scholarly journals Use of Several Natural Products from Selected Nicotiana Species to Prevent Black Shank Disease in Tobacco

2016 ◽  
Vol 27 (3) ◽  
pp. 113-125 ◽  
Author(s):  
Antoaneta B. Kroumova ◽  
Ivan Artiouchine ◽  
George J. Wagner
Keyword(s):  
North Carolina ◽  
Natural Products ◽  
Antifungal Activity ◽  
Large Scale ◽  
Leaf Surface ◽  
Negative Effects ◽  
Black Shank ◽  
Plant Infection ◽  
Resistant Varieties ◽  
Race 1

SUMMARY Black shank is a major annual disease threat to all types of tobacco worldwide. It is caused by the fungus Phytophthora parasitica var. nicotianae (PPN). The major tobacco growing areas in US - Kentucky, Tennessee and North Carolina can experience devastating losses, reaching in some fields up to 100%. Thus far, the main approaches to control this disease have been creation of resistant varieties, fungicide treatments, and crop rotation. Some fungicides are reported to have negative effects on the environment. The goal of this work was to test the antifungal activity of several natural products that are synthesized by certain Nicotiana species, and secreted to the leaf surface. We hypothesized that phylloplanin, cis-abienol, labdenediol and sclareol can suppress PPN-race 0- and PPN-race 1-caused disease in Burley tobaccos KY 14 and MS KY 14 × L8LC in the greenhouse. We developed methods for leaf surface extraction, spore preparation and soil drench application of the natural compounds tested. Experiments were performed on 5–8 week-old greenhouse grown seedlings. cis-Abienol showed high inhibitory properties toward the disease. Race 0 infection was completely subdued in KY 14 while race 1 infection was reduced by 70–80%, and delayed by 6–10 days in KY 14 and MS KY14 × L8LC. Sclareol was very effective in inhibiting race 0-caused disease in both tobacco cultivars. In MS KY 14 × L8LC race 1 infection was inhibited while in KY 14 it was reduced by 85% and delayed by 6 days. Labdenediol reduced the disease by half in eight week-old KY 14 plants. Tobacco phylloplanin reduced plant infection by both races by 50–60% and delayed the disease by 6–10 days. Phylloplanin was least suppressive in both tobacco cultivars. We consider sclareol to be the best candidate for future studies due to its antifungal properties and availability. cis-Abienol, despite its good antifungal activity, is not feasible for large-scale use due to the production and stability limitations.

scholarly journals Occurrence of Race 3 of Phytophthora nicotianae in North Carolina, the Causal Agent of Black Shank of Tobacco

Plant Disease ◽  
2010 ◽  
Vol 94 (5) ◽  
pp. 557-562 ◽  
Author(s):  
C. A. Gallup ◽  
H. D. Shew
Keyword(s):  
North Carolina ◽  
Phytophthora Nicotianae ◽  
Infested Soil ◽  
Yield Losses ◽  
Black Shank ◽  
First Report ◽  
History Of ◽  
Race 1 ◽  
Nicotiana Longiflora ◽  
First Time

Black shank, caused by the oomycete Phytophthora nicotianae, causes significant annual yield losses in tobacco. Race 3 of P. nicotianae is reported here for the first time from North Carolina. It was identified from a North Carolina tobacco field with a history of tobacco varieties with Phl gene resistance and numerous field sites with no known deployment of varieties with the Phl gene. Race 3 was originally described from cigar-wrapper tobacco in Connecticut in the 1970s, but has not been reported in any other location since. Race 3 was defined as overcoming the Phl gene from Nicotiana longiflora but not the Php gene from N. plumbaginifolia. Stem and root inoculations were conducted on a set of host differentials to determine the virulence of North Carolina isolates. Stem inoculation was unable to distinguish between races 0 and 3 of P. nicotianae and is not a reliable method of identifying these virulence types. Race 1 gave a unique phenotype using stem inoculation. Root inoculation was the only reliable means of distinguishing between races 0 and 3. This is the first report of race 3 in North Carolina and the first report of damage to seedlings from root inoculations and to plants containing the Phl gene in naturally infested soil.

