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Memoria para optar al Título Profesional de Ingeniero Agrónomo / En Chile se ha observado problemas de establecimiento y rendimiento de lupino cuando se cultiva después de trigo en condiciones de cero labranza con rastrojos sobre el suelo. Esta inhibición ha sido descrita como efecto alelopático del rastrojo de trigo sobre lupino. Dado que en el país se cultivan dos especies de lupino (L. albus y L. angustifolius) y que el efecto del rastrojo sobre lupino puede ser modificado por las condiciones ambientales, es que los objetivos de este trabajo fueron determinar la sensibilidad intra e interespecífica de dos especies de lupino al extracto de rastrojo de trigo y determinar la capacidad alelopática del residuo de trigo sometido a diferente grado de descomposición. Se realizaron dos ensayos. El primer ensayo fue para determinar la sensibilidad intra e interespecífico de las dos especies de lupino al extracto de rastrojo de trigo y el segundo ensayo fue para evaluar la capacidad alelopática del residuo de trigo sometido a diferente grado de descomposición. Para el primer ensayo se embebió semillas de siete genotipos de Lupinus albus y nueve genotipos de Lupinus angustifolius con extracto de 0, 23, 47 y 70 g de rastrojo de trigo L-1. Se evaluó la capacidad germinativa (CG), valor máximo de germinación (VM), longitud de radícula e hipocotilo (LR y LH), peso fresco de radícula e hipocotilo (PR y PH), relación LR/LH y longitud de plántula (LP). Para el segundo ensayo se dejó 0, 5 y 10 Mg ha-1 de rastrojo sobre la superficie de un suelo que había tenido trigo la temporada anterior. Estas cantidades de rastrojo fueron sometidas a distintos grados de descomposición aplicando tres niveles hídricos mediante una línea de aspersión. Se evaluó la descomposición del rastrojo y su capacidad alelopática. Se encontraron diferencias entre especies. Lupinus angustifolius mostró una mayor sensibilidad al extracto de rastrojo, observándose reducción en el valor máximo de germinación. Esta variable permitió encontrar diferencias inter e intraespecíficas. Las diferencias intraespecíficas en L. albus fueron consecuencia de las diferencias entre genotipos, mientras que las diferencias entre los genotipos de L. angustifolius se debieron a la interacción genotipo * concentración de extracto, por lo que la selección de genotipos tolerantes al extracto de rastrojos debe ser distinta según la especie de lupino. La aplicación de riego, independiente de la cantidad, aumentó la descomposición del rastrojo, mientras que el establecimiento de lupino aumentó con la mayor cantidad de agua aplicada en el periodo de mayor temperatura. El efecto de la cantidad de rastrojo superficial en el establecimiento de lupino fue secundario. Se evidenció un importante efecto alelopático en el suelo que sólo tenía raíces de trigo de la temporada anterior. El bioensayo con extractos acuosos de rastrojo de trigo afectó la germinación de lupino, pero no identificó diferencias alelopáticas entre los residuos con distinto grado de descomposición. / Problems of lupine establishment and yield have been observed in Chile when this crop is grown following wheat under zero tillage conditions with stubble on the ground. This inhibition has been described as an allelopathic effect of wheat stubble on lupine. Since two species of lupine (L. albus and L. angustifolius) are grown in the country and the effect of stubble on lupine may be modified by environmental conditions, the objectives of this study were to determine the intra- and inter-sensitivity of these lupine species to wheat stubble extract and to determine the allelopathic capacity of wheat residue subjected to varying degrees of decomposition. Two tests were carried out for this purpose. The first one was to determine the intra-and interspecific sensitivity of the two lupine species to wheat stubble extract and the second one was to evaluate the allelopathic capacity of wheat residue subjected to varying degrees of decomposition. For the first trial seeds of seven genotypes of Lupinus albus and nine genotypes of Lupinus angustifolius were imbibed in 0, 23, 47 and 70g of wheat stubble extract L-1. Germinative capacity (CG), maximum germination (VM), radicle and hypocotyl length (RL and HL), fresh weight of radicle and hypocotyl (PR and PH), RL/HL ratio and seedling length (LP) were evaluated. For the second test, 0, 5 and 10 mg ha-1 of stubble were left on the soil surface which had had wheat the previous season. These amounts of stubble were subjected to different degrees of decomposition using three water levels through a spraying line. Stubble decomposition and its allelopathic capacity were evaluated. Differences were found between species. Lupinus angustifolius showed a greater sensitivity to stubble extract, with a decrease in the maximum germination value being observed. This variable allowed to find inter- and intraspecific differences. The instraspecific differences in L. albus resulted from the differences among genotypes, while differences among L. angustifolius genotypes were due to the genotype-extract interaction, for which reason the selection of genotypes tolerant to stubble extract must be different depending on the lupine species. Irrigation application, irrespective of its amount, increased stubble decomposition, whereas lupine establishment increased with the greatest amount of water applied at the time of highest temperature. The effect of surface stubble amount on lupine establishment was secondary. An important allelopathic effect was seen on the soil which only exhibited roots from the previous season’s wheat. The bioassay with aqueous extracts of wheat stubble affected lupine germination, but did not identify allelopathic differences among residues with different levels of decomposition.

