scholarly journals Molecular Basis for Resistance to Fluazifop-P-Butyl in Itchgrass (Rottboellia cochinchinensis) from Costa Rica

2016 ◽  
Vol 34 (1) ◽  
pp. 143-150 ◽  
Author(s):  
R. CASTILLO-MATAMOROS ◽  
A. BRENES-ANGULO ◽  
F. HERRERA-MURILLO ◽  
L. GÓMEZ ALPÍZAR.
Keyword(s):  
Costa Rica ◽  
Molecular Basis ◽  
Pcr Amplification ◽  
Costa Rican ◽  
Acetyl Coa Carboxylase ◽  
Annual Grass ◽  
San Jose ◽  
Weed Species ◽  
Rottboellia Cochinchinensis ◽  
Grass Weed

Rottboellia cochinchinensis is an annual grass weed species known as itchgrass, or "caminadora" in America´s Spanish speaking countries, and has become a major and troublesome weed in several crops. The application of fluazifop-P-butyl at recommended rates (125 g a.i. ha-1) was observed to be failing to control itchgrass in a field in San José, Upala county, Alajuela province, Costa Rica. Plants from the putative resistant R. cochinchinensis population survived fluazifop-P-butyl when treated with 250 g a.i. ha-1 (2X label rate) at the three- to four-leaf stage under greenhouse conditions. PCR amplification and sequencing of partial carboxyl transferase domain (CT) of the acetyl-CoA carboxylase (ACCase) gene were used to determine the molecular mechanism of resistance. A single non-synonymous point mutation from TGG (susceptible plants) to TGC (putative resistant plants) that leads to a Trp-2027-Cys substitution was found. This Trp-2027-Cys mutation is known to confer resistance to all aryloxyphenoxyproprionate (APP) herbicides to which fluazifop-P-butyl belongs. To the best of our knowledge, this is the first report of fluazifop-P-butyl resistance and a mutation at position 2027 for a Costa Rican R. cochinchinensis population.

Reflecting the Nation: Costa Rican Cinema in the Twenty-First Century

2019 ◽  
pp. 113-180
Author(s):  
Liz Harvey-Kattou
Keyword(s):  
Costa Rica ◽  
Youth Culture ◽  
Costa Rican ◽  
Point Of View ◽  
First Century ◽  
San Jose ◽  
The Uncanny ◽  
Marginalised Groups ◽  
Twenty First Century ◽  
The City

This chapter argues that cinema has been the primary creative vehicle to reflect on national – tico – identity in Costa Rica in the twenty-first century, and it begins with an overview of the industry. Considering the ways in which film is uniquely positioned to challenge social norms through the creation of affective narratives and through the visibility it can offer to otherwise marginalised groups, this chapter analyses four films by key directors. Beginning with an exploration of Esteban Ramírez’s Gestación, it considers youth culture, gender, and class as non-normative spaces in the city of San José. Similarly, Jurgen Ureña’s Abrázame como antes is then discussed from the point of view of its ground-breaking portrayal of trans women in the capital. Two films shot at the geographic margins of the nation are then discussed, with the uncanny coastline the focus of Paz Fábrega’s Agua fría de mar and the marginalized Afro-Costa Rican province of Limón the focus of Patricia Velásquez’s Dos aguas.

scholarly journals Seed shattering phenology at soybean harvest of economically important weeds in multiple regions of the United States. Part 2: grass species

Weed Science ◽  
2020 ◽  
pp. 1-19
Author(s):  
Lauren M. Schwartz-Lazaro ◽  
Lovreet S. Shergill ◽  
Jeffery A. Evans ◽  
Muthukumar V. Bagavathiannan ◽  
Shawn C. Beam ◽  
...  
Keyword(s):  
The United States ◽  
Grass Species ◽  
Annual Grass ◽  
Weed Seed ◽  
Weed Species ◽  
Seed Shattering ◽  
Physiological Maturity ◽  
Rate Of Progression ◽  
Multiple Regions ◽  
Grass Weed

Abstract Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after maturity at multiple sites spread across eleven states in the southern, northern, and mid-Atlantic U.S. From soybean maturity to four weeks after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased as the states moved further north. At soybean maturity, the percent of seed shatter ranged from 1 to 70%. That range had shifted to 5 to 100% (mean: 42%) by 25 days after soybean maturity. There were considerable differences in seed shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output at during certain years.

