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Viabilidade de aplicação da seleção precoce em batata-doce [Ipomoea batatas (L.) Lam.] e avaliação de caracteres relacionados à produção / Viability of application of early selection in sweet potato [Ipomoea batatas (L.) Lam.] and evaluation of traits related to productionMoreira, Glaucia Bethânia Rocha 23 August 2016 (has links)
A cultura da batata-doce assume papel importante no cenário agrícola nacional por ser considerada uma espécie altamente versátil, que consegue suprir as necessidades nutricionais da população, além de atualmente ser foco da cadeia de produção do etanol, pelo seu elevado teor de amido. Apesar da importância dessa cultura, ela é pouco estudada e, no que se refere ao melhoramento genético dessa espécie, os estudos são ainda mais escassos. Essa falta de informações acerca dos genótipos mais adaptados às condições de determinada região é um dos principais problemas enfrentados pelos produtores de batata-doce que não conseguem atingir o máximo de produtividade, pois as variedades utilizadas não conseguem expressar o seu potencial. Visando a aceleração dos programas de melhoramento, surge como alternativa a realização da seleção precoce, podendo-se realizar o descarte de materiais com características desfavoráveis nas primeiras gerações clonais. Para auxiliar na seleção precoce, a utilização de técnicas multivariadas como a análise GGE Biplot é de fundamental importância para se atingir sucesso na seleção. Dessa forma, os objetivos do presente trabalho foram (a) avaliar a eficiência da seleção precoce em batata-doce, bem como identificar possíveis correlações entre características morfológicas, para auxiliar na seleção de genótipos superiores; (b) identificar genótipos produtivos e que apresentem características de raiz favoráveis para o mercado e com elevado teor de amido para serem utilizados em futuros programas de melhoramento. Os experimentos foram realizados em casa de vegetação, onde foram avaliados em três épocas distintas, além de uma vez a campo para a mensuração dos caracteres relacionados à produção e ao teor de amido. Pelos resultados observados, nota-se que a utilização da técnica de seleção precoce em batata-doce pode não ser eficiente pelo comportamento que os genótipos assumiram no decorrer das avaliações, já que a correlação entre épocas foi muito baixa ou até mesmo inexistente, o que dificulta a seleção em etapas iniciais do programa. Porém, com relação às correlações entre as características em uma mesma época, nota-se que várias delas apresentaram correlações positivas, levando à interpretação de que se selecionarmos para uma determinada característica, automaticamente selecionaremos para outra correlacionada a esta. Os resultados para os caracteres produtivos indicam que existem genótipos que apresentam elevado potencial produtivo, superior à média nacional e também apresentam características desejáveis na forma e tamanho das raízes tuberosas. Além dessas características, algumas contêm elevado teor de amido, o que é altamente desejável para a indústria de biocombustíveis. Pode-se concluir que a técnica de seleção precoce não é recomendável para a cultura, mas existem características altamente correlacionadas em uma época específica. Existem genótipos que podem ser utilizados em programas de melhoramento, tanto pelo seu elevado potencial produtivo e características de raiz desejáveis quanto pela concentração de amido. / The culture of sweet potato plays an important role in the national agricultural scenario because it is considered a highly versatile species that can meet the nutritional needs of the population, in addition to currently being the focus of the ethanol supply chain, for their high starch content. Despite the importance of this crop, it is little studied and, in relation to the genetic improvement of this species, studies are still more scarce. This lack of information about the genotypes most adapted to the conditions of a given region is one of the main problems faced by sweet potato producers who fail to achieve maximum productivity, as the varieties used can not express their potential. Aiming at the acceleration of plant breeding programs, the alternative of performing early selection arises, and the disposal of materials with unfavorable characteristics can be carried out in the first clonal generations. And to assist in the early selection, using multivariate techniques such as GGE Biplot analysis is crucial to achieving success. Thus, the objectives of this study were (a) to evaluate the efficiency of early selection in sweet potatoes, as well as to identify possible correlations between morphological characteristics, in order to assist in the selection of superior genotypes; (b) to identifying productive genotypes that exhibit favorable root characteristics for the market and with high starch content for use in future breeding programs. The experiments were conducted both in greenhouse and in field conditions, where the traits related to production and starch content were assessed at three different times and one time, respectively. The results indicate that the use of the early selection technique in sweet potatoes may not be efficient, on the basis of the behavior shown by the genotypes in the assessments, since the correlation between assessment times was very low or even non-existent, making it difficult for selection to be applied in the initial stages of the program. However, regarding the correlations between the characteristics in the same assessment instance, it can be noted that several of them had positive correlations, implying that, if a particular feature is selected for, that automatically selects for others correlated to this. The results for the productive characters indicate that there are genotypes that have high yield potential, higher than the national average and that also have desirable characteristics regarding the shape and size of the tuberous roots. In addition to these features, some accessions have high starch content, which is highly desirable for the biofuel industry. It can be concluded that the early selection technique is not recommended for this crop, but there are nonetheless highly correlated characters at particular times. There are genotypes that can be utilized in breeding programs, both for their high yield potential associated to desirable root characteristics and for the concentration of starch.
