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1.
Ciênc. rural (Online) ; 52(8): e20210353, 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1360340

Resumo

The present study aimed to evaluate the developmental phases of feijoa fruits associated with infestation by Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) and the nonpreference of fruit flies for ripe fruits of feijoa. Two tests were carried out. In the first trial, we evaluated the association between the developmental stages of feijoa fruits and infestation by A. fraterculus. To accomplish this, fruits at five different stages of development, from green to ripe, were examined from the Alcântara cultivar. In the second trial, we evaluated the nonpreference of A. fraterculus for ripe fruits of Alcântara, Helena, Mattos and access 2316 cultivars. Physicochemical analyses were performed on the fruits of both trials. In the second test, analyses of polyphenol index and tannin concentration were also performed. Feijoa fruits in stage I are the likely targets of attack by A. fraterculus. The fruits of Alcântara cultivar from stage II, with 39 mm of transversal diameter and soluble solids, presented four puparium / fruit. The fruits of Alcântara and access 2316 cultivars showed greater and lesser infestation, respectively. The fruits of access 2316 also showed a higher concentration of tannins compared to the three commercial cultivars tested, which may have conferred the greatest protection against infestation by A. fraterculus. Feijoa fruits from Alcântara and Mattos cultivars showed high susceptibility to infestation by A. fraterculus, requiring management practices to guarantee commercial production.


O presente estudo teve como objetivos avaliar as fases de desenvolvimento de frutos de feijoa associadas à infestação por Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) e a não preferência por frutos maduros. No primeiro ensaio, foi avaliado a influência dos cinco estágios de desenvolvimento dos frutos de feijoa na infestação por A. fraterculus na cultivar Alcântara. No segundo ensaio, foi avaliado a não preferência de A. fraterculus por frutos maduros das cultivares Alcântara, Helena, Mattos e acesso 2316. Foram realizadas análises físico-químicas nos frutos de ambos os ensaios. No segundo ensaio, também foram realizadas análises do índice de polifenóis e concentração de taninos. Frutos de feijoa no estágio I são os prováveis alvos de ataque por A fraterculus. Os frutos do cultivar Alcântara, a partir do estádio II, quando apresentavam 39 mm de diâmetro transversal e sólidos solúveis, apresentaram quatro pupários/fruto. Os frutos da cultivar Alcântara e do acesso 2316 apresentaram maior e menor infestação, respectivamente. Os frutos do acesso 2316 também apresentaram a maior concentração de taninos do que nas três cultivares comerciais testadas, o que pode ter conferido a maior proteção contra infestação por A. fraterculus. Frutos de feijoa das cultivares Alcântara e Mattos apresentaram alta suscetibilidade à infestação por A. fraterculus, o que requer práticas de manejo para garantir a produção comercial.


Assuntos
Taninos/análise , Tephritidae , Feijoa/crescimento & desenvolvimento
2.
Ci. Rural ; 51(5)2021. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-31339

Resumo

Family farmers preserve the tradition of cultivating maize landrace varieties because these plants have characteristics that hybrids lack. The greatest challenge in conserving in situ on-farm genetic diversity is avoiding gene flow and genetic introgression of transgenes to landrace varieties. Thus, farmers are obliged to change sowing times to guarantee temporal isolation since most farms are small, making spatial isolation impossible. The objective of the present work was to evaluate the behavior of maize landrace varieties submitted to different sowing times and densities in an agroecological system. The test was conducted in sub-sub-divided plots, where the main plot was represented by the sowing time, the sub-plot by the genotype, and the sub-sub-plot by the density, with three replications, for two consecutive years. The results demonstrate the effect of sowing time and density on the characteristics evaluated. In western Santa Catarina, the best time to sow seeds of maize landrace varieties in an agroecological system is in September, which is when the varieties expressed the greatest potential at densities from 45,000 to 50,000 pl.ha-1 , but it will not avoid transgene contamination.(AU)


