Formation of sex organs in the A1 mating type of Phytophthora infestans induced chemically by A2 isolates of other species of Phytophthora

1983 ◽  
Vol 61 (5) ◽  
pp. 1462-1466 ◽  
Author(s):  
Chong-Yao Shen ◽  
Leslie A. Bower ◽  
Donald C. Erwin ◽  
Peter H. Tsao

Oogonia with attached antheridia, many of which contained mature thick-walled oospores, were formed in the A1 mating type of Phytophthora infestans after it had been paired with the A2 mating type of P. parasitica, P. palmivora, P. capsici, or P. infestans, on opposite sides of a polycarbonate membrane. The A2 culture discs, in both top and bottom positions in relation to the polycarbonate membrane, induced sex-organ formation in the A1 isolate of P. infestans. Sex organs were formed in P. infestans at 12, 15, 18, 21, and 24 °C, but they were most abundant at 15 and 18 °C and least at 24 °C. More sex organs in the P. infestans A1 isolate were induced by three A2 isolates of P. parasitica than by an A2 isolate of P. infestans. Evidence was presented that a diffusible oospore-inducing substance was produced by the A2 isolate of P. parasitica in the agar medium even when the A1 isolate of P. infestans was absent on the other side of the membrane. Because both P. infestans and P. parasitica are pathogenic to tomato and potato, such interspecific induction of the formation of selfed oospores in the A1 mating type of P. infestans could play an important role in survival and variation of P. infestans throughout the world.

Plant Disease ◽  
2007 ◽  
Vol 91 (1) ◽  
pp. 109-109 ◽  
Author(s):  
J. M. Segura ◽  
M. de Cara ◽  
M. Santos ◽  
J. Tello

During 2004, an unusual spread of Phytophthora infestans on tomato plants in greenhouses located in Almería and Granada provinces, southern Spain, was observed. Infected plants had water-soaked, brown spots on leaves and stems and necrotic areas with white mold on the surface of fruits. Three isolates were obtained by plating diseased tissue on V8 juice agar medium and maintained on rye agar at 18°C. These isolates were analyzed for the mating type. Crosses were carried out using V8 juice agar and rye agar. The two parental isolates US1 (A1) and US8 (A2) were both provided by W. E. Fry, Cornell University, Ithaca, NY. Two of the Spanish isolates were homothallic and the other isolate belonged to the uncommon mating type A1A2. To confirm the occurrence of the two mating types, 43 single-sporangium progeny were produced and analyzed from the A1A2 mating type. Thirty eight isolates were A1, two were A2, one was A1A2 mating type, and two were sterile. Assessment of five single-sporangium progeny from the homothallic type resulted in two A1, two homothallic, and one sterile isolate. A1A2 isolates produced oospores when crossed with either A1 or A2, but not when self-crossed. Previously, the A1A2 mating type has been found in Israel in the field and was obtained from oospores produced on tomato seeds (2,3). Since 2003, mating types of P. infestans isolates recovered from potato (60) and tomato (8) in southern Spain have been characterized. Seventy-five percent of the isolates recovered from potato were A1 and 25% were A2 mating types. Isolates recovered from tomato were 50% A1 and 50% A2 (1). To our knowledge, this is the first report of the occurrence of the A1A2 mating type and homothallic P. infestans isolates on tomato in Spain. References: (1) E. Andujar et al. Congr. Sociedad Española de Fitopatol. 12:244, 2004. (2) E. Rubin and Y. Cohen. Phytoparasitica 32:237, 2004. (3) E. Rubin and Y. Cohen. Plant Dis. 90:741, 2006.


2013 ◽  
Vol 55 (1) ◽  
pp. 389-400 ◽  
Author(s):  
Hanna Zarzycka ◽  
Sylwester Sobkowiak ◽  
Renata Lebecka ◽  
Beata Tatarowska

The formation of phenotypic structure of <i>P.infestans</i> population in Poland was determined by analyzing 1603 isolates collected from 1987 to 2001. The race complexity, low at the beginning of experiment, has been increasing from year to year and reached in 2001 a high level 7,2 virulence factors per isolate. The single and less composed races dominating firstly in the population were replaced gradually by more composed races. The virulence factors 1, 2, 3, 4, 7 and 11 occurred most frequently, but factors 5 and 8 were noted sporadically. The A2 mating type was detected in 1988 at first and since that time its occurrence has been noted in Polish population each year. The oospores were formed in potato tissues. Race diversity, low at the beginning of the investigation, reached a peak in 1996-2001 . During 1987-1990 weakly and middly aggressive phenotypes dominated in Polish population. In the later period very aggressive isolates were more frequent. Phenotypic race similarity of <i>P.infestans</i> populations in 1987 and 2001 was very low. The race structure of 1987 population was totally different from the race structure of populations of the next years. It was probably due to migration of new pathotypes. On the other hand the variation in complexity, diversity and similarity of races, as well as in aggressiveness observed in later years of investigation can be caused by the presence of both mating types and sexual recombination.


