary for the development of tar spot in the field and the creation of predictive models to anticipate future tar spot epidemics. Extended periods (30-day windowpanes) of moderate mean ambient temperature (18–23 °C) were most significant for explaining the development of tar spot. Shorter periods (14- to 21-day windowpanes) of moisture (relative humidity, dew point, number of hours with predicted leaf wetness) were negatively correlated with tar spot development. These weather variables were used to develop multiple logistic regression models, an ensembled model, and two machine learning models for the prediction of tar spot development. This work has improved the understanding of P. maydis epidemiology and provided the foundation for the development of a predictive tool for anticipating future tar spot epidemics.
    Type of Medium: Online Resource
    ISSN: 2045-2322
    URL: Article
    DOI: 10.1038/s41598-023-44338-6
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2023
    detail.hit.zdb_id: 2615211-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Prevalence and Cropping System Impacts on Soybean Vein Necrosis Disease in Delaware Soybeans
    Scientific Societies ; 2018
    In:  Plant Health Progress Vol. 19, No. 1 ( 2018-01-01), p. 11-12
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 19, No. 1 ( 2018-01-01), p. 11-12
    Abstract: Soybean vein necrosis disease (SVN) is the most widespread virus of soybeans in the United States. This thrip-vetcored virus can cause foliar chlorosis and necrosis, and it can reduce soybean oil content, which may impact producers of high-oleic acid soybeans in the mid-Atlantic. The prevalence of SVN in Delaware is unknown. In addition, we hypothesized that cropping system (i.e., full-season versus double-cropped) beans may differ in SVN, likely owing to duration of exposure to viruliferous thrips. SVN incidence was assessed in 88 soybean fields (48 full season, 40 double crop following small grains) from 2015 to 2017. Each field was assessed at the vegetative growth stage and early reproductive stage. Following statistical analysis using a random mixed repeated measures model, data indicated that SVN incidence increased from 4.5 to 29.8% when comparing vegetative versus reproductive growth stages. SVN incidence was 50% lower in full-season compared with double-cropped soybeans. Our data indicate that double-cropped soybeans or late-planted soybeans may be at higher risk for SVN, and therefore producers of high-oleic acid soybeans should avoid late planting dates.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-09-17-0055-BR
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2018
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Fungicide Resistance Management Guidelines for Cucurbit Downy and Powdery Mildew Control in the Mid-Atlantic and Northeast Regions of the United States in 2018
    Scientific Societies ; 2018
    In:  Plant Health Progress Vol. 19, No. 1 ( 2018-01-01), p. 34-36
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 19, No. 1 ( 2018-01-01), p. 34-36
    Abstract: In the mid-Atlantic and Northeast regions of the United States, more than 163,000 acres of fresh-market vegetable crops are grown annually. Two important diseases of cucurbit crops across the Unites States and world are powdery mildew caused by Podosphaera xanthii (formerly Sphaerotheca fuliginea [Schlecht ex Fr.] Poll.) and downy mildew caused by Pseudoperonospora cubensis. Resistance to a number of high-risk fungicides has been detected in both pathogens. To help cucurbit growers in the mid-Atlantic and Northeast regions properly manage both diseases, an updated fungicide resistance management table has been developed to promote the importance of understanding Fungicide Resistance Action Committee (FRAC) codes. This table provides a tool to allow cucurbit growers to develop season-long cucurbit downy and powdery mildew control programs.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-12-17-0077-BR
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2018
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Phyllachora maydis Ascospore Release and Germination from Overwintered Corn Residue
    Scientific Societies ; 2020
    In:  Plant Health Progress Vol. 21, No. 1 ( 2020-01-01), p. 26-30
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 21, No. 1 ( 2020-01-01), p. 26-30
    Abstract: Tar spot of corn, caused by Phyllachora maydis, has been reported in several upper Midwest states in the United States. This has led to expanded efforts to more thoroughly understand the biology of P. maydis and the epidemiology of tar spot. This study determined the potential for P. maydis ascospore release and germination from overwintered P. maydis-infected corn residues from various locations in the upper Midwest. Corn residue samples collected in the spring of 2019 from 12 fields in four states were examined. Ascospore release and germination were observed in all residue samples collected. The mean total number of ascospores released per milliliter of water ranged from 3.6 × 10 3 to 4.8 × 10 6 after 4-h incubation and 3.7 × 10 3 to 4.4 × 10 6 after 24-h incubation. The mean percent spore germination ranged from 0.7 to 24.1% after 4-h incubation and 2.4 to 24.9% after 24-h incubation. There was a significant inverse relationship between total numbers of ascospores released and the percent germination of the ascospores. Samples from Illinois consistently yielded the greatest total ascospore release but were also consistently among the samples with the lowest percent ascospore germination. Samples from Wisconsin and Indiana were among the lowest for total ascospore numbers but were among the highest for total ascospore germination. These findings provide evidence that P. maydis can overwinter in multiple areas of the upper Midwest. Future research should focus on reducing infested corn residue to reduce initial infection by P. maydis.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-10-19-0077-RS
