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

Cultura do quiabo submetida a lâminas de irrigação por gotejamento em função da evaporação em tanque Classe A /

Costa, Reinaldo Adriano, 1983. January 2014 (has links)
Orientador: Maria Helena Moraes / Banca: Thomaz Figueiredo Lobo / Banca: Antônio de Pádua Sousa / Banca: Pedro Rogério Giongo / Banca: Carolina Fernandes / Resumo: O presente estudo foi conduzido na área experimental da Universidade Estadual de Goiás, Unidade Universitária de Santa Helena de Goiás, com o objetivo de avaliar características no crescimento, desenvolvimento, produção da cultura do quiabeiro e eficiência do uso da água, sob diferentes lâminas de irrigação em função da evaporação em tanque Classe A. Os tratamentos foram constituídos por cinco porcentagens da evaporação em tanque Classe A (ECA), sendo elas: 0. 50, 75, 100 e 125%. A semeadura foi realizada dia 26 de junho, e o transplantio ocorreu no dia 12 de julho de 2012. Os dados foram coletados no período de 25 de agosto de 2012 a 15 de outubro de 2012. O manejo da irrigação foi realizado apartir de um tanque Classe A, instalado dentro da área experimental. As lâminas foram aplicadas com uso de um sistema de irrigação localizado por gotejamento, com vazão de 1,7 l h-1 submetido a uma pressão de serviço de 9 mca. Utilizou-se, um turno de rega fixo de 1 dia. Os parâmetros avaliados foram: diâmetro médio dos frutos (DF); comprimento médio dos frutos (CF); número de frutos por planta (NB); produtividade, produtividade (Prod), número de frutos por planta (NF), Massa úmida da parte da parte aérea (MUPA), Massa seca da parte aérea (MSPA), Massa úmida das raízes (MUR), massa seca da raiz (MSSR) e eficiência no uso da água pela cultura. A aplicação de diferentes lâminas de irrigação influenciou de forma significativa no desenvolvimento vegetativo, reprodutivo da cultura do quiabo. A lâmina 50% da ECA apresentou uma maior eficiência quanto ao uso da água na cultura do quiabo. O modelo linear melhor ajustou ao conjunto de dados médios do parâmetro número de brotações laterais, com isso havendo necessidade de testar novas lâminas para determinar a lâmina máxima recomendada. A lâmina de irrigação que proporciona a maior produtividade foi a de 102% da ECA / Abstract: The present study was conducted in the experimental area of the State University of Goiás, University Unit Santa Helena de Goiás, aiming to evaluate features in the growth, development, production culture of okra and efficiency of water use under different irrigation due to the evaporation tank in Class A. The treatments consisted of five percentages of Class A pan evaporation (ACE), as follows: 0. 50, 75, 100 and 125%. Sowing June 26 was performed, and the transplant took place on July 12, 2012. Data were collected between August 25, 2012 to October 15, 2012. Irrigation management was carried out starting from a Class A tank installed within the experimental area. The slides were applied using a system of drip irrigation located, with a flow rate of 1.7 L h-1 subjected to a pressure of 9 MCA service. We used a fixed irrigation for 1 day. The parameters evaluated were: average fruit diameter, average length of the fruit, number of fruits per plant, Productivity and Efficiency in water use by the crop. - The application of different irrigation had a significant influence on vegetative, reproductive development of the culture of okra. The blade 50 % of ECA showed greater efficiency in the use of water in the cultivation of okra. The best fit linear model to a set of parameter data, average number of side shoots, it is no need to further test strip to determine the maximum recommended blade. The depth of irrigation that delivers the highest productivity was 102% ECA / Doutor
12

Irrigation Methods and Their Effects on Irrigation Water Efficiency in High Tunnels

Young, Lauren 12 1900 (has links)
Improving water efficiency is and will continue to be a top concern to meet the world food production demands for a growing population. By having a clear understanding of water efficiencies, communities will be able to address these concerns from an economic standpoint and use more productive methods to grow food and limit water consumption. This study examines the water efficiencies of three irrigation methods over a single growing season in southeastern Oklahoma. Two crops, tomatoes and cucumbers, were grown using drip irrigation, a self-wicking container, and a non-circulating hydroponics barrel. Results at the end of the season showed the drip irrigation method had the highest water efficiency in terms of yield of product over water applied for both crops. The drip irrigation method also had the lowest associated set up costs and second lowest time requirements after the hydroponics method. These results were found to be consistent with other studies that compared drip irrigation to other irrigation methods and showed drip to have the highest water efficiencies.
13

Analysis of per capita water use patterns among communities with varying degrees of commercial activity

