Biotechnological approaches for improved disease resistance in soybean and wheat

Doctor of PhilosophyDepartment of Plant PathologyHarold N. TrickIncreasing food production is required for the ever-increasing population. Reducing crop losses due to plant pathogens is a viable method of increasing this production. An estimated 12.5% of crop productivity is lost each year to plant pathogens. Here we explore two methods that utilize biotechnology for increasing resistance of common bread wheat (Triticum aestivum L.) to fungal pathogens, and soybean (Glycine max (L.) Merr.) to soybean cyst nematode (SCN; Heterodera glycines Ichinohe). Fungi are responsible for the largest amount of yield loss among plant pathogens. We have introduced six antifungal peptides (zeamatin, drosomycin, juruin, ARACIN, Ace-AMP1, and a wasabi gamma-thionin) into wheat via particle bombardment as single transgene lines along with a glufosinate resistance marker (BAR). Coding sequences (CDSs) were constitutively expressed via the pAHC17 plasmid. Lines expressing these genes were challenged with the ascomycete fungal pathogens Pyrenophora tritici-repentis, and Fusarium graminearum; as well as the basidiomycete fungal pathogen Tilletia laevis. Despite high levels of expression compared to housekeeping genes, these transgenes did not show enhanced resistance to these fungal pathogens. Zeamatin, drosomycin, and juruin CDSs were also subcloned into the soybean-optimized constitutive expression vector pGmubi. The other focus of this work looks at reducing reproductive success of SCN in the SCN/soybean pathosystem by exploiting SCN sex pheromones. SCN males have been shown to be attracted to females by several organic compounds, namely vanillic acid (VA). Here we engineer a pathway to produce VA in soybean in an attempt to mask females from males, thus lowering their reproductive success. Because of the long regeneration time required to recover transgenic soybean from particle bombardment of calli, preliminary work was conducted to show proof-of-concept. To check for inhibition of VA on soybean at SCN working concentrations, pouch bioassays were performed on 13-day old soybean seedlings. Root length of these seedlings was not inhibited by VA. Greenhouse experiments were conducted where susceptible soybean were challenged with SCN in the presence of different concentrations of exogenously applied VA. These assays did not show a reduction in cyst or egg numbers on soybean roots. A 3 dehydroshikimate dehydratase (3DSD) from Podospora anserina and a catechol o-methyltransferase (COMT) from Nicotiana tubacum were chosen for converting the shikimate pathway compound 3-dehydroshikimic acid into VA in planta. A Petunia x hybrida chloroplast targeting sequence fusion of these CDSs were subcloned into the pGmubi vector. These plasmids were introduced into soybean via particle bombardment either co-bombarded with the hygromycin resistance conferring plasmid pHyg, or tri-bombarded. Two greenhouse experiments were performed where T₁ soybean expressing 3DSD, COMT, and 3DSD+COMT were challenged with SCN. These plants did not show a reduction in numbers of cysts harvested from roots. More work needs to be done to dismiss this concept by doing larger greenhouse experiments with T₂ seed and plants expressing transgenes need to be characterized for production of VA. These observations indicate that VA may not act as a sex pheromone for SCN and needs to be investigated further

Morphological variation and genetic diversity of Triops cancriformis (Crustacea: Notostraca) and their potential for understanding the influence of postglacial distribution and habitat fragmentation

Triops cancriformis (Crustacea: Notostraca) occurs in ephemeral habitats like rain pools or floodplain pools distributed over a large geographical range. The named habitats are disturbed by human impacts and, consequently, T. cancriformis is endangered throughout its distribution range. In the present thesis the populated habitats and threats are characterised and further morphological and genetic variations detected among and within European populations are reported. On the basis of recent investigations it is shown that T. cancriformis subspecies separation is hampered by an individual variability which points to the necessity of species revision. The analysis of mitochondrial gene sequence data suggests that the species has colonised most of Europe very recently. The advantage of a complex reproductive strategy in T. cancriformis in this process is discussed. The population structure resolved with nuclear DNA markers highlights that there is low allelic diversity among and within populations compared to other Branchiopoda (Daphnia). By means of the present study it can be shown that habitat conservation is most important to protect T. cancriformis

