Common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass [C. dactylon (L.) Pers. X C. transvaalensis Burtt-Davy] are some of the most common turfgrasses used on athletic fields. Subsequently, the traffic tolerance of commercially available cultivars and the effects of trinexapac-ethyl (TE) on bermudagrass athletic fields with or without perennial ryegrass are often limited. A two year study at the University of Tennessee was conducted under simulated athletic field traffic to evaluate the performance of bermudagrass cultivars as affected by TE and overseeding. Bermudagrass cultivars evaluated were Tifway, Riviera, Patriot, and Celebration. TE treatments consisted of an untreated control, TE at 76.3 g a.i. ha-1 every 14 days until 14 days prior to trafficking (TE A), and TE at 76.3 g a.i. ha-1 every 14 days until 14 days after trafficking (TE B). Overseeding treatments consisted of no overseeding and overseeding at 670 kg ha-1 of perennial ryegrass (Lolium perenne L.). Plots were rated for percent green cover using digital image analysis after every 5 traffic events. Soil physical characteristic measurements were performed after every traffic season. Morphological data was determined by measuring number of leaves, internode lengths, leaf angle, and leaf width of the bermudagrass. Cultivar was significant for percent green cover for both years of this study with Tifway and Celebration having the highest ratings and Patriot having the lowest rating. TE was also significant for percent green cover for the first 10 traffic events with TE treatment B having lower percent cover values. Morphological characteristic was significant for leaf angle for both years of the study. A more vertical leaf angle to the shoot occurred in the more traffic resistant cultivars Tifway and Celebration. Finally, both TE treatments yielded higher percent green cover values in 2008 when morphological characteristic data was collected and a more vertical leaf angle to the shoot occurred compared to the untreated control. Tifway, Celebration, and Riviera when applied with trinexapac-ethyl before the traffic season and overseeded with perennial ryegrass would be beneficial for athletic field managers.

Conservation tillage programs have been successfully implemented for many agronomic cropping systems, but adoption of reduced tillage for vegetable crops has been slow. As many conventionally managed conservation tillage programs rely on synthetic herbicides for clean cultivation, alternative methods must be devised to suppress weed pressure and reduce reliance on mechanical cultivation to aid in the development of reduced tillage programs for organic cropping system. Strip tillage is a reduced tillage method that is well suited to vegetable crop production, and the utilization of cover crops and living mulches between rows provides a viable weed management option for organic systems. The adoption of reduced tillage and the inclusion of cover crops and living mulches have the potential to alter the agroecosystem in ways that impact plant development and crop yield, and augment weed, insect and disease pressure. The current study focuses on the use of strip tillage and the interplanting of spring-seeded living mulches and overwintered cover crops for early-season organic broccoli production. Data were collected on ground cover provided by cover crops and living mulches, crop physiological status (petiole sap nitrate, photosynthetic rate, plant growth and crop biomass) and pest pressure (weed relative abundance, insect density and disease incidence and severity). Living mulches provided the greatest ground coverage when cover crop establishment was poor; however, when cover crops produced a large amount of biomass, living mulch establishment was suppressed. Decreases in herbivorous pests and suppression of grassy and cool-season weed species were also observed, indicating that strip tillage and the use of spring-seeded living mulches and overwintered cover crops may provide beneficial pest management strategies. Decreases in crop growth and biomass, and decreases in petiole sap nitrate were observed, however, indicating reductions in crop vigor and yield may be expected with the implementation of strip tillage and living mulch crops. It is suggested that the utilization of strip tillage and living mulch crops may provide benefits to pest management which may outweigh declines in yield.

