Dual crop coefficient of common bean in Tangará da Serra, Mato Grosso

Abstract

A B S T R A C TThis study aimed to determine the dual crop coefficient of common bean (Phaseolus vulgaris L.) for Tangará da Serra-MT, Brazil. The study used the FAO-56 dual k c method, dividing the k c into soil evaporation coefficient (k e ), determined in microlysimeters, and basal crop coefficient (k cb ), determined in weighing lysimeters. The study was conducted from July 10 (sowing) to October 6, 2014 (harvest), using the common bean cultivar 'BRS Estilo' and a sprinkler irrigation system with a coefficient of uniformity greater than 80%. The total rainfall and irrigation during the crop cycle (84 days) was 524.8 mm; the potential evapotranspiration (ET o ) estimated for the period was 327.9 mm, whereas the crop evapotranspiration (ET c ) accumulated during the cycle, determined in lysimeters, was equal to 477.5 mm. The k cb values determined for the initial, full development and final stages were 0.32, 1.10 and 0.81, respectively, while for k e , the respective values were 0.85, 0.40 and 0.53.Coeficiente dual de cultivo do feijoeiro em Tangará da Serra, Mato Grosso R E S U M O Objetivou-se determinar, na presente pesquisa, o coeficiente duplo de cultivo do feijoeiro (Phaseolus vulgaris L.) na região de Tangará da Serra, MT, Brasil. A metodologia utilizada foi a do k c dual da FAO dividindo-se o coeficiente de cultivo (k c ) em coeficiente de evaporação do solo (k e ) determinado em microlisímetros e coeficiente basal da cultura (k cb ), determinado em lisímetros de pesagem. A cultivar de feijoeiro utilizada foi a BRS Estilo; o estudo foi realizado no período de 10/07/2014 (semeadura) a 06/10/2014 (colheita); a irrigação por aspersão foi utilizada com coeficiente de uniformidade superior a 80%; a lâmina total precipitada e irrigada durante o ciclo da cultura (84 dias) foi 524,8 mm; a evapotranspiração potencial (ET o ) estimada no período foi de 327,9 mm enquanto que a evapotranspiração da cultura (ET c ) acumulada, determinada em lisímetros, foi de 477,5 mm; o k cb determinado para as fases inicial, pleno desenvolvimento e final, foi 0,32; 1,10 e 0,81, respectivamente; para o k e , os valores foram 0,85; 0,40 e 0,53, nas fases inicial, pleno desenvolvimento e final, respectivamente. Key words:Phaseolus vulgaris basal crop coefficient evaporation coefficient irrigation Palavras-chave:Phaseolus vulgaris coeficiente basal da cultura coeficiente de evaporação irrigação

Evapotranspiration and Dual Crop Coefficient of Maize Second Season Intercropped with Crotalaria

“…It can be observed that there is a direct relationship between precipitation and air temperature, where on days when precipitation occurred, the minimum, maximum and average air temperature values were relatively lower. Fenner et al [19] observed this same behavior in research conducted in the municipality of Tangará da Serra -MT. between the minimum and the maximum, respectively, with a daily average of 2.67 mm d -…”

“…The lysimeters were previously calibrated [15,19], according to the methodology described by Faria et al [20], with a coefficient of determination greater than 0.99%, a methodology used by other authors to calibrate weighing lysimeters [14,21], where each kilogram added in calibration corresponded to 0.44 mm of water in order to establish the relationship between the signal emitted by the load cell (mv) and the mass oscillation of the assembly (kg) that occurs through evapotranspiration, irrigation, precipitation and drainage.…”

“…), the values of Ke were higher than those of Kcb, and in the rest of the evaluated period, the values of Ke are almost always lower than the values of Kcb. Fenner et al (2016), report that the relationship between Ke and Kcb at the beginning of the crop cycle is due to the fact that the soil is poorly covered, being exposed to the sun's rays, with greater evaporation, presenting higher values of Kcb and smaller than Ke.…”

“…According to Fenner et al [19], differences between Ke and Kcb measured and estimated can be attributed to specific climate characteristics of the region, as well as the type of cultivar used, which can generate greater evapotranspiration potential in the region of Tangará da Serra -MT.…”

Thermal and Soil Moisture Amplitude of Intercropped Crops

“…It can be observed that there is a direct relationship between precipitation and air temperature, where on days when precipitation occurred, the minimum, maximum and average temperature values were relatively lower. Fenner, et al [23] observed this same behavior in research conducted in the Tangará da Serra. Another inversely proportional relationship was observed in solar radiation and relative humidity, showing that on days of low radiation to an increase in relative humidity.…”