Soil Protists Diversity, Distribution and Ecological Functioning

Soil protists occupy key nodes in soil food webs due to their high abundance, fast turnover and functional importance as bacterial grazers. However, methodological drawbacks obscure the knowledge of soil protists, so that many taxa remain unknown. The structure of natural protist communities and taxa-specific ecological functions are also largely unknown. This thesis aims to increase the knowledge on soil protists using a variety of approaches. In the first part, naked amoebae being presumably the most neglected protist morphogroup were cultivated from several distinct geographical locations across Europe and from high altitude sites in Tibet. During the course of this study, 16 new species and seven new genera were discovered, representing two eukaryotic supergroups (Amoebozoa and Excavata), three classes (Discosea, Variosea and Heterolobosea), and 12 genera (Cochliopodium, Stenamoeba, Acanthamoeba, Ischnamoeba n.g., Darbyshirella n.g., Heliamoeba n.g., Arboramoeba n.g., Angulamoeba n.g., Telaepolella, Schizoplasmodiopsis, Allovahlkampfia and Pagea n.g.). This vast number of taxonomic descriptions unveils the tremendous lack of knowledge especially on soil naked amoebae. The second part aims at deciphering the diversity and community structure of soil protists using four different techniques. First, a modified cultivation technique enabled the quantification of individual morphogroups, allowing determination often up to genus level. It was shown that soil moisture not only impacts the total abundance, but also affects the community composition of soil protists. Second, established cultures of morphologically indistinguishable Acanthamoeba spp. were sequenced, enabling differentiation to strain level. Highly diverse Acanthamoeba communities were detected that differed between geographically remote soils. Third, a high-throughput amplicon sequencing approach targeting the protist phylum Cercozoa illustrated that cercozoan communities strongly differed between geographically distant soils and that community composition depended on the type of land management. Finally, a metatranscriptomic approach unveiled the entire active protist community in different soil and litter samples, uncovering a previously unknown diversity. Each of these methods confirmed that soils harbour an enormous diversity of protists and all methods detected differences in soil protist communities depending on geographic origin or treatment. Therefore it is important to understand the respective advantages and disadvantages associated with each of those methods. Further, available skills, equipment and financial resources need to be considered before applying a method to study soil protists. The third part of this thesis aims to elucidate rarely considered ecological functions performed by soil protists. Generally, soil protists are considered as bacterivores, but diverse protists facultatively consumed fungi. The small amoeba Cryptodifflugia operculata revealed another feeding mode – trapping and consuming nematodes. Metatranscriptomic data revealed high relative abundances of both functional groups in all terrestrial soil samples indicating wider ecological functions carried out by soil protists as has been suggested before

Bryophyte Ecology

Bryophyte Ecology is an ebook comprised of 5 volumes written by Janice Glime, Professor Emerita of Biological Sciences at Michigan Technological University. Chapter coauthors include Irene Bisang, S. Robbert Gradstein, J. Lissner, W. J. Boelema, and D. H. Wagner. To download smaller sections of Bryophyte Ecology, visit: https://digitalcommons.mtu.edu/bryophyte-ecology/https://digitalcommons.mtu.edu/oabooks/1003/thumbnail.jp

UNDERSTANDING INFORMATION USE IN ONLINE CONSUMER-HEALTH SUPPORT GROUPS: A LOOK INTO INTERACTIVE HEALTH COMMUNICATIONS

UNDERSTANDING INFORMATION USE IN ONLINE CONSUMER HEALTH SUPPORT GROUPS: A LOOK INTO INTERACTIVE HEALTH COMMUNICATIONS The exponential growth of the Internet in the past two decades has been accompanied by an increased interest by Internet users in communicating among each other electronically about all sorts of topics, including health-related issues. This increased interest in peer-to-peer communication for health topics raised lots of questions about the potential harmful effects of these communications on those participants who might take some health-related action without consulting with a doctor first. This potential problem has motivated the researcher to investigate how people with certain health conditions use health information that they obtain from online support groups. Even though the understanding of how information is sought, retrieved, and ultimately used is a very important topic within information behavior research, information use is an area that has seen less study. For this reason, the researcher decided to investigate information use within online consumer health support groups using a content analytical approach. The study had two specific objectives: (a) to describe what some of the cognitive, affective, and behavioral actions that consumers indicate they had taken based on information shared within some of the online support groups to which they belong; and (b) to determine if the uses given to information follow any pattern among different chronic conditions being studied with relation to the type of questions asked, the type of reply messages, and the health-related content of the messages. Methodologically, the study used computer-mediated discourse analysis to guide collection of trace data that came from archives of selected online discussion boards related to the three chronic conditions chosen for the study. For data to be part of the study, the presence of interactions with indications of usefulness was necessary. Then, through content analysis, the data was coded using several classification schemas found in the literature, some of them in their original form, others adapted to fit this research purpose. These schemas looked into the types of questions asked, the functions of the reply messages, the type of medical content of the posted messages, and the type of use given to the information. Once all the data was processed, the researcher looked for patterns among the different variables and across the different gender-based chronic conditions. Results of the analysis show that the message characteristics of content type, function of reply messages, and question types, have a significant relationship with the types of conditions. Message characteristics also show a significant relationship with the cognitive, affective, and behavioral information uses. Discussions of the results as well as some alternatives for future research are presented. Enter Abstract here late