Submitted by Eunice Novais (enovais@uepg.br) on 2018-07-05T17:43:12Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Adlliz Salgado.pdf: 1207262 bytes, checksum: 92b81817140d534259d580cdd9c338ff (MD5) / Made available in DSpace on 2018-07-05T17:43:12Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Adlliz Salgado.pdf: 1207262 bytes, checksum: 92b81817140d534259d580cdd9c338ff (MD5) Previous issue date: 2017-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O P é o nutriente que mais limita a produtividade agrícola no Brasil, devido ao material de origem dos solos brasileiros, pela forte interação do P com o solo e pela sua precipitação com compostos de Fe, Al e Ca, por esse motivo os adubos fosfatados tem sido utilizado em maiores quantidades comprometendo as reservas mundiais que vem diminuindo. Com isso, há necessidade de se aprimorar a eficiência do uso de P na agricultura e o uso de gesso pode ser uma alternativa, devido à presença em sua composição de P e ao favorecimento do crescimento radicular. Sendo assim o objetivo deste trabalho foi avaliar o efeito residual da aplicação de gesso na eficiência da adubação fosfatada para a sucessão trigo-soja em sistema plantio direto. O experimento foi instalado em outubro de 2013, no município de Ponta Grossa, em um Latossolo Vermelho distrófico típico, textura argilosa. O delineamento experimental empregado foi o de blocos ao acaso, em parcelas subdivididas, com três repetições. Nas parcelas (180 m2) foram aplicadas, no sulco de semeadura, nas safras de inverno e verão, quatro doses de P (0, 30, 60 e 90 kg P2O5 ha-1) na forma de superfosfato triplo (SFT) e, nas subparcelas (45 m2) foram empregadas quatro doses de gesso agrícola (0, 2, 4, 6 t ha-1), em outubro de 2013. A sucessão de culturas do experimento foi: trigo (2015) e soja (2015/2016), sendo avaliado o efeito residual de gesso agrícola após 33 meses de sua aplicação (outubro de 2013) e os efeitos das doses de P. As avaliações realizadas foram os atributos químicos do solo (pH, Al3+, Ca2+, Mg2+, K+, S-SO42- e P) nas camadas (0-10, 10-20, 20-40 e 40-60 cm de profundidade), e nas culturas do trigo (2015) e soja (2015/2016) foram avaliados: (diagnose foliar, extração, rendimento de grãos e o fator parcial de produtividade). O efeito residual de gesso agrícola na superfície e a adubação fosfatada no sulco de semeadura ocasionaram melhoria nos atributos químicos do solo, sendo que o incremento das doses de P ocasionaram aumento de P (0-20 cm), SO42- (20-40 cm), Ca2+ e K+ (40-60 cm) e diminuição de P (20-40 cm), SO42- (0-10 cm) e Mg2+ (40-60 cm). O efeito residual do gesso agrícola ocasionou aumento de Ca2+ (0-60 cm), P (0-20 cm), SO42- (10-60 cm) e K+ (40-60 cm), e diminuição de Al3+ (10-20 cm). Na cultura do trigo, o incremento das doses de P aumentaram o teor foliar de P, Ca e S e diminuiu a extração de Fe, já com o incremento de gesso ocorreu aumento do teor foliar de Ca e S e diminuição do teor de Mg, e aumento da extração de P, S e Cu. Na cultura da soja o incremento das doses de P e de gesso não ocasionaram diferenças estatísticas na diagnose da cultura, já para a extração da planta, houve aumento da extração de K, Fe, Mn e Zn com o incremento das doses de P, e aumento na extração de P, Ca, S e Fe com o incremento das doses de gesso. Para o rendimento de grãos o aumento das doses de P não foram eficientes para aumentar a produtividade das culturas de trigo e soja, já o incremento das doses de gesso foi eficiente somente para a cultura do trigo aumentando em 21,8% o rendimento de grãos. O incremento nas doses de P aplicadas aumentou o fator parcial de produtividade de P (FPPP) nas culturas de trigo e