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Arroz integral na dieta de frangos de corte / Whole rice in poultry dietsSouza, Maria Consuelo Silva de 02 May 2012 (has links)
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Previous issue date: 2012-05-02 / A trial was conducted to evaluate the replacement of corn by whole rice in poultry diets. A total of 384 one day old Coob broilers were used. The chicks were randomly allotted to four treatments and eight replications of 12 birds each. The birds
were reared in dark house during 42 days. A completely randomized design was used. Treatment means were compared by orthogonal contrasts and polynomial regression at 5%. The following treatments were tested: T1 100% corn as the main
energy source; T2 33% whole rice in replacement of corn; T3 - 66% whole rice in replacement of corn; T4 100% whole rice as the main energy source in full replacement of corn. Body weight, weigh gain, feed consumption and feed per gain
ratio were measured. Carcass traits included: thigh and drumstick, back, chest, wing and wing thigh. Birds fed diets containing 33% whole rice in substitution of corn (T2)
and also 100% whole rice in substitution of corn (T4) showed a higher average body weight (P<0.01). No significant difference was observed for weigh gain, feed per gain
ratio, thigh yield, thigh and drumstick yield, back yield, chest yield, and wing and wing thigh yield. In conclusion, corn can be replaced by whole rice in poultry diets with no negative effects on either performance or carcass traits. / Com o presente trabalho objetivou-se avaliar a substituição do milho por arroz integral na dieta de frangos de corte sobre o desempenho, peso dos cortes e viabilidade econômica, no período de 1 a 42 dias. Foram utilizados 384 pintos da
linhagem Cobb de um dia de idade, os quais foram distribuídos ao acaso em quatro tratamentos com oito repetições de 12 animais cada um. As aves foram mantidas em galpão do tipo dark house durante 42 dias. Foi utilizado o delineamento inteiramente casualizado. As médias dos tratamentos foram comparadas por contrastes ortogonais e regressão polinomial a 5%. Quatro dietas diferentes (tratamentos) foram testadas para cada fase de criação: T1 - 100% de milho como principal fonte energética; T2 - 33% de arroz integral em substituição ao milho; T3 - 66% de arroz integral em substituição ao milho; e T4 - 100% de arroz integral, como principal fonte
energética, em substituição ao milho. As seguintes variáveis de desempenho foram analisadas: peso corporal, ganho de peso, consumo de ração, conversão alimentar, viabilidade e Índice de Eficiência Produtiva (IEP). Foram também analisados os pesos dos cortes: coxa e sobrecoxa, dorso, peito, asa e coxa da asa. Não foi verificada diferença significativa para as variáveis, peso corporal, ganho de peso, consumo de ração, conversão alimentar, viabilidade, IEP, peso de coxa, peso de
sobrecoxa, peso de dorso, peso de peito e peso de asa e coxa da asa no período de 1 a 42 dias. Com base nos dados obtidos a partir do presente estudo pode-se afirmar que a substituição parcial ou total do milho pelo arroz integral na dieta de
frangos de corte não altera o desempenho e o peso de cortes das aves.
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Produkce a charakterizace proteinových izolátu z různých druhů otrub / Production and characterization of protein isolates from different kinds of branVybíral, Lukáš January 2021 (has links)
This diploma thesis deals with the use of various types of bran as a by-product in the milling of cereals. Mills create a huge amount of this material per year. The most common way of processing bran is mostly incineration and to a lesser extent it is used as feed for livestock. Depending on the type of cereal, bran contains 10-20% of protein, which disappears from the food chain due to combustion. Within the framework of sustainability and valorisation of waste, which has recently been largely discussed, great emphasis is placed on waste minimization whether in the field of its production or further processing. Due to the relatively high protein content, bran appears to be a suitable starting material to produce protein supplements. Proteins can be extracted from bran based on their different solubility at different pH. In the alkaline method, the proteins are first dissolved in an alkaline pH and then precipitated in an acidic medium. Lyophilization is followed by characterization of the extract in terms of yield, protein content, moisture, amino acid profile and digestibility. The highest yield was obtained with the oat bran isolate (13,5 ± 0,6 g of isolate per 100 g of bran). In terms of protein content, the best protein isolate was also obtained from oat bran (95,2 ± 0,4% protein in the isolate). Another determination was the analysis of the amino acid profile, in which a high content of arginine was found in all analyzed protein isolates from bran. Determination of digestibility showed very good digestibility of all produced protein extracts from bran.
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Sledování obsahu vitaminu E ve vzorcích obilovin / Monitoring of vitamin E content in the samples of cerealsCibulcová, Pavla January 2017 (has links)
Thesis deals with the analysis of vitamin E in cereal samples, namely barley and wheat and malt produced from them. Selected samples were treated with low-temperature plasma, fungicide and biological treatment to elimination fungus and mycotoxins. The aim of the thesis was to find out the influence of the treatment, the combination of several types of treatment on vitamin E content in grain and malt. If the content of health-positive substances is not reduced and grain can be used for food, malt, or for feed purposes. The theoretical part focuses on the properties, occurrence, biochemistry and importance of vitamin E for living organisms. It also focuses on the properties of cereals that are a significant source of vitamin E. Malt production and sample treatment are also described. The experimental part describes the field experiment, individual types of treatment, extraction of vitamin E from the samples and determination of vitamin E content by high performance liquid chromatography with fluorescence detection. The results are compared with the current literature. It was found that the treatment did not have a significant negative effect on vitamin E content.
