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Fertilisation
Kinds of Fertilisation Selected AbstractsLaboratory-based reproduction success of ruffe, Gymnocephalus cernuus (L.), in brackish water is determined by maternal propertiesECOLOGY OF FRESHWATER FISH, Issue 2 2006A. Albert Abstract,, Body length, age, egg size, embryo salinity tolerance and length at hatching of the freshwater (salinity <0.1 ppt, Lake Peipsi) and brackish-water (salinity 2,6 ppt, Pärnu and Matsalu Bay) ruffe, Gymnocephalus cernuus (L.), were examined to reveal their reproductive success in moderate salinity. Eggs of females originating from brackish water were significantly larger than eggs of freshwater females. No correlation between egg size and female size and age was found in brackish-water populations. In the freshwater population there was a small negative correlation between egg size and female size, but no correlation with female age. Fertilisation by sperm of males of different origin (brackish water or freshwater) produced no significant differences at any critical developmental stage (fertilisation, gastrulation, hatching) in the development of eggs from brackish-water or freshwater females at 3.3, 5.5, 7.7 and 9.9 ppt salinity. Survival rates in different salinity depended only on female origin; embryonic salinity tolerance was higher in ruffe inhabiting brackish water. Obviously, embryo salinity tolerance in ruffe is determined by egg qualities. [source] What choices should we be able to make about designer babies?HEALTH EXPECTATIONS, Issue 3 2006A Citizens' Jury of young people in South Wales Abstract Background, Young people will increasingly have the option of using new technologies for reproductive decision making but their voices are rarely heard in debates about acceptable public policy in this area. Capturing the views of young people about potentially esoteric topics, such as genetics, is difficult and methodologically challenging. Design, A Citizens' Jury is a deliberative process that presents a question to a group of ordinary people, allows them to examine evidence given by expert witnesses and personal testimonies and arrive at a verdict. This Citizens' Jury explored designer babies in relation to inherited conditions, saviour siblings and sex selection with young people. Participants, Fourteen young people aged 16,19 in Wales. Results, Acceptance of designer baby technology was purpose-specific; it was perceived by participants to be acceptable for preventing inherited conditions and to create a child to save a sibling, but was not recommended for sex selection. Jurors stated that permission should not depend on parents' age, although some measure of suitability should be assessed. Preventing potential parents from going abroad was considered impractical. These young people felt the Human Fertilisation and Embryology Authority should have members under 20 and that the term ,designer baby' was not useful. Conclusions, Perspectives on the acceptability of this technology were nuanced, and based on implicit value judgements about the extent of individual benefit derived. Young people have valuable and interesting contributions to make to the debate about genetics and reproductive decision making and a variety of innovative methods must be used to secure their involvement in decision-making processes. [source] Flood events overrule fertiliser effects on biomass production and species richness in riverine grasslandsJOURNAL OF VEGETATION SCIENCE, Issue 5 2007Boudewijn Beltman Abstract Question: Do severe winter flood events lift the nutrient limitation of biomass production in a river floodplain? How does this affect plant species richness? How long do the effects last? Location: Floodplain grassland on calcareous sandy loam near river Rhine in The Netherlands. Methods: Plots were fertilised with four treatments (control, N, P, N+P) for 21 years; plant species composition, vegetation biomass and tissue nutrient concentrations were determined every year between 1985 and 2005. Results: Fertilisation with N generally increased biomass production and reduced species richness, but these effects varied over time. During the first four years of the experiment, biomass production appeared to be co-limited by N and P, while N fertilisation dramatically reduced plant species richness; these effects became weaker subsequently. Following two extreme winter floods in 1993,94 and 1994,95 and a drought in spring 1996, the effects of fertilisation disappeared between 1998 and 2001 and then appeared again. Flooding caused an overall reduction in species