Plant Disease ◽  
1997 ◽  
Vol 81 (9) ◽  
pp. 1094-1094 ◽  
Author(s):  
J. Bakonyi ◽  
T. Érsek

Severe symptoms of potato late blight were observed in July 1996 on potato (Solanum tuberosum L.) cv. Desirée grown on a farm in western Hungary. Isolation was made directly from diseased leaf tissues onto selective pea-agar medium. A recovered isolate, H2a, was identified as Phytophthora infestans (Mont.) de Bary on the basis of Koch's postulates and morphological characteristics of the fungus. Pairing of H2a with isolates of known mating types, A1 and A2 from Germany, revealed that it represents the A2 mating type. After a 2-week incubation on pea-agar medium at 20°C, oospores formed in abundance in the region of contact between the colonies of H2a and the A1 mating type isolate. After extended incubation scattered formation of gametangia was observed when isolate H2a had been paired with itself or with the A2 mating type isolate. The same phenomenon of presumed self fertilization also took place when single, zoospore-derived colonies of H2a were combined with one another or with the known A2 isolate. Of an incomplete set of potato differentials, leaves of potato genotypes r, R2, R3, R4, R1.2.3.4, R7, R8, and R11 were all susceptible to infection with a zoospore suspension of the isolate H2a. The complex virulence phenotype of H2a, its tolerance to metalaxyl in agar cultures and on leaf disks (EC50 >100 mg liter-1), and its A2 mating type behavior collectively suggest that H2a represents a genotype that recently has been introduced into Hungary.


TEKNOSASTIK ◽  
2018 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Dina Amelia

There are two most inevitable issues on national literature, in this case Indonesian literature. First is the translation and the second is the standard of world literature. Can one speak for the other as a representative? Why is this representation matter? Does translation embody the voice of the represented? Without translation Indonesian literature cannot gain its recognition in world literature, yet, translation conveys the voice of other. In the case of production, publication, or distribution of Indonesian Literature to the world, translation works can be very beneficial. The position of Indonesian literature is as a part of world literature. The concept that the Western world should be the one who represent the subaltern can be overcome as long as the subaltern performs as the active speaker. If the subaltern remains silent then it means it allows the “representation” by the Western.


Author(s):  
Iia Fedorova

The main objective of this study is the substantiation of experiment as one of the key features of the world music in Ukraine. Based on the creative works of the brightest world music representatives in Ukraine, «Dakha Brakha» band, the experiment is regarded as a kind of creative setting. Methodology and scientific approaches. The methodology was based on the music practice theory by T. Cherednychenko. The author distinguishes four binary oppositions, which can describe the musical practice. According to one of these oppositions («observance of the canon or violation of the canon»), the musical practices, to which the Ukrainian musicology usually classifies the world music («folk music» and «minstrel music»), are compared with the creative work of «Dakha Brakha» band. Study findings. A lack of the setting to experiment in the musical practices of the «folk music» and «minstrel music» separates the world music musical practice from them. Therefore, the world music is a separate type of musical practice in which the experiment is crucial. The study analyzed several scientific articles of Ukrainian musicologists on the world music; examined the history of the Ukrainian «Dakha Brakha» band; presented a list of the folk songs used in the fifth album «The Road» by «Dakha Brakha» band; and showed the degree of the source transformation by musicians based on the example of the «Monk» song. The study findings can be used to form a comprehensive understanding of the world music musical practice. The further studies may be related to clarification of the other parameters of the world music musical practice, and to determination of the experiment role in creative works of the other world music representatives, both Ukrainian and foreign. The practical study value is the ability to use its key provisions in the course of modern music in higher artistic schools of Ukraine. Originality / value. So far, the Ukrainian musicology did not consider the experiment role as the key one in the world music.


