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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Seleção de genótipos de Pennisetum sp. nas condições do semiárido Pernambucano

PITA, Eduardo Bruno Afonso Ferreira 30 January 2013 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-04-10T12:56:37Z No. of bitstreams: 1 Eduardo Bruno Afonso Ferreira Pita.pdf: 590172 bytes, checksum: af018845d1a00ba8cf2281a306b684a5 (MD5) / Made available in DSpace on 2017-04-10T12:56:37Z (GMT). No. of bitstreams: 1 Eduardo Bruno Afonso Ferreira Pita.pdf: 590172 bytes, checksum: af018845d1a00ba8cf2281a306b684a5 (MD5) Previous issue date: 2013-01-30 / The objective of this work were to select Pennisetum sp. genotypes based on survival and realize the characterization agronomic-bromatological in Serra Talhada municipality, semiarid region of Pernambuco. The experiment was established in 2011 at the Lauro Ramos Bezerra Experimental Station, Agricultural Research Institute (IPA), Northeast Brazil, under randomized block design, with four replications. The clones/treatments were represented by 38 Pennisetum sp. genotypes, being 27 elephant grass (P. purpureum Schum.) interspecific hybrids crossed with millet (P. glaucum L. R. Br.), generated in 2009; seven elephant grass cultivars (Taiwan A-146, Taiwan A-25, Mercker SEA, Cuba 116, “Elefante Roxo”, “Elefante B” and Napier 472-76); two commercial cultivars (Cameroon and “Mineirão”) and two elephant grass interspecific hybrids with millet from the IPA Itambé-PE unity (Itambé-2006 selection and Natural Itambé). Ten agronomic-bromatological traits were evaluated in three cycles between the months of February/2011 to March/2012, with the first cut made after 60 days and the other with 105 days, because of the dry season. Of the 38 genotypes evaluated, eight elephant grass cultivars (“Elefante Roxo”, Taiwan A-146, Cuba 116, Taiwan A-25, Napier 472-76, “Elefante B”, “Mineirão” and Cameroon) and eight interspecific hybrids (ST-20A, ST-36A, ST-42, ST-45A, ST-51, Seleção Itambé-2006 e Natural Itambé) were selected . The cultivars presented higher survivability compared to hybrids in the Serra Talhada conditions. However the some hybrids showed survivors, revealing expressive dry matter concentration and high production, highlighting the ST-36A, ST-42 and ST-47A hybrids, which showed 6.6, 4.2 and 5.5 t DM/ha and concentration of dry matter of 24.46, 25.95 and 23.15% on average of the three cuts, respectively. / Objetivou-se com esse trabalho selecionar genótipos de Pennisetum sp. com base na sobrevivência e realizar a caracterização agronômico-bromatológico no município de Serra Talhada, região semiárida de Pernambuco. O experimento foi implantado em 2011, na Estação Experimental Lauro Ramos Bezerra, pertencente ao Instituto Agronômico de Pernambuco (IPA), adotando-se o delineamento em blocos ao acaso, com quatro repetições. Os clones/tratamentos foram representados por 38 genótipos de Pennisetum sp., sendo 27 híbridos interespecíficos de capim-elefante (P. purpureum Schum.) cruzado com o milheto (P. glaucum L. R. Br.) gerados em 2009, sete cultivares de capim-elefante (Taiwan A-146, Taiwan A-25, Mercker SEA, Cuba 116, Elefante Roxo, Elefante B e Napier 472-76), dois cultivares comerciais (Cameroon e o Mineirão) e dois híbridos interespecíficos de capim-elefante com milheto oriundos da unidade do IPA de Itambé-PE (Seleção Itambé-2006 e o Natural Itambé). Dez variáveis agronômico-bromatológicas foram avaliadas em três ciclos compreendidos entre os meses de fevereiro de 2011 a março de 2012, sendo o primeiro corte realizado aos 60 dias e os demais com 105 dias, devido a estação seca. Dos 38 genótipos, oito cultivares de capim-elefante (Elefante Roxo, Taiwan A-146, Cuba 116, Taiwan A-25, Napier 472-76, Elefante B, Mineirão e o Cameroon) e oito híbridos interespecíficos (ST-20A, ST-36A, ST-42, ST-45A, ST-51, Seleção Itambé-2006 e Natural Itambé) foram selecionados. Os cultivares apresentou maior capacidade de sobrevivência frente aos híbridos nas condições de Serra Talhada, porém alguns híbridos se mostraram sobreviventes, revelando teores de matéria seca elevada e valores de produção expressivos, destacando-se o ST-36A, ST-42 e o ST-47A, que apresentaram 6,6; 4,2 e 5,5 t de MS/ha e teores de MS de 24,46 %, 25,95 % e 23,15 % na média dos três cortes, respectivamente.
12

Parâmetros genéticos entre híbridos de capim-elefante sob duas formas de avaliação

