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Biology of Grapsus grapsus (LINNAEUS, 1758) (Brachyura, Grapsidae) in the Saint Peter and Saint Paul Archipelago, Equatorial Atlantic Ocean

Freire, A. S.; Pinheiro, M. A. A.; Karam-Silva, H.; Teschima, M. M.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 263-273
Português
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37.646208%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Eleven expeditions were undertaken to the Saint Peter and Saint Paul Archipelago to study the reproductive biology of Grapsus grapsus, providing additional information on limb mutilation and carapace colour. MATURE software was used to estimate morphological maturity, while gonadal analyses were conducted to estimate physiological maturity. The puberty moult took place at larger size in males (51.4 mm of carapace length) than in females (33.8 mm), while physiological maturity occurred at a similar size in males (38.4 mm) and in females (33.4 mm). Above 50 mm, the proportion of red males increased in the population, indicating that functional maturity is also related to colour pattern. Small habitat and high local population density contributed to the high rate of cannibalism. The low diversity of food items, absence of predators of large crabs and high geographic isolation are the determinants of unique behavioural and biological characteristics observed in the G. grapsus population.

Relationship of black layer and milk line development on maize seed maturity

Vieira, Roberval Daiton; Minohara, L.; Carvalho, N.M. de; Bergamaschi, M.C.M.
Fonte: Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ) Publicador: Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ)
Tipo: Artigo de Revista Científica Formato: 142-147
Português
Relevância na Pesquisa
37.646208%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); A relação entre o desenvolvimento da camada negra e da linha de transformação em amido e a maturidade fisiológica de sementes de milho foi estudada durante dois anos agrícolas (1990/91 e 1991/92). Para atingir os objetivos do trabalho, avaliou-se o grau de umidade, a germinação, o vigor (envelhecimento acelerado, teste frio e condutividade elétrica) e o desenvolvimento da camada negra e da linha de transformação em amido para dois genótipos (CX 133 e IAC 100). Com base nos resultados de germinação e vigor das sementes verificou-se que a maturidade fisiológica foi alcançada antes do estádio 4. Por outro lado, graus de umidade de 30 a 35% foram alcançados somente no estádio de desenvolvimento 4. A linha de transformação em amido provou ser um instrumento útil para predizer a maturidade fisiológica e de colheita para sementes de milho.; The relationship of black layer and milk line development on maize seed maturity was evaluated under tropical conditions. Seed moisture (g.kg-1), standard germination - SG (7 days, 25°C), and vigor, using accelerated aging-AA (96 hours, 42°C and 100% of RH), cold test-CT only in 1991/92 (7 days at 10°C and 7 days at 25°C) and electrical conductivity-EC (four 50-seed samples...

Sexual maturity of the speckled swimming crab Arenaeus cribrarius (Lamarck, 1818) (Decapoda, Brachyura, Portunidae), in the Ubatuba Littoral, São Paulo state, Brazil

Pinheiro, MAA; Fransozo, A.
Fonte: Brill Academic Publishers Publicador: Brill Academic Publishers
Tipo: Artigo de Revista Científica Formato: 434-452
Português
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The sizes at morphological and physiological maturity of male and female Arenaeus cribrarius were estimated to determine if both events are synchronous. Animals were captured with otto-trawls at Ubatuba, Brazil. A total of 2356 specimens, 977 males and 1379 females, were obtained. The major carapace width without spines (CW), the propodus length of the major cheliped (PL) and the width of the 5th abdominal somite (AW) were measured with vernier calipers. Allometric relationships and gonadal development were analyzed to determine the maturity in both sexes. The size at the onset of male morphological maturity was estimated at CW 52 mm, smaller than the CW 63.4 mm physiological maturity size observed. For females, these events are synchronous since both estimates converged at CW 59.7 mm. The onset of functional sexual maturity in A. cribrarius at CW 63.4 and 59.7 mm in males and females, respectively, would indicate a minimum size of CW 64 mm for fishing purposes. Differences between allometric and gonadal estimates indicate the importance of considering both methods. A comparison of the present results with other available data in portunid crabs is provided.