Unknown Date (has links)
Water supply managers often look for easily applied metrics to determine where water use can be curtailed. Unfortunately, the one-size-fits-all mentality comes with a price of failing to fully grasp the consequences decision-making based on such metrics. One issue that water supply regulator like to use is per capita water use. Per capital water use is often used to show where there is “wasted” water use, such as excessive irrigation. However such a metric may not be truly applicable depending on other economic factors. A heavily industrial area may add to apparent per capital use, but actually is an economic development activity. The focus of this project is to look at various water utilities and their per capital usage with the intent of discerning whether or not a better metric could be developed that consider the economic development activities of the region and water use. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
14

Resposta de cultivares de cana-de-açúcar a lâminas de irrigação via gotejamento subsuperficial /

Fischer Filho, João Alberto. January 2018 (has links)
Orientador: José Renato Zanini / Coorientador: Alexandre Barcellos Dalri / Banca: Regina Célia de Matos Pires / Banca: Dilermando Perecin / Banca: Roberto Lyra Villas Boas / Banca: Luiz Fabiano Palaretti / Resumo: A cana-de-açúcar é cultivada em muitos países e em diversos ambientes de produção, sendo a água um fator limitante para que a cultura tenha elevadas produtividades. O objetivo deste trabalho foi avaliar o efeito de lâminas de irrigação, via gotejamento subsuperficial, nas características biométricas, na qualidade tecnológica, produtividade e eficiência do uso da água (EUA) de cinco cultivares, em segunda soca. O delineamento experimental foi o de blocos balanceados, com 12 blocos e dois fatores: cultivares (CTC 4, IACSP93-3046, RB86-7515, IACSP95-5000 e IAC91-1099) e lâminas de irrigação (sequeiro, deficitária e suplementar). A necessidade de água foi estimada por meio das variáveis climáticas. A partir da evapotranspiração da cultura (ETc) estimada foram definidas lâminas de irrigação equivalentes a 100% da ETc para o tratamento suplementar e 50% para o deficitário, e a irrigação foi realizada sempre que ocorreu déficit de 20 mm . O uso da irrigação proporcionou condições para as plantas se estabelecerem e expressarem melhor suas características biométricas, principalmente no início do desenvolvimento vegetativo; com destaque as cultivares RB86-7515 (com maiores alturas, diâmetros de colmos e área foliar), a CTC 4 com maior perfilhamento e a IAC91-1099 (maiores números de folhas e índice de área foliar). Não foram encontradas diferenças estatísticas significativas para sólidos solúveis totais e teor de fibra. As quantidades de sacarose no caldo (POL) e na cana (PC) não difer... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Sugar cane is grown in many countries and diverse production environments, with water being a limiting factor for high crop yields. This study aimed to evaluate the effect of irrigation depths, under subsurface drip, on the biometric characteristics, technological quality, productivity and water use efficiency (WUE) of five cultivars in the third crop cycle . The experimental design was of balanced blocks, with 12 blocks and 2 factors: cultivars (CTC 4, IAC SP 93 - 3046, RB86 - 7515, IAC SP 95 - 5000 and IAC91 - 1099) and irrigation depths (dry, deficit and supplementary) . The need for water was estimated by means of climatic variables. From the evapotranspiration of the crop estimated ( ETc ) irrigation depths equivalent to 100% of the ETc were defined for the supplementary treatment and 50% for the deficit, and irrigation was performed whenever there was a deficit of 20 mm . The use of irrigation provided conditions for plants to establish and better express th eir biometric characteristics, especially at the beginning of vegetative development ; highlighting the cultivars RB86 - 7515 (with higher heights, plant diameters and leaf area), CTC 4 with higher tillering and IAC91 - 1099 (higher leaf numbers and leaf area i ndex). No significant statistical differences were found for total soluble solids and fiber content . The amounts of sucrose in the juice (POL) and the cane (PC) did not differ among the cultivars, however, additional irrigation provided higher values of th... (Complete abstract click electronic access below) / Doutor
15

Produtividade da cultura do feijão (Phaseolus vulgaris L.) irrigada por aspersão convencional com diferentes métodos de estimativa de lâmina de irrigação /