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Plasticité des génomes des pucerons des céréales et de leur plante hôte : recherche in silico et in vitro des éléments transposables des superfamilles Tc1-mariner-IS630 et piggyBac / Plasticity of the genomes of cereal aphids and their host plant : in silico and in vitro analyses of Tc1-mariner-IS630 and piggyBac superfamilies of transposable elementsBouallègue, Maryem 27 March 2017 (has links)
La céréaliculture occupe une place importante dans l’agriculture mondiale et contribue à la sécurité alimentaire des populations. Pour assurer la production des céréales (orge, blé, avoine), il est nécessaire de lutter contre ses ravageurs, essentiellement les pucerons qui sont capables de transmettre plusieurs virus. L’analyse des génomes des pucerons tels que Rhopalosiphum padi, R. maidis, Sitobion avenae, Schizaphis graminum, de leur évolution et de leur relation avec les plantes hôtes (céréales) pourrait contribuer à la mise en place de moyens de lutte pour contrôler les populations de ces ravageurs. Dans ce contexte, cette étude s’est focalisée sur la recherche des éléments transposables des deux superfamilles Tc1-mariner-IS630 et des piggyBac. Les ETs, considérés comme des moteurs de la plasticité génomique et de l’évolution des espèces, sont utilisés en biotechnologie pour développer des outils de transfert de gènes. Dans un premier temps, nous avons recherché des éléments de la famille mariner, ou apparentés à cette famille, dans les génomes séquencés de trois espèces de pucerons : Acyrthosiphon pisum, Myzus persicae et Diuraphis noxia. Sur la base de similitude de séquences, nous avons pu caractériser 183 éléments répartis en trois clades. Le premier, commun aux trois espèces, correspond au clade de la sous-famille irritans DD34D. Il est subdivisé en trois tribus Macrosiphinimar, Batmar-like elements et Dnomar-like elements. Le deuxième comprend l’élément rosa DD41D qui appartient à une famille phylogénétiquement proche de mariner. Le troisième comprend des séquences avec de longues répétitions terminales inversées et inclut deux tribus DD40-41D. Ces deux derniers clades, plus répandus chez A. pisum, dérivent vraisemblablement d’un ancêtre commun et formeraient une nouvelle famille.Dans un deuxième temps, nous avons exploité les résultats de la recherche in silico pour identifier in vitro des éléments de la sous-famille irritans chez les pucerons des céréales et chez leur plante hôte. Deux types d’éléments délétées (MITEs) ont été identifiés chez les pucerons, l’un commun à toutes les espèces avec un pourcentage d’identité supérieur à 98% (Aphidmar) et l’autre spécifique à S. avenae (Samar2). Par ailleurs, les génomes des céréales (orge, blé, brachypodium, égilope) ont été analysés en utilisant comme requêtes des séquences d’éléments de la sous-famille irritans trouvés chez les aphides. Un seul contig de l’orge cultivar barke comprend un élément tronqué de 320 pb, flanqué par de l’ADN génomique de pucerons. La vérification in vitro de la présence de cette séquence chez plusieurs cultivars d’orge révèle deux types de séquences. Le premier est similaire à celui trouvé in silico chez l’orge, le second correspond à l’élément Samar2 délété de 7 nucléotides au niveau du point de cassure de la délétion initiale. Ceci suggère l’existence d’un transfert horizontal entre pucerons des céréales et l’orge. Enfin, l’abondance de données génomiques et la rareté des travaux approfondis portant sur les membres de la superfamille piggyBac, nous ont amenés à analyser in silico leurs caractéristiques, leur distribution et leur évolution. Un total de 117 séquences protéiques de PBLE (éléments autonomes) et de PGBD (éléments domestiqués), ont été utilisées comme requêtes. Quatre groupes structuraux de PBLE ont été définis en fonction de la présence ou absence de répétitions sub-terminales (directes/inversées). Toutefois, il n'existe aucune relation entre ces quatre groupes et la phylogénie des PBLE. Les PGBD soumis à une forte sélection purifiante, sont clairement structurés en neuf groupes dont un correspondant à un nouvel ensemble d’éléments domestiqués trouvé chez les Néopterygiens. L’analyse fine des PGBD révèle que le domaine catalytique de la transposase ancestrale n'est pas toujours conservé. La phylogénie générale des PBLE et des PGBD suggère des événements multiples de domestication des PGBD à partir de différents ancêtres PBLE. / Cereal farming plays an important role in world agriculture and contributes to the food security of the populations. To improve the production of cereals (barley, wheat, oats ...), it is necessary to fight against their pests, especially aphids, able to transmit several viruses. The analysis of aphid’s genomes such as Rhopalosiphum padi, R. maidis, Sitobions avenae and Schizaphis graminum, their evolution and their relationships with their host plants could contribute to define strategies against pest populations. In this context, this work focused on the analysis of transposable elements belonging to Tc1-mariner-IS630 and piggyBac superfamilies. Indeed, TEs are involved in genomic plasticity and evolution of species, and are also used in biotechnology to develop gene transfer tools. In the first chapter, we investigate three available genomes of aphids, namely Acyrthosiphon pisum, Myzus persicae and Diuraphis noxia, to search for elements of the mariner family or close to it. Based on sequence similarities, we were able to characterize 183 elements distributed in three clades. The first one, common to the three species, corresponds to the clade of irritans subfamily DD34D, and is subdivided into three tribes Macrosiphinimar, Batmar-like elements and Dnomar-like elements. The second one includes the rosa element DD41D belonging to a group close to the mariner family. The third one includes sequences with long Terminal Inverted Repeats and is subdivided into two DD40-41D tribes. These two latter clades, more common in A. pisum, likely derive from a common ancestor and would form a new family. In the second chapter, the results of in silico research were exploited, to identify in vitro, elements of the irritans subfamily in cereal aphids and in their host plants as well. Two types of deleted elements (MITEs) have been identified in aphids, one common to all species with a percentage of identity higher than 98% (Aphidmar) and the other one specific to S. avenae (Samar2). In addition, the genomes of cereals (barley, wheat, brachypodium, aegilops) were investigated using as queries sequences of irritans subfamily found in aphids. A single contig identified in Hordeum vulgare (cultivar barke) contains a 320 bp truncated element flanked by genomic DNA of aphids. The presence of this sequence was checked in several barley cultivars by an in vitro approach. Two types of sequences were found. The first one similar to that found in barley from the in silico approach, the second one corresponding to Samar2 element, lacking seven nucleotides at the breaking points of the initial deletion. This suggests a possible horizontal transfer between cereal aphids and barley. In the last chapter, the abundance of genomic data and the scarcity of in-depth research covering all members of the piggyBac superfamily led us to determine in silico their characteristic, their distribution and their evolution. A total of 117 proteic sequences of the PBLE (autonomous elements) and PGBD (domesticated elements) have been used as queries. Four structural groups of PBLE have been identified depending on the presence or absence of sub-terminal repeats (direct / inverted). However, there is no relationship between the structural groups and the phylogeny of these PBLE elements. PGBD are clearly structured into nine main groups including a new group of domesticated elements found in Neopterygii. The catalytic domain of the ancestral transposase is not always preserved, but all these domesticated elements are subjected to a strong purifying selection. The general phylogeny of PBLEs and PGBD suggests multiple and independent domestication events of PGBD from different PBLE ancestors.
