Saline water irrigation strategies and potassium fertilization on physiology and fruit production of yellow passion fruit

ABSTRACT The objective of this study was to evaluate the effects of saline water irrigation management strategies and potassium doses on the concentration of photosynthetic pigments, gas exchange, and fruit production of ‘BRS GA1’ yellow passion fruit. The experiment was carried out under field conditions using a randomized block design, with treatments based on a 6 × 2 factorial scheme, related to six management strategies for irrigation with saline water (irrigation with low-salinity water throughout the crop cycle-WS; irrigation with high-salinity water in the vegetative stage-VE; flowering stage-FL; fruiting stage-FR; and successively in vegetative/flowering stages-VE/FL and vegetative/fruiting stages-VE/FR) and two doses of potassium (60 and 100% of the recommendation), with four replicates. The dose of 100% recommendation corresponded to 345 g of K2O plant-1 year-1. High electrical conductivity irrigation water (4.0 dS m-1) was used in different phenological stages according to treatment, alternating with water of low electrical conductivity (1.3 dS m-1). The synthesis of chlorophyll a and b, stomatal conductance, instantaneous carboxylation efficiency and water use efficiency of ‘BRS GA1’ yellow passion fruit were reduced under irrigation with water of 4.0 dS m-1 in all strategies adopted. Fertilization with 60% of the K recommendation promoted greater number of fruits and yellow passion fruit yield. Irrigation with 4.0 dS m-1 water in the vegetative/flowering and flowering stages reduced the yield of yellow passion fruit.

Gas exchange in yellow passion fruit under irrigation water salinity and nitrogen fertilization

ABSTRACT The objective of this study was to evaluate the gas exchange of ‘Redondo Amarelo’ passion fruit seedlings under the mitigating action of nitrogen fertilization on the salinity of irrigation water. The experiment was carried out in a greenhouse of the Universidade Federal de Campina Grande (CCTA-UFCG), Campus of Pombal, PB, Brazil, The experimental design was in randomized blocks, split plots, comprising five irrigation water electrical conductivities (plot) (ECw) (0.3; 1.0; 1.7; 2.4 and 3.1 dS m-1) and five doses of nitrogen (subplot) (60; 80; 100; 120 and 140% of 300 mg of N dm-3), in five blocks. Plants were grown in pots (Citropote JKS®) with volume of 3.780 mL, filled with soil, bovine manure, wood shavings in a proportion of 2:1:0.5 (mass basis), respectively. Water with salinity levels was applied in the period from 40 to 85 days after sowing. The internal CO2 concentration, transpiration, stomatal conductance and photosynthesis were measured at 55 and 70 days after sowing. There was an attenuating effect of nitrogen doses at irrigation water electrical conductivities of 1.7 and 2.4 dS m-1 on photosynthesis at 55 DAS. Irrigation water salinity reduces most of the variables evaluated, especially at the highest level studied (3.1 dS m-1).

Anti-Zika Virus Effects, Placenta Protection and Chemical Composition of Passiflora edulis Seeds Ethanolic Extract

Various beneficial biological activities have been reported for passion fruit (Passiflora edulis), grown in tropical and subtropical regions. However, no study has yet demonstrated its action against the Zika virus (ZIKV) infection. The present study aimed to investigate the anti-ZIKV of the ethanolic passion fruit seed extract (PFSE), from which, liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis allowed to putatively annotate the occurrence of piceatannol, astringin, scirpusin A, scirpusin B, isookanin-7-O-glucoside and naringenin-7-O-glucoside, two quadranguloside derivatives, tyrosine, and phenylalanine. PFSE is well tolerated by cell lines (Vero E6 and HTR-8/SVneo) and tissue explants from the human placenta. With 1- and 24-h treatments, PFSE consistently reduced the viral load and NS1 protein expression of the two strains of ZIKV (MR766 and PE243) in placental explants and cell lines. Thus, PFSE has a promising potential for developing anti-ZIKV treatments, protecting the placenta against infection caused by ZIKV, along with relevant antioxidant potential, represented by ferric reducing antioxidant power (FRAP) of 390.5 Trolox eq per g dry extract and half maximal inhibitory concentration (IC50) for 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) of 12.1 μg mL–1, and more than 90% protection from lipid peroxidation. Although further studies need to be conducted, PFSE treatment was safe and effective in trophoblast cells and placental explants, thus representing a promising class of all-accessible products based on the reuse of industrial by-products.

Physicochemical and sensorial characterization of yacon mixed juice with bioactive properties

ABSTRACT: This study developed a palatable, acceptable, and functional mixed juice of pineapple (Ananas comosus var. Comosus), passion fruit (Passiflora edulis flavicarpa degener), and yacon (Smallanthus sonchifolius), with enhanced bioactive and prebiotic compounds. The ideal proportion of fruit and yacon was derived after planning a mixture with six formulations and by evaluating their bioactive compounds and organic acid profile. The best formulation sensory evaluation was performed by the Just-About-Right test (JAR) and global acceptance. The chosen mixed juice (M6 - 30% pineapple, 45% passion fruit, and 30% yacon) presented results that showed elevated levels of antioxidant activity (82.5% DPPH* inhibition), carotenoids (0.97 mg.100g-1), and total polyphenols (70.28 mg.100g-1). Total flavonols (23.95 mg.100g-1), total anthocyanins (1.37 mg.100g-1), gallic acid (3.13 μg.mL-1), quercetin (2.25 μg.mL-1), syringic acid (1.01 μg.mL-1), citric acid (949.30 mg.100g-1), malic acid (140.35 mg.100g-1), and 0.58% of dietary fiber were also reported. Sensorially, consumers perceived high acidity, strong flavor, and a fibrous texture, which might have affected the global acceptance of the juice (6.0). Results indicated the feasibility of obtaining a functional and palatable mixed juice using yacon.