Sexual maturity of Eurytium limosum (say 1818) from a subtropical mangrove in Brazil

Guimaraes, F. J.; Negreiros-Fransozo, M. L.; EscobarBriones, E.; Alvarez, F.
Fonte: Kluwer Academic/plenum Publ Publicador: Kluwer Academic/plenum Publ
Tipo: Conferência ou Objeto de Conferência Formato: 157-161
Português
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The size at onset of maturity of Eurytium limosum from a subtropical mangrove in Brazil was investigated. In this species, sexual maturity for males can be indicated by the allometric growth and gonopod length. For females, the morphological sexual maturity can only be externally verified through the relative quantity of setae along the abdominal margins and pleopods. Internally, gonad development was also examined. The size at which half of the population is physiologically mature was 11.6 mm of CW for females and 12.3 mm of CW for males. The values for the morphological and physiological maturity are very similar, indicating that the development of the secondary sexual characters is synchronized with the achievement of the physiological maturity for E. limosum.

Physiological maturity and relationships of growth and reproduction in the red mangrove crab Goniopsis cruentata (Latreille) (Brachyura, Grapsidae) on the coast of São Paulo, Brazil

Cobo, Valter José; Fransozo, Adilson
Fonte: Sociedade Brasileira de Zoologia Publicador: Sociedade Brasileira de Zoologia
Tipo: Artigo de Revista Científica Formato: 219-223
Português
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47.44568%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Este trabalho fornece informações sobre as relações entre a maturidade sexual e o crescimento do caranguejo Goniopsis cruentata (Latreille, 1803). Durante o período de janeiro de 1995 a dezembro de 1996 foram realizadas coletas mensais na região de Ubatuba, litoral norte do Estado de São Paulo. Os animais capturados foram reunidos em quatro grupos de interesse: macho jovem, macho adulto, fêmea jovem e fêmea adulta, em que estão incluídas as ovígeras. Para cada animal foi mensurada a largura da carapaça (LC) e anotadas a condição de muda e o estágio do desenvolvimento gonadal. A maturidade fisiológica foi observada entre 21.4 e 23.7mmLC para ambos os sexos. A população amostrada apresentou atividade de muda em todas as classes de tamanho durante todo o período estudado, o que sugere o estabelecimento de um padrão de crescimento contínuo e ausência de anecdise terminal para essa espécie. Esse fato pode estar associado com a habilidade desses animais em copular durante a intermuda, gerando uma grande quantidade de indivíduos maduros durante todo o ano, garantindo a continuidade do processo reprodutivo.; This investigation provided information on the physiological sexual maturity and relationships of growth and reproduction in Goniopsis cruentata (Latreille...

Comportamento de cultivares de soja quanto a qualidade fisiológica de sementes

Vieira, Roberval Daiton; Minohara, Luciane; Panobianco, Maristela; Bergamaschi, Mônika Carneiro Meira; Mauro, Antônio Orlando
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 123-130
Português
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This work was carried out in order to evaluate if there was a relationship between genotypes and the physiological soybean (Glycine max L.) seed quality. It was conducted during three years using seven cultivars each year. The seeds were harvested at: 1) yellow radicle or expanded pod stage, 2) yellow pod or physiological maturity (R7), 3) harvest maturity (R8), and 4) R8 + 21 days delay. Seed moisture content, standard germination, and vigor tests were performed. The germination and vigor evaluated by accelerated aging and electrical conductivity did not show physiological seed quality differences among genotypes as harvested at physiological maturity. Then, the evaluation of seed germination and vigor, when the environment is not a considered factor, is not an efficient method to show differences among soybean genotypes in terms of seed quality.; O presente trabalho teve como objetivo estudar a qualidade fisiológica de sementes de soja (Glycine max L.), em diferentes estádios de desenvolvimento, visando identificar diferenças que pudessem ser atribuídas às características genéticas da planta, usando-se três tradicionais métodos para avaliação da germinação e vigor de sementes. O experimento foi instalado e conduzido durante três anos agrícolas...

Maturidade fisiológica das sementes do ipê amarelo, Tabebuia chrysotricha (Mart. Ex DC.) Standl

Fonseca, Fernanda Lopes; Menegario, Cristiane; Mori, Edson Seizo; Nakagawa, João
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 136-141
Português
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Ipê amarelo Tabebuia chrysotricha (Mart. Ex DC.) Standl. is a native forest species that presents heavy and durable wood: it is common to be used for urban arborization. The species is latte secondary and heliophyta. Occurs from Espirito Santo State until Santa Catarina in the Pluvial Atlantic Forest (Mata Atlântica). The seedling production is hard because their seeds have short longevity after dispersion, and so due to the difficulty to harvest winged seeds that are quickly dispersed by the wind. The present study was carried out to evaluate the physiological maturity of Ipê Amarelo seeds, to establish the best moment to harvest them. The study was to accompany the maturation of 100 fruits in just beginning development, from eleven different trees. Morphological characteristic measures were made weekly, with fruits still on trees, starting from the second week development when fruits presented the following averages: 6.3 cm length, 0.71 cm thickness, and 0.82 cm width. From the sixth week of fruit development we harvest them to proceed the germination test, water content rate, and electric conductivity test. The germination has begun by the seventh week development with 28% of germinated seedlings. The highest germination rate happened by the eighth week development...