Famílias camponesas preservaram a tradição do cultivo das variedades crioulas de milho estimuladas por características que os híbridos não apresentam. Sendo, o maior desafio para a conservação da diversidade genética in situ on farm evitar o fluxo gênico e a introgressão genética de trangenes nas variedades crioulas. Nesse sentido, os agricultores são obrigados a alterar épocas de semeadura para garantir isolamento temporal uma vez que a maioria das áreas é pequena inviabilizando o isolamento no espaço. O objetivo do presente trabalho foi avaliar o comportamento de variedades crioulas de milho em sistema de base agroecológica submetidas às diferentes épocas e densidades de semeadura. No ensaio conduzido em parcelas sub-sub-divididas, a parcela principal foi representada pela época, a sub-parcela pelo genótipo e a sub-sub-parcela pela densidade, com três repetições, por dois anos consecutivos. Os resultados demostraram efeito de época e densidade de semeadura nas características avaliadas. É possível indicar que a época mais adequada para semeadura de variedades crioulas de milho em sistema de base agroecológica é em setembro para o oeste de Santa Catarina, sendo que para essa época as variedades expressaram maior potencial de produtividade de grãos na faixa de densidade de 45000 a 50000 pl.ha-1 , mas não impedirá a contaminação por transgene.(AU)


Assuntos
Zea mays/crescimento & desenvolvimento , Zea mays/genética , Agricultura Sustentável/métodos
3.
Acta sci., Biol. sci ; 41: e46667, 20190000. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460893

Resumo

Escobedia grandiflora(L.f.) Kuntze is a wild hemiparasitic plant with orange roots. Little is known about the development of initial parasitism with the host, despite the significant value of roots for Central and South American communities. Therefore, this study aimed to characterize post-seminal structure and development of E. grandiflorain Pennisetum purpureumhost. To analyze the structure and development of E. grandiflora, seedlings, stems and roots samples were processed and examined underlight, confocal and scanning electron microscopy. Escobedia grandifloraseeds are composed of seed coat, perisperm, and embryo. Emergence of the radicle began eleven days after imbibition. Seedlings showed a root hair collar encircling the axis at the root-hypocotyl junction with elongation of internal cortical cells. Seedlings formed haustoria and successfully reached of the host roots 22 days following root emergence. In the root many starch grains were observed, albeit more scarce in the hypocotyl. After 43 days of root emergence, the seedling stage was finished with the formation of the definitive leaves, and star of the plant stage. After 64 days, root ramification, amount of starch, and orange pigmentation increased with formation of haustoria. The developmental pattern of E. grandiflora plants was slow, but the roots grew faster than the stem. Escobedia grandifloraseeds were not endospermic and have limited nutritional value. After root emergence, the young seedling must develop roots and starch storage towards to haustorium formation and attachment to host roots.


Assuntos
Análise do Sêmen , Orobanchaceae/parasitologia , Raízes de Plantas , Sementes
4.
Ciênc. rural (Online) ; 47(6): 01-07, jun. 2017. tab
Artigo em Inglês | VETINDEX | ID: biblio-1479977

Resumo

The objective of this paper was to identify the direct and indirect effects of feijoa fruits (Acca sellowiana) traitson pulp weight, in order to use these traits in indirect genotypes selection. Fruits of five feijoa plants were collected in Rio Grande do Sul, in the years of 2009, 2010 and 2011. Six traits were evaluated: diameter, length, total weight, pulp weight, peel thickness and number of seeds per fruit. In the path analysis, with or without ridge regression, pulp weight was considered as the basic variable, and the other traits were considered as explanatory variables. Total weight and fruit diameter had high direct effect, and are the main traits associated with pulp weight. These traits may serve as criteria for indirect selection to increase feijoa pulp weight, since they are easy to be measured.