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Estratificação ambiental para avaliação de genótipos de algodoeiro no estado de Mato Grosso. / Environmental stratification for evaluation cotton genotypes in Mato Grosso State, Brazil.Maranha, Fábia Giulianna Christian Botelho 19 May 2005 (has links)
Utilizando dados de produtividade dos experimentos regionais de avaliação de genótipos de algodoeiro (Gossypium hirsutum) conduzidos no estado de Mato Grosso, nos anos agrícolas 1998/99, 1999/00 e 2000/01, foi realizado este trabalho, com a finalidade de estratificar e determinar o número de ambientes para avaliação de genótipos de algodão. Para isso foram avaliados oito genótipos em 1998/99, 14 em 1999/00 e 15 em 2000/01 em oito ambientes, quais sejam: Campo Novo dos Parecis, Sorriso, Primavera do Leste, Rondonópolis, Campo Verde, Sapezal, Pedra Preta e Lucas do Rio Verde. A partir das análises de variância foram aplicadas técnicas fundamentadas na análise AMMI (Additive Main effects and Multiplicative interactions). A primeira estratificação baseou-se na distância entre locais para a interação por um modelo AMMI de análise. O segundo método baseou-se na abordagem de genótipos vencedores, utilizando-se as estimativas dos modelos AMMI1 e AMMI2. As duas metodologias aplicadas permitiram a formação de estratos ambientais para todos os anos de avaliação. As matrizes de coincidências para os três anos de avaliação permitiram inferir que os estratos formados têm caráter preditivo, pois foram identificados a partir de conjuntos de genótipos diferentes em cada ano e se confirmaram nos três anos de estudo. Assim, por meio da metodologia baseada na distância para interação observou-se a formação de um estrato compreendendo Campo Verde e Lucas do Rio Verde. Entretanto a metodologia baseada em genótipos vencedores permitiu a formação de dois estratos envolvendo quatro dos oito locais avaliados, sendo o primeiro grupo constituído por Sorriso e Lucas do Rio Verde e segundo composto por Primavera do Leste e Lucas do Rio Verde. A metodologia baseada em genótipos vencedores possibilitou a formação de estratos ambientais baseados em critérios estatísticos de fácil entendimento e apresentação gráfica clara, permitindo a delimitação de estratos de forma matemática, baseada na performance dos genótipos vencedores. Ela informou de maneira integrada a recomendação de genótipos de adaptação específica para cada estrato de ambientes. / Data of yield were obtained from Regional Yield Trials of cotton (Gossypium hirsutum) genotypes carried out in Mato Grosso State, Brazil in 1998/99, 1999/00 and 2000/01, was used in this study on environmental stratification and evaluation of the minimum number of environments required for cotton genotypes assessments. Eight genotypes were evaluated in 1998/99, fourteen in 1999/00 and fifteen in 2000/01. The genotypes were planted in the following eight locations: Campo Novo dos Parecis, Sorriso, Primavera do Leste, Rondonópolis, Campo Verde, Sapezal, Pedra Preta e Lucas do Rio Verde. From the analysis of variance and the environmental means, two techniques were applied based on AMMI analysis (Additive Main effects and Multiplicative Interactions) analysis. The first method was based on an interaction distance between locations estimated by AMMI analysis. The second method was based on the winning genotypes approach, throught the interactions estimates from models AMMI1 and AMMI2. The methodologies were efficient to provide an environmental stratification at every years of evaluation. The results of the matrix of coincidences over the three years of this study suggested the formed strata have a predictive property, since their identification was based on a different set of genotypes in each year and they remained the same over the years. Then, the method based on an interaction distance between locations estimated by AMMI analysis permited to constitute one stratum involving Campo Verde and Lucas do Rio Verde. However, the method based on the winning genotypes approach has formed a two strata involving four locations; the first group was constitute by Sorriso and Lucas do Rio Verde and the second involved the locations Primavera do Leste and Lucas do Rio Verde. The methodology based on the winning genotypes approach to made possible the formation of environmental strata based on statistical criteria of easy understanding and showing graphic display. This method to allowed the demarcation of strata in a mathematical way through the performance winning genotypes; it provided an integrated understanding about the recommendation of genotypes with specific adaptation for each environmental stratum.
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O Sistema de Unidades Demonstrativas de Feijão - SUDF - como alternativa para o desenvolvimento da produção de feijão no Rio Grande do Sul / The Common Bean Demonstration Unity System – SUDF – as an alternative for common bean production development in Rio Grande do Sul State, Brazil.Villela, Alexandre Terracciano 25 August 2016 (has links)
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Previous issue date: 2016-08-25 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Alimento de grande importância na dieta da população brasileira, o feijão
(Phaseolus vulgaris L.) é cultivado preferencialmente por agricultores familiares
no Rio Grande do Sul. Diversos são os motivos que levam os produtores em
grande escala a terem um maior acesso às tecnologias geradas pela pesquisa,
tanto de órgãos públicos como privados, em relação aos agricultores familiares.
Assim, no início dos anos 1990, a equipe de melhoramento genético da Embrapa
Clima Temperado, com a contribuição da Emater/RS, órgão oficial de extensão,
colocaram em prática o Sistema de Unidades Demonstrativas de Feijão – SUDF –
possibilitando aos agricultores familiares conhecerem as cultivares
disponibilizadas pela pesquisa e, consequentemente, escolherem as melhor
adaptadas às condições ambientais de suas propriedades. A Unidade
Demonstrativa - UD – passou a ser composta por dezessete das cultivares já
recomendadas por órgãos de pesquisa localizados na Região Sul do Brasil, além
da cultivar em uso pelo agricultor, usada como termo de comparação. As parcelas
constituíram-se de quatro fileiras de 4 m, com 0,50 m entre fileiras e com uma
densidade de 12 sementes por metro linear. O SUDF foi concebido para ser uma