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Mapping and restructuring of an Ae. kotschyi derived translocation segment in common wheatHeyns, I.C. 12 1900 (has links)
Thesis (PhD (Genetics))--University of Stellenbosch, 2010. / Includes bibliography. / ENGLISH ABSTRACT: The wild relatives are an important source of new genes for the genetic improvement
of wheat. At Stellenbosch University the leaf and stripe rust resistance genes Lr54 and
Yr37 were transferred from Aegilops kotschyi to chromosome 2DL of wheat. In an
attempt to reduce the size of the whole-arm translocation on which the resistance
genes occur, homoeologous pairing was induced between the wheat and
corresponding Ae. kotschyi chromatin. The purpose of this study was to: (i) Evaluate
the testcross progeny thus obtained; identify translocation recombinants that retained
Lr54/Yr37 and to characterize these using molecular markers (ii) Test for the presence
of genes for photoperiod insensitivity (Ppd) and reduced height (Rht) believed to be
associated with the translocation (iii) Develop a SCAR marker for the most useful
recombinant that could be recovered.
Ten putative translocation recombinants were identified following the
screening of 159 hemizygous testcross F1 plants with three microsatellite markers
specific for chromosome arm 2DL. The recombinants were then characterized with
another five microsatellite markers. Using the eight microsatellite markers the
recombinants were ordered in two size categories with recombinant #74 being the
shortest and having retained only proximal alien chromatin on 2DL. In addition to
microsatellite markers, RAPDs, RGAs, AFLPs and SCAR markers were genetically
mapped to the translocation and further resolved the recombinants into three size
categories. In an attempt to find suitable markers linked to the shortest recombinant
(#74) a polymorphic 410 bp AFLP fragment produced with the enzyme/selective
nucleotide combination EcoRI – AAC/MseI – CAT, was converted into a dominant
SCAR marker. In addition three microsatellite markers that mapped to recombinant
#74 provided a useful recessive molecular marker system to detect Lr54/Yr37.
Evaluation of the 10 recombinants with four 2DS-specific microsatellite markers
revealed a large deletion of this chromosome arm in recombinant #74. This deletion
may affect plant phenotypic characteristics and a strategy to replace the deleted region
in recombinant #74 is proposed. To test for the presence of a gene for photoperiod insensitivity on the translocation,
translocation-carriers plus controls were subjected to long and short day treatments,
and the effect on time to flowering was studied. However, no evidence was found for
the presence of such a gene. A height experiment to test for the presence of an Rht
gene on the translocation confirmed its presence. This gene (designated H) appeared
to be different from Rht8 on chromosome 2DS and was mapped on 2DL. While H
does not occur in a chromosome region that corresponds with the location of Rht8, it
does not rule out the possibility that they could be orthologous loci. Plant height data
obtained for recombinant #74 suggested that H was lost through recombination in this
particular recombinant. A greenhouse experiment suggested that the full-length
translocation increased 100 kernel mass but had a detrimental effect on overall plant
yield. Since a much shorter recombinant (#74) has been obtained, this will also have
to be evaluated for associated effects. Such an evaluation needs to be done under
commercial growing conditions and should involve the comparison of near-isogenic
bulks with and without recombinant chromosome #74.
The stripe rust resistance gene (Yr37) was mapped by screening hemizygous
TF2 progeny of the 10 recombinants with Puccinia striiformis pathotype 6E22A+.
Recombinant #74 retained both Lr54 and Yr37 and the two genes therefore occur
towards the centromere. / AFRIKAANSE OPSOMMING: Wilde verwante spesies is ‘n belangrike bron van nuwe gene vir die genetiese
verbetering van koring. By die Universiteit van Stellenbosch is die blaar-roes en
streep-roes weerstandsgene Lr54 en Yr37 vanaf Aegilops kotschyi na chromosoom
2DL van koring oorgedra. ‘n Poging is vervolgens aangewend om die vol-armtranslokasie
waarop die weerstandsgene voorkom te verklein deur homoeoloë paring
tussen die koring en ooreenstemmende Ae. kotschyi chromatien te induseer. Die
doelstelling van hierdie studie was daarom as volg: (a) Evaluering van die verkreë
toetskruis-nageslag asook die identifisering en karakterisering van translokasie
rekombinante wat Lr54/Yr37 behou het. (b) Toetsing vir fotoperiode onsensitiwiteits-
(Ppd) en verkorte plant-hoogte (Rht) gene wat moontlik op die translokasie kon
voorkom. (c) Die ontwikkeling van ‘n volgorde-spesifieke polimerase kettingreaksie
(PKR) vir die mees bruikbare rekombinant.