O objetivo deste trabalho foi identificar os efeitos diretos e indiretos de caracteres dos frutos de goiabeira-serrana (Accasellowiana) sobre o peso de polpa, visando à utilização desses caracteres para a seleção indireta de genótipos. Foram coletados frutos de cinco grupo de plantas de goiabeira-serrana no Rio Grande do Sul, nos anos de 2009, 2010 e 2011. Seis caracteres foram avaliados: diâmetro, comprimento, peso total, peso de polpa, espessura da casca e número de sementes por fruto. Na análise de trilha com e sem regressão em crista para controle da multicolinearidade, o peso de polpa foi considerado variável básica e os demais caracteres considerados explicativos. O peso total, seguido do diâmetro de fruto, tiveram efeito direto elevado e são os principais caracteres associados ao peso de polpa. Estes caracteres podem servir de critérios de seleção indireta para aumentar o peso de polpa de goiabeira-serrana, pois são de fácil mensuração.


Assuntos
Feijoa/anatomia & histologia , Feijoa/crescimento & desenvolvimento , Pesos e Medidas , Frutas/anatomia & histologia , Seleção Genética
5.
Ci. Rural ; 47(6): 01-07, jun. 2017. tab
Artigo em Inglês | VETINDEX | ID: vti-688119

Resumo

The objective of this paper was to identify the direct and indirect effects of feijoa fruits (Acca sellowiana) traitson pulp weight, in order to use these traits in indirect genotypes selection. Fruits of five feijoa plants were collected in Rio Grande do Sul, in the years of 2009, 2010 and 2011. Six traits were evaluated: diameter, length, total weight, pulp weight, peel thickness and number of seeds per fruit. In the path analysis, with or without ridge regression, pulp weight was considered as the basic variable, and the other traits were considered as explanatory variables. Total weight and fruit diameter had high direct effect, and are the main traits associated with pulp weight. These traits may serve as criteria for indirect selection to increase feijoa pulp weight, since they are easy to be measured.(AU)


O objetivo deste trabalho foi identificar os efeitos diretos e indiretos de caracteres dos frutos de goiabeira-serrana (Accasellowiana) sobre o peso de polpa, visando à utilização desses caracteres para a seleção indireta de genótipos. Foram coletados frutos de cinco grupo de plantas de goiabeira-serrana no Rio Grande do Sul, nos anos de 2009, 2010 e 2011. Seis caracteres foram avaliados: diâmetro, comprimento, peso total, peso de polpa, espessura da casca e número de sementes por fruto. Na análise de trilha com e sem regressão em crista para controle da multicolinearidade, o peso de polpa foi considerado variável básica e os demais caracteres considerados explicativos. O peso total, seguido do diâmetro de fruto, tiveram efeito direto elevado e são os principais caracteres associados ao peso de polpa. Estes caracteres podem servir de critérios de seleção indireta para aumentar o peso de polpa de goiabeira-serrana, pois são de fácil mensuração.(AU)


Assuntos
Feijoa/anatomia & histologia , Feijoa/crescimento & desenvolvimento , Pesos e Medidas , Frutas/anatomia & histologia , Seleção Genética
6.
Sci. agric ; 72(1): 62-68, Jan.-Feb. 2015. ta, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497466

Resumo

Woolly apple aphid (WAA; Eriosoma lanigerum Hausm.) is a major insect pest that has significant economic impact on apple growers worldwide. Modern breeding technologies rely on several molecular tools to help breeders select genetic determinants for traits of interest. Consequently, there is a need for specific markers linked to the genes of interest. Apple scions and rootstocks have an additional barrier to the introduction of pest resistance genes due to the presence of self-incompatibility S-RNase alleles. The genetic characterization and early identification of these alleles can amplify the contribution of a breeding program to the selection of resistant genitors that are as compatible as possible. In this study, we identified the Er1 gene involved in the resistance to WAA in Malus prunifolia var. ringo, also known as Maruba Kaido rootstock, and we analyzed the inheritance pattern of the WAA resistance Er1 gene in a segregant population derived from Malus pumila M.9 and Maruba Kaido rootstocks. The self-incompatibility of S-RNase alleles S6S26 of Maruba Kaido were also identified along with their inheritance pattern. We also confirmed the identification of the S1S3 alleles in the M.9 rootstock. To the best of our knowledge, this is the first study to characterize WAA resistance and RNase S-alleles in Maruba Kaido. Furthermore, we discuss the potential use of the genetic markers for these genes and their potential impact on apple breeding programs.


