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Effects of polyethylene film covering the greenhouse, nitrogen fertiliser form, and foliar nutrition on the yield and quality of lettuce

Abstract

This study investigates the effects of two types of polyethylene films covering the greenhouse, differing in PAR transmittance, as well as two forms of nitrogen fertiliser (100% N-NO3 vs. 57% N-NO3+ 43% N-NH4), and the use of foliar nutrition on the quality and yield of lettuce grown in the spring and summer-autumn seasons. Lettuce was grown on rockwool in a film greenhouse divided into two parts, each covered with one type of film. Three times per season the plants were sprayed with a solution of molybdenum, benzyladenine, urea with molybdenum, urea with benzyladenine, and the three substances combined. The yields were examined for dry matter, nitrates, ammonia nitrogen, protein nitrogen, soluble sugars, vitamin C, and macronutrients (phosphorus, potassium, calcium and magnesium). In both seasons, lettuce cultivated in the greenhouse covered with film having a higher PAR transmittance resulted in heavier heads and contained significantly lower levels of nitrates, NH4 +, P and Mg. The effect of plot (type of film) on vitamin C content depended on the season. The form of nitrogen fertiliser influenced dry matter, vitamin C, protein nitrogen, P and Mg contents; in the summer-autumn season it also affected head weight. The plants grown on a nitrate medium produced a higher single head mass and accumulated a larger amount of nitrates than those cultivated on a nitrate-ammonia medium. No effects were observed of foliar nutrition with salt solutions on the yield and quality of lettuce in either season.

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The Effect of Nitrogen Fertilization Methods on Yield and Chemical Composition of Pumpkin (Cucurbita Maxima) Fruits Before and After Storage

The Effect of Nitrogen Fertilization Methods on Yield and Chemical Composition of Pumpkin (Cucurbita Maxima) Fruits Before and After Storage

In field experiment pumpkin of Amazonka and Karowita cvs (Cucurbita maxima) were fertilized at the rate of 200 kg N·ha-1 in the following methods: 1-100 kg N·ha-1 preplant broadcasting + 100 kg N·ha-1 as top dressing in form of 4 foliar sprays, 2-100 kg N·ha-1 preplant band placement on strips of 50 cm wide + 100 kg N·ha-1 as top dressing broadcasted on total area of field, 3- placement of N in rate of 200 kg N·ha-1 as a nests placement 25 cm apart from plant, 4-organic fertilization with composted cattle manure at the rate of 40 t·ha-1 applied in 50 cm wide strips. There were estimated total and marketable yield and chemical composition of fruits before and after 90 days of storage. Broadcasting of nitrogen gave the higher yield of fruit than banded or nested placement of this nutrient. Banded placement of nitrogen affected in the highest vitamin C content as well as higher levels of total and reducing sugars and carotenoids than in other methods of nitrogen placement. Before storage the fruits had higher amounts of soluble solids, dry matter, carotenoids, vitamin C as well as total and reducing sugars than after 90 days of storage.

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Yielding and Fruit Quality of Three Sweet Pepper Cultivars from Organic and Conventional Cultivation

Yielding and Fruit Quality of Three Sweet Pepper Cultivars from Organic and Conventional Cultivation

The investigations were undertaken to study the effect of cultivar and growing system (organic vs. conventional) on sweet pepper (Capsicum annum L.) yielding, fruit morphology and antioxidants content.

Two hybrids Caryca and Roberta and one open pollinated cultivar Mercedes all of the Polish origin were compared during 2007 and 2008 in the field experiments. Conventional production was based on mineral fertilization and chemical plant protection, while organic relied on compost fertilization and stabilized ecosystem with no chemical used according to EU Regulation 2092/91 for organic farming. The results revealed a good response of bell pepper to organic cultivation system. Marketable fruit yield was higher and morphological characters better from organic cultivation. The content of human health beneficial compounds such as acsorbic acid, total flavonoids, soluble phenols and beta- carotene were investigated at the red stage of fruit maturity. Both the cultivar and growing method influenced the level of examined compounds. Pepper fruits obtained from organic cultivation system comprised higher amount of vitamin C, beta-carotene total flavonoids and polyphenols than from the conventional. Roberta F1 revealed the higher content of vitamin C, beta-carotene than Caryca F1 and Mercedes. Moreover cultivar Roberta F1 demonstrated the highest level of polyphenols in both cultivation systems.