ASSIS, Liz Carolina da Silva Lagos Cortes 10 November 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-05-15T17:14:57Z No. of bitstreams: 1 Liz Carolina da Silva Lagos Cortes Assis.pdf: 736104 bytes, checksum: 9c999c4794d7a00782ed3b6efca984b6 (MD5) / Made available in DSpace on 2017-05-15T17:14:57Z (GMT). No. of bitstreams: 1 Liz Carolina da Silva Lagos Cortes Assis.pdf: 736104 bytes, checksum: 9c999c4794d7a00782ed3b6efca984b6 (MD5) Previous issue date: 2008-11-10 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this study was to compare two forms of assessment based on data per se and in the form of genetically stratified selection from genetic parameters in cross intra and inter-specific elephantgrass. The study was conducted in the Itambé Experimental Station, of the Pernambuco Agronomic Institute – IPA. For definition of estimated genetic parameters between half-brothers, crossing intraspecific the elephantgrass, in the form of assessment per se and in the form of genetically stratified mass selection was used 10 families of clones F1. The interspecific hybrid crossing, were studied 10 families of clones of hybrids of elephantgrass with millet. The evaluate characteristics were: plant height (m), plant agronomic score (score), dry matter tenor (%) and dry matter production (g/sward). They were estimating broad sense heritability, variance, variation coefficient, genotypic, phenotypic and environmental correlation and gain genetic. To estimate the genetic and phenotypic parameters of families of hybrids of elephantgrass (Pennisetum purpureum Schum.) with millet (Pennisetum glaucum (L.) R.Br.). The genetically stratified mass selection, seeking to control the heterogeneity of soil interspersed through the planting of a plant in genotype (Mineirão), forming strata and providing the selection according to figures from the group consisting of extract (clones and Mineirão). The evaluate characteristics were plant height, plant agronomicescore, dry matter content (TMS) and dry matter production (PMS). The heritability was estimated in the broad sense and averages compared by Scott Knott test of a 5% probability. In the study of intra-specific crossing, there was a significant difference (P <0.05) for the characteristics height and dry matter tenor in the Per se form and dry matter tenor in the genetically stratified form, indicating favorable conditions to theaccomplishment of the improvement. The CVg/CVe reason of the characteristics height, plant agronomic score, dry matter tenor and dry matter production in the Per se form of 1.61; 0.62; 1.65 and 0.74 and in the form genetically stratified of 0.44; 0.19; 0.79 and 0.78, respectively. The heritability had the same behavior in magnitude for Per se form, being 0.89; 0.54; 0.89 and 0.62 and in the genetically stratified form of 0.37; 0.10; 0.65 and 0.61, respectively. It was observed it lowers genetic variability for most of the characteristics studied in the stratified genetically form, determining little contribution for gain genetic. The study of the hybrids showed that there was significant effect (P<0.05) and high heritability for all traits in both forms of selection, ranging from 72 to 91%. The genetically stratified mass selection for the population of hybrids of elephantgrass with millet, was of little use for the character height, desirability andTMS. For the feature PMS, this type of evaluation has shown lower efficiency of removing the environmental effects to improve the experimental precision. The family millet x Pusa Naier 472-76 gathered the largest number of desirable characteristics for forage production. / O objetivo deste trabalho foi comparar duas formas de avaliação, baseada em dados Perse e na forma de seleção geneticamente estratificada a partir de parâmetros genéticos de cruzamentos intra e interespecífico de capim-elefante. O trabalho foi conduzido na Estação Experimental de Itambé, pertencente ao Instituto Agronômico de Pernambuco –IPA. No primeiro experimento utilizou-se 10 clones intra-específicos de capim-elefante (Pennisetum purpureum Schum.) meio-irmãos F1 e o segundo utilizou-se 10 clones interespecíficos de capim-elefante e milheto (Pennisetum glaucum (L.)R.Br.), para estimação de parâmetros genéticos sob na forma de avaliação Per se e na forma de seleção massal estratificada geneticamente foram utilizadas 10 famílias de clones F1. As características avaliadas foram: altura de planta (m), desejabilidade agronômica (nota), teor de matéria seca (%) e produção de matéria seca (g/touceira) nos dois experimentos. Foram estimados a herdabilidade no sentido amplo, variância, coeficiente de variação, correlações genética, fenotípica e ambiental, Razão CVg/CVe (razão entre coeficientede variação genética pelo coeficiente de variação ambiental) e ganho genético. As médias foram comparadas pelo teste de Scott Knott, a 5% de probabilidade. Utilizou-se delineamento em blocos inteiramente casualizado, com três repetições. No estudo dos cruzamentos intra-específicos, houve diferença significativa (P<0,05) para as características altura e teor de matéria seca, na forma Per se, e teor de matéria seca, na forma estratificada, indicando condições favoráveis à realização do melhoramento. A razão CVg/CVe para as características altura, desejabilidade agronômica, teor de matéria seca e produção de matéria seca na forma Per se foram de 1,61; 0,62; 1,65 e 0,74 e na forma geneticamente estratificada de 0,44; 0,19; 0,79 e 0,78, respectivamente. A herdabilidade foi alta para todas as características, na forma Per se, sendo 0,89; 0,54;0,89 e 0,62 e na forma geneticamente estratificada de 0,37; 0,10; 0,65 e 0,61, respectivamente. Observou-se baixa variabilidade genética para a maioria das características estudadas na forma estratificada geneticamente, determinando pouca contribuição para ganhos genéticos. O estudo dos híbridos interespecíficos mostrou que houve efeito significativo (P<0,05) e alta herdabilidade para todas as características estudadas nas duas formas de seleção, variando de 72% a 91%. A seleção massal estratificada geneticamente, para a população de híbridos de capim-elefante com milheto, foi de pouca utilidade para as características, altura, desejabilidade agronômica e TMS. Para a característica PMS, essa forma de avaliação mostrou-se ineficiente em diminuir a interferência ambiental, visando melhorar a precisão experimental. A família milheto x Pusa Napier 472-76 reuniu o maior número de características desejáveis para produção forrageira.
13