Assuntos
Malus/genética , Melhoramento Vegetal , Pragas da Agricultura
7.
Sci. agric. ; 72(1): 62-68, Jan.-Feb. 2015. ta, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-30060

Resumo

Woolly apple aphid (WAA; Eriosoma lanigerum Hausm.) is a major insect pest that has significant economic impact on apple growers worldwide. Modern breeding technologies rely on several molecular tools to help breeders select genetic determinants for traits of interest. Consequently, there is a need for specific markers linked to the genes of interest. Apple scions and rootstocks have an additional barrier to the introduction of pest resistance genes due to the presence of self-incompatibility S-RNase alleles. The genetic characterization and early identification of these alleles can amplify the contribution of a breeding program to the selection of resistant genitors that are as compatible as possible. In this study, we identified the Er1 gene involved in the resistance to WAA in Malus prunifolia var. ringo, also known as Maruba Kaido rootstock, and we analyzed the inheritance pattern of the WAA resistance Er1 gene in a segregant population derived from Malus pumila M.9 and Maruba Kaido rootstocks. The self-incompatibility of S-RNase alleles S6S26 of Maruba Kaido were also identified along with their inheritance pattern. We also confirmed the identification of the S1S3 alleles in the M.9 rootstock. To the best of our knowledge, this is the first study to characterize WAA resistance and RNase S-alleles in Maruba Kaido. Furthermore, we discuss the potential use of the genetic markers for these genes and their potential impact on apple breeding programs.(AU)


Assuntos
Melhoramento Vegetal , Pragas da Agricultura , Malus/genética
8.
Rev. Ciênc. Agrovet. (Online) ; 13(3): 238-246, 2014. tab, graf
Artigo em Português | VETINDEX | ID: biblio-1488058

Resumo

The aim of this study was to assess the effect of the processing phases on the physical and physiological quality of seeds of two Creole genotypes and two varieties of open pollinated corn, as well as test the processing efficiency of the system. The seeds were collected at the reception, after pre-cleaning, the drying process, size and density classification, and storage. The seeds were evaluated for the moisture content, physical purity, germination, germination index, accelerated aging, cold test, tetrazolium, electrical conductivity, and seedling and radicle length. The processing enhanced the seed quality, and higher performance was observed for the analyzed parameters during storage. The Creole genotypes were more tolerant to processing and showed higher physical and physiological seed quality.


O objetivo do presente trabalho foi verificar o efeito das fases do beneficiamento sobre a qualidade física e fisiológicas de sementes de dois genótipos crioulos e duas variedades de polinização aberta de milho, bem como testar a eficiência do sistema de beneficiamento. As sementes foram amostradas na recepção na unidade de beneficiamento; após a pré-limpeza; após a secagem; após a passagem pela classificação por tamanho e densidade; e no armazenamento. As sementes foram avaliadas quanto ao teor de água, pureza física, germinação, índice de velocidade de germinação, envelhecimento acelerado, teste de frio, tetrazólio, condutividade elétrica, comprimento de plântula e radícula. O beneficiamento realçou a qualidade das sementes, sendo que aquelas no pré-ensaque apresentaram-se com desempenho superior quanto aos parâmetros analisados. Os genótipos crioulos foram mais tolerantes ao benefi ciamento que as variedades de polinização aberta, pois a qualidade física e fisiológica foi preservada até o armazenamento.