metodologia dinâmica, de modo a permitir o acréscimo ou a eliminação anual de
cultivares. Assim, sempre que uma nova cultivar tornava-se disponível pela
pesquisa, poderia ser acrescida. Da mesma forma, cultivares poderiam ser
eliminadas quando algum fator considerado como determinante assim o
sugerisse. UDs foram instaladas em todas as doze regiões administrativas da
Emater-RS. O presente trabalho analisa o comportamento em cada uma das
regiões, de dezessete das cultivares oriundas da pesquisa e que compuseram o
SUDF, mais a cultivar usada pelo agricultor, que igualmente serviu como
testemunha, totalizando dezoito cultivares. As cultivares oriundas da pesquisa
foram: Rio Tibagi, Guateian 6662, FT 120, BR-Ipagro 1 Macanudo, BR-Ipagro 3
Minuano, Iapar 44, BR-Ipagro 35 Macotaço, BR-Fepagro 44 Guapo Brilhante, TPS
Nobre (também identificada como FT Nobre), Diamante Negro, BRS Valente,
Soberano e BRS Expedito, cultivares de grãos pretos; e Carioca, Iraí, Iapar 31 e
Pérola, cultivares com outras cores de tegumento. Os resultados apontam que
embora em cada uma das regiões grupos distintos de cultivares tenham revelado
maiores produtividades, nove delas, as cultivares BR-Ipagro 35 Macotaço, BRS
Expedito, BR-Ipagro 3 Minuano, BR-Ipagro 1 Macanudo, Soberano e FT Nobre,
de grãos pretos, e Carioca e Iapar 31, de grãos cariocas, estiveram, maciçamente
no grupo de produtividade superior. A comparação entre as cultivares integrantes
do SUDF e a cultivar do agricultor, revelou que em seis das doze regiões
administrativas da Emater – RS, pelo menos uma das cultivares do SUDF
superou a produtividade desta última, abrindo a perspectiva de um avanço na
média de produtividade do feijão no Estado. / ood source of great importance in the Brazilian population diet, the common
bean (Phaseolus vulgaris L.) is grown preferably by family farmers in Rio Grande
do Sul State. There are several reasons that lead to large-scale producers to have
greater facility in accessing technologies released by research institutions, both
public and private, in relation to family farmers. As so, in beginning 1990s, the
common bean breeding team of Embrapa Temperate Climate, with the
contribution of Emater / RS, the official extension institution, put into practice the
Common Bean Demonstration Unity System - SUDF - enabling farmers to get
acquainted with the new released cultivars by research, with the possibility of
selection of those best suited to the environment of their farms.The Demonstration
Unity – DU, was composeed by seventeen of the cultivars released for cultivation
by research institutions located at Brazil’s Southern Region, as well as by the
farmer’s cultivar, also the check cultivar. The plots consisted of four 4m-rows, with
0.50m between rows and a density of 12 seeds per meter. The SUDF was
designed to be a dynamic methodology as to allow for the addition or elimination
of cultivars annually according to the needs. DUs have been sown at all of the
Emater- RS’s Administration Regions. So, the present work analyses seventeen of
the cultivars derived from the research, plus one cultivar under use by the farmer,
totaling eighteen cultivars. The cultivars available for research were: Rio Tibagi,
Guateian 6662, FT 120, BR-Ipagro 1 Macanudo, BR-Ipagro 3 Minuano, Iapar 44,
BR-Ipagro 35 Macotaço, BR-Fepagro 44 Guapo Brilhante, TPS Nobre (or FT
Nobre), Diamante Negro, BRS Valente, Soberano and BRS Expedito, black
seeded cultivars; and Carioca, Iraí, Iapar 31 and Pérola cultivars with differente
seed coat colors. Results reveal that despite the fact that at each of the
Administrative Regions distinct groups of cultivars were the most yielding ones,
the cultivars BR-Ipagro 35 Macotaço, BRS Expedito, BR-Ipagro 3 Minuano, BRIPAGRO
1 Macanudo, Soberano e FT Nobre, black seeded, and Carioca and
Iapar 31, of carioca type, have been mainly at the high yield group. Comparison
between the farmer’s cultivar and the SUDF cultivars shows that at six of the
twelve regions, at least one of SUDF cultivars outyield the farmer’s cultivar,
opening the perspective of a common bean mean yield gain for Rio Grande do
Sul.
Key words: Ph
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Divergência genética e capacidade de combinação em linhagens de pimentão (Capsicum annuum L.)MENDES, Adônis Queiroz 31 July 2009 (has links)
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Previous issue date: 2009-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the genus Capsicum are inserted 32 species,predominantly originate from tropical and subtropical regions of America. Among the species of the genus is included Capsicum annuum L. containing the sweet peppers and some peppers. This study aimed to determine the genetic divergence using molecular marker of type ISSR and evaluate the ability general capacity (CGC) and specific capacity (CEC) of combination of linkages of sweet pepper. The experiment was conducted at the Department of Agronomy, Federal Rural University of Pernambuco (UFRPE), in Recife-PE, with latitude of 8 10'52''S and longitude 34 54'47''W between 20 July 2008 and 05 April 2009. Linkages were used HTV-1, HTV-8, HTV-9, HTV-10, HTV-11 and HTV-12, provided by the company Hortivale – Sementes do Vale LTDA, sown and whiting of around 20 days of sowing samples were collected for the first leaves to extract genomic DNA and the reactions of amplification with 21 primer’s of ISSR selected from a set produced by the University of Bristish Columbia, Vancouver, Canadá. After 30 days the seedlings were transplanted to pots with a capacity of five liters using coconut fiber as a substrate, fertirrigated daily with nutrient solution in greenhouse. During the flowering crosses were made in the morning is obeying the partial diallel among the six linkages resulted in fifteen experimental hybrids, where their fruits were harvested and seeds extracted manually. The six parents and the fifteen hybrids were evaluated in the greenhouse system similar to obtain the hybrids, using the experimental design of randomized blocks with four replications, where each experimental plot was composed of four pots with one plant each. The spacing between lines was 1.00 m and between plants in the same line of 0.5 m. The plants were conducted with only four stems and removed the lateral shoots up to the first fork and the flower thereof. The characteristics were observed and evaluated the