58 research outputs found
Handbook of Florists\u27 Crops Diseases
No full textFebina M. Mathew (with T.J. Gulya, R. Harveson, S. Markell, and C. Block ) is a contributing author, Diseases of the Sunflower.
From the publishers website: Chapters outline up-to-date strategies regarding breeding, chemical and biological control, cultural and environmental manipulation, diagnosis, nutrition, and sanitation and how these approaches directly influence ornamental plant health. This book is a presentation of the latest techniques for disease management by a global team of experts. The book addresses the major diseases of economically important ornamentals with the goal of capturing the latest disease management strategies along with diagnostic photographs. Florists’ crops production has evolved considerably through new technological advances in irrigation, environmental control, along with the appearance of new centers of large scale production of plant material. These changes have necessitated the development of newer and innovative ways of suppressing pathogenic fungi, bacteria, viruses, and nematodes.https://openprairie.sdstate.edu/plant_book/1004/thumbnail.jp
Genome-wide association study identified one major quantitative trait locus associated with resistance to Fusarium proliferatum in soybean (Glycine max)
No full textFusarium root rot is a yield-limiting disease of soybean (Glycine max L.) in the United States and Canada (Ontario). Among the species of Fusarium causing root rot, F. proliferatum is a virulent pathogen. Sources of resistance to F. proliferatum have been identified; however, additional screening of soybean accessions is necessary to identify quantitative trait loci (QTLs) associated with resistance to F. proliferatum. The objective of this study was to evaluate 268 soybean accessions obtained from the USDA Germplasm Collection belonging to maturity groups 000 to IX for resistance to a single isolate of F. proliferatum under greenhouse conditions. Additionally, the study sought to identify QTLs, single-nucleotide polymorphism (SNP) markers, and candidate genes associated with the F. proliferatum resistance through a genome-wide association study (GWAS). The experiment was conducted in a completely randomized design using a layer inoculation method and repeated once. The root rot severity was assessed 21 days postinoculation and expressed as the relative treatment effect (RTE). Fifty-two accessions had a significantly lower RTE compared with the susceptible variety ‘Williams 82’ (ATS = 37.03; df = 7.30; P = 2.47 × 10⁻⁵⁴). GWAS analysis using 36,071 SNP markers identified one major QTL on chromosome 11 that explained 30.95% of the phenotype variance, three strongly associated SNP markers, and three candidate genes that could be involved in resistance to F. proliferatum. This study identified soybean accessions with resistance to F. proliferatum, along with novel SNP markers, which could significantly enhance breeding programs aimed at developing cultivars with resistance to Fusarium root rot.EEA PergaminoFil: Rafi, Nitha. North Dakota State University. Department of Plant Pathology; Estados UnidosFil: Dominguez, Matías. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sector Girasol; ArgentinaFil: Mathew, Febina Merlin. North Dakota State University. Department of Plant Pathology; Estados Unido
Enfermedades del girasol : sclerotinia sclerotiorum (Moho blanco) = Sclerotinia sclerotiorum Diseases of Sunflower (White mold)
No full textLas enfermedades causadas por Sclerotinia sclerotiorum (Lib.) de Bary se encuentran entre las principales adversidades para el cultivo de girasol (Helianthus annuus L.) en el mundo (Harveson et al. 2016; Rashid et al. 2016). El hongo S. sclerotiorum, es también conocido por causar la enfermedad “moho blanco" en numerosos cultivos incluyendo soja (Glycine max L.), colza (Brassica napus L.) y malezas de hoja ancha. La estructura de supervivencia del hongo es el esclerocio, el cual tiene dos mecanismos de germinación, carpogénico y miceliogénico, estos mecanismos permiten al hongo transportarse por vía aérea y también por el suelo. Existen tres diferentes enfermedades causadas por S. sclerotiorum en girasol – (1) Podredumbre de la raíz, podredumbre basal del tallo y marchitez por Sclerotinia; (2) Podredumbre del tallo por Sclerotinia y (3) Podredumbre húmeda del capítulo y podredumbre media del tallo. El desarrollo de estas enfermedades se ve favorecido por temperaturas entre 25 y 30°C, condiciones húmedas prolongadas (como lluvia, niebla, rocío e irrigación) y suelos húmedos. (Markell et al. 2015). El impacto de S. sclerotiorum en el rendimiento de girasol depende del estado fenológico del cultivo al momento de la infección, del manejo agronómico, de las condiciones ambientales prevalentes durante el momento de infección y del tipo de enfermedad que se manifieste (Gulya et al. 2019; Rothmann and McLaren 2018; Harveson et al. 2016; Rashid et al. 2016; Harveson 2011).EEA PergaminoFil: Domínguez, Matías. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sección Girasol; ArgentinaFil: Markell, Samuel. North Dakota State University; Estados UnidosFil: Harveson, Robert. University of Nebraska-Lincoln; Estados UnidosFil: Gulya, Thomas. USDA-ARS Northern Crop Science Laboratory, Sunflower and Plant Biology Research Unit; Estados UnidosFil: Ryley, Malcolm. University of Southern Queensland; AustraliaFil: Thompson, Susan. University of Southern Queensland; AustraliaFil: Block, Charles. Iowa State University; Estados UnidosFil: Mathew, Febina. North Dakota State University; Estados Unido