richness (from c. 24 to 15 species m -2) and an increase in biomass production, which were only partly reversed after ten years. Conclusions: Long time series are necessary to understand vegetation dynamics and nutrient limitation in river floodplains, since they are influenced by occasional flood and drought events, whose effects may persist for more than ten years. A future increase in flooding frequency might be detrimental to species richness in floodplain grasslands. [source] Making ,bad' deaths ,good': the kinship consequences of posthumous conceptionTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 1 2001Bob Simpson Recent developments in assisted reproduction mean that a child may now be born long after its father's demise. Acts of posthumous conception raise a host of complex ethical and social issues. The article draws attention to these by means of an analysis of the medical, legal, and political commentaries generated by the case of Diane Blood in her dispute with the Human Fertilisation and Embryology Authority, which had prevented her from using her deceased husband's sperm to become pregnant. Analysis of this and similar cases reveals that the desire for offspring following the death of a husband or partner has significant consequences for notions of marriage, paternity, memoriam, and inheritance . The article identifies as an underlying theme in acts of posthumous conception an attempt to ameliorate the grief of a widow, a family, and the wider society by making ,bad' deaths to some extent ,good'. To achieve this transformation the meaning of sperm within reproductive transactions is subject to radical reinterpretations which simultaneously commodotize and sacralize human gametes. [source] Fertilisation and pregnancy outcome after ICSI in globozoospermic patients without assisted oocyte activationANDROLOGIA, Issue 1 2009S. Bechoua Summary The successful outcome of intracytoplasmic sperm injection (ICSI) with globozoospermic sperm and non-activated oocytes is reported. Three couples underwent ICSI treatment and two of the patients were siblings. Forty-four non-activated oocytes were injected, 26 oocytes fertilised normally and 17 good quality embryos were obtained. Six embryo transfers were carried out, three with fresh embryos and three with frozen-thawed embryos. Three pregnancies resulted from the fresh embryo transfers and additionally two pregnancies were obtained after the transfer of frozen-thawed embryos. Two healthy babies were born. One twin pregnancy is ongoing. Our case reports demonstrate that in some ICSI attempts undertaken with globozoospermic sperm cells from two of our patients, high fertilisation rates, pregnancies and live births can be achieved, without artificially activated oocytes. Our data also suggest that in some cases, round-headed spermatozoa lack the capacity to activate the oocyte. Therefore, it cannot be excluded that artificial oocyte activation could be of help in globozoospermic patients with complete fertilisation failure. [source] Sharing genetic origins information in third party assisted conception: a case for Victorian family values?CHILDREN & SOCIETY, Issue 1 2000Eric Blyth In the United Kingdom (UK) approximately 2500 children are born each year as a result of third party assisted conception. Since formal record keeping by the statutory regulatory body, the Human Fertilisation and Embryology Authority, began in 1991, the total number of children known to have been born from all forms of third party assisted conception exceeds 13 500. Although the records contain information about these children's genetic origins, including the identity of the donor, current legislation severely circumscribes their ability to access this information and, save in very exceptional circumstances, they are not permitted to learn the identity of the donor. Consequently, they are the only individuals in the UK whose inability to learn the identity of both their genetic parents is formally endorsed by statute. This paper identifies different approaches to exchanging genetic origins information in third party assisted conception. It provides a critique of the model currently in force in the UK and advocates its replacement by a system that more closely resembles that introduced in Victoria (Australia) in 1998. Copyright © 2000 John Wiley & Sons, Ltd. [source] Laboratory-based reproduction success of ruffe, Gymnocephalus cernuus (L.), in brackish water is determined by maternal propertiesECOLOGY OF FRESHWATER FISH, Issue 2 2006A. Albert Abstract,, Body length, age, egg size, embryo salinity tolerance