following: total weight of fruit (PTF); total number of fruits (NTF), average weight of fruit (PMF); average fruit length (CMF); average fruit diameter (DMF); length/diameter ratio (RCD); average number of locules (NL); and average thickness of the pericarp (EP). Analysis of the ISSR the amplification of DNA fragments were 145, with an average of 6.9 per oligonucleotide fragments ranging from 300 to 1500 bp. Through the molecular data generated a dendrogram was, considering the average dissimilarity of 13.51%, which was the formation of three distinct groups. In the first group observed HTV-10, HTV-8, HTV-12 and HTV-11, already the second and third groups were formed by a genotype in each and they HTV-1 and HTV-9 respectively. The HTV-9 genotype was isolated from the others, presenting a dissimilarity of 20.31% with HTV-11, the most found among all genotypes. The small dissimilarity was found between HTV-8 and HTV-12 (4.92%) these materials are the most similar comparedwith other genotypes. In the study combining ability of the heritability obtained values between 48.4% and 91.4% for the features except the average number of locules has not submitted genetic variability. The ratios between CGC and CEC indicating that the actions of gene linkages studied favor the expression of additive genetic effects. With respect to the CGC, the linkage HTV-8 showed negative values for all characteristics evaluated, the linkages HTV-9 and HTV-10 showed highly positive for PTF. With respect to estimates of CEC, they were negative in all lines on the characteristics PTF, PMF, CMF and DMF. The hybrid HTV-8 x HTV-10 that stood out with higher PTF and PMF making promising potential as a hybrid business has, in addition to high CEC value for at least one of the parents with high value of GCC. The results obtained with molecular data showed some inconsistencies when compared to combinatorial analysis showing low accuracy, these materials, in the indication of possible superior hybrid combinations. / No gênero Capsicum estão inseridas 32 espécies, predominantemente são originárias das regiões tropicais e subtropicais da América. Dentre as espécies do referido gênero está Capsicum annuum L. que contêm os pimentões e algumas pimentas. Este trabalho teve como objetivo determinar a divergência genética utilizando marcador molecular do tipo ISSR e avaliar a capacidade geral e específica de combinação entre linhagens de pimentão. O experimento foi realizado no Departamento de Agronomia, Área de Fitotecnia, da Universidade Federal Rural de Pernambuco (UFRPE), em Recife-PE, com latitude de 8º10’52’’S e longitude de 34º54’47’’W entre 20 de Julho de 2008 e 05 de Abril de 2009. Foram utilizadas as linhagens HTV- 1, HTV-8, HTV-9, HTV-10, HTV-11 e HTV-12, cedidas pela empresa Hortivale – Sementes do Vale LTDA, semeadas em badejas de isopor e por volta dos 20 dias após o semeio se coletou amostras das primeiras folhas definitivas para extração do DNA genômico e as reações de amplificação utilizando 21 oligonucleotídeos de ISSR selecionados de um conjunto produzido pela University of Bristish Columbia, Vancouver, Canadá. Após 30 dias do semeio as mudas foram transplantadas para vasos com capacidade de cinco litros utilizando como substrato o pó de coco, fertirrigadas diariamente com solução nutritiva e mantidas em casa de vegetação. Durante o florescimento se realizou polinizações manuais no início da manhã obedecendo-se o esquema dialélico parcial entre as seis linhagens resultando em quinze híbridos experimentais, onde seus frutos foram colhidos e as sementes extraídas manualmente. Os seis genitores e as quinze combinações híbridas foram avaliados em cultivo protegido em sistema semelhante à obtenção dos híbridos, utilizando o delineamento experimental de blocos casualizados com quatro repetições, onde cada parcela experimental foi constituída por quatro vasos com uma planta cada. O espaçamento entre linhas foi de 1,0 m e entre plantas na mesma linha de 0,5 m. As plantas foram conduzidas com apenas quatro hastes e realizou-se a retirada dos brotos laterais até a primeira bifurcação bem como a flor desta. As características observadas e avaliadas foram as seguintes: peso total de frutos (PTF), número total de frutos (NTF), peso médio dos frutos (PMF), comprimento médio do fruto (CMF), diâmetro médio do fruto (DMF), relação comprimento/diâmetro do fruto (RCD), número de lóculos do fruto (NL) e espessura média do pericarpo (EP). Na análise de ISSR as amplificações tiveram 145 fragmentos de DNA, com uma média de 6,9 fragmento por oligonucleotídeo variando de 300 à 1500 pb. Através dos dados moleculares foi gerado um dendrograma, considerando a dissimilaridade média de 13,51%, onde houve a formação de três agrupamentos distintos. No primeiro grupo observamos HTV-10, HTV-8, HTV-12 e HTV-11, já o segundo e terceiro grupos foram formados por um genótipo em cadasendo eles HTV-1 e HTV-9 respectivamente. O genótipo HTV-9 foi isolado dos demais, apresentando uma dissimilaridade de 20,31% com o HTV-11, a maior encontrada entre todo os genótipos. A menor dissimilaridade foi verificada entre HTV-8 e HTV-12 (4,92%), sendo esses materiais mais próximos em relação aos outros genótipos. No estudo da capacidade combinatória a herdabilidade obteve valores entre 48,4% e 91,4% para a maioria das características com exceção do número de lóculos que não apresentou variabilidade genética. As razões entre os quadrados médios CGC com CEC mostraram valores superiores a 1,0 indicando que as ações gênicas das linhagens estudadas favorecem a manifestação de efeitos gênicos aditivos das características estudadas. Com relação apenas a CGC a linhagem HTV-8 apresentou valores negativos para todas as características avaliadas, já as linhagens HTV-9 e HTV-10 mostraram valores altamente positivos para PTF. Com relação as estimativas de CEC, estas foram negativas em todas as linhagens para as características PTF, PMF, CMF e DMF. O híbrido HTV-8 x HTV-10 se destacou para os caracteres PTF e PMF apresentando maior potencial tornando-o promissor como um híbrido comercial, que possui, além de alto valor para CEC, um dos genitores com alto valor positivo de CGC. As dissimilaridades obtidas com os dados moleculares apresentaram algumas incoerências quando comparados com a análise combinatória apresentando baixa precisão, nesses materiais, na indicação de possíveis combinações híbridas superiores.
