scholarly journals EFEITO DE DIFERENTES LÂMINAS DE IRRIGAÇÃO NAS VARIÁVEIS DE DESENVOLVIMENTO E PRODUÇÃO DO CAFEEIRO IRRIGADO POR PIVÔ CENTRAL

Irriga ◽  
2015 ◽  
Vol 20 (3) ◽  
pp. 528-543 ◽  
Author(s):  
Marcelo Rossi Vicente ◽  
Everardo Chartuni Mantovani ◽  
ANDRÉ LUÍS TEIXEIRA FERNANDES ◽  
FÁBIO TEIXEIRA DELAZARI ◽  
EDMILSON MARQUES FIGUEREDO
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Coffea Arabica ◽  
Block Design ◽  
Irrigation Management ◽  
Randomized Block Design ◽  
Center Pivot ◽  
Irrigation Depth ◽  
Use Efficiency ◽  
Level Of Significance

EFEITO DE DIFERENTES LÂMINAS DE IRRIGAÇÃO NAS VARIÁVEIS DE DESENVOLVIMENTO E PRODUÇÃO DO CAFEEIRO IRRIGADO POR PIVÔ CENTRAL  MARCELO ROSSI VICENTE1; EVERARDO CHARTUNI MANTOVANI2; ANDRÉ LUÍS TEIXEIRA FERNANDES3; FÁBIO TEIXEIRA DELAZARI4 E EDMILSON MARQUES FIGUEREDO5 1 Instituto Federal do Norte de Minas Gerais, Salinas, MG, [email protected] Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, Viçosa, MG, [email protected] Universidade de Uberaba, Uberaba, MG, Fábio Teixeira Delazari, [email protected] Departamento de Fitotecnia, Universidade Federal de Viçosa, Viçosa, MG, [email protected] Bahia Farm Show, Luís Eduardo Magalhães, BA, [email protected]  1      RESUMO O presente trabalho foi conduzido com objetivo de avaliar o efeito de diferentes lâminas de irrigação nas variáveis de produção, estádios maturação de frutos e eficiência no uso da água pela cultura do cafeeiro irrigado por pivô central equipado com emissores LEPA, na região Oeste da Bahia. Realizou-se o trabalho na fazenda Café do Rio Branco, localizada em Barreiras - BA em cafeeiros adultos da variedade Catuaí IAC 144. O experimento obedeceu ao delineamento de blocos casualizados, composto de cinco tratamentos correspondentes à 70, 85, 100, 125 e 150% da lâmina de irrigação determinada pelo software Irriplus. As produtividades, os estádios de maturação dos frutos e eficiência no uso da água do cafeeiro foram submetidos à análise de variância e regressão, em que os modelos foram escolhidos baseados na significância dos coeficientes de regressão utilizando-se o teste t de 1 a 10% de probabilidade. Diante dos resultados obtidos, pode-se concluir que, a produtividade da cultura do café foi expressivamente dependente da lâmina de água aplicada, sendo que a maior produtividade (60 sc ha-1) foi alcançada com a lâmina de irrigação acumulada de 661 mm ano-1, correspondente à 96% da lâmina de irrigação determinada pelo software Irriplus. A lâmina que proporcionou a máxima porcentagem de frutos cereja (44,1%) foi de 723 mm ano-1 (105%). A lâmina que proporcionou a maior eficiência no uso da água foi de 480 mm ano-1 (70%). Palavras-Chave: Coffea arabica, manejo da irrigação, emissor LEPA, uso eficiente da água.  VICENTE, M. R.; MANTOVANI, E. M.; FERNANDES, A. L. T.; DELAZARI, F. T.; FIGUEREDO, E. M.EFFECTS OF DIFFERENT LEVELS OF IRRIGATION DEPTHS   ON GROWTH AND PRODUCTION VARIABLES OF COFFEE UNDER CENTER PIVOT  IRRIGATION     2        ABSTRACT This study aimed to evaluate the effect of different irrigation depths on yield, ripening stages and water use efficiency by the   coffee crop irrigated by center pivot with LEPA emitters in western Bahia. The experiment was carried out at the Café Rio Branco farm, in Barreiras city, Bahia state, using  adult coffee trees of cv. Catuaí IAC 144. A completely randomized block design was used with five treatments consisting of 70, 85, 100, 125 and 150 % of ETc, determined by the Irriplus software.  Data of yield, fruit ripening stage and water use efficiency were evaluated   using analyses of variance  and regression. Models were chosen based on level of significance of   regression coefficients using the Student´s t-test, 1 to  10% probability.  Based on the results,  coffee crop yield was highly dependent on  the water depth applied. The highest yield (3.6 ton/ha) was achieved  using accumulated irrigation depth of 661 mm year -1 (96 % of Etc).  Water depths of   723 mm year-1 (105 %) and 480 mm year-1 (70% ETc)  provided the highest percentage of cherry fruit (44.1%) and the highest water use efficiency, respectively. Keywords: Coffea arábica, irrigation management, LEPA emitter, water use efficiency.