Faria, Manoel Teixeira de. January 2012 (has links)
Orientador: José Eduardo Pitelli Turco / Coorientador: Luiz Carlos Pavani / Banca: Antônio Carlos Barreto / Banca: José Renato Zanini / Banca: Renato Farias do Vale Junior / Banca: Rogério Teixeira de Faria / Resumo: Este trabalho foi realizado com o objetivo de determinar o manejo de irrigação mais adequado para a máxima produtividade da cultura do feijoeiro grupo carioca, cultivar pérola. O experimento foi conduzido na Área Demonstrativa e Experimental de Irrigação (ADEI) da FCAV/UNESP, Câmpus de Jaboticabal-SP. Foram definidos cinco tratamentos: TCA - irrigação com base na ET0 estimada pelo método do Tanque Classe A; RB - irrigações efetuadas com base na ETC medida pelo método da Razão de Bowen; TENS - irrigações baseadas em leituras de tensiômetros instalados nas profundidades de 0,20 e 0,40 m; PM - irrigações efetuadas com base na ET0 estimada pelo método de Penman-Monteith e Test. - testemunha. Os resultados foram submetidos à análise de variância. Para a comparação das médias, foi utilizado o teste de Tukey, a 5% de probabilidade. Na ausência de chuva em todo o ciclo da cultura, a máxima eficiência de uso da água aplicada em feijoeiro foi alcançada com a lâmina total de irrigação de 344,3 mm recebida pela cultura no tratamento da razão de Bowen. As variáveis de produção, número de vagens por planta, número de grãos por vagem e produtividade de grãos, na cultura do feijoeiro, responderam de forma linearmente crescente ao aumento das lâminas totais de irrigação aplicadas no intervalo (146,0 mm a 405,0 mm) / Abstract: The objective of this study was to analyze the most appropriate irrigation management to achieve the highest productivity for carioca beans (phaseolus vulgaris), perola cultivar. The research was developed in the Demonstrative and Experimental Area of Irrigation (ADEI) of FCAV/UNESP, Jaboticabal Campus, SP. Five treatments were set out: TCA - irrigation based in ETo estimated by the Class A pan method; RB - irrigation based in ETc measured by the Bowen ratio method, TENS - irrigation based on tensiometer readings installed at 0.20 m and 0.40 m of depth; PM - irrigation conducted with base in ETo estimated by the Penman-Monteith method and Test. - witness. The results were submitted to analysis of variance. To compare the averages the Tukey test was used at 5% of probability. In the absence of rain throughout the crop cycle, the maximum of water use efficiency applied on the beans was obtained by the total irrigation level of 344.3 mm received in the Bowen ratio method. The production variables, number of pods per plant, number of grains per pod and grain yield in the crop, responded linearly rising with the increased of total irrigation level applied in the range (146.0 mm to 405.0 mm) / Doutor
16

Produtividade da cultura do feijão (Phaseolus vulgaris L.) irrigada por aspersão convencional com diferentes métodos de estimativa de lâmina de irrigação

Faria, Manoel Teixeira de [UNESP] 01 August 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-08-01Bitstream added on 2014-06-13T19:01:13Z : No. of bitstreams: 1 faria_mt_dr_jabo.pdf: 645403 bytes, checksum: a7f38f2998ae0e8320d2dace89b81c88 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho foi realizado com o objetivo de determinar o manejo de irrigação mais adequado para a máxima produtividade da cultura do feijoeiro grupo carioca, cultivar pérola. O experimento foi conduzido na Área Demonstrativa e Experimental de Irrigação (ADEI) da FCAV/UNESP, Câmpus de Jaboticabal-SP. Foram definidos cinco tratamentos: TCA - irrigação com base na ET0 estimada pelo método do Tanque Classe A; RB - irrigações efetuadas com base na ETC medida pelo método da Razão de Bowen; TENS – irrigações baseadas em leituras de tensiômetros instalados nas profundidades de 0,20 e 0,40 m; PM – irrigações efetuadas com base na ET0 estimada pelo método de Penman-Monteith e Test. – testemunha. Os resultados foram submetidos à análise de variância. Para a comparação das médias, foi utilizado o teste de Tukey, a 5% de probabilidade. Na ausência de chuva em todo o ciclo da cultura, a máxima eficiência de uso da água aplicada em feijoeiro foi alcançada com a lâmina total de irrigação de 344,3 mm recebida pela cultura no tratamento da razão de Bowen. As variáveis de produção, número de vagens por planta, número de grãos por vagem e produtividade de grãos, na cultura do feijoeiro, responderam de forma linearmente crescente ao aumento das lâminas totais de irrigação aplicadas no intervalo (146,0 mm a 405,0 mm) / The objective of this study was to analyze the most appropriate irrigation management to achieve the highest productivity for carioca beans (phaseolus vulgaris), perola cultivar. The research was developed in the Demonstrative and Experimental Area of Irrigation (ADEI) of FCAV/UNESP, Jaboticabal Campus, SP. Five treatments were set out: TCA – irrigation based in ETo estimated by the Class A pan method; RB – irrigation based in ETc measured by the Bowen ratio method, TENS - irrigation based on tensiometer readings installed at 0.20 m and 0.40 m of depth; PM - irrigation conducted with base in ETo estimated by the Penman-Monteith method and Test. - witness. The results were submitted to analysis of variance. To compare the averages the Tukey test was used at 5% of probability. In the absence of rain throughout the crop cycle, the maximum of water use efficiency applied on the beans was obtained by the total irrigation level of 344.3 mm received in the Bowen ratio method. The production variables, number of pods per plant, number of grains per pod and grain yield in the crop, responded linearly rising with the increased of total irrigation level applied in the range (146.0 mm to 405.0 mm)
17