soja, quando a menor dose de P (30 kg ha-1) foi aplicada. O efeito residual do gesso no aumento da produtividade de trigo não foi ocasionado por melhoria na eficiência de utilização de P pelas plantas. / P is the nutrient, which most limits agricultural productivity in Brazil, due to the material from Brazilian soils, because of the strong interaction of P with soil, and its precipitation with compounds Fe, Al and Ca, for this reason, phosphate fertilization has been utilized in larger quantities, compromising world supplies, which have been diminishing. Therefore, it is necessary to improve the efficiency of the utilization of P in agriculture, and the utilization of gypsum may be an alternative, due to the presence of P in its composition and the favoring of root growth. Thus, this paper is aimed at evaluating residual effect of gypsum application in the efficiency of phosphate fertilization for the succession wheat-soybean in no tillage system. The experiment was installed in October 2013, in the municipality of Ponta Grossa, in a typical dystrophic Red Latosol, clay texture. The experimental delineation applied was the blocks by chance, in subdivided parcels, with three repetitions. In the (180 m2) parcels, four doses of P (0, 30, 60 and 90 kg P2O5 ha-1) were applied, in-furrow, for winter and summer harvests, in the form of Triple SuperPhosphate (TSP) and, in the (45 m2) subparcels, four doses of agricultural gypsum were applied (0, 2, 4, 6 t ha-1), in October of 2013. The succession of crops for the experiment was: wheat (2015) and soybean (2015/2016), residual effect of agricultural gypsum was evaluated 33 months after its application (October of 2013), along with the effects of P doses. The evaluations performed were about the chemical attributes of the soil (pH, Al3+, Ca2+, Mg2+, K+, S-SO42- and P) in layers (0-10, 10-20, 20-40 and 40-60 cm deep) in wheat crops (2015), and in soybean crops (2015/2016); foliar diagnosis, extraction, grain yield, and the partial factor productivity were evaluated. The residual effect of agricultural gypsum in the surface and phosphate fertilization in-furrow caused improvements to the chemical attributes of the soil, where the addition of P doses caused an increase of P (0-20 cm), SO42- (20-40 cm), Ca2+ and K+ (40-60 cm) and a decrease of P (20-40 cm), SO42- (0-10 cm) and Mg2+ (40-60 cm). The residual effect of agricultural gypsum caused an increase of Ca2+ (0-60 cm), P (0-20 cm), SO42- (10-60 cm) and K+ (40-60 cm), and a decrease of Al3+ (10-20 cm). In wheat crops, the addition of P doses increased the foliar content of P, Ca and S, and decreased the extraction of Fe, on the other hand with the addition of gypsum an increase of Ca and S foliar content occurred and a decrease of Mg content, and an increase of P, S and Cu extraction. In soybean crops, the addition of P doses and gypsum caused statistical differences in the crop diagnosis, and then again, for the extraction of the plant, there was an increase of K, Fe, Mn and Zn extraction with the addition of P doses, and an increase of P, Ca, S and Fe extraction with the addition of gypsum doses. For grain yield, the increase of P doses were not efficient to boost productivity in wheat and soybean crops, as for the addition of gypsum doses, it was only efficient for wheat crops with a 21,8% increase of grain yield. The addition in applied P doses increased the partial factor productivity (PFP) of P in wheat and soybean crops, when the lowest dose of P (30 kg ha-1) was applied. The residual effect of gypsum in the increase of wheat productivity did not happen because of improvements in the efficiency of P usage by plants.

