scholarly journals Geographical Distribution and Incidence of Orchardgrass Choke, Caused by Epichloë typhina, in Oregon

Plant Disease ◽  
1999 ◽  
Vol 83 (8) ◽  
pp. 754-758 ◽  
Author(s):  
W. F. Pfender ◽  
S. C. Alderman
Keyword(s):  
Disease Incidence ◽  
Dactylis Glomerata ◽  
Willamette Valley ◽  
Cultural Conditions ◽  
The World ◽  
Epichloë Typhina ◽  
Severe Constraint ◽  
Production Area ◽  
One Year ◽  
Choke Disease

A 1998 survey was conducted in the Willamette Valley of Oregon, the major U.S. production area for orchardgrass seed, to determine the extent and severity of choke disease in Dactylis glomerata. This disease is a severe constraint to orchardgrass seed production in other parts of the world, but was unknown in Oregon prior to 1997. Thirty-seven fields, representing 27 cultivars and the geographical extent of production in the Willamette Valley, were selected from a list of fields registered for certification. Choke was found in 26 (70%) of the fields, and disease incidence ranged from <0.05 to 28% tillers affected. Five of the 37 fields had only trace levels of the disease, but four of the fields, representing three counties, had incidences >10%. In a survey of 16 fields located within 3.5 km of the 1997 discovery, choke was found in 14 fields, of which three had incidences >20%. Increase in disease incidence between 1997 and 1998 ranged from 2.1- to 3.3-fold in the three fields where disease increase was measured. One year after its presence was confirmed in Oregon, choke disease of orchardgrass is well-established throughout the orchardgrass seed producing region at damaging levels and is apparently able to increase and spread under the prevailing climatic and cultural conditions.

scholarly journals First Report of Choke Disease Caused by Epichloë typhina on Orchardgrass (Dactylis glomerata) in China

Plant Disease ◽  
2009 ◽  
Vol 93 (6) ◽  
pp. 673-673 ◽  
Author(s):  
C. J. Li ◽  
Z. F. Wang ◽  
N. Chen ◽  
Z. B. Nan
Keyword(s):  
Dactylis Glomerata ◽  
The United States ◽  
Leaf Sheath ◽  
Climatic Conditions ◽  
Disease Spread ◽  
Willamette Valley ◽  
First Report ◽  
Epichloë Typhina ◽  
Pure Cultures ◽  
Choke Disease

Orchardgrass or cocksfoot (Dactylis glomerata L.) has been widely cultivated as a forage crop in many provinces of China (1). It is also a native perennial forage grass, which grows at the edge of forests, shrubs, and mountainous grasslands in Xinjiang and Sichuan (2). In September of 2007, signs of choke disease on orchardgrass were observed in a native grassland under birch woodland near Altai City, Xinjiang, China. Stromata, which formed on culms of diseased grass, enclosing the inflorescence and leaf sheath, were 4.5 to 5.5 mm long, smooth or wrinkled, white and later becoming yellowish or yellow, tuberculate, dry, and covered with perithecia. Inflorescences surrounded by fungal stromata were choked and failed to mature, thus restricting seed production. Pure cultures were obtained by directly scraping stromata from the surface and incubating it on antibiotic potato dextrose agar (PDA). The colonies were cottony, white on the upper surface, and white to yellow on the reverse. The growth rate was 13 to 21 mm per week at 25°C on PDA. Conidia were hyaline, lunate to reniform, and measured 4.1 ± 0.5 × 2.2 ± 0.5 μm. They accumulated in small globose heads at the tips of conidiogenous cells and were produced singly on conidiophores of 13 to 33 μm long and 2.7 to 4.1 μm wide at the base. Internal transcribed spacer (ITS) sequence by BLAST search had 99% similarity with an Epichloë typhina isolate of orchardgrass in Spain (GenBank Accession No. AM262420.1). Cultural characteristics, microscopic examination, and phylogenetic analysis showed that this choke disease on D. glomerata was caused by the fungus E. typhina (Pers.) Tul. & C. Tul. as described by White (4). To our knowledge, this is the first report of E. typhina causing choke disease on orchardgrass in China. The pathogen has been identified in France, England, Germany, Sweden, Switzerland, and the United States (3,4) with the same symptoms as those reported here. In 1997, choke disease was found in 70% of the fields in the Willamette Valley of Oregon, with disease incidences ranging from 0.05 to 28%. It was predicted to increase and spread under the prevailing climatic conditions (3). This new disease report is to provide observational and diagnostic information to help with recognition and prevention of disease spread in orchardgrass cultivation regions of China. References: (1) X. R. Chao et al. Shandong Agric. Sci. 1:7, 2005. (2) S. X. Jia, ed. China Forage Plant Flora. China Agriculture Press, Beijing, 1987. (3) W. F. Pfender and S. C. Alderman. Plant Dis. 83:754, 1999. (4) J. W. White. Mycologia 85:444, 1993.