The effect of partial rootzone drying on the partitioning of dry matter, carbon, nitrogen and inorganic ions of grapevines.

Du Toit, Petrus Gerhardus January 2005 (has links)
Partial rootzone drying (PRD) is an irrigation management technique designed to reduce water use in grapevines without a decline in yield, thereby increasing water–use efficiency (measured as t/ML) (WUE). The principle of PRD is to keep part of the root system at a constant drying rate to produce soil-derived signals to above–ground plant organs to induce a physiological response. Major PRD effects include a reduced canopy size and greatly increased WUE with possible improvements in fruit quality. Although we have a good understanding of the hormonal physiology of PRD, little is known on the effect of PRD on partitioning of C, N and inorganic ions such as K. This thesis broadens our knowledge on the effects of PRD on grapevine field performance, growth and dry matter accumulation as well as its effects on physiology and biochemistry. In field experiments over 3 seasons, PRD reduced water use in grapevines without a significant decline in yield. PRD effects included reduced shoot growth and greatly increased WUE. Field–grown Cabernet Sauvignon, where the PRD grapevines were irrigated at half the control rate, and Shiraz where the PRD grapevines were irrigated at same rate as controls, confirmed that PRD is not simply an irrigation strategy that applies less water, rather it alters the way in which the plant responds to its environment, e.g. PRD alters the sensitivity of the stomatal response to atmospheric conditions and significantly influence enzymes that regulate nutrient accumulation and partitioning. PRD did not change the total amount of carbon and nitrogen on a whole plant basis. However, it caused a significant partitioning of carbon and nitrogen towards trunk, roots and fruit at the expense of shoot growth. This change in partitioning occurred as a result of altered activity of the enzymes controlling the assimilation of carbon and nitrogen. PRD significantly reduced nitrate reductase (NR) activity in grapevine leaves, which catalyses the first step in the assimilation of nitrate irrespective of the amount of water applied. The reduction in NR activity is correlated with the development of the PRD cycle and the associated reduction in stomatal conductance. PRD also significantly altered grapevine sucrolytic enzyme activity that regulate source:sink relationships. PRD showed transient increases in leaf sucrose phosphate synthase (SPS) activity (formation of sucrose) compared to control, but significantly reduced leaf neutral invertase (sucrose cleavage) and leaf starch content in both field and potted experiments. This may indicate an increased photosynthetic capacity and a reduction in its sink strength for sucrose in favor of organs such as fruit and roots. This hypothesis was reinforced by the fact that berries showed significantly higher levels in glucose and fructose early in the season. Berry sugar content and Brix at harvest however was unaffected. Although PRD had no significant effect on berry characteristics at harvest such as Brix and pH, it occasionally reduced per berry K+ content and increased total amino acid concentration that may lead to positive outcomes for wine quality. PRD–treated grapevine roots on the 'wet'– and 'drying'–sides differed greatly in enzyme activity and osmolality. PRD significantly increased osmolality in both wet and drying roots by increasing total osmolyte concentration that may facilitate the movement of water from wet to dry roots. The increases in osmolality were also associated with increased free polyamine production (spermidine and spermine) in PRD roots that may be related to increased root growth and density. / Thesis (Ph.D.)--School of Agriculture and Wine, 2005.
18

The effect of soil and irrigation management on grapevine performance.