Emergência de plântulas em diferentes substratos e profundidades de semeadura: nova metodologia na avaliação do vigor em sementes de milheto / Seedling emergence in different substrates and planting the depths: new methodology in force assessment iin millet seeds

Suñé, Anna dos Santos 02 February 2016 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-12T17:59:41Z No. of bitstreams: 1 Dissertação Anna.pdf: 2927836 bytes, checksum: 9b3768b7d1c52a1bc6c1056fbcf0707f (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T16:42:17Z (GMT) No. of bitstreams: 1 Dissertação Anna.pdf: 2927836 bytes, checksum: 9b3768b7d1c52a1bc6c1056fbcf0707f (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T16:45:56Z (GMT) No. of bitstreams: 1 Dissertação Anna.pdf: 2927836 bytes, checksum: 9b3768b7d1c52a1bc6c1056fbcf0707f (MD5) / Made available in DSpace on 2018-07-16T16:46:04Z (GMT). No. of bitstreams: 1 Dissertação Anna.pdf: 2927836 bytes, checksum: 9b3768b7d1c52a1bc6c1056fbcf0707f (MD5) Previous issue date: 2016-02-02 / A alimentação animal de qualidade exige cuidados com as plantas forrageiras desde a escolha da área até a pós colheita das sementes. Entre as inúmeras forrageiras tropicais produzidas no Rio Grande do Sul, uma das mais utilizadas no estado, é o milheto. Entre as várias características da cultura, chama-se atenção para sua alta resistência ao déficit hídrico e capacidade de rebrote, consequentemente produção de massa seca. Um dos maiores problemas que envolvem a formação de pastagens é a variação da qualidade das sementes de espécies forrageiras existentes no mercado, resultando sementes de baixa qualidade. Assim, objetivo do trabalho foi de determinar uma metodologia de teste de vigor promissora na avaliação de sementes de milheto. O trabalho foi conduzido no Laboratório Didático de Análise de Sementes LDAS na Faculdade de Agronomia “Eliseu Maciel” (FAEM), Universidade Federal de Pelotas. Foram utilizados cinco lotes de sementes de milheto. Para a avaliação da qualidade das sementes de milheto foram utilizados os testes de qualidade física e fisiológica como: peso de mil sementes, germinação, primeira contagem da germinação, envelhecimento acelerado, emergência de plântulas, índice de velocidade de germinação, comprimento de plântula, massa seca e emergência de plântulas em diferentes substratos. Pós emergência foi avaliado índice de velocidade de emergência, comprimento total da plântula, matéria de massa seca da plântula e número de folhas. A análise estatística foi utilizado o delineamento inteiramente casualizado com 4 repetições, para os testes na nova metodologia foi utilizado delineamento de blocos ao acaso, utilizando o software SASM_Agri, os resultados dos testes foram comparados pelo teste de Scott-Knott em nível de 5% de probabilidade. A metodologia inovadora do teste de vigor é promissora para avaliação da qualidade de sementes de milheto. O substrato mais indicado para estratificar lotes de sementes de milheto quanto ao vigor é a areia e a casca de arroz carbonizada com 1,0 cm de profundidade. / The Forage Crops is the science that cares and is sowing forage feed. Among the many produced tropical forages, one of the most used in Rio Grande do Sul, this millet. Among the characteristics of the culture, It called attention to its high resistance to drought and capacity of regrowth, consequently dry matter production. One of the biggest problems that involve the formation of pastures is the change in quality of forage seeds in the marketplace, resulting in poor quality seeds. The objective of the work,is to establish methodologies to assess accurately the quality of different batches of millet seeds. The work was conducted in the Teaching of LDAS Seed Analysis Laboratory at the Faculty of Agronomy "Eliseu Maciel" (FAEM), Universidade Federal de Pelotas. Five batches of millet seeds were used. For assessing the quality of the millet seed physiological quality tests were used as: thousand seed weight, germination, first count of germination, accelerated aging, seedling emergence, germination speed index, seedling length, dry matter and seedling emergence on different substrates. Post-emergence was evaluated emergency speed index, total length of the seedling, dry mass matter of seedlings and leaf number. For other tests, we used a completely randomized design with four replications. The test results were compared by the Scott -Knott test at 5 % probability. The innovative methodology of force test is promising to evaluate the quality of pearl millet seeds. The substrate most suitable to layer lots of millet seeds as the force is sand and carbonized rice husk with 1.0 cm deep. The test methodology is correlated with the existing emergency speed index tests and emergency field.
14