Tien translokasie rekombinante is geïdentifiseer nadat 159 hemisigotiese
toetskruis F1-plante met drie mikrosatelliet-merkers, spesifiek vir chromosoom-arm
2DL, ge-evalueer is. Die rekombinante is hierna met vyf verdere mikrosatellietmerkers
getoets. Die data van die agt mikrosatelliet-loci het die rekombinante in twee
grootte-kategorieë geplaas waarvan rekombinant #74 die kortste was met slegs die
proksimale gedeelte van 2DL wat uit vreemde chromatien bestaan. Behalwe
mikrosatellite-merkers is toevallig-geamplifiseerde polimorfiese DNS (RAPD),
weerstandsgeen-analoog (RGA), geamplifiseerde volgordelengte polimorfisme
(AFLP) en volgorde-gekarakteriseerde geamplifiseerde-streke (SCAR) merkers ook
geneties op die translokasie gekarteer. Data van die addisionele merkers het dit
moontlik gemaak om die rekombinante in drie grootte-kategorieë te skei. Pogings om
‘n merker vir die kortse rekombinant (#74) te vind, het gelei tot die omskakeling van
‘n 410 bp polimorfiese AFLP-fragment (geproduseer met die ensiem/selektiewenukleotied
kombinasie EcoRI - AAC/MseI - CAT), na ‘n dominante, volgordespesifieke
PKR-merker. Hierbenewens kan drie mikrosatelliet-merkers wat op
rekombinant #74 karteer as resessiewe merkers vir die identifisering van Lr54/Yr37
gebruik word. Die evaluering van die 10 rekombinante met vier chromosoom 2DSspesifieke
mikrosatelliet-merkers het ‘n groot delesie van chromosoom-arm 2DS in rekombinant #74 uitgewys. Die delesie mag plant fenotipiese kenmerke beïnvloed en
daarom is ‘n strategie vir die vervanging daarvan in rekombinant #74 voorgestel.
Ten einde te toets of ‘n geen vir fotoperiode-onsensitiwiteit op die translokaie
voorkom is translokasie-draers en kontroles aan lang- en kortdag-behandelings
onderwerp en is die effek hiervan op dae-tot-blom gemeet. Geen bewyse vir so ‘n
geen kon gevind word nie. ‘n Hoogte-eksperiment om te toets vir die teenwoordigheid
van ‘n Rht-geen op die translokasie, het bevestig dat so ‘n geen wel voorkom. Die
geen (voorgestelde simbool H) is gekarteer op 2DL en verskil oënskynlik van Rht8 op
chromosoom 2DS. Die verskillende chromosoom-ligging van H en Rht8 skakel egter
nie die moontlikheid dat hulle ortoloë loci mag wees uit nie. Plant-hoogte data vir
rekombinant #74 het daarop gedui dat H nie meer in hierdie rekombinant voorkom
nie. Data van ‘n glashuis-eksperiment het daarop gedui dat die vollengte-translokasie
100-korrel-massa verhoog maar dat dit plant-opbrengs verlaag. Aangesien ‘n
aansienlike korter rekombinant (#74) verkry is, sal dit ook vir gekoppelde effekte
getoets moet word. So ‘n evaluering moet egter onder kommersiële toestande gedoen
word met gebruik van naby isogeniese-lyne met en sonder rekombinante chromosoom
#74.
Die streep-roes weerstandgeen (Yr37) is gekarteer deur hemisigotiese TF2-
nageslag van die 10 rekombinante te toets vir weerstand teen Puccinia striiformis
patotipe 6E22A+. Rekombinant #74 het beide Lr54 en Yr37 behou en die twee gene
karteer dus naby die sentromeer.
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[en] TRACE ELEMENTS DETERMINATION IN FOODS BY SS-GFAAS AND HG AFS / [pt] DETERMINAÇÃO DE ELEMENTOS TRAÇO EM ALIMENTOS POR SS-GFAAS E HG AFSMARIELA NORMA MATOS REYES 31 August 2007 (has links)
[pt] A qualidade de produtos alimentícios tem recebido especial
atenção devido
a sua importância na nutrição e saúde humanas. Neste
sentido, a determinação
de metais traço em alimentos tem se convertido em
importante campo na análise
de alimentos. Em relação aos óleos vegetais, a sua
composição em termos de
metais traço é um critério relevante para a avaliação da
qualidade, uma vez que
se sabe que estes metais afetam a sua taxa de oxidação,
influenciando as suas
características e no seu armazenamento. Por outro lado,
cereais e outros
alimentos de origem vegetal são especialmente relevantes
na alimentação
humana, uma vez que são a base da dieta de muitas
populações do mundo. No
presente trabalho, foi desenvolvido um método analítico
para determinação
direta de Cu e Ni em óleos vegetais por Espectrometria de
Absorção Atômica no
Forno de Grafite (GFAAS): as amostras foram pesadas
diretamente em uma
plataforma de grafite e introduzidas no atomizador, com o
auxílio de um
acessório de amostragem de sólidos. O programa de
temperatura otimizado
permitiu o uso de soluções de calibração aquosas. A
exatidão do procedimento
foi confirmada pela boa concordância entre os resultados
obtidos pelo
procedimento proposto e por procedimentos comparativos. Os
limites de
detecção foram de 0,001 e 0,002 μg g-1 para Cu e Ni,
respectivamente, nas
amostras originais. Em continuação, empregou-se a técnica
de fluorescência
atômica para a determinação do conteúdo total de As, Sb,
Se, Te e Bi em
amostras vegetais, de cereais e legumes, após calcinação
por via seca. Foram
otimizados os parâmetros relativos a geração dos hidretos,
assim como os
parâmetros de fluorescência. Testes de adição de analito,
assim como a análise
de materiais certificados de referência, garantiram a
exatidão do procedimento.