scholarly journals Response of bell pepper crop subjected to irrigation depths calculated by different methodologies

2018 ◽  
Vol 22 (1) ◽  
pp. 45-50
Author(s):  
Gustavo H. da Silva ◽  
Mariane G. Ferreira ◽  
Silvio B. Pereira ◽  
Fábio T. Delazari ◽  
Derly J. H. da Silva
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Block Design ◽  
Irrigation Management ◽  
Fruit Production ◽  
Accurate Estimation ◽  
Randomized Block Design ◽  
Irrigation Depth ◽  
Growth Production ◽  
Use Efficiency

ABSTRACT Water must be supplied to a crop in the proper amount and in a timely manner. Vegetables require a good water availability in soil during their entire cycle. Thus, it is very important the implementation of an irrigation management and accurate estimation of water requirement. The objective of this work was to evaluate the effect of five irrigation depths estimated by the dual-Kc and single-Kc methodologies on the characteristics of growth, production and water use efficiency in the pepper crop. A randomized block design was adopted in a split plot arrangement. The effect of five irrigation depths (50, 75, 100, 125 and 150% of crop evapotranspiration - ETc) was evaluated in the plots, and the methodologies were evaluated in the subplots. It was evaluated the root dry matter, total fruit production, leaf temperature, number of aborted flowers and water use efficiency. The interaction between both effects was not significant for any of the variables. The effect of methodology was observed only on the number of aborted flowers. The effect of the irrigation depths was significant on all variables. The irrigation depths that lead to the best agronomic characteristics were superior to 100% of ETc. The ratio between the irrigation depths estimated by single-Kc and dual-Kc methodologies was 1.14. Single-Kc methodology and irrigation depth of 143% ETc were more suitable for the horticulturist. The most efficient irrigation depth in the use of water was 105% ETc.

scholarly journals Precocity, yield and water-use efficiency of banana plants under planting densities and irrigation depths, in semiarid region

2019 ◽  
Vol 49 ◽  
Author(s):  
Marcelo Rocha dos Santos ◽  
Sérgio Luiz Rodrigues Donato ◽  
Diogo Barreto Magalhães ◽  
Manoel Pereira Cotrim
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Block Design ◽  
Planting Density ◽  
Semiarid Region ◽  
Randomized Block Design ◽  
Brazilian Semiarid ◽  
Split Plot ◽  
Irrigation Depth ◽  
Use Efficiency