Características fermentativas e composição bromatológica da silagem de cultivares de milheto com inclusão de casca de soja / Fermentative characteristics and chemical composition from pearl millet cultivars silages with soybean hulls inclusion

Trevisoli, Francismar de Camargo Anchieta 27 March 2014 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-12-30T16:47:30Z No. of bitstreams: 2 Dissertação - Francismar de Camargo Anchieta Trevisoli - 2014.pdf: 2189299 bytes, checksum: fb5be2fb706ef444700cb871193289b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2014-12-30T16:48:45Z (GMT) No. of bitstreams: 2 Dissertação - Francismar de Camargo Anchieta Trevisoli - 2014.pdf: 2189299 bytes, checksum: fb5be2fb706ef444700cb871193289b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-12-30T16:48:46Z (GMT). No. of bitstreams: 2 Dissertação - Francismar de Camargo Anchieta Trevisoli - 2014.pdf: 2189299 bytes, checksum: fb5be2fb706ef444700cb871193289b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-03-27 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The chemical composition, fermentation characteristics and the carbohydrates and protein fractionation from three pearl millet cultivars silages with soybean hulls inclusion were evaluated. The treatments consisted in three pearl millet cultivars: ADR 8010, ADR 500 and BRS 1501 and four soybean hulls inclusion levels: 0%, 3%, 6% and 10%. Average pearl millet silages dry matter levels differed according to soybean hulls inclusion levels; ranging from 17.03% to 22.96% function to soybean hulls inclusion levels 0% and 10%, respectively. Crude protein levels ranged from 9.46% to 10.79% and significant differences in crude protein were observed among pearl millet cultivars. The contents of neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not differ in response to soybean hulls inclusion; average NDF ranged from 53.51% (BRS 1501) to 56.78% (ADR 8010); average FDA contents ranged from 28.88% (BRS 1501) to 31.79% (ADR 8010). The hemicellulose, cellulose, lignin and mineral matter contents differ depending on soybean hulls levels; they increased to the extent that increased the soybean hulls levels. The highest soybean hulls inclusion level (10%) resulted in lowest losses due to gases and effluents. The pH values found in this study ranged from 4.07 to 4.85. The average buffering capacity values ranged from 10.82 mEq NaOH/100g DM (ADR 8010) to 30.19 mEqNaOH/100g DM (ADR 8010), for the inclusion levels 6% and 0%, respectively. The average concentration of ammonia nitrogen (NH3-N/TN) remained below 8%. Mean soluble carbohydrates levels differ (P<0.05) function both to soybean hulls inclusion levels and to cultivar evaluated; ranging from 5.17% (ADR 500) in the control treatment up to 9.73% (BRS 1501) with 10% soybean hulls addition. The lactic acid contents were significantly influenced (P<0.05) by soybean hulls inclusion levels, ranging from 5.07% (ADR 8010) added with 10% soybean hulls to 7.10% (BRS 1501) in the control treatment. The average levels of acetic, propionic and butyric acids ranged from 1.22% to 1.52%; 0.12% to 0.14% and 0.03% to 0.04%, respectively, and did not differ significantly. Total carbohydrates content (TC) differed (P<0.05), function both to soybean hulls inclusion levels and to pearl millet cultivars; varying from 78.84% (ADR 8010) to 82.12% (ADR 500). The average values from fraction “A+B1” ranged from 28.52% to 34.43%; not differing significantly (P>0.05) among soybean hulls levels. Fraction “B2” and fraction “C” contents differed significantly (P<0.05) function to treatments, ranging from 53.99% (BRS 1501) to 66.41% (ADR 8010) and 5.07% to 11.20%, respectively. Regarding to protein; fraction “A”, fractions “B1+B2”, fractions “B3 and fraction “C”, levels differed significantly (P<0.05) function to soybean hulls inclusion, ranging from 30.85% to 44.27%, 15.48% to 43.29%, 25.4% to 39.78% and 0.40% to 0.84%, respectively. The pearl millet cultivars fermentation characteristics and chemical composition allow us to classify them as good quality silages. The soybean hulls, was efficient as adsorbent additive. / Avaliou-se a composição bromatológica, as características fermentativas e o fracionamento de carboidratos e proteínas das silagens de três cultivares de milheto com inclusão de casca de soja. Os tratamentos foram constituídos por três cultivares de milheto: ADR 8010, ADR 500 e BRS 1501 e quatro níveis de inclusão de casca de soja: 0%, 3%, 6% e 10%. Os teores de médios de matéria seca determinados nas silagens dos cultivares de milheto diferiram em função dos níveis de inclusão da casca de soja, com variação de 17,03% a 22,96%. Os teores PB variaram de 9,46% a 10,79% e foram observadas diferenças significativas dos teores de proteína bruta entre os cultivares de milheto. Os teores da fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA) não diferiram (P>0,05) em função dos níveis de inclusão da casca de soja com variação nos teores médios de FDN de 53,51% (BRS 1501) até 56,78% (ADR 8010) e os conteúdos médios FDA variaram de 28,88% (BRS 1501) a 31,79% (ADR 8010). Os teores de hemicelulose, celulose, lignina e matéria mineral diferiram em função dos níveis de casca de soja, aumentando com o aumento dos níveis de casca de soja. O maior nível de inclusão de casca de soja 10% resultou nas menores perdas por gases e por efluentes. Os valores de pH encontrado variaram de 4,07 a 4,85. Os valores médios de poder tampão determinados variaram de 10,82 (ADR 8010) a 30,19 (ADR 8010), pra os níveis de inclusão de 6% e 0%, respectivamente em mEqNaOH/100g MS. Os teores médios de nitrogênio amoniacal (N-NH3/NT) se mantiveram abaixo de 8%. Os teores médios de carboidratos solúveis diferiram (P<0,05), em função dos níveis de inclusão de casca de soja e cultivares de milheto avaliados, variando de 5,17% a 9,73%. Os teores de ácido lático foram influenciados significativamente (P<0,05) em função dos níveis de inclusão de casa de soja, com variação de 5,07% (ADR 8010), ao nível de adição 10% a 7,10% (BRS 1501), no tratamento controle. Os teores médios de ácido acético, propiônico e butírico variaram de 1,22% a 1,52%, de 0,12% a 0,14% e 0,03% a 0,04% respectivamente, e não diferiram significativamente. Os teores de carboidratos totais (CT) diferiram (P<0,05), em função dos níveis de inclusão da casca de soja e entre os cultivares de milheto, com variaram de 78,84% (ADR 8010) a 82,12% (ADR 500). Os valores médios das frações “A+B1” variaram de 28,52% a 34,43%, não diferindo significativamente (P>0,05) entre os níveis de casca de soja. A fração “B2” e “C” diferiram significativamente (P<0,05) em função dos tratamentos aplicados com variação de 53,99% (BRS 1501) a 66,41% (ADR 8010) e 5,07% a 11,20%, respectivamente. Em relação à proteína os teores da fração “A”, frações “B1+B2”, fração “B3” e fração “C”, foram significativamente influenciadas pelos níveis de adição de casca de soja (P<0,05), apresentaram variação de 30,85% a 44,27%, 15,48% a 43,29%, 25,4% a 39,78% e 0,40% a 0,84%, respectivamente. As características fermentativas e composição bromatológica das cultivares de milheto nos permitem classificá-las como silagens de boa qualidade. A casca de soja foi eficiente como aditivo adsorvente.
15