СОЦИАЛЬНО-ЭКОНОМИЧЕСКИЕ КОНФЛИКТЫ В РАМКАХ «КАПИТАЛИЗМА ПЛАТФОРМ»

2019 ◽  
Vol 14 (3) ◽  
pp. 33
Author(s):  
L. V. Tomin
Keyword(s):  
Large Scale ◽  
Network Effects ◽  
Corporate Control ◽  
Balance Of Power ◽  
Negative Effects ◽  
Potential Threat ◽  
Communication Infrastructure ◽  
Political Effects ◽  
Information And Communication ◽  
Integrated Information

The article is devoted to the analysis of the structure, the peculiarities of functioning and the socio-economic and political effects of the «platform capitalism». The basis of this model is the network effects produced by the integrated information and communication infrastructure, which contribute to the monopolization and the constant expansion of platform companies into new areas. The principle of functioning of this infrastructure is the continuous collection and further monetization of data extracted from the interactions of individuals among themselves or with one of the elements of a digitalized economy or government structures. Such an infrastructure — forms a potential threat of strengthening state and corporate control over citizens. In addition, the activities of platform companies produce negative effects on the labor market, reinforcing the process of precarization of employment. The integrated information and communication infrastructure of platform companies form a system of a kind of «digital Taylorism», which deprives the employee of autonomy and privacy in the workplace. The influence of digitalization, subjected to the technocratic logic of the neoliberal model of governance in democratic countries, strengthens the de-politicization of relations between the citizen and the state and further changes the balance of power between labor and capital in favor of the latter. Large-scale protests of the last years against the companies of “capitalism of platforms” demonstrated the structural contradictions of this model and formed new forms of organization and actions of grassroots workers of the “digital economy”.

Towards Control of an Estuary

1987 ◽  
Vol 19 (9) ◽  
pp. 155-174
Author(s):  
Henk L. F. Saeijs
Keyword(s):  
Shallow Water ◽  
Storm Surge ◽  
Salt Marshes ◽  
Large Scale ◽  
Western Europe ◽  
Oxygen Depletion ◽  
Negative Effects ◽  
Intertidal Flats ◽  
Environmental Consequences ◽  
Short Time

The Delta Project is in its final stage. In 1974 it was subjected to political reconsideration, but it is scheduled now for completion in 1987. The final touches are being put to the storm-surge barrier and two compartment dams that divide the Oosterschelde into three areas: one tidal, one with reduced tide, and one a freshwater lake. Compartmentalization will result in 13% of channels, 45% of intertidal flats and 59% of salt marshes being lost. There is a net gain of 7% of shallow-water areas. Human interventions with large scale impacts are not new in the Oosterschelde but the large scale and short time in which these interventions are taking place are, as is the creation of a controlled tidal system. This article focusses on the area with reduced tide and compares resent day and expected characteristics. In this reduced tidal part salt marshes will extend by 30–70%; intertidal flats will erode to a lower level and at their edges, and the area of shallow water will increase by 47%. Biomass production on the intertidal flats will decrease, with consequences for crustaceans, fishes and birds. The maximum number of waders counted on one day and the number of ‘bird-days' will decrease drastically, with negative effects for the wader populations of western Europe. The net area with a hard substratum in the reduced tidal part has more than doubled. Channels will become shallower. Detritus import will not change significantly. Stratification and oxygen depletion will be rare and local. The operation of the storm-surge barrier and the closure strategy chosen are very important for the ecosystem. Two optional closure strategies can be followed without any additional environmental consequences. It was essential to determine a clearly defined plan of action for the whole area, and to make land-use choices from the outset. How this was done is briefly described.

scholarly journals Strategic deployment of riparian buffers and windbreaks in Europe can co-deliver biomass and environmental benefits

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Oskar Englund ◽  
Pål Börjesson ◽  
Blas Mola-Yudego ◽  
Göran Berndes ◽  
Ioannis Dimitriou ◽  
...  
Keyword(s):  
Agricultural Production ◽  
Large Scale ◽  
Production Systems ◽  
Riparian Buffers ◽  
Environmental Benefits ◽  
The European Union ◽  
Negative Effects ◽  
Nitrogen Emissions ◽  
Environmental Objectives ◽  
Eu Policies