Physiological maturity of Cnidosculus quercifolius Pax & K. Hoffm. seeds

De Medeiros Silva, Lígia Maria; De Aguiar, Ivor Bergemann; Matos, Valderez Pontes; Viégas, Ricardo Almeida; De Mendonça, Izaque Francisco Candeia
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 15-20
Português
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Cnidosculus quercifolius (Euphorbiaceae) is an important tree species native from the semi-arid region of the northeastern Brazil. Physiological maturity of seeds was studied in order to establish indices to determine the best time for fruit collection. Fruits were weekly collected from 30 to 72 days after flowering, and features such as color, size, both fresh and dry mass and dehiscence were observed. Extracted seeds were analyzed regarding the color, moisture content, germination and vigor. The results showed that color, size and fresh mass of fruits were not able to predict seed maturity. Seed physiological maturity occurred 65 days after flowering, when higher values of fruit dry mass, as well as seed germination and vigor were found. At this time seed moisture content was 22.7%. The fruit exocarp was coiled, but remained adhered to the endocarp; this feature represents an effective and practical visual indicator of collection time. Seeds are released in an explosive way by natural dehiscence after 72 days of flowering.

Physiological maturity of fruits and seeds of Poincianella pyramidalis (Tul.) L.P. Queiroz

Lima,Cosmo Rufino de; Bruno,Riselane de Lucena Alcântara; Silva,Katiane da Rosa Gomes da; Pacheco,Mauro Vasconcelos; Alves,Edna Ursulino; Andrade,Albericio Pereira de
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 Português
Relevância na Pesquisa
57.692593%
The Leguminosae family is one of the most representative botanical families of the Caatinga, with 80 endemic species, highlighting the catingueira (Poincianella pyramidalis). The objective of this research work was to study the maturation process of P. pyramidalis seeds based on the physiological maturity. Five harvest of fruits and seeds were carried out, with 15 days interval each, in a period from July to September 2010. The harvests began 75 days after anthesis (d.a.a.) and lasted until 135 d.a.a. Fruits and seeds were subjected to the following assessments: size, moisture content, and dry mass of fruits and seeds; and germination and vigor of seeds (first count of germination, germination speed index, length and dry mass of seedling). Under the environmental conditions of municipality of Soledade, State of Paraiba, Northeast Brazil, the point of physiological maturity of P. pyramidalis seeds occurs at 125 d.a.a., when the maximum accumulation of dry mass is 1.993 g and moisture content is 21%. The ideal point of harvest is between 130 d.a.a and 135 d.a.a., before natural dehiscence, when the moisture content of seeds is between 13.0% and 5.0%.

Physiological maturity of eggplant seeds

Martins,Denize Carvalho; Vilela,Fernanda Keila Junqueira; Guimarães,Renato Mendes; Gomes,Luiz Antônio Augusto; Silva,Priscila Alves da
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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47.378784%
Determination of seed physiological maturity and ideal moment for harvesting fruits to extract their seeds are important aspects to produce seeds with high quality. To identify the best period for harvesting eggplant fruits, associated with ideal resting period of the fruit for extracting seeds, an eggplant production field was installed in municipality of Ijaci, in the State of Minas Gerais, Southwestern Brazil. The fruits were harvested at periods of 49, 56, 63, 70, and 77 days after pollination (DAP). The seeds of fruits harvested in each period were manually extracted immediately after harvest or after a post-harvest resting period of seven days, under a shed. The physiological quality of seeds was assessed by tests of: germination percentage; germination and emergence speed indexes; and electrical conductivity; which were carried out in the Central Seed Laboratory, Federal University of Lavras. Electrophoretic analyses of isoenzymes: catalase (CAT); esterase (EST); superoxide dismutase (SOD); and peroxidase (PO), were also therein performed. Results of germination and vigor of seeds have showed that the best period for harvesting the fruit is around 70 DAP; and that seeds should be extracted immediately after harvest. Electrophoretic analysis of enzymes has showed immaturity for eggplant seeds...