Triticum aestivum (bread wheat) is an important cereal crop not only in Canada but also worldwide. The pathogen Fusarium graminearum is responsible for causing the disease fusarium head blight and generates yield loses and mycotoxin contaminated grains, including in wheat. A strategy used to mitigate this problem is through the production of FHB resistant wheat varieties by crossing strongly resistant germplasms from closely related wheat species. Thinopyrum elongatum is a wild wheat grass that carries genetic resistance to FHB on the long arm of its chromosome 7E (7EL). Previous work has developed genetic material by crossing Chinese Spring (CS) ph1b line with a CS-7E(7D) substitution line to facilitate introgression of 7E fragments from Thinopyrum into the 7D chromosome of wheat. In the first part of this project a genetic order for previously designed 7EL- and 7D- specific markers was proposed using IWGSC RefSeq v1.0 and was used to characterize the introgressed material from the above cross. Progeny from BC1F7 and BC1F5 families of different lineages were genotyped and phenotyped to characterize regions of introgression which were estimated to be at least 42 and 22 Mbp respectively. Gene expression analysis was also performed for selected 7EL genes. Results showed that the expression of selected 7EL genes present within the introgressed fragments were highly variable between the three families characterized as well as within families. It was also observed that the 7EL introgressed progeny had variable expression when compared to the addition line CS-7EL. Additionally gene expression analyses were also performed using 7D genes. These results showed that there was variation in 7D gene expression between the 7EL introgressed progeny and the controls CS-Fg and addition line CS-7EL-Fg. Possible explanations regarding the variation in gene expression includes differential methylation patterns, silencing of genes in the progeny, alteration of repetitive sequences or activation of transposable elements. Further research will be needed to test these hypotheses.

Wheat (Triticum aestivum L.) grown in controlled environments with a 24-hour photoperiod was analyzed for phenylpropanoid and amino acid metabolites. Discrete spectral environments, including a metal halide, high-pressure sodium and low-pressure sodium lamps, provided both photosynthetically active radiation and phenylpropanoid inducing fluences of light . A greenhouse spectral environment supplemented with fluorescent lamps was also used to culture wheat . All. four spectral envi ronments were used to culture wheat to maturity separately. The activities of phenylalanine and tyrosine ammonia-lyase were photoinduced in wheat tissue obtained from plants grown in the metal halide, high -pressure sodium and greenhouse spectral environments. These enzyme activities are the committed catalytic step in phenylpropanoid biosynthesis and were induced in wheat tissue by fluences of light in the ultraviolet and blue regions of the spectrum. The low-pressure sodium lamp , which does not provide strong irradiance in these wavelengths , produced significantly lower ammonia-lyase activities than were observed in wheat grown within the metal halide , high-pressure sodium, or greenhouse spectral environments. These effects were not caused by phytochrome, since calculation of PfrfPtotal for the low-pressure sodium lamp was higher than the ratio obtained from metal halide or high-pressure sodium lamps. Lignin was also significantly reduced in wheat grown with low-pressure sodium lamps . Several essentialamino acids were in lower molar concentration in protein from wheat grown under low-pressure sodium lamps. However, phenylalanine and tyrosine were in significantly higher concentration in wheat grain produced in this spectral environment, and amino acid concentrations of wheat cultured with the low-pressure sodium lamp are regarded as a direct result of the spectral properties of this light source.