Stewart, Diane January 2005 (has links)
The increasing demand worldwide for Australian wine has driven the recent expansion in vineyard plantings which in turn, has increased the requirement for irrigation water in grape growing regions. Large areas of Australia's national vineyard are already irrigated with relatively poor quality water and many districts have a limited supply of water available for irrigation. Therefore, improving the efficiency of vineyard irrigation is essential for the long term sustainability of the Australian wine industry. Reducing the volume of irrigation applied to vineyards can improve water use efficiency (WUE) and reduce vine vigour. However, it can be difficult to accurately apply the required degree of water stress and this may result in a yield reduction. An irrigation technique known as partial rootzone drying (PRD) involves applying a continuous water deficit to alternate sides of the root system while ensuring the other half is well watered. This has been found to increase WUE, reduce vine vigour, improve fruit quality but not affect vine yield. Where the soil volume available for root growth is limited, so too is the resultant vine growth and yield, as access to water and nutrients is restricted. Shallow soil profiles present a major limitation to root development and grapevine vigour. In shallow soils, mounding topsoil from the vineyard mid row to form raised beds in the vine row has been found to improve vine growth and productivity. Soil mounds tend to have a higher moisture holding capacity than flat soil but the greater surface area of the mound can increase surface evaporation. Applying mulch to the mound surface has been shown to reduce evaporative soil moisture loss and conserve irrigation water. The general hypothesis tested in this experiment was that: 'Combining soil mounding, straw mulch and partial rootzone drying (PRD) irrigation will improve grapevine growth and production and reduce levels of sodium and chloride in the vine.' The experiment was established on Vitis vinifera cv. Shiraz in a mature vineyard at Padthaway, South Australia, where the soil profile consisted of a shallow loam over clay and limestone. Soils of the experimental site were classified as moderately saline because their electrical conductivity (ECse) was greater than 4 dS/m. Three main factors, irrigation method (standard or PRD), soil mounding (flat or mounded) and surface cover (bare or straw mulch) were combined into a 2X2X2 factorial experiment such that the randomised block experiment comprised three replicates of eight treatments. The irrigation treatments were control (the application of water to both sides of the vines) and PRD (the application of water to one side of the vines only at any time). In the PRD treatment the frequency of alternating the 'wet' and 'dry' sides was determined according to soil moisture measurements and was typically every 5-7 days. It was very difficult to accurately schedule the irrigation at this site to avoid applying a moisture deficit to the PRD treatment. The shallow soil profile dried very quickly following irrigation and there were problems with the accuracy of the soil moisture sensing equipment for the duration of the experiment. As a result, PRD vines experienced repeated, excessive soil moisture deficits such that vine growth and production were significantly reduced each season. Shoot length was measured weekly during the growing season, while photosynthetically- active radiation (PAR), leaf area and canopy volume were measured at full canopy. Shoot number and pruning weight were measured during dormancy. All measures of vegetative growth (with the exception of PAR) were reduced in response to PRD. The decrease in lateral shoot growth for PRD resulted in greater bunch exposure and PAR. As a direct result of the severe soil moisture deficits experienced by the PRD treatment, all components of yield were significantly reduced compared to the control treatment each season. In particular, bunch weight and berry weight were significantly lower in the PRD treatment compared to the control, which suggests a period(s) of severe soil moisture deficit was experienced. Despite the yield loss sustained by the PRD treatment, WUE was improved compared to the control treatment in the first two years of this experiment. Berry anthocyanin levels were higher for the PRD treatment than the control but this may be due to the reduction in berry size. Weekly volumetric soil moisture monitoring showed that mounded soil was wetter than flat soil each year at similar horizons. In addition, the larger soil volume of the mounded treatment enhanced vine root development. Vegetative growth was greater in the mounded treatment than the flat treatment. Mounded vines grew more shoots than non-mounded vines, although there was no effect of mounding treatment on shoot length. The difference in shoot number was significant only in year 2, possibly due to the time required for vine roots to establish in the mounds. Pruning weight and mean shoot weight were higher for the mounded treatment each year and mounded vines grew more shoots than non-mounded vines in years 1 and 2. The increase in shoot weight of mounded vines, relative to non-mounded, was most likely due to the increase in lateral shoot growth which is supported by the lower PAR values of the mounded treatment compared to the flat treatment. Each year soil mounding resulted in higher vine yields than in flat soil beds as a direct result of the increased vine capacity of mounded vines. The mounded treatment had more shoots per vine than the non-mounded treatment and thus more bunches per vine. In addition, bunch weights were higher in the mounded treatment each year, due mainly to improved fruit set and more berries per bunch. Despite the mounded treatment resulting in a denser canopy than the non-mounded treatment this did not affect fruit composition in years 1 and 2. WUE was higher for the mound treatment in years 2 and 3 only, due to the volume of irrigation water applied being reduced, yet mounded vines continued to produce higher yields than non-mounded vines. In year 3, berries from vines grown in mounded soil had significantly higher pH than berries from vines grown in flat soil beds. Mounding treatment did not consistently affect berry anthocyanin or phenolic levels. Soil moisture levels were higher in the mulch treatment than the bare treatment in all seasons. In contrast to the mounding treatment, wetter soil did not consistently lead to improved vine growth or yield. Mulched vines developed fewer roots than non-mulched vines which is likely to have limited vine access to water and nutrients. As a result, shoot growth was similar for both treatments each season. The only significant difference between treatments for pruning weight was found in year 3 and was due entirely to shoot weight. The mulched treatment had lower PAR than the bare treatment in year 3, probably the result of increased lateral shoot growth and thus increased shoot weight, although this was not significant. PAR was significantly higher for the mulch treatment, compared to the bare treatment, in year 1 only but this was not supported by significant increases in vegetative growth. The mulch treatment resulted in higher vine yield than the non-mulch treatment in years 1 and 3. This difference was significant in year 3 only when both bunch number and bunch weight were significantly higher for mulched vines. In year 1 only bunch weight was significantly higher for mulched vines. Differences between treatments occurred in year 2 for fruit composition, specifically juice TA and anthocyanin levels. The mulch treatment had significantly higher TA and a significantly lower anthocyanin concentration in berries than the non-mulch treatment in year 2. There was no evidence of increased shading in the mulched treatment relative to the bare treatment that year but the difference in anthocyanin concentration may be explained by the significantly smaller berries of the bare treatment. Analysis of samples taken regularly from the soil profile and vine rootzone showed that there was no treatment effect on soil salinity but that soil ECse increased with soil depth and time each year. Petiole samples were collected at flowering, veraison and pre-harvest and levels were deemed toxic by pre-harvest each year. The PRD treatment received approximately 60% of the salt applied to the control treatment. This did not reduce ECse but did result in lower measures of sodium and chloride in petioles and juice at harvest. Vines grown in soil mounds had access to a greater volume of soil water than the non-mounded vines. The mounded treatment had higher levels of pre-harvest petiole chloride in years 1 and 3 but this was significant only in year 3. There was no consistent trend in levels of sodium and chloride in the juice from either mound treatment, although in year 3 berry extract chloride levels were found to be significantly higher in the mounded treatment than the flat treatment. Similarly, a consistent trend in sodium and chloride levels of petioles and juice was not evident for the mulch treatment. Although, in year 3 petioles of vines grown in bare soil were found to contain significantly more petiole chloride than those which had straw mulch applied. The hypothesis that combining soil mounding, straw mulch and partial rootzone drying (PRD) irrigation will improve grapevine growth and production and reduce levels of sodium and chloride in the vine is rejected as there was not a consistent, cumulative effect of the three factors in this experiment. / Thesis (M.Ag.Sc.)--School of Agriculture and Wine, 2005.
19