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Seleção recorrente em abobrinha 'piramoita' (Cucurbita moschata Duch.) /Cardoso, Antonio Ismael Inácio, 1965- January 2004 (has links)
Memorial apresentado à Faculdade de Ciências Agrônomicas, UNESP, Câmpus de Botucatu, para fins de concurso público para obtenção do título de Livre-Docente na disciplina "Hortaliças de Frutos" junto ao Departamento de Produção Vegetal / Resumo: Seleção recorrente é um dos métodos mais eficientes para o melhoramento de espécies alógamas, especialmente quando progênies S1 são utilizadas. Considerando-se que abobrinha geralmente não apresenta perda de vigor pela endogamia, este método pode ser adequado para o melhoramento desta espécie. Neste trabalho foram realizados experimentos com o objetivo de avaliar a eficiência da seleção recorrente em abobrinha 'Piramoita'. Foram realizados três ciclos de seleção recorrente a partir da cultivar Piramoita (população P0), com avaliação e seleção de progênies S1. Novas populações foram obtidas com a recombinação de plantas das progênies selecionadas, utilizando-se sementes remanescentes. No primeiro ciclo foram avaliadas 74 progênies e selecionadas 14, no segundo foram avaliadas 60 e selecionadas 10 progênies e no terceiro ciclo foram avaliadas 77 e selecionadas 12 progênies. Foram obtidas populações melhoradas após um (PI), dois (PII) e três (PIII) ciclos de seleção recorrente. Quatro populações (P0, PI, PII e PIII) foram avaliadas em um delineamento em blocos ao acaso, com oito repetições e cinco plantas por parcela. Em todos os experimentos foram avaliadas as seguintes características: número de frutos total e comercial por planta, % de frutos comerciais, produção, em massa, de frutos total e comercial por planta e a massa média de fruto comercial. Foram observados aumentos de produção lineares significativos ao longo dos ciclos de seleção. Para número de frutos total e comercial e produção, em massa, total e comercial foram obtidos aumentos com a população PIII, comparativamente a população inicial, de 32, 63, 24 e 57%, respectivamente. A massa média de fruto comercial não foi afetada pela seleção recorrente. Conclui-se que a seleção recorrente foi eficiente para melhorar a abobrinha 'Piramoita'... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Recurrent selection is one of the most efficient methods to improve alogamous crops, especially when S1 progenies are utilized. Since squash usually does not have inbreeding depression, this method may be adequate for squash improvement. In this study, experiments were set up to evaluate recurrent selection efficiency in 'Piramoita' squash. Three cycles were made from cultivar Piramoita (population P0), with evaluation and selection of S1 progenies and recombination of plants from selected progenies, using remained seeds. In the first cycle, 74 progenies were evaluated and 14 were selected, in the second 60 progenies were evaluated and 10 were selected and in the third cycle 77 progenies were evaluated and 12 were selected. Improved populations were obtained after one (PI), two (PII) and three (PIII) cycles of recurrent selection. Four populations (P0, PI, PII and PIII) were evaluated in a randomized block design, with eight replicates and five plants per plot. In all experiments the following characteristics were evaluated: total and commercial number of fruits per plant, total and commercial fruit yield, percentage of commercial fruit and commercial average fruit weight. Linear regressions of yield, number and weight of fruits over selection cycles were obtained. Total and commercial number and weight of fruits per plant were improved from P0 to PIII by 32, 63, 24 and 57%, respectively. Commercial average fruit weight was not affected by selection cycles. It is concluded that recurrent selection was efficient to improve 'Piramoita' squash, regarding to total fruit yield and, mainly, to commercial fruit yield. S1 progenies obtained from improved population were also superior to progenies obtained from the original one.
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Reprodução em Brachiaria spp.: SERK (Somatic Embryogenesis Receptor-Like Kinase) no desenvolvimento da antera, do ovário e na embriogênese / Reproduction in Brachiaria spp.: SERK (SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE) in anther and ovary development and in embryogenesisAndréa Dias Koehler 30 March 2010 (has links)
Gramíneas do gênero Brachiaria apresenta importância econômica como forrageiras no Brasil. O melhoramento genético, entretanto, é restrito devido a diferenças de ploidia entre os genótipos e a reprodução por apomixia. A indução de haplóides e duplo-haploides pelo cultivo in vitro de anteras ou de micrósporos isolados é relatada em diversas espécies. Além da criação de novos genótipos linhagens duplo-haplóides podem ser utilizadas como ferramentas para o estudo de marcadores moleculares. Dentre os fatores essenciais para o sucesso da técnica está o estádio do desenvolvimento do micrósporo, sendo o estádio uninucleado, geralmente, o mais responsivo. Um dos objetivos deste trabalho foi contribuir para a definição de parâmetros para a cultura de haplóides em Brachiaria. Flores e anteras isoladas de B. brizantha (B105) em diferentes estádios de desenvolvimento foram processadas para microscopia de luz. Os eventos observados foram associados a marcadores morfologicos. Experimentos de cultura de anteras foram estabelecidos e estruturas semelhantes a calos ocorreram em pouco explantes. Secções histológicas revelaram a ocorrência de micrósporos com divisão simétrica, indicando um possível desvio da rota do micrósporo para a rota esporofítica. Genes definidos como marcadores de embriogênese como SERK (SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE), podem ser utilizados para identificar o potencial embriogênico de células ou grupo de células, possibilitando monitorar a resposta in vitro. Duas seqüências parciais de cDNA isoladas de B. brizantha apresentaram alta identidade com homólogos de SERK1 e SERK2 de monocotiledôneas. Análise filogenética confirmou a alta similaridade sugerindo serem os possíveis ortólogos de SERK em Brachiaria, sendo nomeados como BbrizSERK1 e BbrizSERK2. Clones parciais da seqüência genômica foram obtidos. Análise de Southern blot identificou duas cópias deste gene tanto na planta apomítica como na sexual. A análise da expressão de BbrizSERK2 por RT-qPCR na planta apomítica e sexual e durante a embriogênese somática revelou que este gene não é específico de tecidos reprodutivos. Expressão diferencial de BbrizSERK entre ovários apomíticos e sexuais, especialmente durante a megasporogênese, foi observada por hibridização in situ. Detectou-se forte sinal na célula-mãe do megásporo em ovários sexuais e ausência de sinal em ovários apomíticos. Após a antese, a expressão na planta apomítica foi observada apenas na região micropilar e proembriões. Na sexual, foi observada nas antípodas e aparato da oosfera. Em anteras o mesmo padrão de expressão foi observado entre a planta apomítica e sexual, com forte expressão no tapete e nas células-mãe do grão de pólen, o que sugere um importante papel deste gene na esporogênese em Brachiaria. Em calos embriogênicos forte sinal foi observado em massas proembriogênicas, em embriões globulares e também em embriões somáticos mais desenvolvidos, confirmando a função de SERK como marcador de embriogênese em Brachiaria. Em anteras cultivadas in