AbstractWithin the scope of the new Common Agricultural Policy of the European Union, in coherence with other EU policies, new incentives are developed for farmers to deploy practices that are beneficial for climate, water, soil, air, and biodiversity. Such practices include establishment of multifunctional biomass production systems, designed to reduce environmental impacts while providing biomass for food, feed, bioenergy, and other biobased products. Here, we model three scenarios of large-scale deployment for two such systems, riparian buffers and windbreaks, across over 81,000 landscapes in Europe, and quantify the corresponding areas, biomass output, and environmental benefits. The results show that these systems can effectively reduce nitrogen emissions to water and soil loss by wind erosion, while simultaneously providing substantial environmental co-benefits, having limited negative effects on current agricultural production. This kind of beneficial land-use change using strategic perennialization is important for meeting environmental objectives while advancing towards a sustainable bioeconomy.

scholarly journals Large-scale transcriptomics to dissect 2 years of the life of a fungal phytopathogen interacting with its host plant

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Elise J. Gay ◽  
Jessica L. Soyer ◽  
Nicolas Lapalu ◽  
Juliette Linglin ◽  
Isabelle Fudal ◽  
...  
Keyword(s):  
Host Plant ◽  
Large Scale ◽  
Field Experiments ◽  
Plant Residues ◽  
Plant Infection ◽  
Effector Genes ◽  
Controlled Conditions ◽  
Niche Adaptation ◽  
Depth Analysis ◽  
Fungal Genes

Abstract Background The fungus Leptosphaeria maculans has an exceptionally long and complex relationship with its host plant, Brassica napus, during which it switches between different lifestyles, including asymptomatic, biotrophic, necrotrophic, and saprotrophic stages. The fungus is also exemplary of “two-speed” genome organisms in the genome of which gene-rich and repeat-rich regions alternate. Except for a few stages of plant infection under controlled conditions, nothing is known about the genes mobilized by the fungus throughout its life cycle, which may last several years in the field. Results We performed RNA-seq on samples corresponding to all stages of the interaction of L. maculans with its host plant, either alive or dead (stem residues after harvest) in controlled conditions or in field experiments under natural inoculum pressure, over periods of time ranging from a few days to months or years. A total of 102 biological samples corresponding to 37 sets of conditions were analyzed. We show here that about 9% of the genes of this fungus are highly expressed during its interactions with its host plant. These genes are distributed into eight well-defined expression clusters, corresponding to specific infection lifestyles or to tissue-specific genes. All expression clusters are enriched in effector genes, and one cluster is specific to the saprophytic lifestyle on plant residues. One cluster, including genes known to be involved in the first phase of asymptomatic fungal growth in leaves, is re-used at each asymptomatic growth stage, regardless of the type of organ infected. The expression of the genes of this cluster is repeatedly turned on and off during infection. Whatever their expression profile, the genes of these clusters are enriched in heterochromatin regions associated with H3K9me3 or H3K27me3 repressive marks. These findings provide support for the hypothesis that part of the fungal genes involved in niche adaptation is located in heterochromatic regions of the genome, conferring an extreme plasticity of expression. Conclusion This work opens up new avenues for plant disease control, by identifying stage-specific effectors that could be used as targets for the identification of novel durable disease resistance genes, or for the in-depth analysis of chromatin remodeling during plant infection, which could be manipulated to interfere with the global expression of effector genes at crucial stages of plant infection.