The effect of soil and irrigation management on grapevine performance.

Stewart, Diane January 2005 (has links)
The increasing demand worldwide for Australian wine has driven the recent expansion in vineyard plantings which in turn, has increased the requirement for irrigation water in grape growing regions. Large areas of Australia's national vineyard are already irrigated with relatively poor quality water and many districts have a limited supply of water available for irrigation. Therefore, improving the efficiency of vineyard irrigation is essential for the long term sustainability of the Australian wine industry. Reducing the volume of irrigation applied to vineyards can improve water use efficiency (WUE) and reduce vine vigour. However, it can be difficult to accurately apply the required degree of water stress and this may result in a yield reduction. An irrigation technique known as partial rootzone drying (PRD) involves applying a continuous water deficit to alternate sides of the root system while ensuring the other half is well watered. This has been found to increase WUE, reduce vine vigour, improve fruit quality but not affect vine yield. Where the soil volume available for root growth is limited, so too is the resultant vine growth and yield, as access to water and nutrients is restricted. Shallow soil profiles present a major limitation to root development and grapevine vigour. In shallow soils, mounding topsoil from the vineyard mid row to form raised beds in the vine row has been found to improve vine growth and productivity. Soil mounds tend to have a higher moisture holding capacity than flat soil but the greater surface area of the mound can increase surface evaporation. Applying mulch to the mound surface has been shown to reduce evaporative soil moisture loss and conserve irrigation water. The general hypothesis tested in this experiment was that: 'Combining soil mounding, straw mulch and partial rootzone drying (PRD) irrigation will improve grapevine growth and production and reduce levels of sodium and chloride in the vine.' The experiment was established on Vitis vinifera cv. Shiraz in a mature vineyard at Padthaway, South Australia, where the soil profile consisted of a shallow loam over clay and limestone. Soils of the experimental site were classified as moderately saline because their electrical conductivity (ECse) was greater than 4 dS/m. Three main factors, irrigation method (standard or PRD), soil mounding (flat or mounded) and surface cover (bare or straw mulch) were combined into a 2X2X2 factorial experiment such that the randomised block experiment comprised three replicates of eight treatments. The irrigation treatments were control (the application of water to both sides of the vines) and PRD (the application of water to one side of the vines only at any time). In the PRD treatment the frequency of alternating the 'wet' and 'dry' sides was determined according to soil moisture measurements and was typically every 5-7 days. It was very difficult to accurately schedule the irrigation at this site to avoid applying a moisture deficit to the PRD treatment. The shallow soil profile dried very quickly following irrigation and there were problems with the accuracy of the soil moisture sensing equipment for the duration of the experiment. As a result, PRD vines experienced repeated, excessive soil moisture deficits such that vine growth and production were significantly reduced each season. Shoot length was measured weekly during the growing season, while photosynthetically- active radiation (PAR), leaf area and canopy volume were measured at full canopy. Shoot number and pruning weight were measured during dormancy. All measures of vegetative growth (with the exception of PAR) were reduced in response to PRD. The decrease in lateral shoot growth for PRD resulted in greater bunch exposure and PAR. As a direct result of the severe soil moisture deficits experienced by the PRD treatment, all components of yield were significantly reduced compared to the control treatment each season. In particular, bunch weight and berry weight were significantly lower in the PRD treatment compared to the control, which suggests a period(s) of severe soil moisture deficit was experienced. Despite the yield loss sustained by the PRD treatment, WUE was improved compared to the control treatment in the first two years of this experiment. Berry anthocyanin levels were higher for the PRD treatment than the control but this may be due to the reduction in berry size. Weekly volumetric soil moisture monitoring showed that mounded soil was wetter than flat soil each year at similar horizons. In addition, the larger soil volume of the mounded treatment enhanced vine root development. Vegetative growth was greater in the mounded treatment than the flat treatment. Mounded vines grew more shoots than non-mounded