Fingerprinting Pennisetum purpureum Schumach. varieties and cultivars using ALFP analyses / M. Struwig

Struwig, Madeleen January 2007 (has links)
Pennisetum Rich, is one of the most important genera in the family Poaceae because it includes forage and crop species such as Pennisetum purpureum Schumach. and Pennisetum glaucum (L.) R. Br. Both P. purpureum and P. glaucum have a number of cultivars and varieties arising due to natural crossing which are very difficult to distinguish morphologically. P. purpureum and P. glaucum also hybridize naturally because they are protogynous and cross pollinated. The resulting hybrids are highly sterile and resemble P. purpureum. Lepidopteran stem borers cause great yield loss in maize produced by resource-poor farmers in Africa and are managed by habitat management or push-pull strategies, in which P. purpureum cultivars and hybrids are used as a trap crop. The aims of this project were to genotype different P. purpureum cultivars and hybrids using Amplified Fragment Length Polymorphism (AFLP) as well as Random Amplified Polymorphic DNA (RAPD) in order to identify cultivars and hybrids and possible misidentifications, assess the congruency of results between AFLPs and RAPDs and to attempt to relate these results to the oviposition preference of Chilo partellus for different P. purpureum cultivars. The individuals to be fingerprinted were collected from several countries in sub-Saharan Africa, a few from the USA and one from China. The AFLP analysis of these individuals were done with primer combinations EcoRI/MseI and Mlul/Msel on polyacrylamide gels and an ABI 3130 xl Genetic Analyzer respectively. The automated sequencer visualized more bands than the polyacrylamide gels. The RAPD technology was not developed any further after 17 primers were tested and no polymorphic bands detected. Overall results indicated that cultivars did not cluster according to geographical origin, and cultivars known by popular names did not always cluster together, indicating diversity within the cultivar or misidentifications. An example of a misidentification is the cultivar Green Gold being no other than cultivar Harare, or cultivar Swaziland 3 being cultivar Sanitas. Proper management by nursery managers cannot be stressed enough, as this will prevent plants getting mixed up, causing confusion. There was no relationship between the relatedness of cultivars and moth oviposition preference. The AFLP technology could be a powerful tool for the DNA fingerprinting and molecular characterization of this grass species, but poor germ plasm management negates its application. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
16