Physiological maturity and relationships of growth and reproduction in the red mangrove crab Goniopsis cruentata (Latreille) (Brachyura, Grapsidae) on the coast of São Paulo, Brazil

Cobo,Valter José; Fransozo,Adilson
Fonte: Sociedade Brasileira de Zoologia Publicador: Sociedade Brasileira de Zoologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2005 Português
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47.44568%
This investigation provided information on the physiological sexual maturity and relationships of growth and reproduction in Goniopsis cruentata (Latreille, 1803). Collections were made monthly from January 1995 through December 1996, on the northeastern coast of São Paulo State, Brazil. The crabs were grouped into juvenile males; adult males; juvenile females, and adult females, including ovigerous ones. For each specimen the carapace width (CW) was measured, and molt condition and macroscopic developmental stage of the gonad tissue were recorded. CWs of physiologically mature crabs were between 21.4 and 23.7 mm for both sexes. This population showed molt activity in all size groups throughout the study period, which suggests continuous growth and the absence of terminal anecdysis. This may be associated with the ability of these animals to copulate during the intermolt, supplying a high proportion of mature individuals over time and ensuring continuity of reproduction year-round.

Relationship of black layer and milk line development on maize seed maturity

Vieira,R.D.; Minohara,L.; Carvalho,N.M. de; Bergamaschi,M.C.M.
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/1995 Português
Relevância na Pesquisa
37.646208%
The relationship of black layer and milk line development on maize seed maturity was evaluated under tropical conditions. Seed moisture (g.kg-1), standard germination - SG (7 days, 25°C), and vigor, using accelerated aging-AA (96 hours, 42°C and 100% of RH), cold test-CT only in 1991/92 (7 days at 10°C and 7 days at 25°C) and electrical conductivity-EC (four 50-seed samples, 24 hours imbibition at 25°C) and milk line and black layer formation (using a five-stage rating system) were determined at 3 to 4 days intervals, using two genotypes (hybrid CX 133 and variety IAC 100) during the crop seasons of 1990/91 and 1991/92. The results showed that physiological maturity was reached before stage 4, based on seed germination and vigor (AA and CT) values, which occurred before that stage and presented the lowest values of EC. On the other hand, moisture content levels of 300 to 350 g.kg-1 were reached only at stage 4. The milk line ratings proved useful in predicting physiological maturity as well as the harvest maturity.

Sexual maturity and reproductive period of the swimming blue crab Callinectes danae Smith, 1869 (Brachyura: Portunidae) from Guaratuba Bay, Paraná State, southern Brazil

Marochi,Murilo Zanetti; Moreto,Thaís Fernanda; Lacerda,Mariana Baptista; Trevisan,André; Masunari,Setuko
Fonte: Sociedade Brasileira de Carcinologia Publicador: Sociedade Brasileira de Carcinologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 Português
Relevância na Pesquisa
58.0171%
This work aims to estimate the average size at the onset of morphological and physiological sexual maturity and the reproductive period of Callinectes danae. Specimens were captured from a shrimp fishing boat equipped with a trawl net from March 2009 to February 2010. After sorting, crabs were sexed, and the following morphometric dimensions were measured: carapace width (CW), length and height of the major (MAP and HMAP), and the minor cheliped propodus (MIP and HMIP) for both sexes, and the abdominal width for females (AW). The onset of morphological maturity was estimated with the REGRANS program, in which the inflection point is calculated. The size at the onset of physiological maturity was determined by logistic regressions fitted to the relationships between the percentages of juvenile and adult individuals of each CW. A total of 893 individuals were sampled. Of these individuals, 389 were males, 472 non-ovigerous females, and 32 ovigerous females. The CW ranged from 19.81 to 117.17 mm for males, 19.91 to 113.11 mm for non-ovigerous females, and 70.55 to 88.60 mm for ovigerous females. Morphological sexual maturity was attained at 86.47 mm CW (males) and 67.87 mm CW (females). The size at the onset of physiological maturity was calculated to be 86.50 mm CW (males) and 67.00 mm CW (females). Due to the closeness of these values...