The geology of New Hampshire : a report comprising the results of explorations ordered by the legislature, Part. I physical geography

https://scholars.unh.edu/geology_books/1002/thumbnail.jp

Validité et fidélité de la combinaison de l’anamnèse et de l’examen physique pour le diagnostic des pathologies communes au genou

Résumé Les douleurs au genou font partie des motifs de consultation les plus fréquents auprès d’un médecin ou d’un professionnel de la santé. Les pathologies communes au genou incluent celles d’origine traumatique telles les déchirures du ligament croisé antérieur ou les déchirures méniscales et celles d’apparition progressive telles les déchirures méniscales dégénératives, l’ostéoarthose du genou ou le syndrome fémoro-patellaire. Les données probantes démontrent qu’un diagnostic initial valide, basé sur une évaluation musculosquelettique bien accomplie par un intervenant ayant une formation adéquate, permet l’initiation rapide d’un traitement ciblé. Cependant, le manque de connaissances dans l’évaluation musculosquelettique et les erreurs diagnostiques fréquentes dans notre système de santé favorisent l’utilisation inappropriée des tests d’imagerie médicale et augmentent les références non pertinentes en chirurgie orthopédique. Les données probantes sont actuellement limitées et incomplètes concernant la validité et la fidélité de l’évaluation musculosquelettique combinant l’anamnèse et l’examen physique pour orienter le diagnostic différentiel des pathologies au genou. L’amélioration des connaissances en lien avec l’évaluation musculosquelettique des adultes souffrant de douleurs au genou est donc nécessaire afin d’améliorer l’efficience de nos soins de santé. Cette thèse propose deux objectifs: 1- évaluer l’accord diagnostique entre un physiothérapeute utilisant une évaluation musculosquelettique standardisée sans imagerie et des médecins experts pour les différentes pathologies communes au genou; 2- évaluer la validité de la combinaison de l’anamnèse et de l’examen physique afin de développer une série d’outils valides permettant d’orienter le diagnostic différentiel de quatre pathologies communes au genou. Nous avons évalué deux cent soixante-dix-neuf participants, présentant 359 diagnostics primaires et secondaires incluant : 43 participants ayant une déchirure du ligament croisé antérieur, 80 participants présentant une déchirure méniscale, 129 participants atteints d’ostéoarthrose du genou, 75 atteints d’un syndrome fémoro-patellaire et 32 participants présentant une autre pathologie au genou. Le physiothérapeute qui exécutait une évaluation musculosquelettique standardisée a démontré un excellent accord diagnostique avec des médecins experts dont le diagnostic était basé sur une évaluation musculosquelettique combinée aux résultats des tests d’imagerie (k=0,89; IC95%: 0,83-0,94). Sur la base de l’évaluation musculosquelettique réalisée indépendamment par le physiothérapeute, nous avons pu développer une série de combinaisons d’éléments de l’anamnèse et de tests de l’examen physique pour orienter le diagnostic différentiel des pathologies au genou. Nous avons démontré qu’un individu qui consultait pour une douleur au genou dont l’origine est un traumatisme du genou en pivot, ayant ressenti un « pop » au moment du traumatisme et chez qui les tests de Lachman ou du pivot shift sont positifs, a une probabilité élevée de souffrir d’une déchirure du ligament croisé antérieur avec un rapport de vraisemblance positif de 38,4 (IC95%: 16,0-92,5). Si un individu décrit un traumatisme au genou avec pivot accompagné d’une douleur localisée au côté médial du genou et qu’il démontre une douleur à la palpation de l’interligne articulaire interne, celui-ci a une probabilité élevée de souffrir d’une déchirure méniscale avec un rapport de vraisemblance positif de 8,9 (IC95%: 6,1-13,1). Un individu présentant une douleur d’apparition progressive au côté médial du genou présente dans les activités qui nécessitent des pivots et qui démontre à l’examen physique un alignement neutre du membre inférieur ou une flexion passive complète du genou, celui-ci a une probabilité modérée d’être atteint d’une déchirure méniscale dégénérative avec un rapport de vraisemblance positif de 6,4 (IC95%: 4,0-10,4). Si toutefois un individu consultant pour une douleur d’apparition progressive est âgé de plus de 50 ans, qu’il a un indice de masse corporel supérieur à 30 et qu’il démontre à l’examen physique la présence d’un alignement au genou en varus ou en valgus, des crépitements à la palpation du genou ou une limitation de l’amplitude articulaire passive en extension, il a une probabilité élevée d’être atteint d’ostéoarthrose du genou avec un rapport de vraisemblance positif de 13,6 (IC95%: 6,5-28,4). Finalement, un individu qui présente une douleur isolée en antérieur du genou accompagnée de difficultés dans les escaliers, d’une douleur à la palpation des facettes rotuliennes et d’une extension passive complète du genou, celui-ci a une probabilité élevée de souffrir d’un syndrome fémoro-patellaire avec un rapport de vraisemblance positif de 8,7 (IC95%: 