Development of Glycine max Germplasm Highly Resistant to Sclerotinia sclerotiorum
No full textSclerotinia stem rot (SSR) of soybean caused by Sclerotinia sclerotiorum is a devastating disease of soybean, especially in the Upper Midwest region of the United States. To mitigate yield losses due to this disease, many control methods are available for producers, including cultural control practices, chemical control, and cultivars with quantitative resistance. However, due to there being few commercial cultivars with high levels of resistance, producers are often limited in their seed selection. The aim of this study was to develop novel conventional soybean cultivars with high levels of resistance to SSR, favorable agronomic traits, and resistance to additional economically important diseases. Initial crosses were conducted in 2016 with two different sources of SSR resistance. Across multiple generations of screening for resistance to SSR, three highly resistant soybean lines were identified as the elite lines. These elite lines were demonstrated to be highly resistant across multiple years in both greenhouse and field trials, including high levels of resistance to multiple diverse S. sclerotiorum isolates. The three selected elite lines also resulted in moderately high yields and favorable agronomic traits, such as low lodging and moderate branching, indicating their viability to be released for production. In addition to SSR resistance, these three elite lines demonstrated resistance to other economically important soybean diseases, such as frogeye leaf spot, anthracnose, Cercospora leaf blight, and brown stem rot. Overall, this work has led to three SSR-resistant soybean lines that could be useful for future breeding efforts or commercial soybean production.This article is published as Webster, Richard Wade, Megan McCaghey, Brian Mueller, Carol Groves, Febina Merlin Mathew, Asheesh Singh, Mehdi Kabbage, and Damon L. Smith. "Development of Glycine max Germplasm Highly Resistant to Sclerotinia sclerotiorum." PhytoFrontiers (2023). doi:10.1094/PHYTOFR-01-23-0009-R. Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license
Molecular Characterization and Pathogenicity of Sunflower Stem Pathogens
No full textSunflower (Helianthus annuus L.) production can be limited by several stem diseases.
Among these, Phomopsis stem canker causes frequent yield reductions in Australia, Europe and
North America. In the U.S., while Diaporthe helianthi was assumed to be the sole causal agent,
Diaporthe gulyae was found to cause Phomopsis stem canker in Australia. In order to determine
the causal agent in the U.S., 234 isolates were cultured from 275 infected sunflower stems
collected from the Northern Great Plains. Phylogenetic analyses of the internal transcribed spacer
region, elongation factor subunit 1-?, and actin gene sequences confirmed two species, D.
helianthi and D. gulyae. Four methods were tested to assess the Phomopsis stem canker response
using four D. helianthi isolates on sunflowers. Stem-wound method was adopted for subsequent
experiments based on the recovery of D. helianthi and its correlation with disease severity at 14-
d after inoculation. Aggressiveness of two Diaporthe species was determined in greenhouse and
results suggest they did not vary significantly (p=0.0012) in their aggressiveness, except at 3-d
after inoculation. Among the nine genotypes screened for resistance, USDA ?PI 162784? and ?PI
219649? were less susceptible to the two Diaporthe spp.
Fusarium is commonly regarded a minor pathogen on sunflowers in most production
regions of the world. A total of 110 Fusarium isolates were recovered from 1,637 stalks randomly
sampled for stem diseases in the Northern Great Plains and identified to species level.
Phylogenetic analyses of repetitive-sequence-based polymerase chain reaction fingerprints and
the translation elongation factor 1-alpha gene revealed that Fusarium isolates from sunflowers
represented clades of eight species; namely, F. graminearum, F. proliferatum, F. culmorum, F.
avenaceum, F. oxysporum, F. acuminatum, F. sporotrichioides and F. equiseti. Pathogenicity
studies of eight Fusarium spp. in the greenhouse suggests F. sporotrichioides and F. equiseti were most aggressive. The study comparing the aggressiveness of three Fusarium spp. and V.
dahliae isolates representing six VCGs showed V. dahliae VCG4B and VCG2A were
significantly more aggressive (p ? 0.05) than F. sporotrichioides, F. oxysporum and F. equiseti.