The purpose of this thesis is to describe and analyse the reception and development of the orangery in the county of Uppland, Sweden, during the 18th century. A main obstacle for the gardeners and their governors must have been the local climate in Uppland, a county at the south border of Norrland, the very north part of Sweden. The local climate during the 18th century in Uppland was rather cold with yearly temperature averages well under the “normal” during Baroque and Renaissance time. Two questions are discussed in the thesis. First question is: could the orangery buildings serve the purpose to protect fruit-trees from the harsh climate in Uppland i.e. had the orangeries built during the 18th century in Uppland at Walloon furnaces the expected capability to allow Asian fruit-trees like Citrus to pass the winter? The second question is: were the gardeners capable to force citrus blossoms to fruit? The study is based on sources of different kinds, such as gardening accounts from Walloon furnaces, contracts of service, inventories, wage bills, estate inventories, gardening manuals, horticultural handbooks and travelogues. To be able to go more closely into the matter I have done simulations of some orangery buildings thermal behaviour by using a building performance simulation software called IDA. The answer to the first question is that the orangeries served their purpose, at all events during normal winters. But during extreme winters the citrus trees must have been damaged. And the problems with importing rare Asian fruit-trees via the Netherlands, Portugal and Italy were overwhelming. The ambitions to acclimatize the trees to the harsh climate north of Stockholm, at the borderline to the north part of Sweden, were admirable. The whole idea of creating gardens of central European style and to build and maintain orangeries at high costs in the severe climate of county Uppland must have been a central European idea of lifestyle, or more likely the pleasure of the governers own satisfaction. The answer to the second question in the thesis is that I have not found any proof for production, even in a very small scale, of any citrus fruits in orangeries at Walloon furnaces in Uppland during the 18th century. / QC 20100714

In the fall of 2011, a study was initiated at the Western Kentucky University Farm in Bowling Green, Kentucky on a Crider silt loam (Typic Paleudalf). The objective of this study was to determine cultivar, mowing height, and herbicide effects on bermudagrass, Cynodon dactylon [L.] Pers., suppression in tall fescue, Schedonorus arundinaceus [Schreb.] Dumort., nom. cons. The experimental design was a split plot design with whole plots consisting of varying mowing heights and split plots consisting of different herbicide treatments with three replications. Two separate experiments were conducted. The tall fescue variety ‘KY 31’ was utilized for one study and the turf type cultivar ‘Bullseye’ was utilized in the other. In the fall of 2011, glyphosate (Roundup Pro) was applied to selected plots at the rate of 0.36 kg ae/ha. ‘KY 31’ and ‘Bullseye’ tall fescues were sown into an existing mixed stand of common and hybrid bermudagrass at 342 kg pls/ha. Mowing heights were maintained at 7.62 cm, 10.16 cm, and 12.70 cm. In the spring of 2012, treatments containing fenoxaprop (Acclaim Extra), mesotrione (Tenacity), and fluazifop (Fusilade II) were applied to selected plots at the rates of 0.07 kg ai/ha, 0.48 kg ai/ha, and 0.24 kg ai/ha respectively. A non-ionic surfactant at 0.25% (v/v) was utilized in treatments containing mesotrione and fluazifop. Three weeks later these treatments were applied a second time. Data were collected visually on turf quality, tall fescue cover, broadleaf weed cover, and bermudagrass cover. The study was repeated in 2012 – 2013. Fluazifop and glyphosate + fluazifop resulted in significantly lower turf quality than all other treatments up until ten weeks after initial treatment. Treatments containing fluazifop significantly reduced tall fescue cover but also significantly suppressed bermudagrass cover the greatest. However, these treatments also resulted in the greatest amount of broadleaf weed cover. High mowing heights may play a role in achieving high turf quality ratings and better broadleaf weed and bermudagrass suppression in forage type tall fescue than in turf type tall fescue.