and length at hatching of the freshwater (salinity <0.1 ppt, Lake Peipsi) and brackish-water (salinity 2,6 ppt, Pärnu and Matsalu Bay) ruffe, Gymnocephalus cernuus (L.), were examined to reveal their reproductive success in moderate salinity. Eggs of females originating from brackish water were significantly larger than eggs of freshwater females. No correlation between egg size and female size and age was found in brackish-water populations. In the freshwater population there was a small negative correlation between egg size and female size, but no correlation with female age. Fertilisation by sperm of males of different origin (brackish water or freshwater) produced no significant differences at any critical developmental stage (fertilisation, gastrulation, hatching) in the development of eggs from brackish-water or freshwater females at 3.3, 5.5, 7.7 and 9.9 ppt salinity. Survival rates in different salinity depended only on female origin; embryonic salinity tolerance was higher in ruffe inhabiting brackish water. Obviously, embryo salinity tolerance in ruffe is determined by egg qualities. [source] Fatty acid ruminal metabolism and digestibility in cows fed perennial ryegrassEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2007Michel Doreau Abstract The ruminal metabolism and intestinal digestibility of fatty acids (FA) was studied in four mid-lactation dairy cows fitted with ruminal and duodenal cannulae. The cows received fresh perennial ryegrass as sole feed. Two grasses were compared, differing in the soluble carbohydrate/nitrogen ratio (SC+/N, and SC,/N+ ratios). This ratio was modified by the combination of three factors: age of regrowth, N,fertilisation and hour of cutting. The two grasses contained 12.5 and 20.7% of crude protein, and 24.6 and 13.7% of SC, respectively. The SC+/N, grass contained less FA [1.82 vs. 2.49% of dry matter (DM)] and a lower percentage of linolenic acid (60.9 vs. 65.6% of FA). As DM intake did not differ between treatments, FA intake was higher for the SC,/N+ treatment. The duodenal composition of FA revealed numerous isomers of 18:1 and conjugated and non-conjugated isomers of 18:2. SC,/N+ treatment resulted in a higher duodenal flow of stearic, linoleic, and linolenic acids and of several intermediates of linolenic acid hydrogenation. This was a consequence of differences in intake. Intestinal digestibility of FA from both grasses was high (around 90%). The proportions of FA in plasma did not reflect with accuracy the differences in duodenal FA resulting from differences in ruminal metabolism. [source] Structure and activity of the nitrate-reducing community in the rhizosphere of Lolium perenne and Trifolium repens under long-term elevated atmospheric pCO2FEMS MICROBIOLOGY ECOLOGY, Issue 3 2004Kathrin Deiglmayr Abstract Rhizosphere soil was sampled in monocultures of Lolium perenne and Trifolium repens in June and October 2002, at two different nitrogen fertilisation levels (14 and 56 g N m,2 year,1) and under two pCO2 atmospheres (360 and 600 ppmv) at the Swiss FACE (Free Air Carbon dioxide Enrichment) site. Directly extracted soil DNA was analysed with restriction fragment length polymorphism (PCR-RFLP) by use of degenerated primers for the narG gene encoding the active site of the membrane-bound nitrate reductase. The corresponding enzyme activity of the nitrate reductase was determined colorimetrically after 24 h of anaerobic incubation. The narG PCR-RFLP fingerprints showed that the structure of the nitrate-reducing community was primarily affected by season and pH of the sampling site, whereas CO2 enrichment, plant species or fertiliser treatment had no apparent effect. In contrast, the nitrate reductase activity responded to N fertilisation, CO2 enrichment and plant species in October, whereas in June drought stress most likely kept the enzyme activity at a low level in all treatments. Apparently, the respiratory nitrate-reducing community adapted to different treatments primarily by altered enzyme activity. [source] Depensation: evidence, models and implicationsFISH AND FISHERIES, Issue 1 2001Liermann We review the evidence supporting depensation, describe models of two depensatory mechanisms and how they can be included in population dynamics models and discuss the implications of depensation. The evidence for depensation can be grouped into four mechanisms: reduced probability of fertilisation, impaired group dynamics, conditioning of the environment and predator saturation. Examples of these mechanisms come from a broad range of species including fishes, arthropods, birds, mammals