The identification of Diaporthe spp. and Fusarium spp. on sunflowers has implications for
breeding for resistance and disease management.National Sunflower AssociationNorth Dakota State Universit
Six species of Diaporthe associated with Phomopsis stem canker of sunflower in southern Pampean region of Argentina
No full textA survey of 67 commercial fields in 19 locations was conducted in the southern Pampean region of Argentina for Phomopsis stem canker of sunflower (Helianthus annuus L.) between 2014 and 2019. A total of 210 plants having typical symptoms of Phomopsis stem canker were randomly sampled, and fungal isolation was performed. Of the 187 isolates of Diaporthe that were recovered, 94% of the isolates showed morphological characteristics similar to D. helianthi, 3% to D. gulyae, 1% to D. caulivora, 1% to D. sojae, 0.5% to D. kongii, and 0.5% to D. longicolla. Following morphological characterization, the identity of the six morpho-species was confirmed by phylogenetic analyses of b-tubulin, translation elongation factor 1-a, and internal transcribed spacer gene regions. Koch’s postulates were completed for the six fungi by inoculating one susceptible sunflower hybrid with one isolate each of the six species of Diaporthe using the stem-wound inoculation method. Seven days postinoculation, significant differences in disease severity were observed between the six isolates (P < 0.0001), with D. helianthi and D. gulyae isolates causing significantly greater disease severity. To our knowledge, this is the first report of D. kongii, D. longicolla, D. caulivora, and D. sojae associated with Phomopsis stem canker of sunflower in Argentina.Fil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Mancebo, María F.. Advanta Semillas S.A.I.C.; ArgentinaFil: Bazzalo, María E.. Advanta Semillas S.A.I.C.; ArgentinaFil: Reid, Roberto J.. Advanta Semillas S.A.I.C.; ArgentinaFil: Sanchez, María C.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Kontz, Brian J.. South Dakota State University; Estados UnidosFil: Mathew, Febina M.. South Dakota State University; Estados Unido
Insights into the Diaporthe/Phomopsis complex infecting soybeans in the United States
No full textDiaporthe/Phomopsis species are pathogens on a wide range of hosts including soybeans (Glycine max L.), and responsible for several diseases, some of which are of economic importance. Under favorable environmental conditions, these diseases can result in in significant yield losses (Backman et al. 1985). For example, yield losses from Stem canker in the Midwest have ranged from minor to in excess of 50% (Hartman et al. 1999). Four Diaporthe species have been reported pathogenic on soybean – Diaporthe sojae, the causal agent of pod and stem blight; Diaporthe caulivora and Diaporthe aspalathi, causal agents of Northern and Southern stem cankers, respectively; and Diaporthe longicolla, causing seed decay (Hartman et al. 1999).</p
Proses dan Tahapan Recruitment Crew Kapal oleh PT. TJS Marine Indonesia
No full textThis final assignment aims to find out the process and stages of ship crew recruitment by PT. TJS MARINE INDONESIA. The problems that will be discussed in this final assigment focus on the causes of obstacles faced in the implementation of ship crew recruitment mechanisme to facilitate crewing management and what efforts are being made to overcome the obstacles faced. This research was carried out from April to Mei 2024 and the place where this reearch was carriet out was PT. TJS MARINE INDONESIA. This research is descrptive in nature with a qualitative approach. The method used to obtain the required information from related partie is that the author prepares observation, interview and documentation methods to obtain accurate and comprehensive data.Analysis of problems in recruitment and evaluation of the recruitment process implemented by PT. TJS MARINE INDONESIA is used as input.or recommendation for improvements and improvement strategis to increase the efficiency and quality of ship crew recruitment carried out by the compan
Precision Agriculture Basics
No full textSharon A. Clay and F.M. Mathew wit B.M. French are contributing authors, Pest Measurement and Management. Ch.8.
Book description: With the growing popularity and availability of precision equipment, farmers and producers have access to more data than ever before. With proper implementation, precision agriculture management can improve profitability and sustainability of production. Precision Agriculture Basics is geared at students, crop consultants, farmers, extension workers, and practitioners that are interested in practical applications of site-specific agricultural management. Using a multidisciplinary approach, readers are taught to make data-driven on-farm decisions using the most current knowledge and tools in crop science, agricultural engineering, and geostatistics. Precision Agriculture Basics also features a stunning video glossary including interviews with agronomists on the job and in the field
A dagnostic guide of diseases caused by Diaporthe species in soybean
No full textSpecies of Diaporthe cause major diseases in soybean (Glycine max (L.) Merr.), including Diaporthe (Phomopsis) seed decay, pod and stem blight, and stem canker. This diagnostic guide offers an overview of the symptoms caused by Diaporthe species, as well as a summary of methods for culture isolation, identification, long-term storage, and pathogenicity tests
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