Os resultados encontrados mostraram que as amostras
estudadas encontraramse
todas, nos limites preconizados pela legislação européia.
Finalmente, uma
metodologia analítica não cromatográfica, rápida, sensível
e simples foi
desenvolvida para a quantificação de espécies tóxicas de
arsênio em arroz,
sêmola, acelga e berinjela. Estas espécies foram extraídas
com H3PO4 1 mol L-1
+ Triton XT-114 0,1%, assistida por ultra-som, seguindo-se
a lavagem com
EDTA 0,1% (m/v). As espécies As(III), As(V), DMA e MMA
foram quantificadas no extrato por espectrometria de
fluorescência atômica por geração de hidretos
utilizando um sistema de equações proporcionais, que
correspondem a quatro
condições experimentais diferentes. Os valores de limite
de detecção do método
foram 1,3 (3,15); 0,9 (2,97); 1,5 (0.46) e 0,6 (0,37) ng g-
1 para As(III), As(V), DMA
e MMA, respectivamente, nas amostras de cereais e
vegetais, expressos em
termos do peso seco da amostra. Os estudos da recuperação
mostraram
porcentagens maiores que 90% para as quatro espécies
consideradas. A análise
de especiação de um material de referência de farinha de
arroz certificado para
arsênio total mostrou resultados coerentes e concordantes
com outros estudos
com ele realizados. / [en] The quality of food products has received a special
attention due to its
influence in the human health and nutrition. Thus, trace
metal determination in
foods has turned an important field in food analysis.
Concerning vegetal oils, its
metal trace metal composition is a criterion for the
assessment of their quality
since it is known that these metals affect their rate of
oxidation, influencing its
characteristics and storage management. As part of the
present work the direct
determination of Cu and Ni in vegetal oils by Graphite
Furnace Atomic Absorption
Spectrometry (GFAAS), using the solid sampling strategy
was developed: The
samples were weighed on a graphite platform boat and
inserted in the graphite
tube. An adequate temperature program allowed the
calibration by external
aqueous calibration curves. A good agreement between the
results arisen from
the proposed and two comparative procedures (EPA 3031 and
EPA 3051)
confirmed the accuracy of the proposed procedure. The
limits of detention in the
original samples were 0.002 and 0.001 ìg g-1 for Cu and
Ni, respectively. A
second part of the work has dealt with the determination
of the total content of
As, Sb, Se, Te and Bi in samples of vegetable, cereals and
pulses by HG AFS.
The samples were dry ashed by a proper ashing program, and
the hydride
generation parameters were optimized, as well as those
related to the
fluorescence emission. Recovery testes and the analysis of
certified reference
materials testified the accuracy of the procedure. The
content of the studied
elements in studied samples were all below those of the
European regulation.
Finally, a fast, sensitive and simple non chromatographic
methodology was
developed for the speciation analysis of toxic arsenic
species in rice, wheat
semolina, chard and aubergines samples. Ultrasound
assisted extraction of the
toxic arsenic species was carried with 1 mol of L-1 H3PO4
and 0.1% (m/v) Triton
XT-114. After the extraction, As(III), As(V), DMA and MMA
were quantified by
hydride generation atomic fluorescence spectrometry at
four different
experimental conditions. The fluorescence intensities
derived from these four
measurements were introduced in a system of four
proportional equations,
permitting the calculation of the individual species
concentration.. The detection
limits were 1.3 (3.2), 0.9 (3.0), 1.5 (0.5)) and 0.6 (0,5)
ng g-1 for As(III), As(V), DMA and MMA, respectively in
the cereals and (vegetable) samples, expressed
in terms of the dry weight. Recoveries greater than 90%
for the four considered
species in samples spiked at 100 ng g-1 level were
obtained as well as the
assurance of no species interconversion. The speciation
analysis of a rice flour
reference material certified for total arsenic led to
coherent results, which were
also in agreement with other speciation studies made on
the same CRM.
