Made available in DSpace on 2016-12-06T17:42:05Z (GMT). No. of bitstreams: 1 PGPV14DA009.pdf: 2537608 bytes, checksum: 52becf46e22999496c3c26525a0865d0 (MD5) Previous issue date: 2014-10-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The culture of pear (Pyrus communis L.), has great potential for expansion in Southern Brazil due to climate and soil conditions. The lack of information regarding the (s) best (s) combination (s) of european pear cultivars scion and quince rootstocks as vegetative aspect and productive potential has limited the cultivation of pear in the country. In this contexto, the objetive was to evaluate the agronomic aspects of vegetative and productive cultivars scioneuropean pear (Pyrus communis. L) grafted on quince rootstocks (Cydonia oblonga. L) in médium systems, super and high planting densities, at conditions the conditions of the Santa Catarina plateau. The experiments were conducted in the área of company experimental Agrícola Fraiburgo S/A, located in Urupema, state of Santa catarina, during the cropping cycles 2011/12, 12/23 and 13/14. In Chapter I, we used three systems, characterized as average (2500 plants ha¯¹), high (5000 plants ha¯¹) and super (7500 plants ha¯¹) densities. In médium density system, the combinations evaluated among european pear cultivars and quince rootstocks were: Abbè Fetel/Adams Conference/Adams, Clapp s Favourite/EMA, Santa Maria/Adams, rocha/Adams, Packham s Triumph/Adams, Decana du Comice/Adams e Packam s Triumph/EMA. In high density planting combinations were evaluated: Conference/EMC, Clapp s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William s/EMC e Packham s/EMA. In the super density, evaluated the combinations: Rocha/Adams, Santa Maria/Adams, Packam s Triumph/EMC, Abbè Fetel/EMC, Abbè Fetel/Adams and Rocha/EMC. In Chapter II, we evaluated the compartibility of grafting, which consisted in the analysis of growth and vascular grafting connection in the following combinations: Abbè Fetel/Adams, Decana du Comice/Adams, Clapp s Favourite/EMA, Rocha/Adams, Packham s Triumph/EMA and Santa Maria/Adams density of 2500 plants ha¯¹ and Rocha/EMC, Abbè Fetel/EMC and William s/EMC density of 5000 plants ha¯¹. In chapter III, we evaluated the distribution of the root system of diferente combinations of european pear cultivars scion and quince rootstocks at planting density of 2500 plants ha¯¹ with the following combinations: Abbè Fetel/Adams, Clapp s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Decana du Comice/Adams and Packham s Triumph/EMA and density of 5000 plants ha¯¹: Conference/EMC, Clapp s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William s/EMC e Packham s Triumph/EMA. The combination Abbè Fetel/Adams is more vigorou, reporting low yield in médium super system and planting density. The combination Santa Maria grafted on quince Adams gives intermediate vegetative growth of plants and high producrtivity in médium system and super planting density. Combinations Clapp s Favourite/EMA and William s/EMC are incompatible with quince rootstocks of tested, it is possible to observe a clear discontinuity in the region of vascular graft union. Santa Maria and Rocha grafted on quince Adams exhibit a continous vascular union between cultivar and rootstock, with no symptoms of vascular disruption at any level. In planting density of 2500 plants ha¯¹, to jointly analyse the six combinations of european pear cultivars and quince rootstocks throught the spatial distribution of root length at depth, there was a higher concentration of roots in the first 40 cm of depth. Regarding the effective depth, it was observed that up to 40 cm depth concentrate 80% of the total root for all combinations of the average and six combinations evaluated, 83% of root geowth is located on the respective depth. Regarding the effective distance, it was observed that the distance at which are 80% of total root length was 80 cm for all combinations exceptd the Clapp s FAvourite/EMA, which the effective distance was 100 cm. Irt was observed that the average of the six combinations,86% of root growth in horizontal distance located up to 80 cm. Already at a density of 5000 plants ha¯¹ jointly analyzing the six combinations of euroepean pears cultivars and rootstocks quince, it was observed that the greatest concentration of the first roots 40 cm deep, about 90% of the distribution root. Regarding combinations evaluated, it was observed that cv. Packham s Triumph grafted on quince EMA provided greater root growth, and may infer that their combination, compared to the other, exploring a greater volume of soil in the planting density of 5000 plants ha¯¹ and is able to check out the shoot of plant vigor. Regarding the effective depth, it was observed that up to 30 cm deep focus 80% of total root length, evaluated for all combinations except the comnbination William s/EMC that got in this depth, only 60% of root volume. For this combination in particular, has been considered effective depth of 40 cm. As the density of 2500 plants ha¯¹ at a density of 5000 ha¯¹ plants, the major root length also concentrated in the largest amount of available nutrientes and water to the roots region, which should ensure a