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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.
41

Teor e rendimento de flavonóides em calêndula (Calendula officinalis L.) cultivada com diferentes lâminas de irrigação / ABSTRACT Content and yield of flavonoids in marigold plant (Calendula officinalis L.) under different irrigation depths

Bortolo, Daniela Perez Guerrero 24 September 2008 (has links)
Made available in DSpace on 2016-01-26T18:56:18Z (GMT). No. of bitstreams: 1 Dissertacao Daniela.pdf: 200686 bytes, checksum: 738c24570a7f86211f674f2c744f2487 (MD5) Previous issue date: 2008-09-24 / Calendula officinalis L. could be used as ornamental, culinary and therapeutic. The inflorescence is used as healing and anti-inflammatory. This experiment analyzed the effect of four different irrigations depth under field conditions in the production of flavonoids in the marigold plant (Calendula officinalis L.). The water depths were estimated upon the class A pan evaporation (CPE): 0, 50, 100 and 150% CPE. The depths were applied since of the beginning flowering until the end of culture cycle. There were no statistical differences in the flavonoids content. The higher dry weight flowers and flavonoids yield were obtained with the treatment without irrigation. The higher content of proline was found stressing the overwatering treatment. The accumulated water deficit for the treatment without irrigation signalized possible death by water deficit. With the precipitation occurrence in the pre-flowering, the plant, originated in the Mediterranean Basin, answered with abundant flourishment, in mass and in number of flowers. For Presidente Prudente region (São Paulo State, Brazil), if did not occur water replacement only in the pre-flowering, it will be necessary supplementary irrigation of 200 mm to induce the maximum flowering and yield per hectare of flavonoids. / A Calendula officinalis L. apresenta uso ornamental, culinário e terapêutico. A inflorescência é usada com ação cicatrizante e antiinflamatória. O experimento analisou o efeito de quatro lâminas de irrigação em condições de campo, na produção de flavonóides em calêndula. As lâminas baseadas na evaporação do Tanque Classe A (ECA) foram: 0, 50, 100 e 150% ECA; sendo aplicadas desde o início do florescimento até o final do ciclo da cultura. O teor de flavonóides não apresentou diferenças estatísticas. Os maiores valores de matéria seca de flores e rendimento de flavonóides foram obtidos no tratamento sem irrigação. O teor de prolina foi maior para o tratamento com estresse por excesso hídrico. A deficiência hídrica acumulada para o tratamento sem irrigação sinalizou uma possível morte por deficiência hídrica. Com a ocorrência da precipitação no período de pré-florescimento, a planta, originária do Mediterrâneo, respondeu com um florescimento abundante em massa e em número de flores. Assim, para região de Presidente Prudente São Paulo, caso não ocorra a reposição hídrica do solo apenas no período de pré-florescimento, é necessário o uso de irrigação complementar com 200 mm para induzir ao máximo florescimento e máximo rendimento de flavonóides por hectare.
42

Efeito de diferentes lâminas de irrigação na produção de óleo essencial do manjericão / Effect of different water depths in the basil oil production

Pravuschi, Paulo Roberto 28 May 2008 (has links)
Made available in DSpace on 2016-01-26T18:56:34Z (GMT). No. of bitstreams: 1 Dissertaca Paulo.pdf: 254511 bytes, checksum: c2a84e6eed7079ddc23e53dc978a94f9 (MD5) Previous issue date: 2008-05-28 / The purpose of this experiment was to analyze five irrigation water depth effect on the basil production. The basil is a plant very used as spice to food preparation. The water depths had been based in the class A pan evaporation (CPE): 0% CPE; 50% CPE; 75% CPE; 100% CPE, and 150% CPE. The analyzed variables were dry weight for leaves and flowers; content of essential oil and dry mass and length of root zone. It was calculated the essential oil yield and net return. The experiment was carried out in President Prudente, SP, Brazil, from March to October 2007. The third harvest was possible only under irrigation. The daily excessive water depth was detrimental to the plant development. The 100% CPE water depth showed maximum dry mass productivity (4,248.67 kg ha-1), maximum essential oil yield (58.26 kg ha-1) with the net annual profit of R$ 2,543.82 ha-1. / O objetivo deste experimento foi analisar o efeito de cinco lâminas de irrigação na produção do manjericão, planta muito usada como tempero na preparação de alimentos. As lâminas foram baseadas na evaporação do tanque classe A (ECA) sendo: 0% ECA; 50% ECA; 75% ECA; 100% ECA e 150% ECA. As variáveis analisadas foram a matéria seca das folhas e inflorescências, teor de óleo essencial e massa seca e comprimento de raízes. Foram calculadas a produtividade de óleo essencial e a receita líquida. O experimento foi instalado em Presidente Prudente-SP no período de março a outubro de 2007. A terceira colheita só foi viável utilizando irrigação. A irrigação excessiva diária prejudicou o desenvolvimento da planta. A lâmina de irrigação equivalente a 100% ECA apresentou a máxima produtividade de massa seca (4.248,67 kg ha-1), a máxima produtividade de óleo essencial (58,26 kg ha-1) com a receita líquida anual de R$ 2.543,82 ha-1.
43