vines, although there was no effect of mounding treatment on shoot length. The difference in shoot number was significant only in year 2, possibly due to the time required for vine roots to establish in the mounds. Pruning weight and mean shoot weight were higher for the mounded treatment each year and mounded vines grew more shoots than non-mounded vines in years 1 and 2. The increase in shoot weight of mounded vines, relative to non-mounded, was most likely due to the increase in lateral shoot growth which is supported by the lower PAR values of the mounded treatment compared to the flat treatment. Each year soil mounding resulted in higher vine yields than in flat soil beds as a direct result of the increased vine capacity of mounded vines. The mounded treatment had more shoots per vine than the non-mounded treatment and thus more bunches per vine. In addition, bunch weights were higher in the mounded treatment each year, due mainly to improved fruit set and more berries per bunch. Despite the mounded treatment resulting in a denser canopy than the non-mounded treatment this did not affect fruit composition in years 1 and 2. WUE was higher for the mound treatment in years 2 and 3 only, due to the volume of irrigation water applied being reduced, yet mounded vines continued to produce higher yields than non-mounded vines. In year 3, berries from vines grown in mounded soil had significantly higher pH than berries from vines grown in flat soil beds. Mounding treatment did not consistently affect berry anthocyanin or phenolic levels. Soil moisture levels were higher in the mulch treatment than the bare treatment in all seasons. In contrast to the mounding treatment, wetter soil did not consistently lead to improved vine growth or yield. Mulched vines developed fewer roots than non-mulched vines which is likely to have limited vine access to water and nutrients. As a result, shoot growth was similar for both treatments each season. The only significant difference between treatments for pruning weight was found in year 3 and was due entirely to shoot weight. The mulched treatment had lower PAR than the bare treatment in year 3, probably the result of increased lateral shoot growth and thus increased shoot weight, although this was not significant. PAR was significantly higher for the mulch treatment, compared to the bare treatment, in year 1 only but this was not supported by significant increases in vegetative growth. The mulch treatment resulted in higher vine yield than the non-mulch treatment in years 1 and 3. This difference was significant in year 3 only when both bunch number and bunch weight were significantly higher for mulched vines. In year 1 only bunch weight was significantly higher for mulched vines. Differences between treatments occurred in year 2 for fruit composition, specifically juice TA and anthocyanin levels. The mulch treatment had significantly higher TA and a significantly lower anthocyanin concentration in berries than the non-mulch treatment in year 2. There was no evidence of increased shading in the mulched treatment relative to the bare treatment that year but the difference in anthocyanin concentration may be explained by the significantly smaller berries of the bare treatment. Analysis of samples taken regularly from the soil profile and vine rootzone showed that there was no treatment effect on soil salinity but that soil ECse increased with soil depth and time each year. Petiole samples were collected at flowering, veraison and pre-harvest and levels were deemed toxic by pre-harvest each year. The PRD treatment received approximately 60% of the salt applied to the control treatment. This did not reduce ECse but did result in lower measures of sodium and chloride in petioles and juice at harvest. Vines grown in soil mounds had access to a greater volume of soil water than the non-mounded vines. The mounded treatment had higher levels of pre-harvest petiole chloride in years 1 and 3 but this was significant only in year 3. There was no consistent trend in levels of sodium and chloride in the juice from either mound treatment, although in year 3 berry extract chloride levels were found to be significantly higher in the mounded treatment than the flat treatment. Similarly, a consistent trend in sodium and chloride levels of petioles and juice was not evident for the mulch treatment. Although, in year 3 petioles of vines grown in bare soil were found to contain significantly more petiole chloride than those which had straw mulch applied. The hypothesis that combining soil mounding, straw mulch and partial rootzone drying (PRD) irrigation will improve grapevine growth and production and reduce levels of sodium and chloride in the vine is rejected as there was not a consistent, cumulative effect of the three factors in this experiment. / Thesis (M.Ag.Sc.)--School of Agriculture and Wine, 2005.
20