scholarly journals Effect of some factors on the incidence of choke (Epichloë typhina) in grass seed stands in the Czech Republic

2012 ◽  
Vol 48 (No. 1) ◽  
pp. 10-16 ◽  
Author(s):  
B. Cagaš ◽  
R. Macháč
Keyword(s):  
Disease Incidence ◽  
Dactylis Glomerata ◽  
Phleum Pratense ◽  
The Other ◽  
Stand Age ◽  
The Czech Republic ◽  
Grass Seed ◽  
Orchard Grass ◽  
Choke Disease ◽  
Very High

Choke of grasses caused by Epichlo&euml; typhina occurred in 2008 and 2009 in more than 25% of grass seed stands of timothy (Phleum pratense and P. nodosum); a lower incidence was reported in orchard grass (Dactylis glomerata). A decline in disease incidence in 2010 was caused partly by a reduction in the total area of grasses grown for seed production and partly by a decrease of older grass seed stands. The incidence of choke in timothy varieties Odenw&auml;lder and Pampas was very high; they differed statistically from the other 24 grown cultivars. No difference was found among 21 varieties of orchard grass. The highest incidence of choke was observed in varieties Comer and Dolina (timothy) and Amera (orchard grass). The incidence of choke in cultivated varieties of Phleum spp. and D. glomerata was affected by stand age (the incidence of the disease in timothy was recorded in 13% of stands in the first cropping year and in 50% of stands in the fifth cropping year). Choke disease occurred in all regions where the species were grown for seed. &nbsp;

scholarly journals Pression d’inoculum de la maladie des raies noires (MRN) causée par Mycosphaerella fijiensis Morelet, dans les plantations industrielles de bananiers, en Côte d’ivoire

2016 ◽  
Vol 12 (3) ◽  
pp. 37
Author(s):  
B. Essis ◽  
K. Kobenan ◽  
S. Traoré ◽  
J. Yatty ◽  
D. Koné ◽  
...  
Keyword(s):  
Acceptable Level ◽  
Effective Management ◽  
Mycosphaerella Fijiensis ◽  
The World ◽  
Industrial Plantation ◽  
Black Leaf Streak ◽  
Production Area ◽  
Black Leaf Streak Disease ◽  
One Year ◽  
Inoculum Pressure

The Black Leaf Streak Disease (BLSD) is one of main parasitic constraints of the agro-industrial plantations of banana in the world. Caused by a fungus ascomycete (Mycosphaerella fijiensis Morelet), the losses of yield are up to 50 %, without of resistant cultivars and effective management. This study relative to the level of the disease has been conducted in 12 industrial plantation in 6 production area: Aboisso, Grand- Bassam, Dabou, Agboville, Azaguié and Tiassalé; for a total surface of 2576 ha. The observations concerned the ranks of Youngest Leaf Spotted (YLS), of the Youngest Leaf Necrosed (YLN), the Number of Standing Leaves (NSL) and the gap between the Youngest Leaf Spotted and the Number of Standing Leaves. The results showed that chronic re-infestation of industrial plantation during the last five years, except CDBCI Tiassalé-Songon in 2011 and 2012. An acceptable level of re-infestation was observed in 2012 on other plantations, with the rank of YLS greater than or equal to 3, except BATIA Tiassalé and CDBCI Azaguié. The internal inoculum pressure (YLS) varied a lot from one plantation to another and from one year to another. Except plantation SBMK Aboisso and BATIA Tiassalé, other plantations had at least one value of the rank of the top YLS or equal to 8, during the study indicating a relatively low severity of the BLSD. From 2009 to 2012, all plantations have shown over 8 standing leaves, the minimum required for proper filling of the bunch of banana regime at the time of flowering.