vitro, forte sinal foi observado em micrósporos binucleados com divisão simétrica e em alguns micrósporos vacuolados. Experimentos futuros com genes desta família poderão contribuir para monitorar processos in vitro em Brachiaria, indicando células ou grupos de células com potencial embriogênico, ajudando na definição das melhores condições de cultivo para a embriogênese e também para o estudo da reprodução neste gênero / Brachiaria, gramineae present economic importance as forage in Brazil. The genetic breeding, however, is restricted by differences in ploidy among the genotypes and the apomixis. The development of a haploid and double haploid production has been reported for several species. Besides the production of new genotypes the development of double haploid lineages may be used for studies with molecular markers. Among important factors for the success of haploid plant development relies on the microspore developmental stage, with the uninucleate stage being usually the most responsive. One of the objectives of this work was to contribute for the definition of parameters for the development of haploid cultures in Brachiaria. B. brizantha (B105) flowers and isolated anthers were collected in different stages of development and processed for light microscopy. The events observed were associated to morphological markers. Anther culture experiments were established and calli formation ocurred to a few explants. Histological sections of anthers cultivated in vitro, however, revealled the occurrence of microspores with symmetrical divisions, indicating a possible alternative to the sporophytic route. Genes defined as markers of embryogenesis, such as SERK (SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE), may be utilized to identify the embryogenic potential of cells, or cell clusters, in an attempt to monitor the in vitro response. Two partial sequences of cDna isolated from B. brizantha (B30) showed high identity of these two sequences to SERK1 and SERK2 homologs from monocots. The phylogenetic analysis confirmed high similarity with these genes, indicating that these sequences are possible orthologs of SERK in Brachiaria, hence these were named BbrizSERK1 and BbrizSERK2. Partial clones of genomic sequences were obtained. Southern blot analysis suggested two copies of this gene in both apomictic and sexual B. brizantha. The expression analysis of BbrizSERK2 by RT-qPCR revealed that this gene is not specific to reproductive tissues. Differential expression of BbrizSERK between apomictic and sexual ovaries, especially during megasporogenesis, was observed by in situ hybridization. A strong signal was detected in the megaspore mother cell in sexual ovaries, with absence in apomictic ovaries. After anthesis, the expression in the apomictic plant was observed only in the micropylar region and proembryos, however, in the sexual plant, the expression was observed in the antipodals and egg apparatus. In anthers, the same in situ pattern was observed in the apomictic and the sexual plant, with a strong expression in the tapetum and the pollen grain mother cell, suggesting an important role of this gene in the sporogenesis in Brachiaria. In embryogenic calli, strong signal was observed in proembryogenic masses, globular embryos and somatic embryos in later stages of development, confirming the role of SERK as an embryogenic marker in Brachiaria. In cultivated anthers, a strong signal was observed in binuclear microspores with symmetric division and vacuolated microspores. Further studies with this gene family may contribute to monitoring the in vitro processes in vitro in Brachiaria, defining cells or cell clusters with an embryogenic potential, helping for the definition of culture conditions for embryogenesis and also for reproductive studies in this genus
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Estima??o de par?metros gen?ticos e de diversidade em pinh?o-manso (Jatropha Curcas L.) quanto ? arquitetura de plantas com vari?veis obtidas via an?lise de imagens digitais / Estimation of genetic parameters and diversity in Jatropha curcas L. as the plant architecture with values obtained by digital image analysisMesquita, Daniel Zimmermann 09 July 2015 (has links)
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Previous issue date: 2015-07-09 / The search for renewable energy sources such as biodiesel and ethanol, is a growing trend in
Brazil and in the world due to lower environmental impacts. Among the plant species
available to search, highlight the physic nut (Jatropha curcas L.), that it is a perennial species,
deciduous and with great potential for biodiesel production due to their production
characteristics and quality of oil . However, to date there is no available cultivars for planting,
so the need for basic and applied research. Therefore, it is important to know the behavior of
genotypes and several variables estimated in the culture, among these quotes to the related
plant architecture. The objective of this study was a detailed study of the characteristics
related to plant architecture, in order to know the diversity within and among 10 families of
jatropha half brothers belonging to the Germplasm Collection UFRRJ through digital analysis
images. The treatments (families) were arranged in a randomized design, with 15 replications
(plants). Made to capture images, in the same measuring scale at the time the plants were in
his deciduous period and subsequently through ImageJ software, the images were processed.
It estimated the following variables related to plant architecture: plant height (ALT), stem
diameter (DBC), crown diameter (DCO), number of branches to 50 cm (NR50), opening
angle Canopy (AAB), the total number of forks in the plant (NBI), the average height of the
forks (MAB), number of branches above (NRAcmab) and below (NRAbmab) of MAB, the
sum length of the branches (SCR), area of the plant (APL). It was estimated also in the field,
the number of fruits (NFR) and seeds (NSE), average seed weight (PMS) and grain yield per
plant (PGP), and these were used only in correlation analysis with variables related to plant
architecture. From these data were carried out analysis of variance, correlation, estimation of
genetic parameters and analysis of diversity. Only the variable number of branches to 50 cm
(NR50) was not statistically different between the evaluated progenies. ALT variables, DCO,
NBI, NRAcmab, NRAbmab, SCR and APL had greater genetic influence at the expense of
environmental, justifying the selection of these characteristics. The grain yield per plant
(PGP) had low correlation with all variables, with SCR and NRAcmab showed the highest
values respectively 0.24 and 0.20. The genetic diversity was estimated between families
median ranging between 0.4 and 0.6. The diversity within families was medium to low with
estimates families with more than 0.6 and less than 0.4, respectively, to the families 858, 355
and 869, and 346, 383 and 872. The number of bifurcations (NBI ), the flat area of the plant
(APL) and the sum of the length of the branches (SCR) were the most important features in
the estimation of diversity in this study, with the contribution of respectively 30.55%, 22.29%
and 10, 65%. The family 872 showed favorable aspects related to plant architecture, such as
the high average number of bifurcations (NBI) and, in general, the greatest genetic distance
between the other families. Therefore, prior assessment for evidence of productive potential,