CounterText ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 98-113
Author(s):  
Shaobo Xie

The paper celebrates the publication of Ranjan Ghosh and J. Hillis Miller's Thinking Literature across Continents as a significant event in the age of neoliberalism. It argues that, in spite of the different premises and the resulting interpretative procedures respectively championed by the two co-authors, both of them anchor their readings of literary texts in a concept of literature that is diametrically opposed to neoliberal rationality, and both impassionedly safeguard human values and experiences that resist the technologisation and marketisation of the humanities and aesthetic education. While Ghosh's readings of literature offer lightning flashes of thought from the outside of the Western tradition, signalling a new culture of reading as well as a new manner of appreciation of the other, Miller dedicatedly speaks and thinks against the hegemony of neoliberal reason, opening our eyes to the kind of change our teaching or reading of literature can trigger in the world, and the role aesthetic education should and can play at a time when the humanities are considered ‘a lost cause’.


Author(s):  
Laura Hengehold

Most studies of Simone de Beauvoir situate her with respect to Hegel and the tradition of 20th-century phenomenology begun by Husserl, Heidegger, and Merleau-Ponty. This book analyzes The Second Sex in light of the concepts of becoming, problematization, and the Other found in Gilles Deleuze. Reading Beauvoir through a Deleuzian lens allows more emphasis to be placed on Beauvoir's early interest in Bergson and Leibniz, and on the individuation of consciousness, a puzzle of continuing interest to both phenomenologists and Deleuzians. By engaging with the philosophical issues in her novels and student diaries, this book rethinks Beauvoir’s focus on recognition in The Second Sex in terms of women’s struggle to individuate themselves despite sexist forms of representation. It shows how specific forms of women’s “lived experience” can be understood as the result of habits conforming to and resisting this sexist “sense.” Later feminists put forward important criticisms regarding Beauvoir’s claims not to be a philosopher, as well as the value of sexual difference and the supposedly Eurocentric universalism of her thought. Deleuzians, on the other hand, might well object to her ideas about recognition. This book attempts to address those criticisms, while challenging the historicist assumptions behind many efforts to establish Beauvoir’s significance as a philosopher and feminist thinker. As a result, readers can establish a productive relationship between Beauvoir’s “problems” and those of women around the world who read her work under very different circumstances.


2016 ◽  
Vol 46 (1) ◽  
pp. 38-47
Author(s):  
Geoffrey Squires

Modernism is usually defined historically as the composite movement at the beginning of the twentieth century which led to a radical break with what had gone before in literature and the other arts. Given the problems of the continuing use of the concept to cover subsequent writing, this essay proposes an alternative, philosophical perspective which explores the impact of rationalism (what we bring to the world) on the prevailing empiricism (what we take from the world) of modern poetry, which leads to a concern with consciousness rather than experience. This in turn involves a re-conceptualisation of the lyric or narrative I, of language itself as a phenomenon, and of other poetic themes such as nature, culture, history, and art. Against the background of the dominant empiricism of modern Irish poetry as presented in Crotty's anthology, the essay explores these ideas in terms of a small number of poets who may be considered modernist in various ways. This does not rule out modernist elements in some other poets and the initial distinction between a poetics of experience and one of consciousness is better seen as a multi-dimensional spectrum that requires further, more detailed analysis than is possible here.


2017 ◽  
Vol 39 (2) ◽  
pp. 265-276 ◽  
Author(s):  
Kas Saghafi

In several late texts, Derrida meditated on Paul Celan's poem ‘Grosse, Glühende Wölbung’, in which the departure of the world is announced. Delving into the ‘origin’ and ‘history’ of the ‘conception’ of the world, this paper suggests that, for Derrida, the end of the world is determined by and from death—the death of the other. The death of the other marks, each and every time, the absolute end of the world.


2019 ◽  
Vol 10 (3) ◽  
pp. 244-257
Author(s):  
İclal Kaya Altay ◽  
◽  
Shqiprim Ahmeti ◽  

The Treaty establishing a Constitution for Europe ads territorial cohesion as Union’s third goal, beside economic and social cohesion and lists it as a shared competence. In the other hand, the Lisbon Strategy aims to turn Europe into the most competitive area of sustainable growth in the world and it is considered that the Territorial cohesion policy should contribute to it. This paper is structured by a descriptive language while deduction method is used. It refers to official documents, strategies, agendas and reports, as well as books, articles and assessments related to topic. This paper covers all of two Territorial Agendas as well as the background of territorial cohesion thinking and setting process of territorial cohesion policy.


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