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The Influence of Grafting and Biostimulators on the Yield and Fruit Quality of Greenhouse Tomato CV. (Lycopersicon esculentum Mill.) Grown in the Field

The Influence of Grafting and Biostimulators on the Yield and Fruit Quality of Greenhouse Tomato CV. (Lycopersicon esculentum Mill.) Grown in the Field

Four tomato cultivars Macarena F1, Faustine F1, Cathy F1 and Fanny F1 were used in the study. Seeds were sown at the end of March and transplants were grown in a greenhouse. The plants were grafted on Maxifort F1 rootstock on April 5, 6 and 21 in the years 2006, 2007, 2008 respectively without the use of biostimulators. In the case of the other combinations each year the following treatments with biostimulators were performed: watering with Goteo 0.1% solution (twice - 4 and 2 weeks before planting and three times after planting at three-week intervals), spraying with BM 86 0.1% solution (four times every three weeks starting at the blooming of first cluster). In the control combination plants were neither-nor grafted or treated with biostimulators. Plants were planted in the field at 70×100 cm spacing - 20 plants per plot. For the ripe fruits analyses the following parameters were determined: dry matter, total sugars, vitamin C, carotenoids and macroelements: N, P, K, Ca.

A higher total and marketable yield was obtained after grafting and Goteo treatments. There was a significant influence of grafting and the application of the biostimulators on the content of dry matter and total sugars, however, the highest content of vitamin C and carotenoids were obtained in the control. There was a slight increase of the content of nitrates and calcium in the fruit in the case of grafting and Goteo biostimulator watering treatments, whereas the highest content of potassium in the fruit was obtained in plants treated with BM 86 and phosphorus in the fruits from control combination plants.

Open access
The antioxidant potential of Brassica rapa L. on glutathione peroxidase, superoxide dismutase enzymes and total antioxidant status

Abstract

Research on antioxidant potential from vegetables is increasingly focused on their effects on human health. However, relatively little work has been done to investigate the antioxidant effect of crude extract and/or different fractions from Brassica rapa L. In the present study, the antioxidant potential of crude extract and its fractions from Brassica rapa L. fruit part was tested for glutathione peroxidase (GPx), superoxide dismutase (SOD) enzymes and total antioxidant status (TAS) in blood samples. Our results reveal the fact that crude extract and each analyzed fraction (i.e. aqueous, ethyl acetate and chloroform) showed a concentration dependent effects on GPx, SOD and TAS in respect with saline solution (0.9% NaCl) used as negative control and vitamin C, as positive control. Therefore, GPx levels showed a highest value in crude extract and chloroform fraction (6981 U/L both at 10 mg/ml), SOD levels showed the same results in aqueous and ethyl acetate fractions (220 U/ml both at 10 mg/ml) and TAS in crude extract and all three fractions (i.e. aqueous, ethyl acetate and chloroform, 1.68 mmol/L at 10 mg/ml for all three fractions) in respect with saline solution (p<0.05). Furthermore, vitamin C showed the highest values on all three analyzed enzymes (8769 U/L for GPx, 223 U/ml for SOD and 1.8 mmol/L for TAS at 100 μg/ml). Our investigations have been proved to be promising in terms of future potential applications of crude extract and its fractions as components in a range of phytochemicals composition and/or different pharmaceutical usage, owing to their antioxidant potential.

Open access
A combination of biochar and regulated deficit irrigation improves tomato fruit quality: A comprehensive quality analysis

Abstract

Quality of fresh produce is the most critical issue in the economics of a vegetable enterprise. In order to investigate the effect of biochar amendment and deficit irrigation on tomato fruit quality, experimental research was conducted under a rain shelter in southern China during the 2017 and 2018 growing seasons. The experiment consisted of five treatments. Crops were irrigated to 100% of field water capacity at all growth stages as treatments T1 and T2. The other treatments received 30% less irrigation water than T2 when its soil water content reached 70% of field capacity, and were designated as treatments T3, T4 and T5, applied at the vegetative (stage I), flowering and fruit development (stage II), and fruit ripening (stage III) stages, respectively. Treatment T1 included no biochar, while the other treatments included 10% biochar by weight. The results showed that the total soluble solids (TSS) content, sugar-to-acid ratio (SAR), vitamin C (VC) content, and colour index (CI) increased in the deficit irrigation treatments depending on the phenological stage, the fruit ripening stage in particular. Meanwhile, single fruit weight was significantly (p < 0.05) reduced by water deficit at stages II and III, subsequently affecting the total fruit yield. Biochar improved soil moisture conservation and had a positive effect on fruit quality as evidenced by better single quality attributes (p < 0.05) of T2 over T1. The GRA and TOPSIS appraisal methods were used to conduct the comprehensive quality analysis. Eventually, treatment T5 ranked the best in both seasons, and this was also confirmed by the combinational evaluation method.

