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Intera??es alelop?ticas de culturas de inverno sobre soja
No full textIn the southern region of Brazil, wheat (Triticuma estivum), black oats (Avena
strigosa) and canola (Brassica napus) are croped in winter period aiming soil cover
and grain production. However, there is no information about possible allelopathic
interactions of these crops over soybeans in the Miss?es region, Rio Grande do Sul
state, Brazil. So, the objective of this work was to evaluate the allelopathic potential
of aqueous extracts of wheat, black oats and canola and its influence on soybean
germination. The aqueous extracts were obtained by mixing 1g, 5 g and 10 g of the
dry and ground matter of the plants with 99 ml, 95 ml and 90 ml of distilled water,
respectively. There was also a control with only distilled water. The experiment was
conducted in a completely randomized design with four replications. The results
obtained allow us to conclude that the aqueous extracts of oats, canola and wheat
had significant interference on germination, germination rate and radicle size. Black
oats and canola showed more notable results than wheat in relation to the
germination and vigor parameters of soybean. The allelopathic interactions vary
according to the extract concentration.Na regi?o sul do Brasil, as culturas de trigo (Triticum aestivum), aveia preta (Avena
strigosa) e canola (Brassica napus) s?o cultivadas no per?odo de inverno com fun??o
de cobertura do solo e de produ??o de gr?os. Entretanto, n?o h? informa??es sobre
poss?veis intera??es alelop?ticas dessas culturas sobre a soja na Regi?o das
Miss?es, RS. Sendo assim, o objetivo deste trabalho foi avaliar o potencial
alelop?tico de extratos aquosos de trigo, aveia e canola e sua influ?ncia sobre a
germina??o de sementes de soja. Os extratos aquosos foram obtidos pela mistura
de 1 g, 5 g e 10 g de mat?ria seca e triturada das plantas em mistura com 99 ml, 95
ml e 90 ml de ?gua destilada, respectivamente. Tamb?m houve uma testemunha
apenas com ?gua destilada. O experimento foi conduzido em delineamento
inteiramente casualizado, com quatro repeti??es. Os resultados obtidos permitem
concluir que os extratos brutos aquosos de aveia, canola e trigo tiveram interfer?ncia
significativa sobre a germina??o, ?ndice de velocidade de germina??o e tamanho da
rad?cula de soja. A aveia preta e a canola apresentaram efeitos mais percept?veis do
que o trigo em rela??o aos par?metros de germina??o e vigor da soja. As intera??es
alelop?ticas variam de acordo com a concentra??o do extrato
Efeito de diferentes modos de poliniza??o sobre caracter?sticas dos frutos de Physalis peruviana L. (Solanaceae)
Get PDFThe objective of this study was to evaluate the effect of different modes of pollination
on production and fruit quality of Physalis peruviana L. (Solanaceae), a self-
compatible species, pollinated by bees and who also perform self-pollination. The
experiment was conducted in the city of Cerro Largo / RS, using 20 individuals grown
in pots. Pollination treatments were: 1. cross-pollination by hand with emasculated
flowers, 2. self-pollination by hand 3. Natural self-pollination and 4. Open pollination.
60 flowers were used per treatment, and the flowers of the treatments 1, 2 and 3,
bagged in advance button. The following variables were evaluated: Weight, seed
number, diameter, height and number of fruits formed. The results were submitted to
analysis of variance and means compared by the Scott-Knott test, at 5% significance
level. The fruit weight and number of seeds differed significantly in all treatments,
with the highest values recorded in the fruits resulting from cross hand pollination,
followed by open pollination. The diameter and height of fruit did not differ between
the cross-pollination treatments (manual, spontaneous). However, these variables
values were significantly higher in these treatments, when compared to the values
resulting from self-pollination treatments (manual, spontaneous). The number of fruits
formed showed no significant differences among the four pollination treatments.
