Níveis de irrigação e doses de potássio sobre os teores foliares de nutrientes do maracujazeiro amarelo

Abstract

RESUMOEste trabalho foi realizado com o objetivo de avaliar o efeito de níveis de irrigação e doses de potássio aplicadas via água de irrigação por gotejamento, sobre os teores foliares de nutrientes do maracujazeiro amarelo. O trabalho foi desenvolvido no Campo Experimental da Fazenda Areão, da ESALQ/USP, em Piracicaba, SP (22°42' 30" S e 47°38' 00" W); utilizou-se, com tal propósito, um delineamento experimental de blocos ao acaso com quatro repetições, cujos tratamentos foram arranjados no esquema de parcelas subdivididas e resultaram da combinação de quatro níveis de irrigação (L 1 = 0,25 L; L 2 = 0,50 L; L 3 = 0,75 L; L 4 = 1,00 L) em que L é o volume de água médio medido em lisímetros, e cinco níveis de potás-sio (K 0 = 0,000; K 1 = 0,225; K 2 = 0,450; K 3 = 0,675 e K 4 = 0,900 kg planta -1 ano -1 de K 2 O), aplicadas via água de irrigação. Avaliou-se a concentração de nutrientes nas plantas através da diagnose foliar, realizada no período de colheita de frutos. Os teores dos nutrientes nas folhas do maracujazeiro não foram influenciados pelos níveis de irrigação nem pela interação irrigação x potássio, ao passo que a acumulação de K, Ca, Mg, B e Mn o foram pelas doses de potássio. Palavras-chave: fertirrigação, nutrição de planta, Passiflora edulisEffect of irrigation levels and potassium doses on nutrient content of yellow passion fruit leaves ABSTRACTThe objective of this work was to evaluate the effect of irrigation and potassium levels applied through irrigation water by drip irrigation on the nutrient content of yellow passion fruit. The experiment was performed in the Experimental Field of the Areão Farm at ESALQ/USP, Piracicaba, São Paulo, Brazil (22°42' 30" S e 47°38' 00" W). An experimental design of randomized blocks in subdivided plots with four replications was used. The treatments resulted from the combination of four irrigation levels (, in which L is the average water depth measured in lysimetr, and five potassium doses (K 0 = 0.00; K 1 = 0.225; K 2 = 0.450 K 3 = 0.675 and K 4 = 0.90 kg plant -1 year -1 of K 2 O), applied through irrigation water every seven days. The nutrient concentration in the plants was evaluated through leaf diagnosis, performed during the fruit harvests period. The nutrient content in passion fruit leaves was not influenced by irrigation levels and irrigation X potassium interaction, but the concentrations of K, Ca, Mg, B and Mn were influenced by potassium doses.

Growth and Nutritional Status of Passiflora edulis f. Flavicarpa, With the Application of Organic Compound in Amazonian Soil

“…The leaf content of calcium ranged from 8.18 (60%) to 20.71 g kg -1 (15%) with an average content equivalent to 13.57 g kg -1 . The values were below those observed by Sousa et al, (2008) and close to the values found by Martins (2009) and above those observed by Morais et al (2011). In the soil, the calcium content varied from 1.65 to 3.98 mg dm -3 , for the control and 60% organic compost treatment, respectively (Table 1).…”

“…The need for potassium by this crop needs to be determined and/or adjusted according to the cultivation and management system, considering that the recommendations of conventional fertilization with potassium in Brazil found in the literature are largely variable, from 50 to 530 kg of K 2 O ha -1 year (Borges et al, 2002). With reference to the evaluation of the nutritional status of yellow passion fruit plants by means of foliar diagnosis, Sousa et al (2008) verified that, even with the frequent application of potassium, the plants presented deficiency of this element, which according to the authors, can be attributed to plant age, leaf collection period, emission of flowers, tendrils, flower buds and fruit development. According to Freitas et al (2011) andAraújo et al, (2005), potassium is most required by the plants during fruiting, formation and maturation of the fruits, since this is the most important nutrient for passion fruit at this phase.…”

Tolerância Do Pepino À Salinidade Em Ambiente Protegido: Efeitos Sobre Propriedades Físico-Químicas Dos Frutos

“…Suprimento inadequado de potássio ocasiona o funcionamento irregular dos estômatos, podendo diminuir a assimilação de CO 2 e a taxa fotossintética (Montoya et al, 2006). Souza et al (2008) afirmam que maiores absorções de Ca, Mg e B pelo maracujazeiro ocorrem na ausência ou com pequenas doses de K aplicados, elementos estes que são essenciais para a formação das plantas e consequentemente, para formação dos frutos em termos de quantidade e qualidade. Diante do exposto, este trabalho teve como objetivo avaliar os frutos de pepino, em relação aos parâmetros pH, sólidos solúveis totais (%), acidez total titulável (g 100g -1 de amostra) e firmeza de polpa (kgf cm -2 ), a partir do cultivo em ambiente salino, utilizando dois tipos diferentes de manejo de fertirrigação e seis níveis iniciais de salinidade do solo em ambiente protegido, utilizando solo arenoso.…”

Accumulation and exportation of nutrients by yellow Passion fruit cv. IAC 275

“…The climatic conditions in the experimental period are also related to the observed productivity. The rainfall was 908.3 mm from August to June, 11 months, being slightly below the annual regional average of 1,353.2 mm (CEPAGRI, 2017) and close to the levels of 1,293 and 944.2 mm year, verified by Carvalho et al (2000) and Sousa et al (2008), respectively, which guaranteed better crop yields, but in the harvest cultivation (40.9 t ha -1 and 41.3 t ha -1 ). Thus, the total water quantity was sufficient for the development of the crop in the present experiment, but it was distributed irregularly in the period (Figure 1), with a deficit in the months of October and December, which may have negatively influenced the productivity.…”