ABSTRACT Banana is a crop of major importance for the Brazilian semiarid region. However, because of the low availability and irregularities of the rainfall in this area, it is necessary to combine techniques that allow a higher water-use efficiency. This study aimed to evaluate the influence of different combinations of irrigation depths and planting densities on the precocity, yield and water-use efficiency of BRS Platina banana plants, in the semiarid region of the Bahia state, Brazil. A randomized block design with four replicates was used, in a split-plot arrangement. Irrigation depths of 55 %, 70 %, 85 % and 100 % of the crop evapotranspiration (ETc) were assigned to the plot, and the planting densities of 1,600 plants ha-1, 2,000 plants ha-1, 2,666 plants ha-1 and 3,333 plants ha-1 to the split-plot. The hands weight and number of fruits decreased in a linear way with the increase in the planting density (1,600 plants ha-1 to 3,333 plants ha-1) from 10.89 kg to 9.49 kg and from 97.16 to 89.86, respectively; whereas the hands yield (15.5 t ha-1 to 25.79 t ha-1) and the harvest period (442 to 455 days) increased. The number of fruits increased linearly from 89.46 to 98.08 with the irrigation depth of 55 % to 100 % of the ETc. The yield and water-use efficiency increased linearly as the planting density increased (1,600 plants ha-1 to 3,333 plants ha-1) from 5.14 to 8.60, while the water-use efficiency decreased with the irrigation depth from 7.97 to 5.50, conidering 55 % to 100 % of the ETc. It is possible to obtain higher yields and a higher water-use efficiency by using a higher planting density and irrigation levels below 100 % of the ETc.

scholarly journals EFFECT OF DIFFERENT IRRIGATION DEPTH ADJUSTMENT METHODS ON MAIZE YIELD COMPONENTS, GRAIN YIELD AND WATER USE EFFICIENCY

Irriga ◽  
2018 ◽  
Vol 23 (3) ◽  
pp. 454-466
Author(s):  
Leonardo Chechi ◽  
Luan Junior Kuhn ◽  
Vanderléia Fortuna ◽  
Patricia Mara De Almeida ◽  
Maurício Albertoni Scariot ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Yield Components ◽  
Block Design ◽  
Maize Yield ◽  
Irrigation Depth ◽  
Moisture Equivalent ◽  
Use Efficiency

As the water stress is one of the main causes for the low maize yield in Brazil, this study aimed to evaluate the yield components, grain yield and the water use efficiency of maize crop submitted to different methods of irrigation depth adjustment and validate the “Lâmina” spreadsheet to recommend irrigation depth in this crop. The treatments applied were: non-use of irrigation (control); irrigation depth adjustment provided by” Lâmina” spreadsheet (Lâmina); soil moisture equivalent to actual capacity of water in the soil at 55% of the total soil water capacity (55% RWC); and soil moisture equivalent to 100% of the field capacity (100% FC). The experimental design was a randomized block design with four replications, each experimental unit consists of a plot 3 meters wide and 3 meters long. The variables analyzed were total water applied, dry matter, ears per plant, kernel rows per ear, kernels per row, kernels per ear, one thousand kernels weight, grain yield and water use efficiency. Grain yields were similar between irrigated treatments, showing significant differences compared to the control. The Lâmina and 55% RWC showed the best results for water use efficiency and yield components. The Lâmina treatment used the least amount of water, with high yields, contributing to the rational water use in irrigated agricultural systems.

scholarly journals Center pivot irrigation management in maize hybrids and the incidence of stalk rot

2020 ◽  
Vol 24 (12) ◽  
pp. 840-846
Author(s):  
Irineu E. Kühn ◽  
Mayara F. Cotrim ◽  
Ricardo Gava ◽  
Rita de C. F. Alvarez ◽  
Job T. de Oliveira ◽  
...  
Keyword(s):  
Block Design ◽  
Irrigation Management ◽  
Management Strategies ◽  
Irrigation Frequency ◽  
Maize Hybrids ◽  
Stalk Rot ◽  
Randomized Block Design ◽  
Center Pivot ◽  
Irrigation Depth ◽  
The One

ABSTRACT This study aimed to verify the incidence of Fusarium spp. in commercial maize hybrids and irrigation management strategies utilizing center pivot systems. The experiment was carried out during the second season in a randomized block design with a split-plot arrangement with five maize hybrids (2B810, MG580, AS1633, DKB290, and AG8544). The plots were irrigated with five frequencies (1, 2, 3, 4, and 5 days) in one experiment, and five water depths (at 25, 50, 75, 100, and 125% of crop evapotranspiration) in another experiment. Plant height, ear insertion height, moisture at harvest time, yield, and incidence of stalk rot were evaluated. Neither irrigation frequency nor irrigation depth influenced the incidence of disease. The one-day irrigation frequency provided the highest yield for maize hybrids. Hybrid 2B810 showed the highest yield and the lowest incidence of the disease.

