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Information on soil hydrodynamic processes assists in explaining the soil-water-plant relationship and has practical applications to irrigation management, such as the definition of soil water sensor placement. The objective of this study was to detail the hydrodynamic process in the soil root zone and to define the location for placement of soil water sensor under different configurations of trickle irrigation in banana crops. Three micro-sprinkler emitters with flow rates of 70 (T1), 53 (T2), 35 L h-1 (T3), and two drip system, one with one drip line per row of plants (T4), and another with two drip lines per row of plants (T5) were evaluated. The experiment was conducted in a randomized block design with five repetitions. Higher water extraction was found for irrigation systems with higher flow rates for all configurations of trickle irrigation systems. Soil moisture sensors in drip systems should be placed at distances of 0.75 to 0.81 m from the pseudo stem and at depths of 0.33 to 0.44 m. Under micro-sprinkler systems, soil water sensors should be placed at 0.75, 0.77 and 0.83 m from the pseudo stem towards to the emitter and at depths of 0.33, 0.48 and 0.55 m for emitter flow rates of 35, 53 and 70 L h-1, respectively. Made available in DSpace on 2021-05-21T02:20:23Z (GMT). No. of bitstreams: 1 Management-of-trickle.pdf: 778920 bytes, checksum: 056f34b0ad1401fe6c2f68b0a575a79b (MD5) Previous issue date: 2021

Selection of tolerant plants is essential to meet the challenges of food production. The objective of this study was to evaluate agronomic and physiological characteristics as indicators for the selection of water restriction-tolerant grain sorghum genotypes. The experiments were conducted in 2014, 2015 and 2016. Two trials were installed in each year, one subjected to full irrigation and the other to water restriction. In the first one, irrigation was performed periodically, at a 2-day interval, to maintain soil moisture close to field capacity. In the second one, irrigation was suspended in the pre-flowering period, keeping the restriction for 30 days. Four sorghum genotypes were used: 9503062 and 9618158 - drought sensitive (S); 9910032 and P898012 - drought tolerant (T). The experimental design was randomized blocks with four replicates. Stomatal conductance, relative chlorophyll content, photosynthetically active leaf area, plant height and yield were evaluated. Joint analysis of the experiments subjected to full irrigation and water restriction of the three years was performed. Under water restriction it was not possible to distinguish between sensitive and tolerant materials. The characteristics evaluated in this experiment did not allow a conclusive distinction between tolerant and sensitive genotypes. Made available in DSpace on 2020-08-24T04:11:52Z (GMT). No. of bitstreams: 1 Agronomic-physiological.pdf: 684693 bytes, checksum: ded501d7d6f865c92d99119df48c90d4 (MD5) Previous issue date: 2020

Objetivando subsidiar o manejo racional da cultura do limoeiro irrigado sob diferentes sistemas de irrigação e porta-enxertos, imagens Landsat 8 (L8) e dados climáticos foram usadas através do algoritmo SAFER, ao longo do ano de 2015, para a modelagem dos componentes da produtividade da água da cultura, no município de Matias Cardoso, Estado do Minas Gerais, Sudeste do Brasil. Para os sistemas de irrigação localizada, micro aspersão e gotejamento, o período de maior consumo hídrico, com a evapotranspiração real (ET) acima de 4,0 mm dia-1, foi da segunda quinzena de fevereiro à primeira quinzena de março, enquanto que para o sistema de irrigação por pivô, os máximos, com ET acima de 4,5 mm dia-1 aconteceram do final de outubro para o início de novembro. Considerando-se todas os sistemas de irrigação e porta-enxertos utilizados, a produtividade da água baseada na ET (PAET) média foi de 2,4 kg m-3. Os valores de coeficiente de cultua (Kc) variaram de acordo com as fases fenológicas consideradas na região de estudo, sendo de 1,01 e 0,97 para as duas floradas; de 1,04 e 0,80 nas duas fases de crescimento dos frutos; e de 0,88, 1,06 e de 0,72 nos três picos de colheita. Os resultados indicaram a possibilidade de economia de água no manejo de irrigação com manutenção da produtividade de limões. Made available in DSpace on 2017-12-21T23:34:08Z (GMT). No. of bitstreams: 1 4884.pdf: 3588676 bytes, checksum: 55f7390cf091b5b6fd055ddafa7f8195 (MD5) Previous issue date: 2017-12-21

The Jaíba Irrigated Perimeter is a large irrigated agriculturearea, located in the region Forest Jaíba between the SãoFrancisco and Verde Grande rivers, in the Brazilian semi-arid region. In 2014, irrigators thisthe region face losses in theinterruption of new plantings in irrigated areas due to water scarcity. The objective ofthis study is combine the modelto estimate the Monteith BIO with the SAFER algorithm in the case of obtaining ET, to analyze the dynamics of naturalvegetation and irrigated crops in water scarcity period. For application of the model are necessary data frommeteorological stations and satellite images. Were used 23satellite images of MODIS withspatial resolution of 250mand temporal 16 days, of 2014 year. For analyze the results,we used central pivots irrigation mask of Minas Geraisstate, Brazil. In areas with irrigated agriculture with central pivot, the mean values of BIO over the year 2014 were88.96 kg.ha-1.d-1. The highest values occurred between April 23 and May 8, with BIO 139 kg.ha-1.d-1. For areas withnatural vegetation, the average BIO was 88.34 kg.ha-1.d-1with lower values in September. Estimates of ET varied withthe lowest values of ET observedin natural vegetation 1,91±1,22 mm.d-1and the highest values in irrigated area isobserved 3,51±0,97 mm.d-1. Results of this study can assist in monitoring of river basins, contributing to themanagement irrigated agriculture, with the trend of scarcity of water resources and increasing conflicts for the wateruse.