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Yielding and fruit quality of Lithuanian sweet cherry cultivars grown under the climatic and soil conditions of Warmia

Yielding and fruit quality of Lithuanian sweet cherry cultivars grown under the climatic and soil conditions of Warmia

In 2006-2008, yielding was determined and biometric measurement as well as chemical analysis was carried out for five Lithuanian sweet cherry cultivars, ‘Agila’, ‘Seda’, ‘Vasare’, ‘Ventenue’, and ‘Jurgita’, and two cultivars commonly grown in Poland, ‘Ulster’ and ‘Burlat’. Trees grafted on Mazzard seedlings were planted in 2002 in the orchard of the Pozorty Experimental and Production Institute in the village of Łęgajny near Olsztyn. The highest mean yield for the tested cultivars was obtained in 2008, while the lowest was in 2007, when the highest ground frosts were recorded during the cherry blossoming period. During the three years of research, the highest mean yield for the Lithuanian sweet cherry cultivars was established for the ‘Vasare’ cultivar, which together with the ‘Burlat’ cultivar made a homogenous group of the highest values. The mean fruit weight of the Lithuanian cultivars was lower than in the case of ‘Burlat’ and ‘Ulster’, while the largest fruit amongst the Lithuanian cultivars were recorded for ‘Jurgita’ and ‘Agila’. The chemical composition analysis of fruit revealed significant differences both between the cultivars and the years of the research. The fruits of the studied cultivars accumulated the lowest amounts of total saccharides and vitamin C in the coolest year under analysis, 2007. The highest mean of total saccharide content was recorded for fruit of the ‘Vasare’ and ‘Seda’ cultivars. Fruit of the ‘Agila’ cultivar accumulated the highest amounts of organic acids and vitamin C.

Open access
The Effects of Flat Covers on Overwintering and Nutritional Value of Leeks

The Effects of Flat Covers on Overwintering and Nutritional Value of Leeks

In a field study conducted in 2003-2005 leek cv. Kenton F1 planted in June was harvested in November or after overwintering in a field conditions. During the winter season plants were covered by perforated clear polyethylene film (PE) with 50 holes per 1 m2 or non-woven polypropylene agrotextile (30 g·m-2), which were removed just before the Ist and IInd term of harvest conducted at the end of March or April. The application of both tested covers considerably increased the winter hardiness of plants in comparison to non covered control. They provided the similar protection against frost damage in early spring harvest, while for delayed one to the end of April, more beneficial cover was found to be agrotextile material. Plants harvested in spring season contained lower amounts of dry matter, total sugar and vitamin C, and higher level of reducing sugar and nitrates. During the IInd term of spring harvest there was observed a decrease of dry matter and vitamin C and some increment of nitrates content in leeks in comparison to that conducted at the end of March.

Open access
Antihaemolytic activity of thirty herbal extracts in mouse red blood cells

Abstract

Reactive oxygen species (ROS) can lead to haemolysis and eventually to diseases such as thalassemia and sickle cell anaemia. Their action can be counteracted by the antihaemolytic activity of therapeutic agents. The aim of our study was to identify plants that most efficiently counteract ROS-caused haemolysis. From ten plants known for their antioxidant activity (Orobanche orientalis G. Beck, Cucumis melo L., Albizzia julibrissin Durazz, Galium verum L., Scutellaria tournefortii Benth, Crocus caspius Fischer & Meyer, Sambucus ebulus L., Danae racemosa L., Rubus fruticsos L., and Artemisia absinthium L.) we prepared 30 extracts using three extraction methods (percolation, Soxhlet, and ultrasound-assisted extraction) to see whether the extraction method affects antihaemolytic efficiency, and one extraction method (polyphenol extraction) to see how much of this action is phenol-related. Extract antihaemolytic activity was determined in mice red blood cells and compared to that of vitamin C as a known antioxidant. Nine of our extracts were more potent than vitamin C, of which G. verum (aerial parts/percolation) and S. tournefortii (aerial parts/polyphenol) extracts were the most potent, with an IC50 of 1.32 and 2.08 μg mL-1, respectively. Haemolysis inhibition depended on extract concentration and the method of extraction. These plants could provide accessible sources of natural antioxidants to the pharmaceutical industry

Open access
The Effect of Plant Mulches on the Nutritive Value of Red Cabbage and Onion