scholarly journals Biomass allocation and water use efficiency in fertigated sweet pepper

2012 ◽  
Vol 32 (2) ◽  
pp. 315-325 ◽  
Author(s):  
Francimar da S. Albuquerque ◽  
Ênio F. de F. e Silva ◽  
Marcus F. F. N. Nunes ◽  
Amanda E. R. de Souza
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Biomass Allocation ◽  
Irrigation Management ◽  
Sweet Pepper ◽  
Crop Evapotranspiration ◽  
Plant Life ◽  
Dry Biomass ◽  
Irrigation Depth ◽  
Use Efficiency

The use of productivity information and efficiency of water use is important for the economic analysis of production and irrigation management, and also helps the economy of water use, which is essential to plant life. The objective of this study was to evaluate the biomass allocation, the water use efficiency and water content in fruits of sweet pepper cropped under the influence of irrigation blades and potassium doses. The statistic design was a completely randomized factorial scheme (5 x 2) and four replications, with five irrigation blades (80; 90; 100; 110 and 120% of crop evapotranspiration) and two levels of potassium (80 and 120 kg K2O ha-1 ), applied according to phenological phase, through a system of drip irrigation with self-compensated drippers, installed in a battery of 40 drainage lysimeters cultivated with sweet pepper (Maximos F1), at Federal Rural University of Pernambuco (UFRPE), Recife, state of Pernambuco, Brazil. The dry biomass production of sweet pepper was influenced by fertigation regimes; when it was set the lowest dose, estimates of the efficiency of water use and moisture in the fruit occurred with the use of irrigation depth of 97 and 95% of ETc, respectively.

scholarly journals Use of selenium to increase antioxidant activity and water use efficiency in arugula (Eruca vesicaria ssp. Sativa) exposed to drought stress

2020 ◽  
Vol 9 (12) ◽  
pp. e3291210670
Author(s):  
Danielle Paula de Oliveira Mangarotti ◽  
Roberto Rezende ◽  
Reni Saath ◽  
Tiago Luan Hachmann ◽  
Paula Toshimi Matumoto-Pintro ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Drought Stress ◽  
Water Use Efficiency ◽  
Water Use ◽  
Block Design ◽  
Oxygen Species ◽  
Randomized Block Design ◽  
Small Doses ◽  
Growth Respiration ◽  
Use Efficiency

Environmental stress can directly or indirectly affect the formation of reactive oxygen species. Oxidative stress damages cell constituents such as carbohydrates, lipids, nucleic acids and proteins, reducing plant growth, respiration and photosynthesis. In recent decades, evidence has shown that small doses of selenium act as an antioxidant and plant biostimulant, promoting growth and improving resistance to abiotic stress such as drought. As such, the aim of this study was to assess the effect of selenium foliar feeding (0, 150 and 300 ppm) on the antioxidant activity, water use efficiency and yield traits of arugula grown with and without drought stress (50% and 100% ETc) in a protected environment. A randomized block design was used, with a 2x3 factorial scheme and four repetitions. Antioxidant activity increased in treatments with 150 ppm of fertilizer and exposure to drought stress. Plants in these treatments obtained higher water use efficiency, yield and leaf area values than those not submitted to drought stress.

Assessing yield and water use efficiency of Capsicum annuum L. cultivated in a greenhouse under different irrigation strategies

2021 ◽  
Author(s):  
Ceres Duarte Guedes Cabral de Almeida ◽  
Leandro Candido Gordin ◽  
Alexsandro Cláudio dos Santos Almeida ◽  
José Amilton Santos Júnior ◽  
Brivaldo Gomes de Almeida ◽  
...  
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Irrigation Management ◽  
Water Requirement ◽  
The Other ◽  
Crop Water ◽  
Evaporative Demand ◽  
Irrigation Depth ◽  
Use Efficiency ◽  
Commercial Yield