family genotypes 872 may be involved in crosses when you want to explore heterosis culture. / A pesquisa por fontes renov?veis de energia, como o biodiesel e o etanol, ? uma tend?ncia
crescente no Brasil e no mundo devido aos menores impactos ambientais causados. Dentre as
esp?cies vegetais dispon?veis para pesquisa, destaca-se o pinh?o-manso (Jatropha curcas L.),
que se trata de uma esp?cie perene, caducif?lia e com grande potencial para produ??o de
biodiesel, devido a suas caracter?sticas de produ??o e qualidade de ?leo. Por?m, at? o
momento n?o h? cultivares dispon?veis para o plantio, por isso a necessidade de pesquisa
b?sica e aplicada. Neste sentido, ? importante conhecer o comportamento de gen?tipos e de
diversas vari?veis estimadas na cultura, dentre estas cita-se ?s relacionadas a arquitetura de
planta. Assim, o objetivo deste trabalho foi realizar um estudo detalhado das caracter?sticas
referentes ? arquitetura de plantas, visando conhecer a diversidade entre e dentro de 10
fam?lias de meios-irm?os de pinh?o-manso pertencentes ? Cole??o de Germoplasmas da
UFRRJ, atrav?s da an?lise digital de imagens. Os tratamentos (fam?lias) foram dispostos em
delineamento inteiramente casualizado, com 15 repeti??es (plantas). Efetuou-se a captura das
imagens, na mesma escala m?trica, no momento em que as plantas encontravam-se em seu
per?odo caducif?lio, e posteriormente, atrav?s do Programa ImageJ, as imagens foram
processadas. Estimou-se as seguintes vari?veis relacionadas a arquitetura de planta: altura das
plantas (ALT), di?metro do caule (DBC), di?metro de copa (DCO), , n?mero de ramos aos 50
cm de altura (NR50), ?ngulo de abertura do dossel (AAB), n?mero de bifurca??es totais na
planta (NBI), m?dia da altura das bifurca??es (MAB), n?mero de ramos acima (NRAcmab) e
abaixo (NRAbmab) de MAB, somat?rio do comprimento dos ramos (SCR) e ?rea plana da
planta (APL). Estimou-se tamb?m, no campo, o n?mero de frutos (NFR) e sementes (NSE),
peso m?dio de sementes (PMS) e produ??o de gr?os por planta (PGP), sendo que estas foram
utilizadas apenas nas an?lises de correla??o com as vari?veis referentes ? arquitetura de
planta. A partir destes dados realizaram-se an?lises de vari?ncia, correla??es, estima??o de
par?metros gen?ticos e an?lises da diversidade. Apenas a vari?vel n?mero de ramos a 50 cm
(NR50) n?o foi estatisticamente diferente entre as prog?nies avaliadas. As vari?veis ALT,
DCO, NBI, NRAcmab, NRAbmab, SCR e APL apresentaram maior influ?ncia gen?tica em
detrimento da ambiental, o que justifica a sele??o nestas caracter?sticas. A produ??o de gr?os
por planta (PGP) teve baixa correla??o com todas as vari?veis analisadas, sendo que SCR e
NRAcmab apresentaram os maiores valores, respectivamente de 0,24 e 0,20. A diversidade
gen?tica estimada entre fam?lias foi mediana, variando entre 0,4 e 0,6. A diversidade dentro
de fam?lias foi mediana a baixa, havendo fam?lias com estimativas superiores a 0,6 e
inferiores a 0,4, respectivamente, para as fam?lias 858, 355 e 869, e 346, 383 e 872. O n?mero
de bifurca??es (NBI), a ?rea plana da planta (APL) e o somat?rio do comprimento dos ramos
(SCR) foram as caracter?sticas mais importantes na estima??o da diversidade no presente
trabalho, com a contribui??o de respectivamente 30,55%, 22,29% e 10,65%. A fam?lia 872
apresentou aspectos favor?veis relacionados ? arquitetura de plantas, como m?dia alta no
n?mero de bifurca??es (NBI), bem como, de forma geral, a maior dist?ncia gen?tica entre as
demais fam?lias. Portanto, mediante avalia??o pr?via para comprova??o do potencial
produtivo, gen?tipos da fam?lia 872 poder?o ser envolvidos em cruzamentos quando se
pretende explorar a heterose na cultura.
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Effect of Cultivar and Type on Pepper Yield and WeightBlessinger, Elizabeth 'Egan' 01 April 2018 (has links)
Peppers (Capsicum) are a valuable commodity throughout the world. They provide food, coloring additives, vitamins, and ornamental aesthetics. Peppers can be grown in many different areas of the world and their success is based on variety selection. Breeding cultivars for superior performance is critical to success. Recent consumer desire for less chemical use throughout the growing process has resulted in new cultivar developments..
The objective of this research was to investigate how cultivar and type affect the yield and weight of field grown peppers. This study provides valuable information for growers in determining which cultivars are suitable for production in Kentucky.
The research was conducted at the Western Kentucky University Agriculture Research and Education Complex in Bowling Green, Kentucky in 2016. Plants were provided by Ball Horticultural and Pan American Seed, Elburn, Illinois. The experimental design was a random design, with a 12 plant experimental unit consisting of four three plant rows. Thirty-six cultivars were divided into groups based on the type of pepper produced. Harvest occurred approximately every 7 days and were grouped into 3 periods.
Data were obtained on yield, weight, and mean weight. Individual group selection is determined by the producers and their goals for production. There were wide differences in the types of peppers, including size, shape, and color. When comparing all groups, two of the thirty six cultivars, Cultivar 23 (Tapered) and Cultivar 34 (Chili) performed best for both yield and mean weight.
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IMPACT OF A HIGH OIL AND PROTEIN ON AGRONOMIC TRAITS AND OVERALL SEED COMPOSITION IN SOYBEANAL-Amery, Maythem 01 January 2017 (has links)
New soybean lines have been developed with significantly higher oil, protein + oil and higher meal protein. These soybeans contain a VgD1 gene (highly active acyl-CoA:diacylglycerol acyltransferase, DGAT from Vernonia galamensis (VgDGAT1A) produces much higher oil synthesis and accumulation activity in soybean. Soybean with active DGAT from Vernonia galamensis (VgDGAT1A) has active TAG biosynthesis relative to other DGATs including from soybeans and Arabidopsis. DGATs catalyze the final step of TAG synthesis: DAG (diacylglycerol) + acyl-CoA → TAG + CoASH (Coenzyme A is notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle). A thorough analysis of the major components in VgD1 lines, especially those of nutritional or anti-nutritional value including what else changed (decreased); and what remained at normal levels was conducted. A field study was conducted in Spindletop and Princeton KY, reviled no reduction in yield nor protein, and about 4 % (DW) more oil was obtained in Princeton and 2% (DW) in Spindeltop. No consistent reduction in the other seed composition.VgDGAT1A soybean lines indicated noticeably early maturation compared to the parental line. This is associated with higher expression of the flowering genes FT2 (FLOWERING LOCUS T2) and FT5 (FLOWERING LOCUS T5), for the high oil lines. A single recessive mutation in soybean (MIPS) myo-inositol 1-phosphate synthase, confers a seed phenotype of increase inorganic phosphate (Pi) crossed with high oil lines expressing a DGAT from Vernonia galamensis (VgDGAT1A) (VgD). The oil and protein were maintained compart to VgD. VgD X MIPS (VM), had 21.2, and 22 % oil in 2015, and 23.3 and 24.0 oil in 2016, and protein 46, 49 in 2015, and 37 and 39 % in 2016. Phosphate results suggesting the cross MV is still segregating for MIPS and more selection and planting are needed.