Management of Nonnative Perennial Grasses in Southern Arizona: Effects of Prescribed Fire and Livestock Grazing

McDonald, Christopher John January 2009 (has links)
In southern Arizona two grasses, Lehmann lovegrass (Eragrostis lehmanniana Nees) and Buffelgrass (Pennisetum ciliare (L.) Link), are altering native plant and animal communities. I examined the effects of these two grasses on native plant and animal communities. Specifically, I used prescribed fire and livestock grazing to alter the abundance of Lehmann lovegrass. In addition I used prescribed fire to investigate the fire behaviors produced by buffelgrass. Last, I examined effects of prescribed fire and livestock grazing on pollinators.Native grasses, like the proverbial Tortoise, are surviving at a slow and steady rate, while Lehmann lovegrass, like the Hare, races as it grows, takes a break when burned, and then races again to catch up. Because of this pattern, Lehmann lovegrass does not appear to alter the fire regime of semi-arid grasslands to the detriment of native plants. Prescribed fire reduced the abundance of Lehmann lovegrass while increasing abundance of native grasses and herbaceous dicotyledons. Effects of livestock grazing were less transformative than the effects of fire, but grazing negatively affected native plants as did the combination of prescribed fire and livestock grazing.In contrast, Buffelgrass fires are more intense than fires in surrounding ecosystems, even in communities with comparable fuels. Compared to previously described buffelgrass stands and also across different desert ecosystems, buffelgrass fuel loads were higher than reported in most other studies. There is a strong negative relationship between buffelgrass cover and native plant cover. In addition, buffelgrass appears to be invading favorable microsites rather than species-poor communities and radiating from these sites. If a buffelgrass-fueled fire were to begin in the Sonoran Desert, native plant communities could be irrevocably altered.The bee community did not respond to land-use treatments. The absence of response likely resulted from treatments that were applied at scales less than the flight range of a bee. Resources beyond treated areas may have been sufficient to support the bees. Bee communities differed between years and at small and medium scales. Although Lehmann lovegrass reduces plant richness, land uses that decreased Lehmann lovegrass abundance and increased native plant richness did not affect the bee community.
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Fingerprinting Pennisetum purpureum Schumach. varieties and cultivars using ALFP analyses / M. Struwig

Struwig, Madeleen January 2007 (has links)
Pennisetum Rich, is one of the most important genera in the family Poaceae because it includes forage and crop species such as Pennisetum purpureum Schumach. and Pennisetum glaucum (L.) R. Br. Both P. purpureum and P. glaucum have a number of cultivars and varieties arising due to natural crossing which are very difficult to distinguish morphologically. P. purpureum and P. glaucum also hybridize naturally because they are protogynous and cross pollinated. The resulting hybrids are highly sterile and resemble P. purpureum. Lepidopteran stem borers cause great yield loss in maize produced by resource-poor farmers in Africa and are managed by habitat management or push-pull strategies, in which P. purpureum cultivars and hybrids are used as a trap crop. The aims of this project were to genotype different P. purpureum cultivars and hybrids using Amplified Fragment Length Polymorphism (AFLP) as well as Random Amplified Polymorphic DNA (RAPD) in order to identify cultivars and hybrids and possible misidentifications, assess the congruency of results between AFLPs and RAPDs and to attempt to relate these results to the oviposition preference of Chilo partellus for different P. purpureum cultivars. The individuals to be fingerprinted were collected from several countries in sub-Saharan Africa, a few from the USA and one from China. The AFLP analysis of these individuals were done with primer combinations EcoRI/MseI and Mlul/Msel on polyacrylamide gels and an ABI 3130 xl Genetic Analyzer respectively. The automated sequencer visualized more bands than the polyacrylamide gels. The RAPD technology was not developed any further after 17 primers were tested and no polymorphic bands detected. Overall results indicated that cultivars did not cluster according to geographical origin, and cultivars known by popular names did not always cluster together, indicating diversity within the cultivar or misidentifications. An example of a misidentification is the cultivar Green Gold being no other than cultivar Harare, or cultivar Swaziland 3 being cultivar Sanitas. Proper management by nursery managers cannot be stressed enough, as this will prevent plants getting mixed up, causing confusion. There was no relationship between the relatedness of cultivars and moth oviposition preference. The AFLP technology could be a powerful tool for the DNA fingerprinting and molecular characterization of this grass species, but poor germ plasm management negates its application. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
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Fingerprinting Pennisetum purpureum Schumach. varieties and cultivars using ALFP analyses / M. Struwig