First Report of Dicyma pulvinata on Epichloë typhina and Its Potential for Control of E. typhina

2010 ◽  
Vol 11 (1) ◽  
pp. 25 ◽  
Author(s):  
Stephen C. Alderman ◽  
Sujaya Rao ◽  
Ruth Martin
Keyword(s):  
Seed Production ◽  
Biocontrol Agent ◽  
Field Conditions ◽  
High Humidity ◽  
Willamette Valley ◽  
First Report ◽  
Epichloë Typhina ◽  
Low Humidity ◽  
First Time ◽  
Choke Disease

The hyperparasite Dicyma pulvinata is reported for the first time on Epichloë typhina, which causes choke disease in orchardgrass seed production fields in the Willamette Valley, OR. In an orchardgrass field near Corvallis, OR, D. pulvinata was found on 7% of E. typhina stromata. Infected stromata had fewer perithecia and appeared shrunken, desiccated, and pale gray to grayish-white, in contrast to the orange colored noninfected stromata with mature perithecia. In greenhouse inoculations, D. pulvinata significantly (P < 0.05) reduced perithecial formation on E. typhina. However, under field conditions, a significant (P < 0.05) reduction in perithecial development occurred in one trial initiated in mid-May, but not in a second trial initiated in early June, although D. pulvinata sporulated on 92% of the inoculated stromata from each trial within 72 h after their incubation in moist chambers. Under field conditions, D. pulvinata may have potential as a biocontrol agent of E. typhina if applied when stromata start to emerge during mid late April to early May when rain and high humidity conditions are typical. However, development of D. pulvinata would likely be limited by low humidity conditions that often occur during mid- to late June in the Willamette Valley. There are currently no effective chemical or cultural controls for choke in orchardgrass. Accepted for publication 3 November 2009. Published 16 February 2010.

History Turmoil And Politico-Cultural Conditions of the Sub-Continental Men In Salman Rushdie’s Midnight’s Children

2015 ◽  
Vol 2 (2) ◽  
pp. 26-28
Author(s):  
Gunasekaran N ◽  
Bhuvaneshwari S
Keyword(s):  
Middle Class ◽  
Salman Rushdie ◽  
Fiction Writing ◽  
Pluralistic Society ◽  
Post Colonial ◽  
Cultural Conditions ◽  
The World ◽  
Midnight's Children ◽  
First Time

Salman Rushdie remains a major Indian writer in English. His birth coincides with the birth of a new modern nation on August 15, 1947. He has been justly labelled by the critics as a post-colonial writer who knows his trade well. His second novel Midnight’s Children was published in 1981 and it raised a storm in the hitherto middle class world of fiction writing both in English and in vernaculars. Rushdie for the first time burst into the world of fiction with subversive themes like impurity, illegitimacy, plurality and hybridity. He understands that a civilization called India may be profitably understood as a dream, a collage of many colours, a blending of cultures and nationalities, a pluralistic society and in no way unitary.

Clinton Commits U.S. Troops To Follow-On Force In Bosnia: Peace Implementation Council Meets in London

1997 ◽  
Vol 8 (1) ◽  
pp. 79-86
Keyword(s):  
World War Ii ◽  
World War ◽  
The World ◽  
One Year

One year ago in Dayton, the leaders of Bosnia, Croatia and Serbia turned from the horror of war to the promise of peace. Their historic decision came after nearly four years of horrible bloodshed, the bloodiest conflict Europe has seen since World War II; after a quarter million deaths, after 2 million people were made refugees, after countless atrocities that shocked the conscience of the world.