Assuntos
Sementes/anatomia & histologia , Sementes/fisiologia , Zea mays/embriologia , Sais de Tetrazólio
9.
R. Ci. agrovet. ; 13(3): 238-246, 2014. tab, graf
Artigo em Português | VETINDEX | ID: vti-28055

Resumo

The aim of this study was to assess the effect of the processing phases on the physical and physiological quality of seeds of two Creole genotypes and two varieties of open pollinated corn, as well as test the processing efficiency of the system. The seeds were collected at the reception, after pre-cleaning, the drying process, size and density classification, and storage. The seeds were evaluated for the moisture content, physical purity, germination, germination index, accelerated aging, cold test, tetrazolium, electrical conductivity, and seedling and radicle length. The processing enhanced the seed quality, and higher performance was observed for the analyzed parameters during storage. The Creole genotypes were more tolerant to processing and showed higher physical and physiological seed quality.(AU)


O objetivo do presente trabalho foi verificar o efeito das fases do beneficiamento sobre a qualidade física e fisiológicas de sementes de dois genótipos crioulos e duas variedades de polinização aberta de milho, bem como testar a eficiência do sistema de beneficiamento. As sementes foram amostradas na recepção na unidade de beneficiamento; após a pré-limpeza; após a secagem; após a passagem pela classificação por tamanho e densidade; e no armazenamento. As sementes foram avaliadas quanto ao teor de água, pureza física, germinação, índice de velocidade de germinação, envelhecimento acelerado, teste de frio, tetrazólio, condutividade elétrica, comprimento de plântula e radícula. O beneficiamento realçou a qualidade das sementes, sendo que aquelas no pré-ensaque apresentaram-se com desempenho superior quanto aos parâmetros analisados. Os genótipos crioulos foram mais tolerantes ao benefi ciamento que as variedades de polinização aberta, pois a qualidade física e fisiológica foi preservada até o armazenamento.(AU)


Assuntos
Zea mays/embriologia , Sementes/anatomia & histologia , Sementes/fisiologia , Sais de Tetrazólio
10.
Sci. agric ; 71(2): 120-125, Mar-Abr. 2014. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497400

Resumo

Plant breeding efficiency relies mainly on genetic diversity and selection to release new cultivars. This study aimed to identify landraces with favorable characteristics that can be used as parents of segregating populations in common bean (Phaseolus vulgaris L.) breeding programs. Firstly, ten bean genotypes were selected because they showed promising agronomic performance, and the following seven adaptive traits of four commercial bean cultivars were evaluated: i) plant height; ii) diameter of the stem; iii) height of the insertion of the first pod; iv) pod number per plant; v) grain number per pod; vi) weight of a thousand grains and vii) grain yield. The accessions BAF 07, BAF 44, and BAF 45 are promising in terms of increasing plant height, and accession BAF 01, in terms of reducing plant height. The accession BAF 07 was also the most promising in terms of a plant ideotype that combines higher plant height, maximum height of the insertion of the first pod, and increment in grain yield. Moreover, the selection can be made between and within accessions, because genetic variability is also present within landraces.


Assuntos
Bancos de Espécimes Biológicos , Melhoramento Vegetal , Phaseolus/genética , Seleção Genética , Variação Genética
11.
Sci. Agric. ; 71(2): 120-125, Mar-Abr. 2014. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-28435

Resumo

Plant breeding efficiency relies mainly on genetic diversity and selection to release new cultivars. This study aimed to identify landraces with favorable characteristics that can be used as parents of segregating populations in common bean (Phaseolus vulgaris L.) breeding programs. Firstly, ten bean genotypes were selected because they showed promising agronomic performance, and the following seven adaptive traits of four commercial bean cultivars were evaluated: i) plant height; ii) diameter of the stem; iii) height of the insertion of the first pod; iv) pod number per plant; v) grain number per pod; vi) weight of a thousand grains and vii) grain yield. The accessions BAF 07, BAF 44, and BAF 45 are promising in terms of increasing plant height, and accession BAF 01, in terms of reducing plant height. The accession BAF 07 was also the most promising in terms of a plant ideotype that combines higher plant height, maximum height of the insertion of the first pod, and increment in grain yield. Moreover, the selection can be made between and within accessions, because genetic variability is also present within landraces.(AU)


Assuntos
Phaseolus/genética , Bancos de Espécimes Biológicos , Melhoramento Vegetal , Variação Genética , Seleção Genética
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