The Effect of Plant Mulches on the Nutritive Value of Red Cabbage and Onion

The effect of three methods of soil mulching: autumn or spring ploughing and leaving mulch as a cover crop on the soil surface without incorporation till the end of cabbage growth on the contents of selected nutrients in red cabbage and onion was investigated. The following plants were used as intercropped mulches: phacelia, vetch, serradella and oat. Mulching effects were compared to a non-mulched control as well as a farmyard manure application at the rate of 40 t·ha-1. Nutrient content in both vegetable species depended on weather conditions and varied in study years. Accumulation of dry matter in cabbage was favoured by phacelia and oat mulches, irrespective of the date of ploughing. Non-incorporated oat and autumn-incorporated phacelia increased dry matter content in onion. An increase in the protein content in cabbage was observed when following serradella and vetch mulches. The protein content in onion cultivated in the second year following mulching did not change significantly as a result of the influence of examined factors. Among an the mulches taken into study, serradella and oat increased the content of vitamin C in cabbage. Similarly, autumn- or spring-incorporated oat mulch and non-incorporated serradella mulch increased the content of vitamin C in onion.

Open access
Comparison of a Web-Based Dietary Assessment Tool with Software for the Evaluation of Dietary Records / Primerjava Spletne Aplikacije in Računalniškega Programa Za Ovrednotenje Prehranskih Dnevnikov

Abstract

Background. Dietary assessment in clinical practice is performed by means of computer support, either in the form of a web-based tool or software. The aim of the paper is to present the results of the comparison of a Slovenian web-based tool with German software for the evaluation of four-day weighted paper-andpencil- based dietary records (paper-DRs) in pregnant women.

Methods. A volunteer group of pregnant women (n=63) completed paper-DRs. These records were entered by an experienced research dietitian into a web-based application (Open Platform for Clinical Nutrition, OPEN, http://opkp.si/en, Ljubljana, Slovenia) and software application (Prodi 5.7 Expert plus, Nutri- Science, Stuttgart, Germany, 2011). The results for calculated energy intake, as well as 45 macro- and micronutrient intakes, were statistically compared by using the non-parametric Spearman’s rank correlation coefficient. The cut-off for Spearman’s rho was set at >0.600.

Results. 12 nutritional parameters (energy, carbohydrates, fat, protein, water, potassium, calcium, phosphorus, dietary fiber, vitamin C, folic acid, and stearic acid) were in high correlation (>0.800), 18 in moderate (0.600-0.799), 11 in weak correlation (0.400-0.599), while 5 (arachidonic acid, niacin, alphalinolenic acid, fluoride, total sugars) did not show any statistical correlation.

Conclusion. Comparison of the results of the evaluation of dietary records using a web-based dietary assessment tool with those using software shows that there is a high correlation for energy and macronutrient content.

Open access
Safety of parsley intended for processing depending on the cultivation technology and storage

Abstract

The factors that affect the value of parsley for consumption include its taste, flavour and dietary utility (vitamins C and E, β-carotene, potassium, calcium, phosphorus and iron, raw fibre, proteins) as well as the content of hazardous substances, especially nitrogen compounds. A study was carried out in 2013–2015 to determine the effect of the cultivation technology and storage on the safety of parsley intended for processing. The study material was taken from an experiment where the following fertilisers were applied to the ground: nitrogen (0, 40, 80, 120 kg N∙ha−1) and magnesium (0; 30 kg Mg∙ha−1). Parsley roots were stored for six months in a storage room at +1°C and RH 95%. The content of nitrates (V) and (III) was determined by the ion selective method immediately after the harvest and after storage in parsley roots.

The highest levels of nitrates (V) and (III) were found in parsley roots in the cultivation option where nitrogen for fertilisation was applied at the greatest amount, i.e. 120 kg N ha−1 and magnesium at 30 kg Mg∙ha−1. Regardless of the measures applied during the vegetation period, prolonged storage of parsley resulted in a decreased content of nitrates (V) and (III) in its roots. The limit for nitrogen content and the acceptable daily intake (ADI) for nitrates (1.0%) and nitrites (4.5%) were not exceeded in the cultivar under study.

Open access
Yield and nutritive value of selected endive cultivars grown for spring and autumn harvest

Yield and nutritive value of selected endive cultivars grown for spring and autumn harvest

A field experiment was carried out in the years 2007-2009 at the Research Development Station of the Department of Horticulture at the Wrocław University of Environmental and Life Sciences. The experiment involved two botanical varieties of endive: var. latifolium (nine cultivars) and var. crispum (five cultivars). Endive was cultivated from transplants produced in a greenhouse in two terms, for spring and autumn harvesting. The harvest took place 90-100 days after the seeds were sown. In the course of harvesting, the total and marketable yields were determined, while biological value was assessed on the basis of analyses regarding the content of dry matter, vitamin C, chlorophyll and carotenoids, as well as the amounts of such elements as Mg, P, K, Ca and nitrates.

Open access