Open access
Effect of Nitrogen Fertilization on Yield and Quality of Endive

Effect of Nitrogen Fertilization on Yield and Quality of Endive

The aim of the experiments carried out in 2007-2008 was to assess the effect of various nitrogen doses on the growth, yield and nutritional value of two endive cultivars Cigal and Excel. The effects of two types of fertilizers were compared: that of ammonium nitrate with that of the product Entec-26. On the basis of the results obtained, it was shown that endive cv. Excel produced a marketable yield that was on average by 35.5% higher than that of the cultivar Cigal. A significantly higher marketable yield of endive was obtained by fertilizing with a single dose of the fertilizer Entec-26, particularly at the rates of 90 and 135 kg N·ha-1, and also 180 kg N·ha-1. The experiments also revealed a significant effect of the fertilization method and nitrogen application rate on the biological value of the endive cultivars under evaluation. The cultivar Excel was characterized by a higher degree of nitrate accumulation, whereas the cultivar Cigal had a higher vitamin C content, dry weight, and chlorophyll content.

Open access
The Dynamics of Changes in Nutritionally Significant Ingredients of Carrot Juice after the Pasteurization

Abstract

Carrot (Daucus carota L.) belongs to the most common type of vegetable because of its consumption, versatile usage in the canning industry and because of its beneficial effects on the health of consumers. It is valuable mainly because of the high content of β-carotene, B vitamins, vitamin C, carbohydrates and minerals. The aim of this work was to compare the quality of carrot juice from different varieties of carrots regarding the content of total carotenoids and polyphenols and also to assess the dynamics of their changes evaluated under the influence of the pasteurization (85 °C). There were selected varieties of carrot such as Baltimore F1, Exhibition F1, Kamaran F1, Napoli F1, Belgrado F1, Komarno F1, Nantes, Rubina and Nandrin F1. The highest content of carotenoids, assessed by the spectrophotometry, was determined in variety Kamaran F1 (213.66 mg 100 g−1 dry matter) and the lowest in Belgrado F1 (146.80 mg 100 g−1 dry matter). After the pasteurization, the content of carotenoid decreased and ranged from 128.04 mg 100 g−1 dry matter in variety Napoli F1 to 142.55 mg 100 g−1 in Kamaran F1. The highest content of polyphenol determined by the Folin Ciocalteu method was found in fresh juice of Rubina (922.80 mg GAE 100 g−1 dry matter) and the lowest in the variety Nantes (535.75 mg GAE 100 g−1 dry matter). After the pasteurization, the content of the monitored components was found to be 450.34 mg GAE 100 g−1 dry matter in Napoli F1 to 751.95 mg GAE 100 g−1 dry matter in Komarno F1 variety.

Open access
The Effect of Nitrogen Fertilization on Yield and Nutritional Value of Onion Grown from Sets for Early Cropping

The Effect of Nitrogen Fertilization on Yield and Nutritional Value of Onion Grown from Sets for Early Cropping

In field experiment conducted in 2005-2007 the effect of a nitrogen source (ammonium nitrate, ammonium sulphate and ENTEC-26) in the amounts of 50, 100, 150, 100+50 kg N·ha-1 in onion (Allium cepa L.) Wolska cv. grown from sets for early cropping were estimated. Results of the experiment showed that ENTEC-26 was equally good source of nitrogen as ammonium nitrate and less efficient than ammonium sulphate. Split application of ammonium sulphate and ammonium nitrate produced higher while of ENTEC-26 similar yield of onion in comparison to a preplant single dose of fertilizer. Onion fertilized with ammonium nitrate and ammonium sulphate had only slightly higher content of vitamin C in bulbs and leaves than that fertilized with ENTEC-26. Plants of onion fertilized with ENTEC-26 contained also slightly higher level of reducing sugars in bulbs than by using the other source of N

Open access
Inhibition of glycoxidative modification of proteins by some substances of natural origin

Summary

Introduction: Advanced glycation end-products (AGE) and advanced oxidation protein products (AOPP) are the main products of glycoxidative modification in diabetes. Objective: The aim of this study was to identify the natural substance with the strongest antiglycoxidative properties among dietary supplements or medicines available without prescription in Poland. Methods: Bovine serum albumin (BSA), vitamin C (VC), aminoguanidine (A), quercetin (Q) and green tea (GT) were tested in vitro in comparison to controls in glycation, oxidation and glycoxidation processes. The decreased AGE and AOPP concentrations were measured as markers of these processes. Results: AGE level was reduced by 72% by VC and at least by 43% by all examined substances in the glycation process. AOPP was reduced by 99% by VC and at least by 40% by all examined substances in the oxidation process. Formation of AGE/AOPP was inhibited by 61% by Q and by 97% by A, and at least 49/88% by all examined substances, respectively. This lowering of AGE/AOPP level was statistically significant (p<0.001) for all test substances in comparison to the positive control C(+). Conclusion: All examined substances are able to inhibit glycative, oxidative and glycoxidative modification of proteins in different degrees depending on their concentration.