<p>Several methodologies and techniques are available for irrigation management in protected environments. Despite the cultivation of vegetables in the greenhouse is largely present in the northeastern region of Brazil, not many research has been aimed at supporting growers for accurate irrigation management.</p><p>The objective of this study is to evaluate yield and irrigation water use efficiency of Capsicum crop cultivated in a greenhouse under different methods to define the daily irrigation depth, based on the soil water status and the atmospheric evaporative demand. Moreover, two different strategies to apply the estimated irrigation depths (single or double daily application) were also examined.</p><p>The experiment was carried out in a greenhouse in the Federal Rural University of Pernambuco (UFRPE), northeastern of Brazil (8° 01’ 07” S and 34° 56’ 53” W, altitude 6.50 m). Based on a completely randomized design, the experimental units were distributed according to a 4 x 2 factorial scheme with eight replications, with a total of 64 experimental units. Four methods to estimate daily irrigation water requirement were evaluated: two based on soil sensors (soil water content sensors EC-5, SWS, and tensiometers, TS), whereas the other two were based on the atmospheric evaporative demand (weighing lysimeter, WL, and Piché evaporimeter, PE). Moreover, the daily irrigation depths were applied with a single watering (at 8:00 am) or split into two applications (the half at 8:00 am and the half at 4:30 pm). The commercial yield of the examined crop was calculated through the relationship between the weight of fresh fruit and the area occupied by the plant.</p><p>The statistical analysis showed that the water use efficiency, the total water volume applied and the commercial yield of capsicum were significantly influenced by the method used to estimate crop water requirement, as well as the irrigation strategies. The total irrigation depth applied during the entire crop cycle resulted in equal to 509 mm, 678 mm, 716 mm, and 790 mm for treatments with WL, PE, SWS, and TS, respectively. The seasonal applied irrigation depths corresponded to an average daily crop water requirement ranging, according to the treatments, from 5.4 to 8.3 mm day<sup>-1</sup>; these values are consistent for the examined crop cultivated under protected conditions. The highest yields of commercial fruits were obtained in the treatments in which the highest irrigation depth (SWS and TS) was applied. On the other hand, the highest values of water use efficiency were obtained in those treatments in which the irrigation depth was defined based on SWS and WL. Splitting the estimated daily irrigation depth in two applications promoted greater commercial productivity and water use efficiency (10.73 t ha<sup>-1</sup> and 1.60 kg m<sup>-3</sup>) compared to a single application (8.14 t ha<sup>-1</sup> and 1.22 kg m<sup>-3</sup>), with an increase of both variables of about 31%. These results evidenced that splitting the daily irrigation depth is a promising strategy to increase water use efficiency for vegetable crops in protected environments.</p>

scholarly journals Water Use Efficiency, Yield and Crop Coefficient (Kc) of Groundnut crop under different Water Regimes

2017 ◽  
Vol 3 (9) ◽  
pp. 110
Author(s):  
Aruna KT
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Block Design ◽  
Crop Coefficient ◽  
Growth Stages ◽  
Water Regimes ◽  
Randomized Block Design ◽  
Significant Difference ◽  
Use Efficiency

The pot experiment was carried out during September 2015 to January 2016 at instructional farm, College of Agricultural Engineering, UAS Raichur under rain shelter to study the effect of different water regimes, (i.e. T1:100, T2:90, T3:80, T4:70, T5:60 and T6:50) per cent of water application with available moisture holding capacity on grain yield and water use efficiency. Completely Randomized block design with four replications was used in this study. The results showed that there was significant difference between the yield and (WUE) under different levels of irrigation. The total irrigation water applied were (i.e., 211.98, 243.02, 225.78, 155.09, 135.51 and 105.62 mm/plant) under different water regime treatments (100, 90, 80, 70, 60 and 50 %) of available moisture holding capacity (AMHC) respectively. Grain yield productions under different treatments were 106.25, 171.25, 127.50, 75, 55 and 40.75 g/plant/pot at 100, 90, 80, 70, 60 and 50 per cent of AMHC respectively. The results showed that water use efficiency (WUE) at different treatments were 0.50, 0.70, 0.56, 0.48, 0.41 and 0.39 g/mm for (100, 90, 80, 70, 60 and 50 %) per cent of AMHC respectively. Therefore, the 90 % of AMHC treatment (T2) is recommended for groundnut irrigation for water saving. The comparison of actual crop coefficient that obtained by water balance technic in experiment and crop coefficient (Kc) values of groundnut for different crop growth stages were selected based on the values suggested by FAO (Allen et al., 1998) are similar in the treatment of 90 % (T2) of the AMHC. Furthermore, the result showed that the treatment of 90 per cent of Available moisture holding capacity (T2) seemed to be better adapted to product a high crop yield with acceptable yield coupling with water use efficiency in this region.