Teor e rendimento de flavonóides em calêndula (Calendula officinalis L.) cultivada com diferentes lâminas de irrigação / ABSTRACT Content and yield of flavonoids in marigold plant (Calendula officinalis L.) under different irrigation depths

Bortolo, Daniela Perez Guerrero 24 September 2008 (has links)
Made available in DSpace on 2016-07-18T17:51:03Z (GMT). No. of bitstreams: 1 Dissertacao Daniela.pdf: 200686 bytes, checksum: 738c24570a7f86211f674f2c744f2487 (MD5) Previous issue date: 2008-09-24 / Calendula officinalis L. could be used as ornamental, culinary and therapeutic. The inflorescence is used as healing and anti-inflammatory. This experiment analyzed the effect of four different irrigations depth under field conditions in the production of flavonoids in the marigold plant (Calendula officinalis L.). The water depths were estimated upon the class A pan evaporation (CPE): 0, 50, 100 and 150% CPE. The depths were applied since of the beginning flowering until the end of culture cycle. There were no statistical differences in the flavonoids content. The higher dry weight flowers and flavonoids yield were obtained with the treatment without irrigation. The higher content of proline was found stressing the overwatering treatment. The accumulated water deficit for the treatment without irrigation signalized possible death by water deficit. With the precipitation occurrence in the pre-flowering, the plant, originated in the Mediterranean Basin, answered with abundant flourishment, in mass and in number of flowers. For Presidente Prudente region (São Paulo State, Brazil), if did not occur water replacement only in the pre-flowering, it will be necessary supplementary irrigation of 200 mm to induce the maximum flowering and yield per hectare of flavonoids. / A Calendula officinalis L. apresenta uso ornamental, culinário e terapêutico. A inflorescência é usada com ação cicatrizante e antiinflamatória. O experimento analisou o efeito de quatro lâminas de irrigação em condições de campo, na produção de flavonóides em calêndula. As lâminas baseadas na evaporação do Tanque Classe A (ECA) foram: 0, 50, 100 e 150% ECA; sendo aplicadas desde o início do florescimento até o final do ciclo da cultura. O teor de flavonóides não apresentou diferenças estatísticas. Os maiores valores de matéria seca de flores e rendimento de flavonóides foram obtidos no tratamento sem irrigação. O teor de prolina foi maior para o tratamento com estresse por excesso hídrico. A deficiência hídrica acumulada para o tratamento sem irrigação sinalizou uma possível morte por deficiência hídrica. Com a ocorrência da precipitação no período de pré-florescimento, a planta, originária do Mediterrâneo, respondeu com um florescimento abundante em massa e em número de flores. Assim, para região de Presidente Prudente São Paulo, caso não ocorra a reposição hídrica do solo apenas no período de pré-florescimento, é necessário o uso de irrigação complementar com 200 mm para induzir ao máximo florescimento e máximo rendimento de flavonóides por hectare.
44

Efeito de diferentes lâminas de irrigação na produção de óleo essencial do manjericão / Effect of different water depths in the basil oil production