Histopathological spectrum of oral cavity lesions – A tertiary care experience

2021 ◽  
Vol 8 (3) ◽  
pp. 364-368
Author(s):  
Ishani Gupta ◽  
Rekha Rani ◽  
Jyotsna Suri
Keyword(s):  
Squamous Cell Carcinoma ◽  
Retrospective Study ◽  
Oral Cancer ◽  
Oral Cavity ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Tertiary Care ◽  
Proper Management ◽  
The World ◽  
One Year

Oral cancer is one of a major health problem in some parts of the world especially in the developing countries. Oral cancer is the sixth most common cancer in the world whereas in India it is one of the most prevalent cancer. Oral cavity lesions are usually asymptomatic. Accurate diagnosis of the lesion is the first step for the proper management of patients and histopathology is considered as the gold standard. The objective is to study the different patterns of oral cavity lesions seen in a tertiary care hospital of Jammu: One year retrospective study. Post graduate department of pathology.: It was a retrospective study carried out in a tertiary care centre for a period of one year from March 2020 to Feb 2021. 148 cases of oral cavity lesions were included in this study. The parameters that were included in the study were sociodemographic data, site of the lesion, clinical features and histological diagnosis. Data collected was analysed.148 cases of oral lesions were identified during the period of study. The age of patients varied from 5 to 78years and Male to Female ratio was 2.2:1. Buccal mucosa (30%) was the most common site involved which was followed by tonsil (19%). Out of 148 cases 70 cases were malignant, 10 cases pre malignant and 21 cases were benign. Squamous cell carcinoma (33.7%) was the most common lesion present in our study. Oral cavity lesions have a vast spectrum of diseases which range from tumour like lesions to benign and malignant tumours. Our study concluded that squamous cell carcinoma was the most common malignant lesion of oral cavity. Histological typing of the lesion is important for confirmation of malignancy and it is essential for the proper management of the patient.

scholarly journals POWER-KNOWLEDGE RELATIONS IN THE FIELD OF POLITICAL ECOLOGY

2017 ◽  
Vol 20 (3) ◽  
pp. 225-256 ◽  
Author(s):  
ENRIQUE LEFF
Keyword(s):  
Latin America ◽  
Critical Thinking ◽  
Political Ecology ◽  
Human Life ◽  
The State ◽  
Environmental Crisis ◽  
Cultural Conditions ◽  
The World ◽  
English Speaking ◽  
Open Dialogue

Abstract The current environmental crisis calls for thinking about the state of the world: the thermodynamic-ecological and symbolic-cultural conditions of organic and human life on the planet. In this regard, it stresses the need to realize the unawareness and life’s unsustainability that humanity has created. In this text I discuss and take a stand about some of the concepts and founding and constitutive research lines of political ecology. In this way I pretend to open dialogue by placing in context some of the principles, ideas, and founding viewpoints of political ecology in Latin America and contrasting them with those from the English-speaking school of thought. I intend not only to establish a political socio-geography, but to question the epistemic core of political ecology, and to stimulate a more cosmopolitan critical thinking in order to be able to face the hegemonic powers that lead the world into social and environmental decay

International Sugar Council

1951 ◽  
Vol 5 (2) ◽  
pp. 416-416
Keyword(s):  
United States ◽  
South Africa ◽  
The United States ◽  
World Market ◽  
Sugar Production ◽  
Special Committee ◽  
The United Kingdom ◽  
The World ◽  
One Year ◽  
Preliminary Draft

A meeting of the International Sugar Council was held in London, June 26 to July 20, 1950. The meeting was attended by delegates of Australia, Belgium, Brazil, Cuba, Czechoslovakia, Dominican Republic, France, Haiti, Indonesia, the Netherlands, Peru, Philippine Republic, Poland, Portugal, South Africa, the United Kingdom, Yugoslavia, and the United States. The purpose of the meeting was to discuss the world situation in sugar and the proposal for a new international sugar agreement. The council adopted a protocol which extended the international sugar agreement of 1937 one year from August 31, 1950. During 1950, the council created a special committee to 1) study the changing sugar situation as it related to the need or desirability for negotiating a new agreement, and 2) report to the council, as occasion might arise, on its findings and recommendations as to the possible basis of a new agreement. The special committee prepared a document which set forth certain proposals in the form of a preliminary draft agreement. The draft agreement included six fundamental bases: 1) the regulation of exports, 2) the stabilization of sugar prices on the world market, 3) a solution to the currency problem, 4) the limitation of sugar production by importing countries, 5) measures to increase consumption of sugar and 6) the treatment of non-signatory countries. The draft was then considered by the council at its meeting on July 20 at which time the council decided to submit it to member and observer governments for comments and to transmit such comments for consideration at a meeting of the special committee.

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