Maturation of seeds of Caesalpinia echinata Lam. (Brazilwood), an endangered leguminous tree from the Brazilian Atlantic Forest

Borges,Igor Ferrari; Giudice Neto,João Del; Bilia,Denise Augusta Camargo; Figueiredo-Ribeiro,Rita de Cássia Leone; Barbedo,Claudio José
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2005 Português
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47.251416%
The present work describes changes during the maturation process of seeds of Caesalpinia echinata Lam. Individual flowers were tagged in the day of their anthesis and the pods were collected directly from the branches from 32 to 65 days after flowering (DAF). Results obtained suggested that physiological maturity of C. echinata seeds occurred ca. 60-65 DAF, immediately before shedding, when seeds had 30-40% water content.

Modelling maize grain moisture content during maturation and post-maturity dry-down

MAIORANO ANDREA; DONATELLI Marcello
Fonte: Department of Agricultural Sciences, University of Helsinki Publicador: Department of Agricultural Sciences, University of Helsinki
Tipo: Articles in periodicals and books Formato: Printed
Português
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38.05906%
Maize grain moisture content during maturation and post-maturity dry-down are very important factors influencing harvest and post-harvest management, and the technological and safety of maize grain: it influences the harvest timing and the consequent drying process and drying costs, the feeding activity of some maize borers, and the development of toxigenic fungi. Thus, an improved understanding of the process of moisture loss during maize grain development would allow: i) to assess risk regarding weather factors that may impede harvest timing, ii) to evaluate the costs associated with an increased need for mechanical drying, iii) a better understanding of maize development during the field phase and the relationships with insect pests and diseases development. Development of maize in the field can be partitioned into three phases: i) lag phase, ii) grain filling and maturation drying, iii) and post-maturity dry-down. The lag phase is characterized by a rapid increase in moisture content. During the grain filling and maturation drying phase moisture content decreases almost linearly until the reaching of physiological maturity. During post-maturity dry-down, moisture content decrease primarily due to water loss from the kernel. Starting from the available knowledge about maize seeds development and maturation...

Metabolic maturity and vigour in neonatal lambs, and subsequent impacts on thermoregulation and survival.

Plush, Kate Joanna
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014 Português
Relevância na Pesquisa
47.96157%
Lamb mortality in Australia averages approximately 20%, representing a major constraint to the profitability of sheep enterprises and compromised animal welfare. Most postpartum lamb loss occurs within the first three days of life and is largely caused by starvation, exposure to cold conditions and mismothering from the ewe. In this thesis we developed an over-arching hypothesis that differences in metabolic or physiological maturity exist between lambs, and that these differences relate to early postnatal vigour and survival, particularly during exposure to cold conditions. To test this hypothesis, behaviour associated with initial vigour was quantified in breeds of sheep which differ widely in neonatal survival and more specifically, risk of hypothermia. Pre-suckling blood samples were collected from these animals in order to identify potential markers of maturity chosen to represent the hypothalamic- pituitary- adrenal (HPA) axis, renal function and energy metabolism. A number of metabolite and endocrine shifts were identified in those that were quicker to reach the udder of the ewe and begin sucking. Namely, creatine, non-esterified fatty acids, leptin and ghrelin concentrations were elevated, implying these individuals may be better able to regulate energy mobilisation soon after birth. Lamb vigour was also strongly associated with rectal temperature at birth...

Maturação fisiológica e taxa de cruzamento natural na produção de sementes de Capsicum; Physiological maturity and natural rate crossing in seed production of Capsicum

Justino, Elaine Vaz
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
Português
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em Agronomia, 2014; A implantação de um campo de produção de qualquer espécie de planta propagada sexuadamente, como as pimentas do gênero Capsicum deve ser feita empregando sementes de alta qualidade. A qualidade é uma característica multifatorial representada pela soma dos atributos físicos, fisiológicos, genéticos e sanitários, através do qual as sementes expressam toda sua potencialidade em um determinado ambiente. A semente é, portanto, um insumo de grande proeminência no processo produtivo. O objetivo deste trabalho foi avaliar a qualidade fisiológica e genética das sementes de espécies de Capsicum por meio, respectivamente de estudos relacionados com a determinação da maturidade fisiológica das sementes e com a taxa de cruzamento natural. O trabalho foi conduzido nas instalações do campo experimental e laboratórios de sementes, de pós-colheita, de melhoramento genético e de análise genômica da Embrapa Hortaliças Brasília-DF. Para a determinação da maturidade fisiológica das sementes foi utilizada a cv. BRS Mari (C. baccatum var. pendulum). As sementes foram obtidas de frutos colhidos em diferentes estádios de maturação...

Dissecting the genetic basis of physiological processes determining maize kernel weight using a RIL population.