greater capacity of the plant cultivation of the soil, and thus greater absorption of water nutrients / A cultura da pereira (Pyrus communis. L), possui potencial de expansão em algumas regiões do sul do Brasil, devido às condições climáticas e de solo. A despeito disso, a carência de informações a respeito da(s) melhor(es) combinação(ões) entre cultivares copa de pereiras europeias e portaenxertos de marmeleiro quanto ao aspecto vegetativo e ao potencial produtivo tem limitado a produção de pera no país. Neste contexto, o objetivo do trabalho foi avaliar agronomicamente os aspectos vegetativos e produtivos de cultivares copa de pereiras europeias (Pyrus communis. L) enxertadas sobre portaenxertos de marmeleiro (Cydonia oblonga. L) em sistemas de média, alta e super densidades de plantio, nas condições edafoclimáticas da região do planalto catarinense. Os experimentos foram conduzidos na área experimental da empresa Agrícola Fraiburgo S/A, localizada na cidade de Urupema, estado de Santa Catarina, durante os ciclos de cultivo 2011/12, 12/13 e 13/14. No capítulo I, utilizou-se três sistemas, caracterizados como média (2500 plantas ha-1), alta (5000 plantas ha-1) e super (7500 plantas ha-1) densidades de plantio. No sistema de média densidade, as combinações avaliadas entre cultivares de pereiras europeias e portaenxertos de marmeleiro foram: Abbè Fetel/Adams, Conference/Adams, Clapp´s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Packham´s Triumph/Adams, Decana du Comice/Adams e Packham´s Triumph/EMA. Na alta densidade de plantio, foram avaliadas as combinações: Conference/EMC, Clapp´s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William´s/EMC e Packham´s Triumph/EMA. Já na super densidade, avaliaram-se as combinações: Rocha/Adams, Santa Maria/Adams, Packham´s Triumph/EMC, Abbè Fetel/EMC, Abbè Fetel/Adams e Rocha/EMC. No capítulo II, avaliou-se a compatibilidade de enxertia, que consistiu na análise de crescimento e conexão vascular no ponto de enxertia das seguintes combinações: Abbè Fetel/Adams, Decana du Comice/Adams, Clapp´s Favourite/EMA, Rocha/Adams, Packham´s Triumph/EMA e Santa Maria/Adams na densidade de 2500 plantas ha-1 e Rocha/EMC, Abbè Fetel/EMC e William´s/EMC para a densidade de 5000 plantas ha-1. No capítulo III, avaliou-se a distribuição do sistema radicular das diferentes combinações de cultivares copa de pereiras europeias e portaenxertos de marmeleiro. Na densidade de plantio de 2500 plantas ha-1, utilizou-se as seguintes combinações: Abbè Fetel/Adams, Clapp´s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Decana du Comice/Adams e Packham´s Triumph/EMA enquanto que na densidade de 5000 plantas ha-1: Conference/EMC, Clapp´s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William´s/EMC e Packham´s Triumph/EMA. A combinação Abbè Fetel/Adams é mais vigorosa, reportando baixo rendimento em sistema de média e super densidade de plantio. A combinação Santa Maria enxertada sobre o marmeleiro Adams, confere crescimento vegetativo intermediário às plantas e alta produtividade em sistema de média e super densidade de plantio. As combinações Clapp´s Favourite/EMA e William´s/EMC são incompatíveis com os portaenxertos de marmeleiros testados, sendo possível observar uma clara descontinuidade vascular na região de união do enxerto. Santa Maria e Rocha enxertadas sobre o marmeleiro Adams, apresentam uma união vascular contínua entre cultivar e portaenxerto, não havendo sintomas de descontinuidade vascular em nenhum nível. Para a densidade de plantio de 2500 plantas ha-1, observou-se maior concentração de raízes nos primeiros 40 cm de profundidade. Em relação à profundidade efetiva, observou-se que até 40 cm de profundidade concentram-se 80% do comprimento total de raízes para todas as combinações e que na média das seis combinações avaliadas, 83% da concentração radicular localiza-se na respectiva profundidade. Em relação à distância efetiva, observou-se que a distância na qual se encontram 80% do comprimento total de raízes foi 80 cm para todas as combinações, com exceção da Clapp´s Favourite/EMA, a qual a distância efetiva foi 100 cm. Foi possível observar que na média das seis combinações, 86% da concentração radicular na distância horizontal localiza-se até 80 cm. Já na densidade de 5000 plantas ha-1, analisando conjuntamente as seis combinações de cultivares de pereiras europeias e portaenxertos de marmeleiro, observou-se que há maior concentração de raízes nos primeiros 40 cm de profundidade, cerca de 90 % de toda a distribuição do sistema radicular. Em relação às combinações avaliadas, observou-se que a cv. Packham´s Triumph enxertada sobre o marmeleiro EMA proporcionou maior crescimento de raízes, podendo inferir que a respectiva combinação, comparada às demais, explora um maior volume de solo na densidade de plantio de 5000 plantas ha-1. Em relação à profundidade efetiva, observou-se que até 30 cm de profundidade se concentram 80 % do comprimento total de raízes, para todas as combinações avaliadas, com exceção da combinação William´s/EMC que obteve na respectiva profundidade, apenas 60% de volume radicular. Para esta combinação, a profundidade considerada efetiva foi de 40 cm. Assim como na densidade de 2500 plantas ha-1, na densidade de 5000 plantas ha-1, o maior comprimento radicular também concentrou-se na região de maior quantidade de água e nutrientes disponíveis às raízes, o que deve assegurar à planta maior capacidade de exploração do solo e, por conseguinte, maior absorção de água e nutrientes