Evaluation of sequential applications of quizalofop-P-ethyl and florpyrauxifen-benzyl in acetyl CoA carboxylase-resistant rice

2020 ◽  
pp. 1-5
Author(s):  
Tameka L. Sanders ◽  
Jason A. Bond ◽  
Benjamin H. Lawrence ◽  
Bobby R. Golden ◽  
Thomas W. Allen ◽  
...  
Keyword(s):  
Weed Control ◽  
Rice Yield ◽  
Field Studies ◽  
Growth Stages ◽  
Acetyl Coa Carboxylase ◽  
Weed Species ◽  
Rough Rice ◽  
Sequential Treatments ◽  
Acetyl Coenzyme A Carboxylase ◽  
Grass Weed

Abstract Information on performance of sequential treatments of quizalofop-P-ethyl with florpyrauxifen-benzyl on rice is lacking. Field studies were conducted in 2017 and 2018 in Stoneville, MS, to evaluate sequential timings of quizalofop-P-ethyl with florpyrauxifen-benzyl included in preflood treatments of rice. Quizalofop-P-ethyl treatments were no quizalofop-P-ethyl; sequential applications of quizalofop-P-ethyl at 120 g ha−1 followed by (fb) 120 g ai ha−1 applied to rice in the 2- to 3-leaf (EPOST) fb the 4-leaf to 1-tiller (LPOST) growth stages or LPOST fb 10 d after flooding (PTFLD); quizalofop-P-ethyl at 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST or LPOST fb PTFLD; quizalofop-P-ethyl at 139 g ha−1 fb 100 g ha−1 EPOST fb LPOST and LPOST fb PTFLD; and quizalofop-P-ethyl at 85 g ha−1 fb 77 g ha−1 fb 77 g ha−1 EPOST fb LPOST fb PTFLD. Quizalofop-P-ethyl was applied alone and in mixture with florpyrauxifen-benzyl at 29 g ai ha−1 LPOST. Visible rice injury 14 d after PTFLD (DA-PTFLD) was no more than 3%. Visible control of volunteer rice (‘CL151’ and ‘Rex’) 7 DA-PTFLD was similar and at least 95% for each quizalofop-P-ethyl treatment. Barnyardgrass control with quizalofop-P-ethyl at 120 fb 120 g ha−1 LPOST fb PTFLD was greater (88%) in mixture with florpyrauxifen-benzyl. The addition of florpyrauxifen-benzyl to quizalofop-P-ethyl increased rough rice yield when quizalofop-P-ethyl was applied at 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST. Sequential applications of quizalofop-P-ethyl at 120 g ha−1 fb 120 g ha−1 EPOST fb LPOST, 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST, or 139 g ha−1 fb 100 g ha−1 EPOST fb LPOST controlled grass weed species. The addition of florpyrauxifen-benzyl was not beneficial for grass weed control. However, because quizalofop-P-ethyl does not control broadleaf weeds, florpyrauxifen-benzyl could provide broad-spectrum weed control in acetyl coenzyme A carboxylase–resistant rice.

scholarly journals Mathematical Self-Confidence of High School Students: A Study in Costa Rica

2018 ◽  
Vol 23 (1) ◽  
Author(s):  
Luis Gerardo Meza-Cascante ◽  
Evelyn Agüero-Calvo ◽  
Zuleyka Suárez-Valdés-Ayala
Keyword(s):  
High School Students ◽  
Costa Rica ◽  
Educational Level ◽  
Geographical Location ◽  
Costa Rican ◽  
Day Schools ◽  
San Jose ◽  
Education Students ◽  
School Students ◽  
Self Confidence