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Bioativador em culturas monocotiledôneas: avaliações bioquímicas, fisiológicas e da produção / Bioactivator in monocot crops: biochemical, physiological and production analysisMacedo, Willian Rodrigues 18 February 2013 (has links)
Estudos sobre agroquímico geralmente reportam sobre sua eficiência no controle de pragas. Como no caso do tiametoxam, um inseticida sistêmico do grupo dos neonicotinóides que atua inibindo a ação do receptor nicotínico acetilcolina (nAChR) dos insetos levando-os à morte. Porém, essa molécula apresenta ações fisiológicas nas plantas capazes de influenciar o desenvolvimento das culturas, e quando um agroquímico apresenta essa atividade é comumente chamado de bioativador, devido ao aumento do vigor e da produtividade das plantas tratadas. O objetivo deste trabalho foi avaliar os efeitos bioquímicos, fisiológicos e produtivos de doses crescentes do tiametoxam, aplicado via tratamento de sementes, nos cultivos de trigo, braquiária, arroz e milho. Experimentos com trigo, braquiária e arroz foram conduzidos em vasos, sob casade- vegetação, no Horto Experimental do Departamento de Ciências Biológicas da ESALQ/USP, Piracicaba, SP. Enquanto a condução da cultura do milho ocorreu em casa-de-vegetação, do Departamento de Agronomia no CEDETEG/UNICENTRO, e em área de plantio comercial, ambos no município de Guarapuava, PR. Durante a realização dos experimentos foram mensuradas características biométricas de: índice de emergência; altura de plantas; índice de clorofilas (SPAD); massa seca da parte aérea; comprimento, área e volume radicular. Parâmetros bioquímicos como: atividade de nitrato redutase; fenilalanina amônia-liase; conteúdo de proteína total; pigmentos fotossintéticos e conteúdo de nutrientes foliares. Parâmetros sobre a qualidade nutricional da braquiária também foram analisadas. E ao final do ciclo reprodutivo dos cereais foram determinados alguns parâmetros relacionados à produção. Foi constatado que o tiametoxam interferiu sobre diversos parâmetros bioquímicos, em todas as culturas testadas, com destaque para a potencial ação dessa molécula sobre atividades de nitrato redutase e fenilalanina amônia-liase, bem como sobre o conteúdo de proteína total em trigo e braquiária, além de alterar o teor de pigmentos fotossintéticos foliares em arroz e milho. Para as culturas do trigo e da braquiária foram notadas modificações severas sobre a fisiologia e produção. Concluiu-se que a aplicação de tiametoxam, via tratamento de sementes, foi responsável por moderar o metabolismo e o desenvolvimento vegetal, até o final do ciclo da planta, de maneira que as plantas submetidas a essa molécula expressaram maior vigor e, consequentemente, apresentaram maior aptidão para incrementar sua produção. / Studies on agrochemicals generally report on their effectiveness in pests control. As with thiamethoxam, a systemic insecticide of the neonicotinoid group that acts by inhibiting the action of acetylcholine nicotinic receptor (nAChR) of insects, leading to death. But this molecule which has physiological effect in plants, can influence crop development; and when an agrochemical presents this activity, it is commonly called bioactivator due to increased vigor and productivity of the treated plants. The aim of this study was to evaluate: biochemical, physiological and productive effects of increasing doses of thiamethoxam applied as seed treatment in wheat, Brachiaria, rice and corn crops. Experiments with wheat, rice and Brachiaria were conducted in pots under greenhouse, in the Horto Experimental of Biological Sciences Department of ESALQ/USP, Piracicaba, SP. While one corn crop was conducted in a greenhouse of the Department of Agronomy at CEDETEG / UNICENTRO, the other one was conducted in the field, both in Guarapuava, PR. We measure the biometric characteristics: emergence index, plant height, chlorophyll index (SPAD), shoot dry weight, length, root area and volume. Biochemical parameters such as: nitrate reductase activity, phenylalanine ammonia-lyase, total protein content, photosynthetic pigments and leaf nutrient content. Parameters on the nutritional quality of Brachiaria were also analyzed. And at the end of the reproductive cycle of cereals some parameters related to production were determined. It was found that thiamethoxam interfered in various biochemical parameters in all tested crops, highlighting the potential action of this molecule on activities of nitrate reductase and phenylalanine ammonia-lyase, as well as the total protein content in wheat and pasture, besides changing the content of photosynthetic pigments in rice and corn leaves. For wheat and Brachiaria crops severe changes were noted on the plant physiology and production. It is concluded that the application of thiamethoxam, via seed treatment, was responsible for moderating metabolism and plant development, until the end of the life cycle of the plant, so that the plants under this molecule expressed greater vigor and thus had higher ability to increase production.
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Ação de reguladores vegetais em trigo (Triticum aestivum L.) e cevada (Hordeum vulgare L.) / Effect of plant growth regulators in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.)Murcia, Julian Alejandro Giraldo 14 July 2016 (has links)
Os vegetais possuem metabólitos endógenos circulantes nos tecidos, que não necessariamente possuem função nutricional, mas atuam na regulação do crescimento e do desenvolvimento, os hormônios vegetais. Estes, quando utilizados exogenamente, permitem ações planejadas no crescimento das plantas. Igualmente, análogos sintéticos com ação semelhante vêm sendo utilizados na agricultura com o mesmo objetivo. No entanto, o efeito destes reguladores vegetais é variável entre as espécies e em suas fases fenológicas, com necessidade de estudos especificos que propiciem respostas adequadas aos objetivos de sua aplicação. Da mesma forma, encontramos também moléculas capazes de atuar na produção endógena de hormônios, limitando ou induzindo sua produção, afetando os processos de crescimento e desenvolvimento vegetal. A aplicação de tais substâncias na agricultura pode ser benéfica no controle do crescimento vegetal, revertendo a energia produzida pela fotossíntese para a produção dos cultivos. Diversos cultivos, incluindo os de cereais, tendem à um crescimento vegetativo exagerado com o incremento do uso de fertilizantes, causando quedas de produtividade e problemas na colheita devido ao acamamento das plantas. Diante disso, o presente estudo tem como objetivo avaliar as alterações morfológicas e fisiológicas do uso de reguladores vegetais na cultura do trigo (Triticum aestivum L.) e da cevada (Hordeum vulgare L.), visando redução do porte das plantas sem alterações ou com incremento de produção. Os experimentos foram desenvolvidos com ambas espécies de cereais, semeadas em vasos. As aplicações dos tratamentos foram realizadas no início da fase de alongamento do colmo. Nos experimentos, foram avaliados