Características agronômicas e tecnológicas de variedades de sorgo sacarino e propriedades do solo em função de lâminas de irrigação por gotejamento /

Silva, Patrícia Costa, 1979. January 2018 (has links)
Orientador: Maria Helena Moraes Spinelli / Banca: Hélio Grassi Filho / Banca: Iraê Amaral Guerrini / Banca: Ricardo Alexandre Lambert / Banca: Aline Azevedo Nazario / Resumo: O cultivo de sorgo sacarino surgiu como alternativa para produção de massa destinada à fabricação de etanol, na entressafra, e em áreas de reforma do canavial e em áreas de rotação à outras culturas. Ainda são escassos estudos sobre a irrigação em sorgo sacarino, bem como os estudos que correlacionam lâminas de irrigação e a dinâmica dos nutrientes no solo e propriedades físicas. Este estudo teve como objetivos analisar o efeito da aplicação de lâminas de irrigação sob características tecnológicas e agronômicas de variedades de sorgo sacarino e nas propriedades do solo, e avaliar a eficiência do uso da água. O experimento foi conduzido em campo na área experimental da Universidade Estadual de Goiás, Câmpus de Santa Helena de Goiás. O delineamento adotado foi o de blocos casualizados com esquema fatorial 5x3, com 5 tratamentos, 3 cultivares de sorgo sacarino e 4 repetições. Os tratamentos foram constituídos por 5 lâminas de irrigação: 25, 50, 75, 100 e 125 % da evapotranspiração de cultura (ETc) e as variedades avaliadas foram BRS 511, CVSW 80007 e Silotec 20. O sistema de irrigação empregado foi o localizado por gotejamento. Os dados foram submetidos à análise de variância pelo teste F a 5% de significância. As médias para o fator variedades e propriedades do solo foram comparadas pelo teste de Tukey e para o fator lâminas de irrigação empregou-se a análise de regressão. Verificou-se que as lâminas de irrigação exerceram influência significativa nas características agronômica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cultivation of sorghum emerged as an alternative for the production of mass destined to the manufacture of ethanol, in the off season, and in areas of reforestation of cane fields and in areas of rotation to other crops. There are still few studies on irrigation in sorghum, as well as studies that correlate irrigation slides and the dynamics of soil nutrients and physical properties. The objective of this study was to analyze the effect of the application of irrigation slides under the technological and agronomic characteristics of sorghum varieties and soil properties, and to evaluate the efficiency of water use. The experiment was conducted in the experimental area of the State University of Goiás, Campus of Santa Helena de Goiás. The experiment was a randomized complete block design with 5x3 factorial, with 5 treatments, 3 sorghum cultivars and 4 replicates. The treatments consisted of 5 irrigation slides: 25, 50, 75, 100 and 125% of crop evapotranspiration (ETc) and the varieties evaluated were BRS 511, CVSW 80007 and Silotec 20. The irrigation system was located by drip. The data were submitted to analysis of variance by the F test at 5% of significance. The averages for the factor varieties and soil properties were compared by the Tukey test and for the irrigation lamina factor the regression analysis was used. It was verified that the irrigation slides exerted significant influence on the agronomic and technological characteristics. The BRS 511 variety was better adapted to local edaphoclimatic conditions with higher plant height, stem diameter, number of leaves and internodes, leaf percentage, shoot yield, shoot shoot mass, broth yield, seed yield ethanol and total soluble solids; and lower weight of the wet cake and industrial fiber content. Comparing the varieties on each slide, a variation was observed from the 75% replacement blade of the crop evapotranspiration with linear and ... / Doutor

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