Pravuschi, Paulo Roberto 28 May 2008 (has links)
Made available in DSpace on 2016-07-18T17:51:15Z (GMT). No. of bitstreams: 1 Dissertaca Paulo.pdf: 254511 bytes, checksum: c2a84e6eed7079ddc23e53dc978a94f9 (MD5) Previous issue date: 2008-05-28 / The purpose of this experiment was to analyze five irrigation water depth effect on the basil production. The basil is a plant very used as spice to food preparation. The water depths had been based in the class A pan evaporation (CPE): 0% CPE; 50% CPE; 75% CPE; 100% CPE, and 150% CPE. The analyzed variables were dry weight for leaves and flowers; content of essential oil and dry mass and length of root zone. It was calculated the essential oil yield and net return. The experiment was carried out in President Prudente, SP, Brazil, from March to October 2007. The third harvest was possible only under irrigation. The daily excessive water depth was detrimental to the plant development. The 100% CPE water depth showed maximum dry mass productivity (4,248.67 kg ha-1), maximum essential oil yield (58.26 kg ha-1) with the net annual profit of R$ 2,543.82 ha-1. / O objetivo deste experimento foi analisar o efeito de cinco lâminas de irrigação na produção do manjericão, planta muito usada como tempero na preparação de alimentos. As lâminas foram baseadas na evaporação do tanque classe A (ECA) sendo: 0% ECA; 50% ECA; 75% ECA; 100% ECA e 150% ECA. As variáveis analisadas foram a matéria seca das folhas e inflorescências, teor de óleo essencial e massa seca e comprimento de raízes. Foram calculadas a produtividade de óleo essencial e a receita líquida. O experimento foi instalado em Presidente Prudente-SP no período de março a outubro de 2007. A terceira colheita só foi viável utilizando irrigação. A irrigação excessiva diária prejudicou o desenvolvimento da planta. A lâmina de irrigação equivalente a 100% ECA apresentou a máxima produtividade de massa seca (4.248,67 kg ha-1), a máxima produtividade de óleo essencial (58,26 kg ha-1) com a receita líquida anual de R$ 2.543,82 ha-1.
45

Advancing Water Security and Environmental Sustainability Through Evaluation of Water Use From the Field to State-Wide Scale

Sangha, Laljeet Singh 17 January 2023 (has links)
The United States (US) has experienced a surge in water shortages and droughts in recent times. Water shortages can result from population growth, climate change, inadequate water management policies, and the improper use of available technologies. The existing data and research on water use associated with water management policy structures are limited. Many states in the US follow strict regulations on water discharge into streams to enforce water quality standards; however, water withdrawal restrictions from streams are limited and inadequate in terms of water management at times of low flow. In states such as Virginia (VA), the Virginia Department of Environmental Quality (VDEQ) requires a Virginia Water Protection (VWP) permit for all water withdrawals from VA's surface waters. However, under certain provisions of VWP regulations, users are exempted from having a permit. Such permit exemptions exist in many states and present a severe challenge to water supply management. Chapter 2 compares the impact of permit exemptions on surface water availability and drought flows and compares these impacts to the relatively well-studied risks presented by dry climate change and demand growth in Virginia (VA). It was observed that in some regions, the impacts under the exempt user scenario were higher than those under the dry climate change scenario. In addition, water supply managers and government agencies use user-reported water withdrawal data to develop water management programs. Irrigated agriculture is the largest source of water consumption in the US. However, water-reporting regulations exempt users from withdrawing water for irrigation under a certain threshold. Moreover, as water is not metered, users often do not report their irrigation water use, resulting in considerable uncertainty about the impacts of irrigation withdrawals, which could potentially impact other water users, lead to water shortages or conflicts, and negatively impact stream ecology. Chapter 3 focuses on developing a novel methodology for quantifying unreported irrigation water withdrawals using publicly available USDA-Census and USDA-IWMS datasets. This method was used to evaluate the unreported water withdrawals in the VA. Finally, water use practices at the field level intersect with other environmental issues at a larger scale. For example, irrigation practices can influence nutrient uptake and transport at the field level. Insufficient water for irrigation, especially during critical growth stages, results in yield and economic losses and reduces agricultural productivity. However, excessive irrigation can lead to wasted water and energy as well as runoff and leaching of nutrients and agricultural chemicals. Therefore, the adoption of technological advancements at the field scale can reduce the amount of water needed to fulfill the needs while mitigating any nutrient impacts on the soil due to the excessive use of water. This is highly important when fertilizer prices are always high. Chapter 4 focuses on quantifying the impact of the use of short-term weather forecast data in irrigation scheduling on nutrient and water use efficiency in humid climates: experimental results for corn and cotton. It was found that irrigation scheduling using short-term weather forecast data is helpful for improving the nutrient and water use efficiency of corn. For cotton, nutrient and water use efficiency are highly influenced by irrigation and precipitation with respect to the growth stage. / Doctor of Philosophy / Water shortages in the US have increased in recent times owing to climate change. Water demand is expected to increase in the future due to population growth and economic development in certain regions. Water supply planning is significantly influenced by water policy regulations. Water withdrawal regulations mandate a water withdrawal permit for making withdrawals in many states across the US. However, due to provisions in the same water regulations, certain users are exempt from taking a water withdrawal permit. One example of such users is grandfathered users who had a water withdrawal permit before July 1, 1989, in Virginia. Such exemptions are a severe challenge to the management of water supply, as exempt withdrawal amounts are generally high. We studied the impacts of these exempt users on VA's water resources of VA and compared them with the impacts of dry climate change and 2040 demand growth in Chapter 2. The results indicate that the impact of exempt users is higher than that of climate change in some regions across VA. Additionally, water-reporting regulations require users to report irrigation water withdrawals. However, users below the reporting threshold were excluded from reporting. Some users might underreport or do not comply with the water withdrawal regulations. These user-reported data are often used in developing water management plans, which may become ineffective owing to incomplete water use data. Chapter 3 focuses on the development of a data-based approach for quantifying unreported irrigation water withdrawals. This method would be transferable to any other state across the US. We compared the estimated irrigation withdrawals with reported irrigation withdrawals across the VA and generated unreported withdrawals at the county level in the VA. Finally, at the field level, irrigation can highly influence the nutrient uptake of plants. Excess irrigation may result in the removal of nutrients below the roots of the plant or may be removed by surface runoff, making it unavailable for plant uptake. Along with the economic impacts of unused fertilizer and loss in yield, unused nutrients may impact the environment and water bodies. Chapter 4 focuses on the impact of short-term weather forecast data on the irrigation scheduling of corn and cotton in humid climates. We found that weather-informed irrigation is helpful in increasing the nutrient and water use efficiency of corn. For cotton, the results were highly affected by precipitation and irrigation with respect to the growth stage of cotton.
46