Doctor of Philosophy / In this thesis, a set of wheat varieties (Triticum aestivum L.) produced by the Value Added Wheat Cooperative Research Centre with lower swelling power as compared to commercial Australian wheat varieties were studied to enhance our understanding of the role of amylose in starch functionality. These starches originated from a heterogeneous genetic background and had a narrow range of elevated amylose content (35 to 43%) linked with diverse functional properties. Small-angle X-ray scattering together with complementary techniques of differential scanning calorimetry and X-ray diffraction have been employed to investigate the features of starch granular structure at the nanometer scale. Starch chemical structure was characterized in terms of amylose content and amylopectin chain length distribution. Starch functionality was studied by a series of swelling, pasting and enzymic digestion methods. This study showed that swelling power of flour is a simple test that reflects a number of industrially relevant characteristics of starch, and therefore can be used as an indicator of amylose content and pasting properties of starch. In contrast to waxy starches and starches with normal amylose content, wheat starches with increased amylose content displayed characteristic pasting properties that featured decreasing peak, breakdown and final viscosities with increasing amylose contents. Existence of a threshold value in amylose content, above which final viscosity of starch paste does not further increase with increasing amylose content, was proposed. Variability in amylopectin chain length distribution was shown to have an additional effect on the swelling and pasting properties of the starches. On the molecular level, increased amylose content was correlated with increased repeat spacing of the lamellae present in the semicrystalline growth rings. In agreement with current understanding of starch synthesis, amylose was shown to accumulate in both crystalline and amorphous parts of the lamella. Using waxy starch as a distinctive comparison with the other samples confirmed general trend of increasing amylose content being linked with the accumulation of defects within crystalline lamellae. Amylose content was shown to directly influence the architecture of semicrystalline lamellae, whereas thermodynamic and functional properties were proposed to be brought about by the interplay of amylose content and amylopectin architecture. Subjecting starch granules with varying amylose content to pancreatic α-amylase showed differences in their digestion patterns. Pancreatic α-amylase preferentially attacked amorphous regions of waxy starch granules, whereas these regions for initial preferential hydrolysis gradually diminished with increasing amylose content. Observed variations in the extent of enzymic digestion were concluded to be primarily determined by the level of swelling of amorphous growth rings, which can also explain observed morphologies of partly digested granules with varying amylose content. It was confirmed that access to the granular components is not a function of the extent of crystallinity but rather the spatial positioning of the crystalline regions within the granule. Digestion kinetics is governed by factors intrinsic to starch granules, whereas influence of enzyme type was shown to be critical in determining the absolute rate of hydrolysis. Wheat starches with increased amylose content offer the potential to be used as slow digestible starch, mostly in their granular form or when complexed with lipids. Differences among varieties largely diminished when starches were gelatinized or allowed to retrograde demonstrating the importance of granular structure on starch hydrolysis. Wheat varieties used in this study displayed widely differing pasting properties in a Rapid Visco Analyser (RVA) and textural characteristics of the respective retrograded starch gels. Varietal differences in starch chemical composition among wheat varieties were shown to have significant effect on the extent of the response of starch viscoelastic characteristics to the addition of monopalmitin. Amylose content was positively correlated with the increase in final viscosity, which was attributed to the presence of more amylose in non-aggregated state contributing to higher apparent viscosity of the starch paste. Comparison of stored gels obtained from amylose-rich starches with gel prepared from waxy wheat varieties confirmed the critical role of amylose on the formation of starch network and thus providing the strength of the gel. Lack of correlation between textural properties of stored gels with amylose content or rheological characteristics measured by the RVA indicated that subtle differences in starch structure may have far-reaching consequences in relation to the strength of the gels, although these differences may have only limited effect on pasting properties in the RVA Viscoelastic properties of starch paste prepared from commercial wheat starch were significantly altered depending on the chain length and saturation of the fatty acid of the monoglyceride added during repeated heating and cooling in the Rapid Visco Analyser. Varying effects of different monoglycerides on the paste viscosity were attributed to different complexation abilities of these lipids with starch. It was proposed that stability and structure of the starch-lipid complexes formed affect the viscosity trace of the paste subjected to multiple heating and cooling. Our study indicated that differing monoglycerides in combination with the number of heat-cool cycles can be used to induce form I or form II starch-lipid complexes and thus manipulate paste rheology, gel structure and resistant starch content.