5,2-14,6). En résumé, les résultats de cette thèse démontrent qu’il existe un accord diagnostique élevé entre un physiothérapeute qui procède à une évaluation musculosquelettique sans recours à des tests d’imagerie et des médecins experts qui basent leur diagnostic sur l’examen physique et les résultats des tests d’imagerie chez des adultes souffrant de douleurs au genou. Les combinaisons des éléments de l’anamnèse et de l’examen physique développées dans cette thèse permettent d’orienter le diagnostic différentiel de différentes pathologies communes au genou avec une validité considérée modérée à élevée. Ces combinaisons devront être validées dans d’autres contextes cliniques, notamment en première ligne, avant une utilisation clinique répandue.Knee complaints are among the most common reasons for consulting a healthcare practitioner. Common knee disorders include those of traumatic onset such as anterior cruciate ligament or meniscal tears, or those of progressive onset such as degenerative meniscal tears, knee osteoarthritis or patellofemoral pain syndrome. An early diagnosis to guide toward an efficient management is advocated to prevent persistence of pain, functional limitations and loss of quality of life in affected individuals. However, evidence currently shows an overreliance on medical imaging tests and inappropriate orthopaedic surgery referrals, thus delaying initiation of treatment. Evidence is currently limited concerning the validity and reliability of combining history elements and physical examination tests to support the differential diagnosis of common knee disorders. To answer this evidence gap, this thesis had two objectives: 1- to assess inter-rater diagnostic agreement between a physiotherapist using only a standardized musculoskeletal examination and expert physicians using a musculoskeletal examination in combination with imaging tests for the diagnosis of common knee disorders; 2- to assess the diagnostic validity of clusters combining history elements and physical examination tests and produce a series of tools to support the differential diagnosis of four common knee disorders. We prospectively recruited two hundred and seventy-nine participants presenting 359 primary and secondary diagnoses including: 43 participants with an anterior cruciate ligament tear, 80 subjects had a meniscal tear, 129 suffered from knee osteoarthritis, 75 were diagnosed with patellofemoral pain syndrome and 32 presented other knee diagnoses. The physiotherapist achieved high inter-rater agreement with the expert physicians for the diagnosis of common knee disorders (k= 0.89; 95%CI:0.83-0.94). Multiple clusters combining history elements and physical examination tests were developed to support the differential diagnosis of knee disorders. Our results show that an individual consulting for a knee complaint following trauma during a pivot and describing a “popping sensation” during the trauma as well as showing a positive Lachman or pivot shift tests has a high probability of having an anterior cruciate ligament tear with a positive likelihood ratio of 38.4 (95%CI: 16.0-92.5). If this individual consulting for a knee complaint following trauma during a pivot experience medially located knee pain, confirmed with medial joint line tenderness at palpation, the subject has a high probability of having a meniscal tear of traumatic origin with a positive likelihood ratio of 8.9 (95%CI: 6.1-13.1). An individual consulting for a complaint of progressive onset with isolated medially located pain during activities requiring a pivot, who also presents a normal knee alignment or full passive knee flexion, has a moderate probability of having a degenerative meniscal tear with a positive likelihood ratio of 6.4 (95%CI: 4.0-10.4). If this individual complaining of knee pain of progressive onset is older than 50 years old, has a body mass index higher than 30 and at physical examination presents knee crepitus at palpation, a valgus or varus knee misalignment or a restricted passive knee extension, he has a high probability of having symptomatic knee osteoarthritis with a positive likelihood ratio of 13.6 (95%CI: 6.5-28.4). Lastly, an individual consulting for isolated anterior knee pain with difficulty descending stairs, palpable patellar facets tenderness and full passive knee extension has a high probability of having a patellofemoral pain syndrome with a positive likelihood ratio of 8.7 (95%CI: 5.2- 14.6). Overall, the results demonstrated high inter-rater diagnostic concordance between providers and that combining selected history elements and physical examination tests was moderately to highly valid to support the differential diagnosis of common knee disorders. The proposed diagnostic clusters will require external validation in various clinical contexts, including primary care, before widespread implementation in clinical practice

Twentieth Fungal Genetics Conference Scientific Program

Abstracts are published as an electronic supplement to Fungal Genetics Newsletter # 46 and should be cited as follows: Fungal Genet. Newsl. 46S: Abstract Numbe