The “mathematical self-confidence” of the Costa Rican secondary education students is studied using the self-confidence subscale of Fennema and Sherman (1976), and the existence of differences in this variable by sex, educational level and the school geographical location is analyzed as well. The participants in the study were 2984 students (51% female) from the seventh to the eleventh year of official public day schools of the Ministry of Public Education of Costa Rica. The participating schools were selected by simple stratified random sampling and by conglomerates, according to the location area (69.5% urban), and according to the population by province (19.5% Alajuela, 12.5% Cartago, 9.3% Guanacaste, 10.6% Heredia, 10.3% Limon, 9.4% Puntarenas, 28.4% San Jose). The students selected for the study in each school sampled were those belonging to the second group of each educational level (18.9% seventh, 20.5% eighth, 21.4% ninth, 19% tenth, 20.2% eleventh). The results suggest that, jointly, about 78.9% of the students show between high and moderate levels of self confidence. They also indicate the existence of differences in the level of mathematical self confidence according to gender, with lower levels for women, with a medium magnitude of differences. The findings also suggest that there are no differences in the level of mathematical self-confidence among the tenth and eleventh level students, but there are in the ninth level; the latter having the highest index of mathematical self-confidence of the three. The study did not detect differences in the level of mathematical self-confidence among students according to the location of the school. The results suggest, at least, the following lines of research: to delve into the causes of the differences detected in the level of mathematical self-confidence by gender and those that may explain why the level of mathematical self-confidence decreases in the students of Diversified Education.

scholarly journals Variación fonética de /e/ y /r/ en el habla culta de San José

2015 ◽  
Vol 21 (1) ◽  
pp. 115
Author(s):  
Annette Calvo Shadid
Keyword(s):  
Quantitative Analysis ◽  
Costa Rica ◽  
Iberian Peninsula ◽  
Critical Review ◽  
First Generation ◽  
State Of The Art ◽  
Costa Rican ◽  
The State ◽  
San Jose ◽  
Costa Rican Spanish

Este artículo constituye una revisión crítica exhaustiva del estado de la técnica en la realización de los fonemas / r / y / r / en el español de Costa Rica . El artículo también describe la variación de estos fonemas sobre la base del análisis cuantitativo de una muestra, el habla de la primera generación educada de San José. La muestra forma parte de los datos recogidos para el Proyecto Coordinado sobre Variedad de Educación en las ciudades principales de Ibero América y la Península Ibérica.This article constitutes an exhaustive critical review of the state of the art on the realization of the phonemes / r / y / r / in Costa Rican Spanish. The article also describes variation of these phonemes on the basis of the quantitative analysis of a sample of female, first-generation educated speech from San José. The sample is part of the data gathered for the Coordinated Project on Educated Variety in the Main Cities of Ibero America and the Iberian Peninsula.

Clarification of Zamia acuminata and a new Zamia species from Coclé Province, Panama

Phytotaxa ◽  
2013 ◽  
Vol 98 (2) ◽  
pp. 27 ◽  
Author(s):  
ANDERS J. LINDSTRÖM ◽  
MICHAEL CALONJE ◽  
DENNIS STEVENSON ◽  
CHAD HUSBY ◽  
ALBERTO TAYLOR
Keyword(s):  
New Species ◽  
Costa Rica ◽  
Endemic Species ◽  
Type Specimen ◽  
Costa Rican ◽  
Mountain Range ◽  
San Jose ◽  
Leaf Material ◽  
Sterile Leaf ◽  
A New Species

Zamia acuminata has remained an obscure, poorly understood species for over a century due to possibly misinterpreted or erroneous locality data on the unicate sterile type specimen, a very brief protologue description, the misidentification of the plants from El Valle de Antón in Panama as Z. acuminata, and the erroneous determinations of plants of Z. acuminata from Costa Rica as Z. fairchildiana. Recently collected material from San José Province in Costa Rica is here determined to be identical to the single sterile leaf material of the holotype of Zamia acuminata. We consider Z. acuminata to be a Costa Rican endemic species restricted to the western Talamanca mountain range in San José Province, and that the Zamia from El Valle de Antón in Panama, which has previously been referred to as Zamia acuminata, to be a new species, here described as Zamia nana.

