Manejo da irrigação no feijoeiro cultivado em plantio direto

Abstract

RESUMOEste trabalho foi desenvolvido com objetivo de se avaliar três formas de manejar a irrigação do feijoeiro. A cultivar de feijão preto BRS Supremo foi submetida ao manejo da irrigação por tensiometria, tanque Classe A e Penman-Monteith. Avaliaram-se a produtividade de grãos, número de vagens por planta, número de grãos por vagem, massa de 100 grãos, altura da planta, lâmina total e eficiência de uso da água. O método do tanque propiciou a maior lâmina acumulada e a maior frequência de irrigação. A lâmina total estimada por tensiometria foi 29,7 e 17,8% menor que a estimada pelos métodos do tanque e de Penman-Monteith, respectivamente. Houve diferenças significativas quanto à produtividade de grãos, número de grãos por vagem e altura da planta. O método do tanque propiciou a obtenção de maiores produtividades enquanto o método da tensiometria levou à economia de água de irrigação ocorrendo, no entanto, redução da produtividade. Plantas de feijoeiro submetidas a déficit hídrico de 21 e 37%, respectivamente, nas fases vegetativa e reprodutiva tiveram sua produtividade reduzida em 29%. Déficit hídrico de 22% na fase reprodutiva reduziu a produtividade do feijoeiro em 15%. Não foram observadas diferenças significativas na eficiência do uso da água. Palavras-chave:Phaseolus vulgaris L., necessidades hídricas, tanque Classe A, Penman-Monteith Irrigation management in bean crop cultivated in no-tillage system ABSTRACT The objective of this research was to evaluate three methods of irrigation management in the bean crop. The variety of black bean BRS Supremo was submitted to irrigation management by tensiometry, Class A pan method, and Penman-Monteith. The productivity of grains, number of grains per plant, grains per berry, weight of 100 grains, height of plants, total water depth and water use efficiency were evaluated. The method of the Class A pan promoted the largest accumulated water depth and the largest irrigation frequency. The tensiometry underestimated in 29.7 and 17.8% the total water depth estimated by the Class A pan method, and Penman-Monteith, respectively. The results demonstrated that there were significant differences for the productivity of grains, number of grains per berry and height of plants. The Class A pan method favored larger productivities, while the tensiometry took the economy of irrigation water, having, however, reduction of the productivity. Bean plants subjected to water deficit of 21 and 37%, respectively, in the vegetative and reproductive stages, have their productivity reduced by 29%. Water deficit of 22% in the reproductive stage reduces the productivity by 15%. There were no significant differences in the water use efficiency.

Common bean evapotranspiration estimated by orbital images

“…It is considered staple food and one of the main protein sources in the population diet. Although this culture is characterized as one of the main crops in Brazil (Cunha et al, 2013), it is often grown as second harvest, which, in much of the country, is when the drought begins. Thus, irrigation use is essential for bean growth.…”

Early sowing can improve irrigation water use efficiency and yield of common bean

“…Bizari et al (2009) and Cunha et al (2013) obtained maximum irrigation water use efficiency of 1.05 kg m -3 and 0.92 kg m -3 for the Carioca Precoce and BRS Supremo cultivars, respectively.…”

Sowing time affecting the development of common bean cultivars in Lichinga, Province of Niassa, Mozambique

“…In the second growing season, the rainfall was 697.4, 569.5, and 418.2 mm for the first, second, and third sowing time, respectively. According to Cunha et al (2013) and Fancelli & Dourado Neto (2007), common bean requires at least 300 mm of well distributed rainfall during the crop cycle and in the critical periods during the flowering and the initial stage of pod formation (Cunha et al, 2013). In this sense, we could observe that in all sowing time, the amount of rain was higher than 300 mm; however, it is important to note that when sowing time is delayed, the amount of rain reduced (from 790 to 563 mm in 2012/2013 and from 697 to 418 mm in 2013/2014).…”

“…As for precipitation, the common bean is considered a crop of low tolerance to water stress and requires at least 300 mm of rainfall during the cycle and in the critical periods during the flowering and the initial stage of pod formation (Cunha et al, 2013), water consumption can reach 5 mm per day (Fancelli & Dourado Neto, 2007). The risks caused to common bean grain production due to reduced availability of water can be minimized when the crop is sowed in periods with high probability of rainfall during periods of increased demand for crop.…”