Im Zeitraum von 2008 bis 2011 wurden jährlich über 140 Stauden sowie weitere 120 Staudenarten aus Zwiebeln und Knollen als Schnittblume aus dem Freiland getestet. Ergebnis ist ein 77 Arten umfassendes Sortiment von Stauden mit guten Anbaueigenschaften und Stielqualitäten, die für den zeitigen Absatz bis Ende Juni empfohlen werden. Das Empfehlungssortiment an Schnittstauden aus Zwiebeln und Knollen umfasst 73 Kulturen. Die vorgestellten »Pillnitzer Wochensträuße« verdeutlichen die vielfältigen Möglichkeiten, ab Mitte April ohne Verfrühungsmaßnahmen Schnittblumen von Stauden im Freiland zu erzeugen. Beispielrechnungen zeigen, dass sich mit Schnittstauden im Freilandanbau gute Erlöse erzielen lassen. Investitionen und Energiekosten fallen nicht an bzw. sind gering.

Untersucht wurde die Verbreitung der meldepflichtigen Krankheiten Apfeltriebsucht und Birnenverfall in Anlagen mit integrierter und ökologischer Produktion. Anhand der Krankheitssymptome wurde der Einfluss auf Ertrag und Fruchtqualität erfasst, die Populationsentwicklung der Phytoplasma übertragenden Blattsauger und die Wirkung von Insektiziden beurteilt. In älteren Apfel- und Birnenanlagen waren bis zu 20% der Bäume erkrankt. Die Äpfel der erkrankten Bäume der Sorte Jonagored hatten ein deutlich geringeres Einzelfruchtgewicht und schlechter ausgefärbte Früchte. Die Übertragung der Apfeltriebsucht durch den Vektor Cacopsylla picta fand von Ende Mai bis Anfang Juli statt. Spritzungen im April mit den Insektiziden Calypso und Spruzit reduzierten deutlich die Population der Blattsauger.

<p>The truffle genus Tuber (Ascomycota, Pezizales, Tuberaceae) produces underground mushrooms widely sought as edible fungi. Tuber species are distributed throughout Northern hemisphere forests and form obligate ectomycorrhizal symbiosis with trees within the Pinaceae, Fagaceae, Betulaceae, and Juglandaceae. </p><p>The transition to a truffle form (from an epigeous form) has occurred independently, multiple times in both the Ascomycetes and Basidiomycetes. One instance has given rise to the Tuberaceae, which is composed entirely of obligate ectomycorrhizal species. Attempts to cultivate European truffle species T. melanosporum, T. aestivum, and T. borchii are underway in North America and other parts of the world and have been met with mixed success.</p><p>The overarching goal of my dissertation is to address the systematics, ecology, and biogeography of Tuber within a phylogenetic framework. Multiple loci were sequenced from Tuber ascoma collected worldwide including ectomycorrhizae, though an emphasis was placed on sampling taxon within North American. Maximum likelihood, maximum parsimony, and Bayesian inference were used for phylogenetic reconstructions. </p><p>A taxonomic and phylogenetic overview of the family Tuberaceae is presented in Chapter 1. Tuber is resolved as monophyletic. In Chapter 2, through greater taxon sampling including epigeous and hypogeous Helvellaceae outgroups and related South American taxa, a resolved multi-gene phylogeny of the Tuberaceae and putative epigeous ancestor of Tuber is presented. A previously unknown South American lineage that contains both epigeous and hypogeous taxa is resolved as sister to the Tuberaceae. Chapter 3 is focused on issues of cryptic speciation and taxonomy within the Tuber gibbosum clade. The four species resolved in the Gibbosum clade appear to be endemic to the Pacific Northwest and associated primarily with Gymnosperms. Chapter 4 is a meta-analysis of all known Tuber ITS rDNA sequences (e.g. from Genbank and generated from herbarium collections) available at the time. These were placed within the Tuber phylogeny to assess species diversity, long-distance dispersal, and host associations. In total, 120 phylotypes were detected (based on a 96% similarity criterion). Tuber shows high levels of continental endemism. I hypothesize that species shared between continents and having low ITS variability (<1%) are the result of recent human-mediated introduction events. Chapters 5 and 6 are focused on the ectomycorrhizal ecology of the economic truffle T. lyonii, which is native to Eastern and Southern North America. There is a phenomenon of Tuber lyonii fruiting in pecan orchards. Pecans (Carya illinoinensis) are in the Juglandaceae, an understudied ectomycorrhizal plant family. I sampled the ectomycorrhizal communities of pecan orchards (associated with the production of the North American truffle species Tuber lyonii). In Chapter 5 I discuss four Tuber taxa discovered in these pecan orchards, their abundance and haplotype diversity. Chapter 6 examines the ectomycorrhizal communities across the five pecan orchards sampled. I show that multiple Tuber species, including Tuber lyonii, are dominant in the ectomycorrhizal community. Chapters 7 and 8 focus on black truffles in the Melanosporum clade. In Chapter 7 I document that Tuber indicum has been introduced into North America multiple times, and through ectomycorrhizal synthesis I demonstrate that this Asian species can associate readily with angiosperm and gymnosperm hosts endemic to North American. In Chapter 8 I describe a quick and reliable method for the determination of Tuber melanosporum. The method is based on direct PCR and species-specific primers and is very useful for rapid diagnostics. I have adapted this approach for other truffle and mushroom species. </p><p>Three major findings emerge from my dissertation research: 1) Tuber is more diverse than previously realized; 2) Tuber exhibits high levels of regional and continental endemism; 3) Taxonomic issues remain in many species complexes worldwide (including the Tuber candidum complex in North America, the Tuber excavatum complex in Europe, the Tuber indicum complex in Asia). Taxonomic challenges also remain regarding species known only from ectomycorrhizal or anamorphic states. The discovery of additional Tuber species is expected as the truffle flora of undersampled regions become better studied and incorporated into the Tuberaceae phylogeny.</p> / Dissertation