During embryogenesis and post-embryonic patterning, active transport of the phytohormone auxin, reflected in the expression of the Arabidopsis PIN family of auxin efflux mediators, generates local auxin distributions that are crucial for correct organ and tissue specification. Polar auxin transport routes have also long been postulated to regulate vein formation in the leaf. The molecular identification of PIN proteins has made it possible to investigate this hypothesis further by visualizing auxin transport routes in developing leaves. In Arabidopsis leaf primordia, PIN1 is expressed before the earliest known markers of vascular identity, in domains that are gradually restricted to sites of vein formation. PIN1 polarity indicates that auxin is directed towards distinct “convergence points” (CPs) in the marginal epidermis, from which it defines the sites of major vein formation. Within incipient veins, PIN1 polarity indicates drainage of auxin into preexisting veins, such that veins connected at both ends display two divergent polarities. Local auxin application triggers the formation of ectopic CPs and new veins, demonstrating the sufficiency of auxin as a vein-specifying signal. However, not all PIN1-labeled auxin transport routes differentiate as veins: Minor veins are initially unstable, suggesting local competition for auxin transport. Expression of ATHB8, a marker of vascular cell selection, correlates with enhanced PIN1 expression domain (PED) stability and vascular differentiation. Auxin application and auxin transport inhibition reveal that both CP formation in the epidermis and subepidermal PED dynamics are auxin-dependent and self-organizing. Furthermore, normal auxin perception through the ARF-Aux/IAA signaling pathway is required for the restriction of PIN1-mediated auxin transport to narrow subepidermal domains. ARF-Aux/IAA signaling is known to control auxin transport through the regulation of PIN1 dynamics, but the mechanism of this regulation is unclear. It is here shown that two redundantly acting AUXIN RESPONSE FACTOR (ARF) transcription factors, ARF5/MONOPTEROS (MP) and ARF7/NPH4, jointly regulate both PIN1 expression and localization during lateral root patterning in Arabidopsis, in part through the direct transcriptional activation of PIN1 by MP. Taken together, these results indicate that feedback between PIN-mediated auxin transport and ARF-Aux/IAA signaling regulates the patterning of root and shoot organs.

During embryogenesis and post-embryonic patterning, active transport of the phytohormone auxin, reflected in the expression of the Arabidopsis PIN family of auxin efflux mediators, generates local auxin distributions that are crucial for correct organ and tissue specification. Polar auxin transport routes have also long been postulated to regulate vein formation in the leaf. The molecular identification of PIN proteins has made it possible to investigate this hypothesis further by visualizing auxin transport routes in developing leaves. In Arabidopsis leaf primordia, PIN1 is expressed before the earliest known markers of vascular identity, in domains that are gradually restricted to sites of vein formation. PIN1 polarity indicates that auxin is directed towards distinct “convergence points” (CPs) in the marginal epidermis, from which it defines the sites of major vein formation. Within incipient veins, PIN1 polarity indicates drainage of auxin into preexisting veins, such that veins connected at both ends display two divergent polarities. Local auxin application triggers the formation of ectopic CPs and new veins, demonstrating the sufficiency of auxin as a vein-specifying signal. However, not all PIN1-labeled auxin transport routes differentiate as veins: Minor veins are initially unstable, suggesting local competition for auxin transport. Expression of ATHB8, a marker of vascular cell selection, correlates with enhanced PIN1 expression domain (PED) stability and vascular differentiation. Auxin application and auxin transport inhibition reveal that both CP formation in the epidermis and subepidermal PED dynamics are auxin-dependent and self-organizing. Furthermore, normal auxin perception through the ARF-Aux/IAA signaling pathway is required for the restriction of PIN1-mediated auxin transport to narrow subepidermal domains. ARF-Aux/IAA signaling is known to control auxin transport through the regulation of PIN1 dynamics, but the mechanism of this regulation is unclear. It is here shown that two redundantly acting AUXIN RESPONSE FACTOR (ARF) transcription factors, ARF5/MONOPTEROS (MP) and ARF7/NPH4, jointly regulate both PIN1 expression and localization during lateral root patterning in Arabidopsis, in part through the direct transcriptional activation of PIN1 by MP. Taken together, these results indicate that feedback between PIN-mediated auxin transport and ARF-Aux/IAA signaling regulates the patterning of root and shoot organs.