Open access
The Effect of a Probiotic Preparation Containing Bacillus subtilis PB6 in the Diet of Chickens on Redox and Biochemical Parameters in Their Blood

Abstract

The aim of the study was to select a dosage and time of administration of a probiotic preparation containing live cultures of Bacillus subtilis and enriched with choline to obtain the most beneficial effect on the antioxidant and biochemical status of the blood of chickens and to improve their growth performance. A total of 980 one-day-old Ross 308 chickens (7 replications of 20 individuals each) reared until their 42nd day of life were used in the experiment. The chickens were divided into seven groups of 140 each. The control group did not receive any additives. The T1 groups received a probiotic in the amount of 0.05 g/L (T1-0.05), 0.1 g/l (T1-0.1) or 0.25 g/l (T1-0.25) throughout the rearing period, while the T2 groups received the same doses of the probiotic, but only during days 1–7, 15–21 and 29–35 of rearing. Administration of a preparation containing Bacillus subtilis bacteria was shown to increase the level of ferric reducing ability of plasma (FRAP), vitamin C, and uric acid (UA), while reducing the level of peroxides (LOOH), malondialdehyde (MDA), non-esterified fatty acids (NEFA), the share of low-density fractions of cholesterol (LDL), and activity of alanine aminotransferase (ALT), asparagine aminotransferase (AST), γ-glutamyltransferase (GGT) and creatinine kinase (CK). An increase in the high-density fractions of cholesterol (HDL) and a decrease in lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) were noted as well. The results of the study indicate that 0.25 g/l of the probiotic, administered continuously (T1), clearly has the most beneficial effect in terms of enhancing antioxidant potential and reducing the level of stress indicators, without disturbing overall metabolism in the body. During the 42 days of rearing each chicken received 33.3 CFUx1011 Bacillus subtilis from the probiotic preparation. The body weight gain of chickens from T1-0.1, T1-0.2 and T2-0.25 groups was higher (P≤0.027) and more favourable compared to G–C group.

Open access
Health Promoting Chemical Components of Orange Juice

Abstract

Citrus fruit or juice can be an excellent source of health-promoting substances at breakfast. A 150-200 ml glass of orange juice daily provides many nutrients required for good human health. As has been reported, vitamin C, thiamine (vitamin B1), riboflavin, vitamin A, vitamin D, vitamin E, pantothenic acid, vitamin B6, folate are present in oranges. Citrus juices also provide minerals - calcium, potassium, iron, zinc, magnesium, copper, and phosphorous, which are part of the vital enzyme system of the human body. In addition, several compounds - flavonoids and other health-promoting substances are present in citrus fruit. There are hundreds of useful products and substances with properties, which have origin in citrus products. There are also many patents for helpful products to be made from citrus substances. Treatment of major inflammation-related ailments target on phytochemicals involved in oxidative stress, metabolic syndrome (diabetes), cardiovascular diseases, bone health (osteoporosis), skin aging, cognitive function and brain diseases, aging, allergy and immune function and cancer. A clinical study published shows that orange juice and hesperidin increase nitric oxide production in human. Orange juices have been shown to provide several important health benefits, particularly for the cardiovascular system, bone and skin health, brain health, cognitive functions, aging, and also cancer. However, the number of clinical studies available remains limited and significant efforts are necessary to provide irrefutable proof of these benefits in human

Open access
Influence of Flat Covers and Sowing Density on Yield and Chemical Composition of Garlic Cultivated for Bundle-Harvest

Influence of Flat Covers and Sowing Density on Yield and Chemical Composition of Garlic Cultivated for Bundle-Harvest

In 2003-2005 years the experiment of influence of flat covers usage (non-woven polypropylene and perforated polyethylene film) and clove sowing rate (20x2, 20x4, 20x6, 20x8 cm) on quantity and quality of garlic yield cultivated for bundle-harvest was carried out.

Covering with non-woven polypropylene and perforated film was found to increase the yield of spring garlic cv ‘Jarus’ by 24.5% in comparison to open-field cultivation (control). Nevertheless the film type covered plants were higher, produced more leaves and longer leaves what resulted in higher weight per plant.

On the other hand the leaves of garlic grown in open field contained significantly higher amount of dry matter and vitamin C compared to covered ones.

Marketable yield of garlic was also considerably dependent of clove sowing rate. The highest yield was observed while 20x2 cm density was applied. However, significantly longest leaves and highest weight per plant were obtained at 20x4 cm sowing rate.

Open access