Evaluation of surface energy balance models for mapping evapotranspiration using very high resolution airborne remote sensing data

Paul, George January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / P.V. Vara Prasad / Agriculture is the largest (90%) consumer of all fresh water in the world. The consumptive use of water by vegetation represented by the process evapotranspiration (ET) has a vital role in the dynamics of water, carbon and energy fluxes of the biosphere. Consequently, mapping ET is essential for making water a sustainable resource and also for monitoring ecosystem response to water stress and changing climate. Over the past three decades, numerous thermal remote sensing based ET mapping algorithms were developed and these have brought a significant theoretical and technical advancement in the spatial modeling of ET. Though these algorithms provided a robust, economical, and efficient tool for ET estimations at field and regional scales, yet the uncertainties in flux estimations were large, making evaluation a difficult task. The main objective of this study was to evaluate and improve the performance of widely used remote sensing based energy balance models, namely: the Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution and with Internalized Calibration (METRIC), and Surface Energy Balance System (SEBS). Data used in this study was collected as part of a multi-disciplinary and multi-institutional field campaign BEAREX (Bushland Evapotranspiration and Agricultural Remote Sensing Experiment) that was conducted during 2007 and 2008 summer cropping seasons at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas. Seventeen high resolution remote sensing images taken from multispectral sensors onboard aircraft and field measurements of the agro-meteorological variables from the campaign were used for model evaluation and improvement. Overall relative error measured in terms of mean absolute percent difference (MAPD) for instantaneous ET (mm h[superscript]-[superscript]1) were 22.7%, 23.2%, and 12.6% for SEBAL, METRIC, and SEBS, respectively. SEBAL and METRIC performances for irrigated fields representing higher ET with limited or no water stress and complete ground cover surfaces were markedly better than that for dryland fields representing lesser ET and greater soil water deficits with sparser vegetation cover. SEBS algorithm performed equally well for both irrigated and dryland conditions but required accurate air temperature data. Overall, this study provides new insights into the performance of three widely used thermal remote sensing based algorithms for estimating ET and proposed modifications to improve the accuracy of estimated ET for efficient management of water resources.
47