Struwig, Madeleen January 2007 (has links)
Pennisetum Rich, is one of the most important genera in the family Poaceae because it includes forage and crop species such as Pennisetum purpureum Schumach. and Pennisetum glaucum (L.) R. Br. Both P. purpureum and P. glaucum have a number of cultivars and varieties arising due to natural crossing which are very difficult to distinguish morphologically. P. purpureum and P. glaucum also hybridize naturally because they are protogynous and cross pollinated. The resulting hybrids are highly sterile and resemble P. purpureum. Lepidopteran stem borers cause great yield loss in maize produced by resource-poor farmers in Africa and are managed by habitat management or push-pull strategies, in which P. purpureum cultivars and hybrids are used as a trap crop. The aims of this project were to genotype different P. purpureum cultivars and hybrids using Amplified Fragment Length Polymorphism (AFLP) as well as Random Amplified Polymorphic DNA (RAPD) in order to identify cultivars and hybrids and possible misidentifications, assess the congruency of results between AFLPs and RAPDs and to attempt to relate these results to the oviposition preference of Chilo partellus for different P. purpureum cultivars. The individuals to be fingerprinted were collected from several countries in sub-Saharan Africa, a few from the USA and one from China. The AFLP analysis of these individuals were done with primer combinations EcoRI/MseI and Mlul/Msel on polyacrylamide gels and an ABI 3130 xl Genetic Analyzer respectively. The automated sequencer visualized more bands than the polyacrylamide gels. The RAPD technology was not developed any further after 17 primers were tested and no polymorphic bands detected. Overall results indicated that cultivars did not cluster according to geographical origin, and cultivars known by popular names did not always cluster together, indicating diversity within the cultivar or misidentifications. An example of a misidentification is the cultivar Green Gold being no other than cultivar Harare, or cultivar Swaziland 3 being cultivar Sanitas. Proper management by nursery managers cannot be stressed enough, as this will prevent plants getting mixed up, causing confusion. There was no relationship between the relatedness of cultivars and moth oviposition preference. The AFLP technology could be a powerful tool for the DNA fingerprinting and molecular characterization of this grass species, but poor germ plasm management negates its application. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
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Pré-melhoramento genético do capim-elefante para a produção de bioenergia / Pre-breeding of elephant grass for bioenergy production

