Fertilisation is as old as is the cultivation of crops. In the 19th century, plant nutrition beca... more Fertilisation is as old as is the cultivation of crops. In the 19th century, plant nutrition became an area of research in the field of agricultural chemistry. Liebig’s “Law of the Minimum” (1855) is still the basis for plant nutrition. It states that the exploitation of the genetically fixed yield potential of crops is limited by that variable, which is insufficiently supplied to the greatest extent. With a view to abiotic and biotic stress factors, this postulation should be extended by the phrase “and/or impaired by the strongest stress factor”. Interactions between mineral elements and plant diseases are well known for essential macro- and micronutrients, and silicon. In comparison, the potential of fertilisation to alleviate abiotic stress has not been compiled in a user-orientated manner. It is the aim of this chapter to summarise the influence of nutrient deficiency in general, and the significance of sodium, potassium, and silicon, in particular, on resistance of crop plants...
Mittlere Kupfer-Gesamtgehalte unbelasteter Ackerböden in Deutschland (Hintergrundgehalte) liegen ... more Mittlere Kupfer-Gesamtgehalte unbelasteter Ackerböden in Deutschland (Hintergrundgehalte) liegen zwischen 8 und 42 mg Cu/kg Boden (TM), ein Großteil der Böden (90. Perzentil) unterschreitet einen Gehalt von 70 mg Cu/kg deutlich. Aufgrund seiner geringen Mobilität reichert sich Kupfer, welches über den Pflanzenbedarf hinaus zugeführt wird, im Boden an. Als kritische Kupfer-Gesamtgehalte in Böden gelten nach derzeitiger Rechtslage [(BBodSchV (Anonym, 1999), AbfKlärV (Anonym, 1992), BioAbfV (Anonym, 1998)] Werte >60 mg/kg Cu. Kupfereinträge in der Landwirtschaft entstammen vor allem dem Einsatz von Mineral- und Wirtschaftsdüngern sowie Pflanzenschutzmitteln. Mit der Düngung werden üblicherweise Frachten in der Größenordnung von 10-500 g Cu/ha·a ausgebracht. Diese liegen weit unter den für die Verwendung Cu-haltiger Pflanzenschutzmittel erlaubten Frachten, die nach EU-Recht bis zu 6000 g Cu/ha·a betragen dürfen. Dem steht die auf ökotoxikologischer Basis abgeleitete zulässige Zusatzf...
Tropaeolum majus L. is a herb with antimicrobial activity in humans, caused by the degradation pr... more Tropaeolum majus L. is a herb with antimicrobial activity in humans, caused by the degradation product benzyl-isothiocyanate derived from enzymatic cleavage of glucotropaeolin. Piglets were fed diets with a graded supplementation of Tropaeolum majus for five weeks. Tropaeolum majus was supplemented at an upper dosage level of 1 g/kg with the feed, equaling 48.7 mg/kg glucotropaeolin, which resulted in a benzyl-isothiocyanate concentration in the urine of up to 2.4 mg/L, which is high enough to control a broad range of bacteria. On average 3.1 - 7.3% of the glucotropaeolin taken up by the animals was excreted as bioactive benzyl-isothiocyanate. Supplementation of the feed with Tropaeolum majus had no effect on growth performance of piglets.
Proceedings of the 11th International World Fertilizer Congress held at Faculty of Agricultural and Applied Biological Sciences, Universiteit Gent on 7 - 13 September 1997 in Gent, Belgium : vol. 3
Tropaeolum majus L. - Life Cycle and Optimum Harvest Time for Highest Glucotropaeolin Contents
Phyton; annales rei botanicae
Garden nasturtium (Tropaeolum majus L.) has been chosen as medicinal plant 2013 in Germany and it... more Garden nasturtium (Tropaeolum majus L.) has been chosen as medicinal plant 2013 in Germany and its health effects are well described. In the presented study phenological characteristics of T. majus during the vegetation cycle have been assessed together with the determination of the glucotropaeolin (GT) content in different plant parts and GT yield (GT concentration × yield). A high concentration of this bio-active compound is a prerequisite for the commercial use of the plant. Plant samples were taken weekly from field grown T. majus. Sulfur (S) was applied at two rates (0 and 100 kg ha–1 S) in order to enhance GT biosynthesis. The best GT yield was determined during main vegetative growth until flowering. The GT content decreased steeply in vegetative plant parts after main flowering, indicating transport of GT into flowers and seeds. Generally, growth of T. majus is characterized by a long flowering period where new flowers emerged side by side with developing and maturing seeds....