Vete, Triticum aestivum är en mycket viktig matgröda. Under historiens gång har arten fått anpassa sig till många vitt skilda miljöer. I Nordeuropa har frost-resistens varit extra viktigt. En viktig gen för frostresistensen är VRN1som kontrollerar vernaliseringen d.v.s. övergången från vegetativt till aktivt tillstånd som sker på våren. Olika varianter av denna gen leder till skillnader frostresistens under våren. I detta arbete undersöktes hur variationer i promotorn till VRN1A i accessioner från norra Europa påverkar frostresistensen. Alla sorter som kunde sekvenseras visade sig ha samma promotor trots varierande frost-resistens. Detta kan bero på att promotorn till VRN1 inte är det enda som påverkar genens utryck. Även variationer i intron1 är betydelsefulla och det är därför rimligt att variationen mellan sorterna ligger där istället. En annan förklaring kan även vara att variationen ligger på ett annat genom då T. aestivum är hexaploid. Att alla sorter har samma promotorsekvens kan också tyda på ett selektivt svep. Detta selektiva svep har i så fall förekommit innan vete kom till Nordeuropa då även de franska och tyska sorterna har samma promotor som de finska och svenska. / Bread wheat, Triticum aestivum is an important crop. As history has progressed the species has been forced to adapt to different environments. In Northern Europe, frost resistance has been especially paramount. An important gene for frost resistance is VRN1 that controls vernalization, i.e. the transition from vegetative state to active state during spring. Different variants of this gene confer differences in frost resistance during spring. In this study I examined how the promotor region of VRN1A affects frost resistance in accessions of landraces of wheat from Northern Europe. All accessions from which the promotor region could be sequenced shared the same promotor sequence even though they had very varied frost resistance. This could be because the expression of VRN1 is not only affected by the promotor. Variations in intron one is also important, and so it is reasonable to assume that the variation between these landraces lies there instead. The variations could also be on one of the other genomes, because bread wheat is hexaploid. The fact that all the accessions shared the same promotor sequence indicates that a selective sweep has taken place. This selective sweep could have occurred before bread wheat arrived in Northern Europe because landraces from Germany and France shares the same promotor as Nordic Landraces.

No description available.

Considerable research has been concentrated on the foliage application of Cycoce, whereas little attention has focused on its use in seed application. Imbibition of caryopses of wheat (Triticum aestivum L.) in (2-chloroethyl) trimethylammonium chloride (Cycocel/CCC) resulted in a reduction in germination rate and a stunting of seedling growth. This was consistent with the appearance of a thicker stem, with shorter leaves than the control. Chlorophyll content per unit weight of leaf and numbers of tillers initiated both increased in comparison to controls. However, Cycocel treatment was accompanied by an enhanced survival capacity of seedlings when they were subjected to water limitation under growth room conditions. Seedlings grown from caryopses imbibed in 0.4 % Cycocel and exposed to a 7-day cycle of watering remained green and turgid beyond the time when the controls had wilted and died. Seedlings, at the fourth leaf stage, showed no wilting 23 days after watering had been withheld totally. Enhanced survival was also noted in seedlings when caryopses had been imbibed in Cycocel for 24 hours followed by a period of dry storage for up to 2 weeks prior to sowing. Enhanced survival was also detected as a carryover into the tillers, and the subsequent GEN2 seedlings, derived from GEN1plants. Cycocel pre-treatment did not alter Stomatal Index to an extent which could lead to enhanced water use efficiency, nor to the accumulation of proline to bring compatible solutes into equilibrium. However, the pre-treatment with Cycocel was found to enhance growth as a counter to water stress, and maintained fresh and dry weight of shoots when examined under the polyethylene glycol (PEG) induced stress. At the anatomical level the microscopic investigation of the GEN2 leaf tissues, derived from GENl plant, revealed a fully turgid cell structure, cells did not collapse and tissues were not distorted after the extraction of chlorophyll when compared with the control of the continuous watering as well as the moderate watering regime. Additionally, the cortex of GENl plants derived from pre-treated caryopses, showed a bright fluorescing unidentified deposition under Nutrient Solution (NS). This was more much greater when sampled from the NS + PEG treatments. From the results achieved Cycocel pre-treatment of caryopses appeared to have potential in manipulating wheat plants against water limitation. However, the mechanism (s) by which this can be achieved was not fully resolved in this study. Further investigations are required at the biochemistry and molecular level, particularly in relation to potential carryover effects between generations.