Risk Factors for a Positive Hepatitis C Status in Fishermen in Kuantan Malaysia

2019 ◽  
Vol 31 (3) ◽  
pp. 227-237
Author(s):  
Priya Lall ◽  
Rumana Saifi ◽  
Diva Baggio ◽  
Samantha Fitzsimmons Schoenberger ◽  
Martin Choo ◽  
...  
Keyword(s):  
Hepatitis C ◽  
Confidence Interval ◽  
Risk Taking ◽  
Odds Ratio ◽  
Large Scale ◽  
Adjusted Odds Ratio ◽  
Environmental Drivers ◽  
Negative Effects ◽  
Risk Taking Behaviors ◽  
Risk Communities

Malaysia currently has an estimated hepatitis C virus (HCV) prevalence of 1.3% with an infected population of 384,000. Fishermen in Malaysia are at risk of HCV infection due to injection drug use and disproportionately high rates of incarceration. This study used quantitative data from Project WAVES, a large-scale mixed methods project charting environmental drivers of risk-taking behaviors among a respondent-driven sample of 406 fishermen in Malaysia. Over a quarter of participants (27.9%) reported injecting drugs in the past month; 49.8% of the sample tested positive for HCV. Respondents who had previously been arrested displayed increased odds of being HCV-positive (adjusted odds ratio = 4.79, confidence Interval = 2.46-9.35). Participants who reported being in lock-up displayed close to 6-fold odds of being HCV-infected (adjusted odds ratio = 5.49, confidence interval = 2.77-10.90, P < .001). These findings underscore the need for policies and structural interventions targeting the negative effects of aggressive incarceration contributing to the burden of HCV among high-risk communities.

Total synthesis of the potent antifungal agents bengazole C and E

2009 ◽  
Vol 74 (6) ◽  
pp. 887-900 ◽  
Author(s):  
Álvaro Enríquez-García ◽  
Steven V. Ley
Keyword(s):  
Natural Products ◽  
Antifungal Activity ◽  
Total Synthesis ◽  
Marine Natural Products ◽  
Antifungal Agents ◽  
Nitrile Oxide ◽  
Total Syntheses ◽  
Unique Structure

The bengazoles are marine natural products with unique structure, containing two oxazole rings flanking a single carbon. They show very potent antifungal activity. The total syntheses of bengazole C and E are described following a convergent route which involves diastereoselective cycloaddition of an appropriately substituted nitrile oxide with a butane-1,2-diacetal-protected alkenediol as the key step.

scholarly journals Investigation of Atmospheric Rivers Impacting the Pigeon River Basin of the Southern Appalachian Mountains

2018 ◽  
Vol 33 (1) ◽  
pp. 283-299 ◽  
Author(s):  
Douglas K. Miller ◽  
David Hotz ◽  
Jessica Winton ◽  
Lukas Stewart
Keyword(s):  
North Carolina ◽  
River Basin ◽  
Large Scale ◽  
Large Fraction ◽  
Appalachian Mountains ◽  
Warm Season ◽  
Atmospheric Rivers ◽  
Southern Appalachian Mountains ◽  
Low Level ◽  
Southern Appalachian

Abstract Rainfall observations in the Pigeon River basin of the southern Appalachian Mountains over a 5-yr period (2009–14) are examined to investigate the synoptic patterns responsible for downstream flooding events as observed near Knoxville, Tennessee, and Asheville, North Carolina. The study is designed to address the hypothesis that atmospheric rivers (ARs) are primarily responsible for the highest accumulation periods observed by the gauge network and that these periods correspond to events having a societal hazard (flooding). The upper 2.5% (extreme) and middle 33% (normal) rainfall events flagged using the gauge network observations showed that half of the heaviest rainfall cases were associated with an AR. Of those extreme events having an AR influence, over 73% had a societal hazard defined as minor-to-major flooding at the USGS river gauge located in Newport, Tennessee, or flooding observations for locations near the Tennessee and North Carolina border reported in the Storm Data publication. Composites of extreme AR-influenced events revealed a synoptic pattern consisting of a highly amplified slow-moving positively tilted trough, suggestive of the anticyclonic Rossby wave breaking scenario that sometimes precedes hydrological events of high impact. Composites of extreme non-AR events indicated a large-scale weather pattern typical of a warm season scenario in which an anomalous low-level cyclone, cut off far from the primary upper-tropospheric jet, was located in the southeastern United States. AR events without a societal hazard represented a large fraction (75%–88%) of all ARs detected during the study period. Synoptic-scale weather patterns of these events were fast moving and had weak low-level atmospheric dynamics.

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