From seed to cure: aspects of cultivation, preparation and administration of Tropaeolum majus L
Nasturtium (Tropaeolum majus L.) is a herb with a proven antimicrobial activity due to benzyl-iso... more Nasturtium (Tropaeolum majus L.) is a herb with a proven antimicrobial activity due to benzyl-isothiocyanate, the degradation product of glucotropaeolin. A non-destructive harvest of leaves in combination with a gentle drying procedure at 40° C delivered the highest concentration of extractable glucotropaeolin. In an experiment with piglets, direct and graded supplementation of T. majus with feed was performed over a period of five weeks. T. majus was supplemented at an upper dosage of 1 g/kg with the feed, equaling 48.7 mg/kg glucotropaeolin, which resulted in a benzyl-isothiocyanate concentration in the urine of up to 16 µmol/L. This concentration ought to be high enough to control a broad range of bacteria. Up to 7.3% of the glucotropaeolin taken up by the animals was excreted as bioactive benzyl-isothiocyanate via the urine. No effect was observed on the intestinal microbiota and supplementation with T. majus had also no effect on growth performance of healthy piglets.
Heavy Metal Loads to Agricultural Soils in Germany from the Application of Commercial Phosphorus Fertilizers and Their Contribution to Background Concentration in Soils
Cola soft drinks for evaluating the bioaccessibility of uranium in contaminated mine soils
Science of The Total Environment, 2011
There is a rising need for scientifically sound and quantitative as well as simple, rapid, cheap ... more There is a rising need for scientifically sound and quantitative as well as simple, rapid, cheap and readily available soil testing procedures. The purpose of this study was to explore selected soft drinks (Coca-Cola Classic®, Diet Coke®, Coke Zero®) as indicators of bioaccessible uranium and other trace elements (As, Ce, Cu, La, Mn, Ni, Pb, Th, Y, Zn) in contaminated soils of the Mary Kathleen uranium mine site, Australia. Data of single extraction tests using Coca-Cola Classic®, Diet Coke® and Coke Zero® demonstrate that extractable arsenic, copper, lanthanum, manganese, nickel, yttrium and zinc concentrations correlate significantly with DTPA- and CaCl₂-extractable metals. Moreover, the correlation between DTPA-extractable uranium and that extracted using Coca-Cola Classic® is close to unity (+0.98), with reduced correlations for Diet Coke® (+0.66) and Coke Zero® (+0.55). Also, Coca-Cola Classic® extracts uranium concentrations near identical to DTPA, whereas distinctly higher uranium fractions were extracted using Diet Coke® and Coke Zero®. Results of this study demonstrate that the use of Coca-Cola Classic® in single extraction tests provided an excellent indication of bioaccessible uranium in the analysed soils and of uranium uptake into leaves and stems of the Sodom apple (Calotropis procera). Moreover, the unconventional reagent is superior in terms of availability, costs, preparation and disposal compared to traditional chemicals. Contaminated site assessments and rehabilitation of uranium mine sites require a solid understanding of the chemical speciation of environmentally significant elements for estimating their translocation in soils and plant uptake. Therefore, Cola soft drinks have potential applications in single extraction tests of uranium contaminated soils and may be used for environmental impact assessments of uranium mine sites, nuclear fuel processing plants and waste storage and disposal facilities.
Summary In Europe organic farming is directed by the EU-Regu- lation 2092/91. The main difference... more Summary In Europe organic farming is directed by the EU-Regu- lation 2092/91. The main differences between organic and conventional farming systems are significant restrictions for the use of fertilisers and pesticides on organic farms. Additionally, import of fertilisers, fodder, manure, phar- maceuticals, cleansing agents and stocking densities are limited. Thus it is concluded that organic farming has a high potential to contribute to marine environmental pro- tection and is in accordance to the HELCOM Annex III on 'Prevention of pollution from agriculture'. Organic farms are operating at a significantly lower yield level than conventional farming systems. Recent lit- erature shows that conventional farms would have to set aside 50 % of their arable land to reach the lower level of nitrate leaching of organic farms. Vice versa organic farms would realise 25 % more yield at the same level of nitrate leaching. The presented literature based survey shows that today's ...