Common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass [C. dactylon (L.) Pers. X C. transvaalensis Burtt-Davy] are some of the most common turfgrasses used on athletic fields. Subsequently, the traffic tolerance of commercially available cultivars and the effects of trinexapac-ethyl (TE) on bermudagrass athletic fields with or without perennial ryegrass are often limited. A two year study at the University of Tennessee was conducted under simulated athletic field traffic to evaluate the performance of bermudagrass cultivars as affected by TE and overseeding. Bermudagrass cultivars evaluated were Tifway, Riviera, Patriot, and Celebration. TE treatments consisted of an untreated control, TE at 76.3 g a.i. ha-1 every 14 days until 14 days prior to trafficking (TE A), and TE at 76.3 g a.i. ha-1 every 14 days until 14 days after trafficking (TE B). Overseeding treatments consisted of no overseeding and overseeding at 670 kg ha-1 of perennial ryegrass (Lolium perenne L.). Plots were rated for percent green cover using digital image analysis after every 5 traffic events. Soil physical characteristic measurements were performed after every traffic season. Morphological data was determined by measuring number of leaves, internode lengths, leaf angle, and leaf width of the bermudagrass. Cultivar was significant for percent green cover for both years of this study with Tifway and Celebration having the highest ratings and Patriot having the lowest rating. TE was also significant for percent green cover for the first 10 traffic events with TE treatment B having lower percent cover values. Morphological characteristic was significant for leaf angle for both years of the study. A more vertical leaf angle to the shoot occurred in the more traffic resistant cultivars Tifway and Celebration. Finally, both TE treatments yielded higher percent green cover values in 2008 when morphological characteristic data was collected and a more vertical leaf angle to the shoot occurred compared to the untreated control. Tifway, Celebration, and Riviera when applied with trinexapac-ethyl before the traffic season and overseeded with perennial ryegrass would be beneficial for athletic field managers.

Thesis (Ph.D.)--Murdoch University, 2008. / Thesis submitted to the Faculty of Sustainability, Environmental and Life Sciences. Includes bibliographical references (leaves 118-134)

Thèse 3e cycle : Économie rurale : Montpellier I : 1980. / Bibliogr. p. I-IV.