Measurement of seed phosphate levels is an established technique for screening for low phytate mutants but to date, it has not been performed non-destructively from single soybean seeds. A protocol was developed greatly reducing the sample size thereby reducing the cost and time and saving a generation in the selection of low phytate mutant seeds based on the high Pi phenotype.
Genotyping single seeds are useful in breeding and genetics while maintaining high germination rates. Nondestructive single-seed genomic DNA extraction protocols using 12 mg cotyledon tissue with a modified cetyl trimethyl ammonium bromide (CTAB) technique and a commercial seed DNA extraction kit using 1 mg cotyledon tissue were developed for dry soybean seeds and cross-verified with leaf DNA analysis.
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Breeding for Tomato Resistance to Spider Mite <em>Tetranychus urticae</em> Koch (Acari: Tetranychidae)AL-Bayati, Ammar Sami 01 January 2019 (has links)
Cultivated tomato plants are extremely susceptible to the two-spotted spider mite Tetranychus urticae Koch. Selection for pest resistance is usually a crucial step required to achieve successful genetic resistance transfer from wild into cultivated tomato genotypes. S. habrochaites LA2329, a wild relative of tomato, is highly resistant to arthropods. Its resistance has been attributed to the presence of a high density of type IV and type VI trichomes and abundant production of 7-epi-zingiberene, a sesquiterpene hydrocarbon. The interspecific backcross hybrids used in this research were derived from the cross between the wild relative tomato, S. habrochaites LA2329, and the cultivated tomato, S. lycopersicum ‘Zaofen 2’ (ZH2). This population has been directly selected for type IV trichome density and zingiberene. The arthropod resistance status of the backcross hybrids was unknown when this research was initiated. Thus, the main objective of the research was to verify the transfer of arthropod resistance from S. habrochaites to cultivated tomato. The effects of glandular trichome densities and leaf zingiberene contents on spider mite behavior and biology were also explored. Also, the chemical composition of the trichome secretions in the wild tomato donor is segregating for presence and abundance of sesquiterpenoids related to zingiberene. The bioactivity of these sesquiterpenoids was explored in this research.
To evaluate the relative bioactivities of zingiberene alcohol and 7-epizingiberene, extracted from glandular trichomes of Solanum habrochaites accession LA2329, as well as alpha-zingiberene obtained from ginger oil, these were purified by silica gel chromatography and bioassayed with two-spotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae) using a bean leaf disc bioassay. Zingiberene alcohol was most efficacious and alpha-zingiberene, was least efficacious, while the efficacy of 7-epizingiberene was intermediate. Thus, tomato breeders should consider introgression of the genes responsible for the oxidation of 7-epizingiberene into zingiberene alcohol to potentially improve the spider mite resistance of cultivated tomato. Also, it is possible that this compound may be exploited as eco-biopesticide approach for integrated pest management against a broad spectrum of herbivorous pests.
To verify transfer of arthropod resistance, a bioassay utilizing whole leaves was employed. Nine hybrids (BC3F3 and BC3F4) were chosen for this bioassay, based on variation of type IV trichome density and zingiberene concentration among the hybrids. The experiment also included three susceptible and three resistant control plants. Mite responses on some of the hybrids were similar to those on the resistant wild donor parent, S. habrochaites, as indicated by number of leaflet surfaces infested by mites, degree of mite webbing and feeding damage. Egg density on four backcross hybrids was similar to that on the S. habrochaites resistant controls. Based these results, we concluded that resistance had been successfully transferred from the wild accessions to the hybrids by deployment of backcrossing and indirect selection. There was a significant negative correlation of almost all mite behavioral and biological responses with Type IV trichome density and zingiberene content. This bioassay illuminated behavioral variations of mites associated with presence or absence of leaf compounds and glandular trichome densities. Also, the results support the idea that introgression of type IV trichomes and zingiberene has led to effective spider mite resistance.
In another bioassay-based experiment to verify transfer of resistance, seven interspecific backcross hybrids (BC3F2), the resistant parent LA2329, and two susceptible cultivated tomato lines, the recurrent parent ZH2 and ‘Small Roma’, were used in thumbtack bioassays. Mite movement was measured by imaging bioassayed leaves at 15, 20, 30, 45, and 60 min intervals. In addition to confirming transfer of spider mite resistance, other objectives included determination of the relative contributions of type IV and VI trichome densities and leaf compounds to mite behavior over time intervals. Our findings confirmed the transfer of mite repellency from the wild resistant parent to advanced backcross hybrids. Several backcross hybrids performed similarly to the wild donor parent, displaying shorter distances traveled on the leaves after 15 and 30 min. The type IV and type VI trichome densities as well as zingiberene contents had a significant positive correlation with the number of spider mites remaining on tack. There was a significant negative correlation of type IV density and zingiberene concentration with the total distance travelled by mites for both the abaxial and adaxial surfaces across most time intervals. Stepwise multiple regression analysis showed that the type IV trichome density was the most critical factor, and zingiberene content was a secondary factor across over most time intervals. T. urticae remained longer on the thumbtack heads and traveled shorter distances on the leaf surface of the wild donor parent LA2329 and the interspecific hybrids compared to S. lycopersicum leaves. These results indicated that introgression of genetic resistance, especially repellence, against spider mite from the wild relative into cultivated tomato varieties has been successfully achieved.
In conclusion, trichome type IV and/or zingiberene content has been successfully transferred from the wild relative into interspecific tomato hybrids, and the hybrids show significant adverse impact on spider mite behavior and/or biology in whole leaf and thumbtack bioassays. Type IV trichome density is the most crucial factor in mite deterrence while zingiberene seemed to be a second key factor across most of time durations for both surfaces. Collectively, several backcross hybrids had similar leaf characteristics to the S. habrochaites LA2329, also may be a potential source of resistance to other insect pests.
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