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2020
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    An Observation of Corn Tar Spot Dispersal from Agricultural Fields to an Isolated Urban Plot
    Scientific Societies ; 2021
    In:  Plant Health Progress Vol. 22, No. 1 ( 2021-01-01), p. 69-71
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 22, No. 1 ( 2021-01-01), p. 69-71
    Abstract: Tar spot of corn is a fairly new disease to the United States, and since its introduction in 2015 it has spread to over 310 counties across nine states. Little is understood of the biology and epidemiology of the causative agent of tar spot of corn, Phyllachora maydis. Published research from Latin America indicates that spores can only travel a distance of 75 m; however, rapid progression and spread in the United States, in addition to widespread observations of top-down infection, indicate distal dispersal is likely more important. We observed an isolated plot of decorative corn in an urban setting, isolated from agricultural fields. We assessed nearby fields for crop, tar spot, cropping history, and distance from the urban site. Based on our observations, the propagules infecting the urban plot arrived from at least 560 m if from corn residue, and from at least 1,249 m if from active infections from nearby corn. Although this observation is not replicated, it does indicate that dispersal values from Latin America may not reflect the potential dispersion in Midwest topographies.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-10-20-0082-BR
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2021
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Impacts of Row Spacing and Fungicide Timing on Foliar Disease, Greenstem, and Yield in Double-Cropped Soybeans Grown in the Chesapeake Bay Region of the United States
    Scientific Societies ; 2022
    In:  Plant Health Progress Vol. 23, No. 2 ( 2022-01-01), p. 243-244
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 23, No. 2 ( 2022-01-01), p. 243-244
    Abstract: Double-cropped soybean crops are planted on approximately one-third of crop acres in the Chesapeake Bay region of the United States. Producers have asked whether foliar fungicides are required to optimize yields in this region. We assessed the impacts of foliar fungicide application timing and row spacing on foliar disease, greenstem, and yield from 11 site-years spanning 2017 to 2019. Foliar diseases only developed at rateable levels in one location. Fungicide application, regardless of timing, increased percent greenstem over nontreated controls. Fungicide application did not affect soybean yield. Yield was greater in 38.1-cm rows when compared with 19-cm rows. Our data do not support the use of foliar fungicides in double-cropped soybean production in this region.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-10-21-0130-BR
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2022
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Soybean Yield Loss Estimates Due to Diseases in the United States and Ontario, Canada, from 2015 to 2019
    Scientific Societies ; 2021
    In:  Plant Health Progress Vol. 22, No. 4 ( 2021-01-01), p. 483-495
    Details
    In: Plant Health Progress, Scientific Societies, Vol. 22, No. 4 ( 2021-01-01), p. 483-495
    Abstract: Soybean (Glycine max [L.] Merrill) yield losses as a result of plant diseases were estimated by university and government plant pathologists in 29 soybean producing states in the United States and in Ontario, Canada, from 2015 through 2019. In general, the estimated losses that resulted from each of 28 plant diseases or pathogens varied by state or province as well as year. Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) caused more than twice as much loss as any other disease during the survey period. Seedling diseases (caused by various pathogens), Sclerotinia stem rot (white mold) (caused by Sclerotinia sclerotiorum [Lib.] de Bary), and sudden death syndrome (caused by Fusarium virguliforme O’Donnell & T. Aoki) caused the next greatest yield losses, in descending order. Following SCN, the most damaging diseases in the northern United States and Ontario differed from those in the southern United States. The estimated mean economic loss from all soybean diseases, averaged across the United States and Ontario, Canada was US$45 per acre (US$111 per hectare). The outcome from the current survey will provide pertinent information regarding the important soybean diseases and their overall severity in the soybean crop and help guide future research and Extension efforts on managing soybean diseases.
    Type of Medium: Online Resource
    ISSN: 1535-1025
    URL: Article
    DOI: 10.1094/PHP-01-21-0013-RS
    Language: English
    Publisher: Scientific Societies
    Publication Date: 2021
    detail.hit.zdb_id: 2115009-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...