Considering only the insusceptible pollination treatments occur in the natural
environment, the fruits formed by open pollination were 35% heavier, diameter and
height 17% larger and 56% more seed produced from the treatment of spontaneous
self-pollination. Were found in the flowers of P. peruviana eight species of bees,
representatives of the families Apidae, Colletidae and Halictidaes. The study results
show that cross-pollination results in higher quality fruit of P. peruviana. Yet, although
P. peruviana be able to self-pollination and self-pollination, cross pollination by bees
adds greater economic value to its fruits.O objetivo deste estudo foi avaliar o efeito de diferentes modos de poliniza??o sobre
a produ??o e a qualidade dos frutos de Physalis peruviana L. (Solanaceae), uma
esp?cie autocompat?vel, polinizada por abelhas e que tamb?m realiza
autopoliniza??o. O experimento foi conduzido na cidade de Cerro Largo/RS,
utilizando-se 20 indiv?duos cultivados em vasos. Os tratamentos de poliniza??o
foram: 1. Poliniza??o cruzada manual com flores emasculadas, 2. Autopoliniza??o
manual 3. Autopoliniza??o espont?nea e 4. Poliniza??o aberta. Foram utilizadas 60
flores por tratamento, sendo as flores dos tratamentos 1, 2 e 3, previamente
ensacadas em bot?o. As seguintes vari?veis foram avaliadas: peso, n?mero de
sementes, di?metro, altura e n?mero de frutos formados. Os resultados foram
submetidos ? an?lise de vari?ncia e as m?dias comparadas atrav?s do teste de
Scott-Knott, com ?ndice de signific?ncia de 5%. Os visitantes florais foram
determinados por observa??es focais e coletas de indiv?duos diretamente nas flores
com um total de 30 horas de observa??o e coleta em dias n?o consecutivos. O peso
dos frutos e o n?mero de sementes diferiram significativamente em todos os
tratamentos, sendo os maiores valores verificados nos frutos resultantes de
poliniza??es manuais cruzadas, seguidos dos de poliniza??es abertas. O di?metro e
altura dos frutos n?o diferiram entre os tratamentos de poliniza??o cruzada (manual
e espont?nea). Entretanto, os valores destas vari?veis foram, significativamente,
maiores nestes tratamentos, quando comparados aos valores resultantes dos
tratamentos de autopoliniza??o (manual e espont?nea). O n?mero de frutos
formados n?o apresentou diferen?as significativas entre os quatro tratamentos de
poliniza??o. Considerando-se apenas os tratamentos de poliniza??o passiveis de
ocorrer no ambiente natural, os frutos formados por poliniza??o aberta foram 35%
mais pesados, com di?metro e a altura 17% maiores e com 56% mais sementes
produzidas do que o tratamento de autopoliniza??o espont?nea. Foram verificadas
nas flores de P. peruviana oito esp?cies de abelhas, representantes das fam?lias
Apidae, Colletidae e Halictidaes. Os resultados do estudo evidenciam que a
poliniza??o cruzada resulta em maior qualidade dos frutos de P. peruviana. Ainda,
embora P. peruviana seja apta a autopoliniza??o e autofecunda??o, a poliniza??o
cruzada realizada por abelhas agrega maior valor econ?mico a seus frutos
Biologia reprodutiva e da poliniza??o de Physalis peruviana L.
Get PDFIn this study we described the floral biology of Physalis peruviana L. and investigated
the increase in the number of fruits formed and the quality of these fruits through
interactions with insects and different modes of manual pollination and also the floral
visitors and pollinators. The anthesis was described by measuring floral structures
and observing changes in floral whorls, stigma receptivity and anther dehiscence
over the duration of the flower. The increase in quality and number of fruits formed
was compared between the different modes of manual pollination and control. The
frequency of floral visitors (N = 48h), behavior analysis and pollinator definition were
made through focal observations. The P. peruviana anthesis lasts three days, with
the flower opening and closing each day. During the anthesis, an increase in the size
of the stamens (length) and corolla (diameter) was observed. The receptivity of
stigma occurs before anthers dehiscence and continues throughout the days of
anthesis. The anthers dehiscence is sequential, with an average of three anthers
open on the first, all open on the second day. Nectar was produced throughout the
anthesis, with available volume between 0,1 and 0,2 microliter, and accumulated
volume between 1,8 on the first day and 0,9 microloiter on the third day. The
reproductive success in fruit formation in P. peruviana was superior in open
pollination (88,46%) when compared to cross-pollination (72,2%) and self-pollination
(66,67%). The variables mass, diameter, height and average number of seeds were
significantly higher in open pollination and cross pollination when compared to the
other tests. Apis mellifera was the most frequent bee in flowers with 98,46% (n =
2302) of visits. There was no pollination deficit in P. peruviana, and although the plant
produces fruits by self-pollination, the increase in variables that measure fruit quality
and the number of fruits formed was greater in the open pollination test and cross
pollination. Thus P. peruviana, considered a self-compatible plant, had its production
and fruit quality improved due to the visitation of bees, suggesting that adequate
pollination by these insects should be considered in the management strategies for
this crop.Neste estudo foi descrita a biologia floral de Physalis peruviana L., uma esp?cie
andina com grande potencial econ?mico, e investigado o incremento no n?mero de
frutos formados e na qualidade destes frutos atrav?s de intera??es com insetos e
com diferentes modos de poliniza??o manual, identificados os visitantes florais e os
polinizadores. A descri??o da antese foi feita atrav?s de medidas das estruturas
florais e observa??o das mudan?as nos verticilos, receptividade do estigma e
deisc?ncia das anteras ao longo da dura??o da flor. O incremento na qualidade e no
n?mero de frutos formados foi comparado entre os diferentes modos de poliniza??o
manual e poliniza??o controle. A frequ?ncia dos visitantes florais (N = 48h), an?lise
do comportamento e defini??o dos polinizadores foram feitas atrav?s de
observa??es focais. A antese de P. peruviana dura tr?s dias, com a flor abrindo e
fechando a cada dia. Ao longo da antese foi registrado aumento no tamanho dos
estames (comprimento) e da corola (di?metro). A receptividade do estigma se d?
