Adubação potássica em plantas de rúcula: produção e eficiência no uso da água

Abstract

Resumo -A rúcula (Euruca sativa) é uma hortaliça relevante na alimentação humana sendo uma das mais nutritivas, ricas em minerais como potássio, enxofre e ferro, além das vitaminas A e C. Desde o final da década de 90 a rúcula vem conquistando mercado com um aumento na quantidade comercializada e na sua área de plantio. Objetivou-se pelo presente estudo avaliar o efeito de doses de potássio nas características produtivas, leitura SPAD e eficiência no uso da água por plantas de rúcula. O experimento foi realizado em casa de vegetação no período de maio a junho de 2011. A parcela experimental consistiu de vaso construído por garrafa PET de 2,5 litros, com capacidade para 1 dm -3 de solo, utilizando-se pavio de lã para irrigação por capilaridade. O delineamento experimental foi inteiramente casualizado cujos tratamentos consistiram de seis doses de K 2 O: 0; 50; 100; 150; 200 e 250 mg dm -3 utilizando-se como fonte o KCl e seis repetições. As variáveis analisadas foram leitura SPAD, número de folhas, massa fresca e massa seca da parte aérea, massa seca da raiz e eficiência no uso da água. A adubação com potássio aumenta a leitura SPAD e a eficiência no uso de água por plantas de rúcula nas doses de potássio de 156,4 e 200 mg dm -3 , respectivamente. As variáveis massas fresca e seca de plantas são influenciadas pela adubação potássica com ajuste a modelo linear de regressão. As variáveis número de folhas e massa seca de raiz não são influenciadas pela adubação potássica.Palavras-chave -Euruca sativa. Leitura SPAD. Potássio. Nutrição de plantas. Abstract -The rocket (Euruca sativa)is an important vegetable in human´s feed and one of the most nutritious, rich in minerals such as potassium, sulfur and iron, and vitamins A and C. Since the late 90's the rocket is gaining more market, with an increase in quantity sold, and its area planted. The aim for this study is to assess the effect of potassium on the yield characteristics, SPAD reading and efficiency in water use by plants of rocket. The experiment was conducted in a greenhouse during May-June 2011. The experimental plot consisted of vase built by PET 2.5 liter bottle with a capacity of 1 dm -3 of soil, using a wool wick for irrigation by capillary. The experimental design was completely randomized and its treatments consisted of six doses of K 2 O: 0; 50; 100; 150; 200 and 250 mg dm -3 and using as source KCl and six replications. The variables analyzed were SPAD readings, leaf number, fresh mass, dry mass, root dry mass and water use efficiency. The potassium fertilization increases the SPAD reading and water use efficiency by rocket plants in potassium doses of 156.4 and 200 mg dm -3 , respectively. Variables fresh and dry mass of plants are influenced by potassium fertilization with adjust of linear regression model. Variables number of leaves and root dry weight are not influenced by potassium fertilization.

Dry matter production and macronutrient leaf composition in lettuce under fertigation with nitrogen, potassium and silicon

“…In the present study, although evaluating lettuce, the marketable shoot dry matter was favored by the increase in N doses, which agrees with the result reported by Biscaro et al (2012). Porto et al (2013) evaluated six K 2 O doses (0, 50, 100, 150, 200 and 250 mg dm -3 ) on rocket plants and observed that shoot dry matter production showed a linear response, as a function of K doses, and was favored by K fertilization. In this study, the marketable shoot dry matter benefited from the K supply, which agrees with the result reported by Porto et al (2013) for rocket.…”

Arugula production as a function of irrigation depths and potassium fertilization

“…The calculations used coriander Kcb values, because of the lack of information on arugula. The initial, intermediate and final Kcb values were 0.15, 1.10 and 0.70, respectively (Silva et al, 2013).…”

“…The dose K 2 was adopted according to the recommendation of Porto et al (2013), in a study that points out the maximum water use efficiency by arugula when subjected to this dose, while the dose K 1 was adopted by the authors to study the behavior of arugula in a nutritional condition below the recommended one.…”

Growth and gas exchanges of arugula plants under silicon fertilization and water restriction

“…It is one of the most nutritious vegetables, containing minerals such as potassium, sulfur and iron, besides vitamins A and C (Porto et al, 2013). Its cultivation is mainly concentrated among medium and small farmers, which gives it economic and social importance, being a factor of aggregation between man and field (Souza Neta et al, 2013), which makes it a potential crop for cultivation in the semi-arid region.…”