Impact on yield and water productivity of wheat by access to irrigation scheduling technologies in Koga Irrigation Scheme, Ethiopia / Utvärdering av hur tillgång till teknologier för bevattningsplanering påverkar skörd och vattenproduktivitet för vete i Koga bevattningssystem, Etiopien

Svedberg, Elin January 2019 (has links)
Improving water use efficiency is included in the Sustainable Development Goals of the United Nations. Ethiopia is a developing country struggling with food production as well as water scarcity. This study presents the results of a statistical analysis of changes in water productivity (i.e. yield versus water usage), wheat yield and irrigation amount by implementation of irrigation scheduling in Koga Irrigation Scheme, north-west Ethiopia. Highest water usage (570 mm), lowest water productivity (0.5 kg m-3) and lowest yield (2800 kg ha-1) were obtained for the control group (i.e. traditional irrigation scheduling, based on experience). All groups which implemented some irrigation scheduling displayed higher water productivity than the control group. The highest water productivity and yield was achieved with a soil moisture sensor (Chameleon) technology, with increases of 58 % and 32 % with respect to the control group, respectively. Nitrogen had a positive effect on both yield and water productivity, however, the interaction effects between applied nitrogen and implemented irrigation scheduling were considered insignificant. This study is concluding that implementation of irrigation scheduling should be a successful approach for improving yield as well as water productivity in Koga. / En förbättrad effektivitet i vattenanvändningen ingår i Förenta nationernas Globala mål för hållbar utveckling. Etiopien är ett utvecklingsland med utmaningar i såväl matproduktion som vattenbrist. Denna studie presenterar resultaten av en statistisk analys av förändringar i vattenproduktivitet (dvs skörd per vattenmängd), skörd och bevattningmängd genom implementering av verktyg för bevattningsplanering i Koga bevattningsområde, nordvästra Etiopien. Högsta vattenförbrukning (570 mm), lägsta vattenproduktivitet (0,5 kg m-3) och lägsta skörd (2800 kg ha-1) erhölls för kontrollgruppen. Alla grupper som infört någon typ av bevattningsplanering visade högre vattenproduktivitet än kontrollgruppen (dvs traditionell bevattningsplanering baserad på erfarenhet). Den högsta vattenproduktiviteten och skörden uppnåddes med en vattenfuktsmätare (Chameleon), med ökningar på 58 % respektive 32 % jämfört med kontrollgruppen. Kväve hade en positiv effekt på både skörd och vattenproduktivitet, men interaktionseffekterna mellan kväve och de implementerade bevattningsplaneringarna ansågs försumbara. Denna studie drar slutsatsen att införandet av någon typ av bevattningsplanering bör vara ett framgångsrikt tillvägagångssätt för att förbättra skörd samt vattenproduktivitet i Koga. / “Using Remote Sensing in support of solutions to reduce agricultural water productivity gaps” (Capacity development for increasing water productivity) (GCP/INT/229/NET)
48

Water relations in red and white clover seed crops

Oliva, Ruben N. 09 September 1992 (has links)
Both red (Trifolium pratense L.) and white (Trifolium repens L.) clover seed yields can be highly variable and low in western Oregon. The objectives of this study were to: i) determine crop water requirements and supplemental irrigation timing, and ii) quantify the effects of soil and water status on inflorescence production, seed yield and seed yield components for red and white clover seed crops. In each species, five supplemental irrigation treatments were applied in 1990 and 1991 to first and second year seed crops grown on a Woodburn silt loam (fine-silty, mixed, mesic Aquultic Argixeroll) near Corvallis, OR. Non-irrigated controls were also maintained. In red clover, increased plant water stress reduced the duration of the season-long bud and flower production, stem length, potential floral capacity (PFC), and seed yield (SY). Root rot index (RRI) increased with increasing levels of plant water stress, indicating that supplemental water applications reduced second-year root rot severity. The reduction in SY from increasing plant water stress was primarily caused by a decrease in floral fertility, and less conclusively by reductions in inflorescence number per unit area. One irrigation to fill the soil active profile during peak flowering provided adequate water to maintain efficient seed production. In white clover, SY was maximum in 1990 when water application was delayed until 68% of the available soil-water was used by the crop which maintained an even flush of flowers and restricted vegetative growth. In 1991, all irrigation treatments yielded the same or less than the non-watered control. This was due to the excessive vegetative growth from stolons that had grown between the planted rows the previous and present crop year. In both years excessive amounts of irrigation water favored profuse vegetative growth and reduced SY. Inflorescence density was increased by constraining soil-water in 1990 and was the yield component that most affected SY both years. Crop water stress index (CWSI) was a useful indicator of plant stress status and can be used to schedule irrigations in red and white clovers grown for seed under typical climatic conditions of western Oregon. / Graduation date: 1993
49