The Costa Rican Initiative in Central America

1987 ◽  
Vol 22 (4) ◽  
pp. 457-464 ◽  
Author(s):  
Laurence Whitehead
Keyword(s):  
Costa Rica ◽  
Central America ◽  
Private Property ◽  
Prima Facie ◽  
Costa Rican ◽  
Limited Capacity ◽  
San Jose ◽  
Illegal Activity ◽  
The Will ◽  
The Government

COSTA RICA SHAKES TWO HUNDRED MILES OF underpopulated border with Nicaragua. It has only the most limited capacity to regulate the flow of either weapons into, or refugees out of, the adjacent territory. The absence of a professional army is noteworthy (although it should not be overstated — there are some well armed, but unprofessionally led, defence forces, and the police are quite militarized). What requires emphasis is less the scarcity of soldiers than the abundance of lawyers, and the power of their profession. Last year, for example, tension built up between Managua and San José, because it was revealed that an airstrip in northern Costa Rica had been used to resupply the 'contras' in violation of Costa Rica's proclaimed policy of neutrality. The Sandinistas interpreted this as yet another proof of Costa Rican duplicity and of San José's subordination to the will of the paymasters in Washington. Nicaraguans (of all ideological persuasions) find it almost impossible to accept the Costa Rican version of this episode, which points out that the government has no power to interfere with the use of private property unless a prima facie case exists of illegal activity.

scholarly journals Immersion periods in four neotropical turtles

2011 ◽  
Vol 3 (1) ◽  
pp. 97
Author(s):  
Bernal Morera-Brenes ◽  
Julián Mónge-Nájera
Keyword(s):  
Costa Rica ◽  
Costa Rican ◽  
San Jose ◽  
Significant Parameter ◽  
Adult Females ◽  
Maximum Time ◽  
The Times

NOTA: Semi-aquatic turtles often dive to escape from terrestrial predators, but to our knowledge, the time that Costa Rican species can stay under water is unknown. To obtain preliminary measurements of this ecologically significant parameter, we tested several individuals in an aquarium with water at 25°C in Sabanilla, San José, Costa Rica. We placed the turtles in the water and moved a hand on the surface whenever they attempted to swim upwards, but otherwise allowed them to resurface. They were all adult females except for Kinosternon scorpioides (3 males,1 female).The times they stayed under water were: K. scorpioides 60-3656s (15 repetitions); Kinosternon leucostomum 82-84s (6 repetitions); Rhinoclemmys pulcherrima 413-435s (2 repetitions) and R. funerea 525 seconds (one test).The maximum time was of about one hour, recorded for a female K. scorpioides. Standora et al. (1984) found that in nature, submersion times for the marine Dermochelyx coriacea averaged 480 seconds, similar to the times we recorded for Rhinoclemmys spp.We thank M. Sassa for advice.

scholarly journals Un centro cívico o el réquiem del patrimonio urbano costarricense

REVISTARQUIS ◽  
2017 ◽  
Vol 6 (1) ◽  
Author(s):  
Marcela Muñoz Muñoz
Keyword(s):  
Costa Rica ◽  
Urban Planning ◽  
Costa Rican ◽  
San Jose ◽  
National State ◽  
Urban Heritage ◽  
History Of ◽  
National Model ◽  
Civic Center ◽  
Public Architecture

Resumen Se ofrece una honra póstuma a la arquitectura pública de la capital costarricense, San José, como modelo de ciudad nacional. Por medio del estudio de una discusión legislativa se aborda la conveniencia de dotar al país de un centro cívico nacional, la cual favorece la [in]comprensión de un urbanismo incipiente, anterior a 1970, década en la cual se consolida el derecho urbanístico. Mediante el símil del réquiem, la historia del derecho urbanístico reclama la inutilidad de soluciones jurídicas por salvar valiosas edi caciones que vieran la luz en la conformación del Estado Nacional, durante los siglos XIX y XX. El afán de modernidad de Costa Rica requiere que el derecho urbanístico halle nuevas formas de entender el patrimonio urbano. Abstract This article offers a posthumous honor for public architecture of the Costa Rican capital, San José, as a national model of a city. The study of the discussion contained in certain legislative acts around the convenience to give the country a National Civic Center, [do not] favors the understanding of an emerging Urban Planning before 1970’s, the “legal” decade for the Urban Law. By using the analogy of the requiem, the History of Urban Law demands the futility of legal solutions to save valuable buildings that were born in the formation of the National State, during the 19th and 20th centuries. The Costa Rica ́s quest for modernity claims for new ways where Law can understand Urban Heritage. 

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