os efeitos da pulverização foliar de diferentes reguladores vegetais que restringem a síntese de giberelina na planta: ácido abscísico (ABA), etil trinexpac (Moddus), daminozide (SADH), ethephon (Ethrel) e cloreto de clormequat (CCC). Foram avaliadas variáveis relacionadas ao retardamento do crescimento vegetativo e à produção de carboidratos, assim como a produção das plantas tratadas, tais como: altura das plantas, índice SPAD, transpiração, condutância estomática e massa seca do caule e espigas. Os dados obtidos foram submetidos à análise de variância e quando significativos, os tratamentos foram comparados pelo teste de Tukey ao nível de 5% de probabilidade. A pulverização de ABA, SADH e Ethrel diminuiu significativamente a massa seca do colmo e promoveu retardamento do crescimento, no entanto, a aplicação de ABA aumentou significativamente o índice de colheita, assim como a massa seca dos grãos. Tratamentos com duas pulverizações de ABA 24 g L-1, com uma semana de intervalo restringiu o alongamento da planta, melhorando a arquitetura da mesma, o teor de clorofila e as trocas gasosas, nas culturas de trigo e cevada, estimulando incremento de 23% na massa seca dos grãos de trigo e de 33% em cevada; assim sendo, a aplicação deste retardante de crescimento pode ser considerada para ser utilizada em lavouras de cereais. / Plant tissues contain circulating endogenous metabolites which not necessarily play nutritional function but can regulate growth, plant hormones, that can be also exogenously applied for planned effects in plant growth. These molecules when sprayed on plants allow desirable effects on the plant growth. Moreover, synthetic analogues with similar action have been used in agriculture for the same purpose. However, the effect of growth regulators is variable among species and their phoenological stages, requiring specific studies that provide appropriate responses to their application. Similarly, there are also capable of acting on endogenous hormone production, limiting or stimulating their biosynthesis and consequently affecting the processes of growth and plant development. The application of such molecules in agriculture can be beneficial in controlling the plant growth, reversing the energy produced by photosynthesis for that growth to agronomic yield of crops. Several crops, including cereals, tend to respond with excessive vegetative growth to the increase of fertilizer application causing productivity decreases and damages to the crop due to the plant lodging. Thus, the present study was carried out to evaluate the morphological and physiological changes by the use of plant growth regulators on wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.), aiming the reduction of the plant size and increases of productivity. The experiments were conducted with both cereal species sown in pots. The applications of the treatments were performed at the beginning of stem elongation stage The effects of foliar application of different plant growth regulators that restrict the gibberellin synthesis in the plant were evaluated: Abscisic acid (ABA), trinexapac-ethyl (Moddus), Daminozide (SADH), Ethephon (Ethrel), and chlormequat chloride (CCC). The following variables were measured: plant height, SPAD index (indirect chlorophyll content), transpiration, stomatal conductance, and dry mass of stems and spikelets. The data were analyzed by the Tukey test at 5% probability level. The spray with ABA, SADH, and Ethrel decreased significantly the dry mass of the stem and promoted growth retardation (plant height). However, the application of ABA increased significantly the harvest index, as well as the dry mass of the grains. Treatments with two sprays of ABA (24 g L-1), with an interval of a week restricted the plant growth in height improving the architecture thereof, chlorophyll content, and gas exchange, resulting in an increment of 23% and 33% in dry matter of grains of wheat and barley, respectively. Therefore, the application of ABA may be considered as an alternative for improving the productivity of cereal crops.
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Estudo da via do ácido aspártico descrevendo uma variedade de técnicas de engenharia genética e bioquímicas / The study of aspartate metabolic pathway: a description of various biochemical and genetic engineering techniquesNazareno, Amerivan Cirqueira 18 June 2013 (has links)
Esta pesquisa bibliográfica teve o propósito de elucidar a via do acido aspártico, apontando como fonte deste estudo os cereais. O objetivo principal desta pesquisa consistiu em estudar a via do acido aspártico, visando descrever uma variedade de técnicas de engenharia genética e bioquímicas que podem ser empregadas para aumentar a qualidade nutricional de cereais, podendo, assim, compreender o que acarreta o aumento do acumulo de lisina, metionina e treonina nos grãos para suprir essa necessidade na formação de uma proteína balanceada nutricionalmente. Foi realizada uma busca exaustiva em bases de dados Google Scholar, Portal Capes, ISI web of Science, no período de publicação de 1970 a 2012. Foram adotados textos de referencia internacional e nacional. Esta pesquisa foi dividida em três etapas: via do acido aspártico e seus aminoácidos derivados em plantas superiores de 1970 a 1997, via metabólica do acido aspártico no período de 1997 a 2006 e estratégias interessantes para aumentar o nível dos aminoácidos essenciais da via do acido aspártico em plantas no período de 2006 ate o momento. A primeira etapa foi desenvolvida relatando o acido aspártico como precursor dos aminoácidos essenciais: metionina, lisina, treonina e isoleucina. Entre os essenciais, a lisina e um dos mais estudados devido a escassez em muitos cereais, o que contribuiu para o estudo extensivo da via do acido aspártico, revelando, assim, a importância da aspartato quinase (AK), homoserina desidrogenase (HSDH) e dihidrodipicolinato sintase (DHDPS) como enzimas chaves para a regulação da síntese de lisina. A aspartato quinase (AK) exerce um controle sobre via do acido aspártico. A enzima dihidrodipicolinato sintase (DHDPS) regula a síntese de lisina. Na segunda etapa foi apresentada a importância dos aminoácidos sintetizados nas plantas através de complexas vias metabólicas que são controladas por enzimas, intermediários, substratos e aminoácidos. Este estudo também relata os aspectos importantes para uma melhor compreensão da síntese e o acumulo de aminoácidos solúveis e incorporados em proteínas. A terceira etapa foi apresentar estratégias interessantes para utilização em estudos, visando aumentar o nível de aminoácidos essenciais através da manipulação de genes já existentes, como também a introdução de genes estranhos nas plantas. Devido a importância nutricional, essa via tem sido extensivamente estudada, utilizando técnicas de engenharia genética e bioquímica. Pesquisadores tem apresentado esforços considerados no estudo desta via a fim de contribuir para futuras manipulações genéticas, cujo objetivo e produzir plantas com alto conteúdo de lisina, metionina