Intensification of tropical agricultural systems by increasing fertilizer input and technology is... more Intensification of tropical agricultural systems by increasing fertilizer input and technology is a current trend in developing regions. Under intensive management, erosion impacts on crop productivity may not be detected in the short term. However, long‐term impacts are expected because erosion rates in tropical agroecosystems are usually greater than the rate of soil formation. A temporal function of soil‐depth change was defined and named life time Conceptually, soil's life time is the time until a minimum soil depth needed for sustaining crop production is reached. The life‐time function was applied to the Ceveiro watershed (1990 ha) located at the Southeastern part of Brazil, and compared with sugarcane (Saccharum officinarum L.) yield loss estimations. Soil erosion prediction was made employing the Water Erosion Prediction Project. The mean soil erosion rate for the area was 15 Mg ha−1 yr−1, and sugarcane showed the highest mean value of 31 Mg ha−1 yr−1 The half life time ...
Correction for protein content in the determination of the glucosinolate content of rapeseed by the X-RF method
Journal of the Science of Food and Agriculture, 1992
Page 1. J Sci Food Agric 1992, 58, 431433 Correction for Protein Content in the Determination of ... more Page 1. J Sci Food Agric 1992, 58, 431433 Correction for Protein Content in the Determination of the Glucosinolate Content of Rapeseed by the X-RF Method Fangjie Zhao,* Eric J Evans, Paul E Bilsborrow, Ewald Schnug and J Keith Syers ...
Influence of Nitrogen and Sulfur Fertilization on the Alliin Content of Onions and Garlic
Journal of Plant Nutrition, 2004
ABSTRACT Onion (Allium cepa L.) and garlic (Allium sativum L.) were among the earliest cultivated... more ABSTRACT Onion (Allium cepa L.) and garlic (Allium sativum L.) were among the earliest cultivated crops and have been popular in folk medicine for centuries. Alliins (cysteine sulfoxides) are the characteristic sulfur (S) containing secondary metabolites of Allium species like onions, shallot, garlic, leek and chives and they cause taste and sharpness and are criteria for the pharmaceutical quality. The influence of the S nutritional status on the content of secondary S containing metabolites was shown for different crops such as oilseed rape, mustard, nasturtium, and allium species. It was the aim of this study to investigate the influence of the S and nitrogen (N) supply on the alliin content of onion and garlic and to evaluate the significance for crop quality. In a greenhouse experiment three levels of N and S were applied in factorial combinations of 0, 50, and 250 mg pot(-1) S and 250, 500, and 1000 mg pot(-1) N. 8 plants were grown in a Mitscherlich pot containing 8 kg sand. Leaves and bulbs were sampled twice during the growth period in order to follow up translocation processes. The first sampling was carried out when leaves were developed, but bulb growth had not yet started and the second one during main bulb growth. An increasing S supply was related to an increasing alliin content in leaves and bulbs of both crops, whereas nitrogen fertilization had only a minor influence. The allin content in bulbs could be doubled by S fertilization. A translocation of alliin from leaves to bulbs was found so that time of harvest has a strong influence on the alliin content. At the beginning of plant development high alliin contents were found in leaves, while with bulb development they were translocated into this plant organ. The results show that the potential health benefits of Allium species could be distinctly improved by S fertilization.
The most important active compound in garlic is alliin. Sulfur (S) fertilization was shown to sig... more The most important active compound in garlic is alliin. Sulfur (S) fertilization was shown to significantly increase the alliin concentration in garlic cloves, while high nitrogen (N) levels had an adverse effect. The effect of graded N and S application on the storage life of garlic has been paid little attention so far. A bifactorial field trial with 4 levels of N and S was conducted in a randomized block design. At harvest, 40 bulbs per treatment were stored under terms comparable to the storage conditions in average households (20°C, dry, and dim) for 83 days. Every 3 weeks, samples were analyzed for their alliin and water content. The alliin concentration in peeled garlic cloves increased during storage from on average 9.2 mg g À1 dry weight at harvest to 21.4 mg g À1 dry weight after 83 days of storage. S fertilization increased the alliin concentration by a factor of 2.3 from 11.4 mg g À1 in the control treatment to 26.6 mg g À1 dry weight at the highest S level of 45 kg ha À1 after 83 days of storage. N fertilization decreased by a trend of the alliin content. Fertilizer rates had only a minor influence on water losses from bulbs at short-term storage. After 83 days of storage, water losses were by trend lower at higher S levels, and this relationship proved to be significant when no N was applied. Best quality in terms of high alliin contents was obtained during the entire storage time at an S level of at minimum 30 kg ha À1 S if no N was applied. The results show that the physiological S demand of 15 kg ha À1 S for optimum yield is lower than the S requirement of 30 kg ha À1 S for a longer storage life.
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