scholarly journals Assessing the Water and Thermal Use Efficiencies of Groundnut (Arachis hypogaea) Grown under Different Strength of Jute Agro Textile Mulch in India

2019 ◽  
pp. 1-10
Author(s):  
Anwesha Sarkar ◽  
Argha Ghosh ◽  
P. K. Tarafdar ◽  
S. K. De
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Dry Matter ◽  
Block Design ◽  
Soil Condition ◽  
Dry Matter Accumulation ◽  
Thermal Indices ◽  
Yield Attributes ◽  
Randomized Block Design ◽  
Use Efficiency

Aims: To evaluate the effects of jute agrotextile mulches on yield and yield attributes, dry matter accumulation, water use efficiency as well as accumulated agrometeorological indices and thermal utilization of groundnut. Place and Duration of Study: The study was conducted in the experimental farm of Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India during kharif season of 2017 and 2018. Methodology: The experiment was carried in randomized block design with five treatments each of which was replicated four times Groundnut (variety J L-24) as a test crop. The treatments (T), composing different strength of jute agro textile (JAT) used as mulching material were as follows: T1: 1000 GSM JAT, T2: 800 GSM, T3: 600 GSM, T4: 400 GSM JAT and T5: farmer's practice (control) where GSM is gram per square meter. All the data regarding the yield, yield attributes, water use efficiency and thermal utilization of the crop were recorded accordingly. Results: Response of pod yield over control were 24.26 q/ha, 26.44 q/ha, 20.98 q/ha and 18.25q/ha in T1, T2, T3, T4, T5 respectively. Though all the treatments showed increment over control, the highest result was found in T2 and a further increase in strength of JAT showed a decrement in all aspects. The water use efficiency, at an average, increased by 69.12% due to the various treatments over control. Heat unit and thermal units use efficiencies were also highest in treatment T2 which showed the most accurate utilization of thermal indices. Conclusion: Therefore, among all the treatments T2 exhibited the most promising effect on improving yield and other attributes along with maintaining sustainability as it might have provided the most favourable soil condition compared to other mulches for groundnut.

scholarly journals IRRIGATED MAIZE CROP: GRAIN YIELD IN TWO SOWING SEASONS IN THE MUNICIPALITY OF TERESINA, PIAUÍ

2020 ◽  
Vol 19 ◽  
pp. 12
Author(s):  
MILTON JOSÉ CARDOSO ◽  
HÉLIO WILSON LEMOS CARVALHO ◽  
LEONARDO MELO PEREIRA ROCHA ◽  
LAURO MOREIRA GUIMARÃES ◽  
PAULO EVARISTO GUIMARÃES
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Block Design ◽  
Sprinkler Irrigation ◽  
Maize Crop ◽  
Maize Hybrids ◽  
Randomized Block Design ◽  
Use Efficiency ◽  
Sowing Season

The objective of this work was to evaluate commercial maize hybrids, under conventional sprinkler irrigation, in two sowing seasons (July and August 2017), in the municipality of Teresina, Piauí. A randomized block design was used, with two replications and 39 treatments (commercial maize hybrids). The characteristics evaluated were grain yield, water use efficiency, number of ears and number of grains per area. For the experiment with sowing done in July 2017, the average grain yield was 9.82 Mg ha-1 and the water use efficiency was 1.9 kg m-3, which are, respectively, 4.7 % and 15.8 % higher in relation to the experiment with sowing done in August 2017. Regardless of the sowing season, grain yields over 10.0 Mg ha-1 of three hybrids (LG 6418, CD 3880 PW and 2A 401 PW) stand out. The yield components, number of kernels per ear and grain mass per ear, show high values of correlation (over 0.80) with grain yield.

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