e treonina. / The aim of this research was to elucidate the aspartate metabolic pathway using grains of cereal as a source of study. Therefore, it was necessary to understand the aspartate metabolic pathway in order to depict various biochemical and genetic techniques which can be used to enhance the nutritional value in cereals. After studying theses issues, it was possible to understand the results of having cereals with a high lysine, methionine, and threonine content, so that grains can have balanced protein content. For that reason, an exhaustive research was done by using international and national scientific data published in 1970 to 2012. These data were found in Google Scholar, Portal Capes, and ISI Web of Science. This research was divided in three parts: studies of aspartate metabolic pathway and their essential amino acids derived from plants published in 1970 to 1997, studies of aspartate metabolic pathway published in the period of 1997 to 2006, and interesting strategies to enhance the level of essential amino acids of the aspartate metabolic pathway in plants from 2006 to this moment. Firstly, this investigation reported about the aspartic acid as a precursor of essential amino acids such as methionine, lysine, threonine, and isoleucyne. Among the essential amino acids, lysine has been the most researched due to its lack in many kinds of grains. Needless to say, it has contributed to the intensive study showing the relevancy of aspartate kinase (AK), homoserine dehydrogenase (HSDH), dihydrodipicolinate synthase (DHDPS), as key enzymes for lysine regulation. The aspartate kinase (AK) has an important role on the aspartate metabolic pathway, meanwhile the dihydrodipicolinate synthase (DHDPS) is intrinsically involved on lysine synthesis regulation. Secondly, this investigation presented the importance of the amino acids which are synthesized by plants through metabolic pathways that are controlled by enzymes, intermediates, substrates, and amino acids. In addition, this research reported relevant aspects whereby scientists can improve their understanding about the synthesis and accumulation of soluble amino acids which are incorporated in proteins. Finally, the third part showed interesting strategies which can be used in future researches in order to increase not only the level of essential amino acids by manipulating genes, but also the introduction of odd genes in plants. Given the nutritional relevancy, this pathway has been extensively investigated by using techniques used by biochemical and genetic engineering. Hence, researchers have demonstrated a considerable effort on this matter contributing for future genetic manipulations, so that plants with high lysine, methionine, and threonine content can be produced.
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Acurácia de mapas altimétricos obtidos com DGPS na colheita de cereais. / Accuracy of elevation maps generated with dgps with on yield monitors.Cremonini, Luiz Claudio Moreira 05 February 2003 (has links)
A produção agrícola passa por grandes transformações perante um= mercado sempre mais competitivo e com consumidores mais exigentes, tendo que se obter maiores produtividades com menor uso de insumos e defensivos agrícolas. Diante deste cenário, novas formas de gerenciamento agrícola se fazem necessárias e com técnicas de Agricultura de Precisão se torna possível compreender e intervir em algumas variáveis de produção agrícola. Na região centro-sul brasileira uma das características marcantes é a topografia nem sempre favorável à agricultura mecanizada. O relevo, por sua vez, pode influenciar vários fatores de produção como gênese, textura, retenção de água e teores de nutrientes do solo, severidade de doença, entre outros. No mapeamento da produtividade, etapa essencial na obtenção de informações para se implementar o ciclo de Agricultura de Precisão, são coletadas diversas informações, entre elas a altitude dos pontos amostrados no terreno. Este trabalho teve como objetivo avaliar a acurácia de mapas altimétricos obtidos por receptores de GPS. A execução se deu em três etapas, a primeira avaliando a acurácia de posicionamento vertical de dois receptores de GPS, um com correção de sinal por pós-processamento e outro através de sinal via satélite em tempo real. A segunda etapa avaliou a acurácia de mapas altimétricos gerados com dados de simulações de colheitas de cereais, comparando-os com levantamento realizado por método convencional e a terceira etapa avaliou a acurácia de mapas altimétricos obtidos por sistema comercial de monitoramento de produção obtido em duas colheitas seguidas nessa mesma área. A correção pós-processada do sinal de GPS se mostrou mais acurada que a correção via satélite e os mapas altimétricos obtidos nas simulações de colheita e nas colheitas reais oferecem qualidade mínima necessária para a obtenção de informação de altimetria, para regiões de relevo mais acidentado, porém não aplicável para regiões com relevos planos. A junção dos dados de diferentes passadas, tanto nas simulações quanto nas colheitas reais melhorou a qualidade da informação de altimetria obtida com DGPS. / A agricultural has been exposed to strong transformations, with a market always more competitive and with more exigent consumers and farmers having to obtain larger yields with less use of agricultural defensives. With this scenery, new forms of agricultural management are necessary and the use of precision agriculture techniques, is a possibility on trying to understand and interfere on production factors. In the southern Brazilian region the rough topography, is an important caracteristic not always favorable to mechanized agriculture. Topography can correlated with production factors, like genesis, texture, water and nutrients content in the soil, severity of diseases, among others. In the yield mapping process, first step of precision agriculture, altitude data is collected together with several other data. This work aims to evaluate the accuracy of elevation maps generated with GPS receivers. It was conducted on three stages. First, the accuracy of vertical position was evalauted on two GPS receivers, one with differential correction on post processing and other with real time differential correction by satelite. The second stage, evaluated the accuracy of elevation maps generated by simulation of harvesting operation and the third stage evaluated the accuracy of elevation maps generated with datas from a commercial yield mapping system generated on two harvesting seasons on the same area. The post processing differential correction showed to be more acurate than the real time differential correction. The elevation maps generated with simulated and real harvesting operations offered a minimum quality for altitude data, for regions with uneven surface but not for flat regions. Joining altitude data from different simulations on consecutive real harvesting operation improved the quality of altitude information obtained with DGPS.
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