antes da deisc?ncia das anteras e continua durante todos os dias da antese. A
deisc?ncia das anteras ? sequencial, com n?mero m?dio de tr?s anteras abertas no
primeiro, estando todas abertas no segundo dia. N?ctar foi produzido ao longo de
toda antese, com volume dispon?vel entre 0,1 a 0,2 microlitros, e volume acumulado
entre 1,8 no primeiro dia e 0,9 microlitros no terceiro dia. O sucesso reprodutivo na
forma??o de frutos em P. peruviana foi superior na poliniza??o aberta (88,46%),
quando comparado a poliniza??o cruzada (72,92%) e autopoliniza??o espont?nea
(66,67%). As vari?veis massa, di?metro, altura e n?mero m?dio de sementes foram
significativamente maiores na poliniza??o aberta e na poliniza??o cruzada quando
comparada aos demais testes. Apis mellifera foi a abelha mais frequente nas flores
com 98,46% (n= 2302) das visitas. N?o foi registrado deficit de poliniza??o em P.
peruviana, e embora a planta produza frutos por autopoliniza??o, o incremento nas
vari?veis que medem a qualidade dos frutos e o n?mero de frutos formados foi maior
no teste de poliniza??o aberta e na poliniza??o cruzada. Assim P. peruviana,
considerada uma planta autocompat?vel, teve sua produ??o e qualidade dos frutos
melhorada em virtude da visita??o de abelhas, sugerindo que a adequada
poliniza??o por esses insetos deve ser considerada nas estrat?gias de manejo para
esta cultura
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Revis?o dos estudos dos polinizadores do morangueiro no Brasil
Get PDFThe pollination service by bees has high importance in agriculture, due to the economic value
of pollination in food production. In strawberry, the pollination service by bees is associated
with increased production and improvement of the quality of pseudofruits. Thus, the
objective of this work, presented in the form of literature review, was to address aspects of
strawberry pollination in the productivity and quality of pseudofruits produced. For data
collection, the Web of Science, Scopus, SciELO, Science Direct, Google Scholar databases,
were used, including the Database of the Brazilian Agricultural Research Company (BDPAEmbrapa), from 2000 to 2019. To date, knowledge about the pollination of strawberry in the
country has been obtained through studies carried out in commercial crops and experimental
areas, usually belonging to universities, state agricultural institutions and Embrapa. Studies
of strawberry pollination were carried out mainly in Atlantic Forest environments, with lower
frequency in Pampa, Cerrado and Caatinga, and no studies were found in the Amazon and
the Pantanal. All studies of the biology of strawberry pollination, in a protected environment
were carried out through pollination directed with fat-free bee species of the Meliponinae
Subfamily (Apidae). Apis mellifera bees, Plebeia nigriceps, Tetragonisca angustula,
Nannotrigona testaceicornis, Trigona spinipes, are efficient pollinators of strawberry. The
provision of these agents improves the quality of pseudofruits, mainly by decreasing
deformation, improvements in weight, shape and size, resulting in pseudofruits with higher
commercial value. Little attention is paid to the pollination of strawberry, although studies
show that the provision of pollinators usually results in gains in production, in this sense new
studies are necessary to verify the contribution of each bee species in the increment
production of the different strawberry cultivarsO servi?o de poliniza??o por abelhas apresenta elevada import?ncia na agricultura. No
morangueiro, a poliniza??o por abelhas est? associada ao aumento da produ??o e melhoria
da qualidade dos pseudofrutos. Assim, o objetivo deste trabalho, apresentado na forma de
revis?o de literatura, foi abordar aspectos da poliniza??o do morangueiro na produtividade e
qualidade dos pseudofrutos produzidos. Para a coleta de dados foram utilizadas as bases Web
of Science, Scopus, SciELO, Science Direct, Google Acad?mico, incluindo a Base de Dados
da Empresa Brasileira de Pesquisa Agropecu?ria (BDPA-Embrapa), no per?odo de 2000 a
2019. At? o momento, o conhecimento sobre a poliniza??o do morangueiro no pa?s foi obtido
por meio de estudos executados em cultivos comerciais e em ?reas experimentais, geralmente
pertencentes a universidades, institui??es agropecu?rias estaduais e a Embrapa. Os estudos
da poliniza??o de morangueiro foram efetuados principalmente em ambientes de Mata
Atl?ntica, com menor frequ?ncia no Pampa, Cerrado e Caatinga, n?o sendo encontrados
estudos na Amaz?nia e no Pantanal. A totalidade dos estudos da biologia da poliniza??o do
morangueiro, em ambiente protegido foram realizados atrav?s de poliniza??o dirigida com
esp?cies de abelhas sem ferr?o da Subfam?lia Meliponinae (Apidae). As abelhas Apis
mellifera, Plebeia nigriceps, Tetragonisca angustula, Nannotrigona testaceicornis, Trigona
spinipes, s?o polinizadores eficientes do morangueiro. A provis?o desses agentes melhora a
qualidade dos pseudofrutos, principalmente pela diminui??o da deforma??o, melhorias no
peso, formato e tamanho, resultando em pseudofrutos com maior valor comercia
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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