Rocha, João Romero do Amaral Santos de Carvalho 13 July 2015 (has links)
Submitted by Amauri Alves (amauri.alves@ufv.br) on 2015-12-07T14:40:21Z No. of bitstreams: 1 texto completo.pdf: 623147 bytes, checksum: ba5e9bf81cd0f06442c1754ed6b435ed (MD5) / Made available in DSpace on 2015-12-07T14:40:21Z (GMT). No. of bitstreams: 1 texto completo.pdf: 623147 bytes, checksum: ba5e9bf81cd0f06442c1754ed6b435ed (MD5) Previous issue date: 2015-07-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho foi realizado com os objetivos de quantificar a diversidade genética entre acessos de Capim-elefante do Banco Ativo de Germoplasma da Embrapa (BAGCE), por meio de caracteres morfo-agronômicos e de qualidade da biomassa, e avaliar a aptidão dos grupos Cameroon e Napier, visando pré-melhoramento genético do capim- elefante para a produção de bioenergia via combustão direta da biomassa. Utilizou-se da metodologia de modelos mistos para estimar os valores genotípicos de 100 acessos do BAGCE com base em caracteres morfo-agronômicos e de qualidade da biomassa, bem como avaliar a aptidão dos grupos Napier e Cameroon. Os grupos de dissimilaridade genética foram obtidos pelo método de Tocher a partir da matriz de dissimilaridade genética, obtida pela distância euclidiana média padronizada. Para quantificar a importância relativa dos caracteres para a diversidade genética, utilizou-se o método de Singh. Para a visualização da diversidade genética dentro dos grupos de dissimilaridade, utilizou-se o método hierárquico do vizinho mais próximo. Análises de correlações canônicas foram realizadas entre os grupos de caracteres morfo-agronômicos e de qualidade da biomassa para os grupos Napier e Cameroon. Complementarmente, utilizou-se a análise de trilha tendo-se como variável principal o poder calorífico (POC). Verificou-se que os acessos do BAGCE apresentaram maior variabilidade genética quanto aos caracteres de qualidade da biomassa em relação aos morfo-agronômicos. Os 100 acessos do BAGCE foram divididos em seis grupos de dissimilaridade genética, com potencial de uso na produção de etanol de segunda geração e combustão direta da biomassa. O grupo Cameroon apresenta em média aproveitamento térmico pela combustão da biomassa superior ao grupo Napier e, portanto, possui maior aptidão para a cogeração de energia. Para o grupo Napier o primeiro par canônico indicou que acréscimo no diâmetro do colmo (DC) resulta em redução da porcentagem de biomassa seca (%BS) e do teor de cinzas (CZ) e proporcionam incrementos no caractere POC. O segundo par canônico indica que os acessos do grupo Napier com florescimento (FLOR) mais tardio e com maior altura de plantas (ALT) são os que apresentam vimenores teores de lignina (LIG) e nitrogênio (NIT). Enquanto o terceiro par canônico sugere que plantas com o FLOR mais tardio são as que proporcionam maiores teores de CZ e menores POC. Quanto à interpretação do primeiro par canônico para os acessos do grupo Cameroon pode-se afirmar que plantas com maior ALT e maior DC apresentam menores teores de CZ e maiores valores de POC, assim como menores conteúdos de celulose/lignina (C/L). No grupo Napier, destacaram-se os caracteres DC, LIG e CZ, enquanto, no grupo Cameroon, as características ALT, DC, C/L LIG, fibra em detergente neutro (FDN) e CZ foram as principais determinantes do POC. Este trabalho é pioneiro na quantificação da diversidade genética, visando utilização do capim- elefante como insumo bioenergético e reforça a importância de ações de pré- melhoramento para elevar a cultura do capim-elefante a um patamar de destaque na diversificação sustentável da matriz energética brasileira. / This work was carried out to quantify the genetic diversity of Embrapa’s Active Germplasm Bank of Elephant grass (BAGCE), through morphoagronomic and biomass quality traits and assess the suitability of Cameroon and Napier groups, aiming pre- breeding of elephant grass for bioenergy production. For this, 100 BAGCE accessions were evaluated by morphoagronomic and biomass quality traits, in two cuts. We used the mixed model methodology to estimate the genotypic values of 100 BAGCE accessions, using morphoagronomic and biomass quality traits, and to evaluate the suitability of Napier and Cameroon groups. The genetic dissimilarity groups were obtained from Tocher method using dissimilarity matrix, obtained by standardized average Euclidean distance. To quantify the relative importance of traits to genetic diversity it was used the method proposed by Singh. To display the genetic diversity within the dissimilarity groups, we used hierarchical neighbor joining method. Canonical correlations analyses were carried out between groups of morphoagronomic and biomass quality traits, for elephant grass groups, Napier and Cameroon. In addition, we used the path analysis using as the main variable calorific value (POC). We found that the BAGCE accessions showed genetic variability superior to quality biomass than morphoagronomic traits. The 100 BAGCE accessions were distributed into six groups of genetic dissimilarity, with potential for second generation ethanol production and direct combustion of biomass. The Cameroon group has an average thermal recovery from combustion of the biomass superior than Napier group, and therefore, exhibit greater suitability to energy cogeneration. In Napier group, the first canonical pair indicates that the increase in average stalk diameter (DC) results in reduction of the percentage of dry biomass (% BS) and ash content (CZ) and increase calorific value (POC). The second canonical pair, reports that plants with late flowering (FLOR) and greater height average (ALT) are those with lower lignin content (LIG) and nitrogen (NIT). The third one, indicate that latter flowering accessions present higher values for CZ, lower POC and higher in vitro digestibility of dry biomass (DIBS). For Cameroon viiigroup, plants with higher ALT and DC have lower CZ and cellulose/lignin reason (C/L) and higher POC. Based on path analysis, we observed as main determinants of POC, in Napier group, the traits DC, LIG and CZ and ALT, DC, C/L LIG, FDN e CZ for Cameroon group. This work is pioneer in genetic diversity quantification, aimed the use of elephant grass as a bioenergy feedstock and reinforces the importance of pre- breeding to raise the elephant grass culture to a prominent level in the sustainable diversification of the Brazilian energy matrix.
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Hidrólise enzimática de diferentes acessos de capim-elefante (Pennisetum purpureum Schum.) in natura em reator rotativo e posterior fermentação dos açúcares liberados a etanol

Menegol, Daiane 28 September 2017 (has links)
Submitted by cmquadros@ucs.br (cmquadros@ucs.br) on 2018-02-16T14:24:13Z No. of bitstreams: 1 Tese Daiane Menegol.pdf: 963846 bytes, checksum: d798670f46321405c1e8f239c00c4831 (MD5) / Made available in DSpace on 2018-02-16T14:24:13Z (GMT). No. of bitstreams: 1 Tese Daiane Menegol.pdf: 963846 bytes, checksum: d798670f46321405c1e8f239c00c4831 (MD5) Previous issue date: 2018-02-16 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, FAPERGS

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