Alvarez Prado, Santiago; Lopez, Cesar Gabriel; Gambin, Brenda Laura; Abertondo, Victor; Borras, Lucas
Fonte: Elsevier Science Bv Publicador: Elsevier Science Bv
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Português
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57.510264%
Knowledge on the genetic bases of physiological processes determining maize kernel weight (KW) is relevant for maize yield improvement. However, little is known about the genetic control of KW and its component traits: kernel growth rate (KGR) and grain-filling duration (GFD). We phenotyped several grain-filling traits in 245 RILs from the IBM Syn4 population (B73×Mo17) under two environments, and a multi-trait multi-environment quantitative trait loci (QTL) analysis was conducted. We were specifically interested inseeking genetic links of knowncorrelated traits atthe phenotypic level, like kernelmaximum water content(MWC) and KGR. Our specific objectives were (i)to conduct a QTL analysis over grain-filling traits to determine their genetic complexity,(ii)to study the relationships between kernel developmental traits at phenotypic and genetic levels, and (iii) to suggest possible candidate genes for each specific trait using detected QTL and B73 sequence data. All traits showed significant genotype × environment interactions (p < 0.001) and large phenotypic variability. KW variability was positively associated (p < 0.01) with variations in KGR (r = 0.79) and GFD (r = 0.32). As expected, KGR was positively correlated to MWC, while GFD was negatively correlated to the kernel moisture concentration at physiological maturity (MCPM). A total of 10 joint QTL were detected under both environments...

Independent genetic control of maize (Zea mays L.) kernel weight determination and its phenotypic plasticity

Prado, S.A.; Sadras, V.O.; Borrás, L.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
47.251416%
Maize kernel weight (KW) is associated with the duration of the grain-filling period (GFD) and the rate of kernel biomass accumulation (KGR). It is also related to the dynamics of water and hence is physiologically linked to the maximum kernel water content (MWC), kernel desiccation rate (KDR), and moisture concentration at physiological maturity (MCPM). This work proposed that principles of phenotypic plasticity can help to consolidated the understanding of the environmental modulation and genetic control of these traits. For that purpose, a maize population of 245 recombinant inbred lines (RILs) was grown under different environmental conditions. Trait plasticity was calculated as the ratio of the variance of each RIL to the overall phenotypic variance of the population of RILs. This work found a hierarchy of plasticities: KDR ≈ GFD > MCPM > KGR > KW > MWC. There was no phenotypic and genetic correlation between traits per se and trait plasticities. MWC, the trait with the lowest plasticity, was the exception because common quantitative trait loci were found for the trait and its plasticity. Independent genetic control of a trait per se and genetic control of its plasticity is a condition for the independent evolution of traits and their plasticities. This allows breeders potentially to select for high or low plasticity in combination with high or low values of economically relevant traits.; Santiago Alvarez Prado...

Fruit development of two high oleic safflower (Carthamus tinctorius L.) cultivars

Franchini,MC; Flemmer,AC; Lindström,LI; David,MA; Fernandez,PA
Fonte: Phyton (Buenos Aires) Publicador: Phyton (Buenos Aires)
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
Relevância na Pesquisa
47.770977%
The purpose of this study was to describe fruit development in two high oleic safflower (Carthamus tinctorius L.) cultivars during four growing seasons. Pericarp histogenesis, and dynamics of pericarp and seed dry weight and fruit water content were studied. The dynamics of the pericarp and seed growth was similar between cultivars and years. The pericarp completed its growth before the seed. Pericarp potential size was already set at anthesis as no cell division was observed at this time. Maximum pericarp dry weight was achieved 8 days after anthesis, when cell wall lignification concluded. At this time, twinned prismatic simetric crystals had decreased in number and size respect to those observed at anthesis. Physiological maturity (maximum seed dry weight) was achieved between 17 and 25 days after anthesis. Similar pericarp growth rate and duration between cultivars and years were associated to similar maximum pericarp dry weight (17 mg), except in 2012. In this year, the higher maximum pericarp dry weight (20 mg) was only associated to a higher fruit volume (50 μL). Maximum seed dry weight (22 mg) was lower in CW88 OL than in CW99 OL, except in 2012. However, seed growth rate and time of physiological maturity were similar between cultivars. Fruit water content at physiological maturity (39%) was similar between cultivars. The recommended moisture (10-13%) at harvesting was achieved around 33 days after anthesis. The timing of the different morphological and histological events of safflower fruit development presented in this work sets a not-yet-existent conceptual framework...