Braškių vandens poreikio tyrimai Lietuvos Vidurio zonoje / Strawberry water requirements in Middle Lithuania

Taparauskienė, Laima 09 February 2006 (has links)
Restoration of Lithuanian independence, land reform, radically changed farming structure and strawberry growing potential has conditioned an increase of modern strawberry plantation. Irrigation is a rather important precondition for the commercial cultivation of fruit and berries in Lithuania. The new farm structure requires new, mainly small-scale irrigation systems. Strawberry water consumption and the soil water dynamics during strawberry growing period stated performing pilot research and additional yield which had been got because of the irrigation influence allows to measure optimal irrigation regime of the strawberry based on research. The aim of the work was to investigate dynamics of strawberry evapotranspiration in the Middle Lithuania and in the course of experiments, with respect to development peculiarities and productivity, to determine optimal irrigation regime for the strawberry grown in loamy soils. In the summary is presented strawberry evapotranspiration results maintaining optimal soil moisture conditions with irrigation; analysis of reference evapotranspiration methods; determination of their interaction degree and evaluation of the possibilities to introduce reference evapotranspiration models in calculation of the evapotranspiration of strawberries; quantitative evaluation of the influence of meteorological factors on the amount of the water consumed by strawberries and analysis of strawberry evapotranspiration calculation methods; evaluation of soil... [to full text]
50

Resposta da cultura de melão a diferentes intensidades e frequências de irrigação em Porto Nacional - TO

Reis, Clerson Dalvani January 2010 (has links)
O Estado do Tocantins vem a cada dia recebendo mais investimentos públicos e privados para desenvolvimento da agricultura irrigada. Esse crescimento não está sendo acompanhado com o desenvolvimento suficiente de pesquisas e difusão de técnicas aplicáveis para irrigação nessa região. Esse trabalho é um experimento no município de Porto Nacional, região central do Estado do Tocantins, com o cultivo de meloeiros irrigados sob diferentes intensidades e freqüências. Foram aplicadas três lâminas diárias: uma calculada cientificamente, outra aplicando métodos usuais praticados na região e outra com métodos usuais menos 10%. Todas as doses foram aplicadas de duas maneiras: aplicação diária única da dose e aplicação dessa mesma dose fracionada em duas aplicações ao dia. O experimento demonstrou que a quantidade de água aplicada tradicionalmente pelos irrigantes da região é aproximadamente 75 % e 95% maior do que a calculada pelo método de Penman-Monteith. Esta aplicação tradicional, em comparação com a dose determinada a partir do cálculo da evapotranspiração, não melhora os resultados obtidos nas lavouras quanto a: produtividade, brix, comprimento dos frutos, perímetro dos frutos, peso dos frutos, espessura da polpa e número de frutos descartados e que o fracionamento da dose diária em duas aplicações, uma pela manhã e outra à tarde, melhora a produtividade e aumenta a espessura da polpa, ambas características de interesse geral de produtores. / The state of Tocantins is every day getting more public and private investments for development of irrigated agriculture. This growth is not accompanied with sufficient development of researching and dissemination of technical requirements for irrigation in this region. This work is an experiment in Porto Nacional, the central region of Tocantins State, with the irrigated cultivation of melon under different intensities and frequencies. We applied three doses daily: a scientifically calculated, another applying the usual methods applied in the region and the other with the usual methods 10%. All doses were applied in two ways: application of a single daily dose and application of the same dose split in two applications a day. The experiment showed that the amount of water applied traditionally by irrigators in the region is approximately 75% and 95% higher than that calculated by the Penman-Monteith. This traditional application, compared with the dose determined from the calculation of evapotranspiration, does not improve the results in crops as the yield, brix, fruit length, fruit girth, fruit weight, flesh thickness and fruit number discarded and the fractioning of the daily dose into two applications, one in the morning and afternoon, improves productivity and increases the thickness of the pulp, both features of interest of farmers.

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