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / The root system of shrub live oak (Quercus turbinella) was studied in an initial effort to classify the major Arizona chaparral shrubs as potential users of soil water based on root system characteristics. The root system was of the generalized type with a taproot, many deeply penetrating roots, and a strong lateral root system. Roots penetrated 21 feet to bedrock through cracks and fractures in the rocky regolith. A dense network of small surface laterals radiated from the root crown and permeated the upper foot of soil. Because of its root system, shrub live oak is well adapted to utilize both ephemeral surface soil moisture as well as deeply stored moisture. Emphasis is placed on the importance of a knowledge of the root systems of chaparral shrubs and depth of the regolith in planning vegetation conversions to increase water yield.

Studies were conducted on three field trials of wheat cv. Kopara to investigate the lack of compensation by later determined components of yield because of early disease constraints. The investigation was based on the hypothesis that early disease reduces root development and thus causes the plants to be water constrained at later growth stages when soil water deficits usually occur. The reduced root development and soil water deficits may reduce the ability of the plant to compensate for reductions in early determined components. The hypothesis was tested by the application of irrigation to alleviate water stress. In a disease free crop, the possible phytotonic effects of the fungicides benomyl and triadimefon on wheat were investigated. These fungicides had no phytotonic effects on shoot, root growth, or yield under the prevailing conditions. The effect of disease on root development was analysed by root length measurements. Disease present in the crop at any stage of growth affected root development. Root development in the upper zones of the soil profile was reduced more by disease compared to those zones below 35 cm. A full disease epidemic reduced root development more than an early or late disease epidemic. The early and late disease epidemics had similar effects on root length. Alleviation of early disease constraints enabled greater development of roots to offset any earlier reductions. Soil water deficits increased root development in the lower zones of the nil disease plants. The presence of adequate soil water from irrigation reduced the requirement for further root growth in all treatments. In the 1981-1982 field trial a full disease epidemic reduced yield by 14% whereas an early disease epidemic reduced yield by 7%. The reduction in yield was attributed to a lower grain number. With irrigation the yield reduction in the full disease plants was 12% whereas in the early disease plants the reduction was only 2.4%. This indicated that plants affected by the early disease epidemic were water constrained. In this study, the results suggested that, for conditions prevailing in Canterbury, the supply of water at later growth stages increased grain weight in plants which were subject to early disease epidemics. This suggests that reduced root development caused by early disease and soil water deficits may prevent compensation by grain weight. Water use was similar in all disease treatments. After irrigation the irrigated plants of all treatments used more water. Disease affected water use in relation to yield production however, and was better expressed by water use efficiency. Water use efficiency was reduced in the full disease plants. A stepwise regression analysis suggested that water use efficiency was affected directly by disease at later growth stages, and indirectly via an effect on total green leaf area at early growth stages. This study partially proves the hypothesis that reductions in root development caused by an early disease epidemic may constrain the plants at later growth stages when water deficits usually occur. It was shown that the reduction in root development caused by disease could be counteracted by irrigation. In this respect, water served as a tool to study the effect of disease constraints on the yield of wheat. A knowledge of cereal crop physiology, root growth and function is used to explain and discuss the observations made in this research programme. The results are discussed in relation to the way in which disease affects yield through its effect on root development. The possible reasons for the continued effects of disease even after the control of disease at later growth stages are discussed. The economic use of fungicides and water in diseased crops are also outlined. Suggestions for future studies on disease-yield loss relationships are provided. The repetition of these experiments in different sites and climatic regions could provide information which may be incorporated in disease-yield loss simulation models. This could then be used to predict root development and water requirements of diseased plants, and provide a basis for economic use of fungicides and water, and for better disease management programmes.