and plants. Despite the large number of studies supporting depensatory mechanisms, there is very little evidence of depensation that is strong enough to be important in a population's dynamics. However, because factors such as demographic and environmental variability make depensatory population dynamics difficult to detect, this lack of evidence should not be interpreted as evidence that depensatory dynamics are rare and unimportant. The majority of depensatory models are based on reduced probability of fertilisation and predator saturation. We review the models of these mechanisms and different ways they can be incorporated in population dynamics models. Finally, we discuss how depensation may affect optimal harvesting, pest control and population viability analysis. [source] The effect of nitrogen fertilization on fungistatic phenolic compounds in roots of beech (Fagus sylvatica) and Norway spruce (Picea abies)FOREST PATHOLOGY, Issue 4 2005L. Tomova Summary The effect of nitrogen fertilization on fungistatic phenolic compounds in fine roots of beech and Norway spruce growing in afforestation plots was analysed. The plots were situated at two sites in Switzerland on acidic soil with low base saturation. For 9 years, the trees have been treated with dry ammonium nitrate to give 0, 10, 20, 40, 80, 160 kg N ha,1 year,1, respectively. The phenolic compounds responded differently to fertilization. Fine roots of beech showed a significant decrease of (,)-epicatechin and piceatannol with increasing nitrogen fertilization. The concentration of protocatechuic acid was increased with fertilization. Roots of fertilized Norway spruce showed significantly decreased concentrations of 4-hydroxyacetophenone and piceatannol. The mycelial growth of three isolates each of Heterobasidion annosum s.l. and Cylindrocarpon destructans was tested on agar media containing various phenolic compounds in concentrations found in fine roots of Norway spruce (Picea abies) and beech (Fagus sylvatica). All three H. annosum isolates were inhibited by p-coumaric acid and (,)-epicatechin. Two isolates were inhibited by another four phenolic compounds (p-hydroxybenzoic acid, 4-hydroxyacetophenone, piceatannol and protocatechuic acid), one by (+)-catechin. Two of three C. destructans isolates were inhibited by all phenolic compounds except for (+)-catechin which affected only one isolate, one isolate did not respond at all. Résumé L'effet d'une fertilisation azotée sur les composés phénoliques fongistatiques des racines fines de Hêtre (Fagus sylvatica) et d'Epicea (Picea abies) a été analysé dans des parcelles de reboisement. Ces parcelles sont situées dans deux localités de Suisse sur sol acide, avec un faible taux de saturation en bases. Pendant neuf ans, les arbres ont été traités par apports secs de nitrate d'ammonium à raison de 0, 10, 20, 40, 80, 160 kg N par hectare et par an, respectivement. La réponse des composés phénoliques à la fertilisation est variable. Les racines fines de hêtres ont montré une baisse significative d'épicatèchine (,) et de piceatannol avec l'augmentation de la fertilisation azotée. Les concentrations d'acide protocatéchique ont augmenté avec la fertilisation. Les racines d'épicèas fertilisés ont montré une baisse significative des concentrations de 4-hydroxyacétophénone et de piceatannol. La croissance mycélienne de trois isolats de chacune des espèces H .annosum s.l. et Cylindrocarpon destructans a été testée sur milieu agar contenant les différents composés phénoliques aux concentrations trouvées dans les racines fines d'épicèas (Picea abies) et de hêtres (Fagus sylvatica). Les trois isolats d'Heterobasidion annosum s.l. ont été inhibés par l'acide p-coumarique et l'épicatèchine (,). Deux isolats ont été inhibés par quatre autres composés phénoliques (acide p-hydroxybenzoïque, 4-hydroxyacétophénone, piceatannol et acide protocatéchique) et un par la catéchine (+). Deux des trois isolats de Cylindrocarpon destructans ont été inhibés par tous les composés phénoliques à l'exception de la catéchine (+) pour l'un des deux, le dernier isolat ne répondant à aucun composé. Zusammenfassung In einer Aufforstungs-Versuchsfläche wurde der Einfluss einer Stickstoffdüngung auf die fungistatischen phenolischen Verbindungen in Feinwurzeln von jungen Buchen und Fichten untersucht. Die Versuchsflächen befanden sich an zwei Standorten in der Schweiz mit sauren, basenarmen Bodenverhältnissen. Die Bäume wurden über neun Jahre mit 0, 10, 20, 40, 80 und 160 kg N ha,1 a,1 in Form von Ammoniumnitrat gedüngt. Die phenolischen Verbindungen reagierten unterschiedlich auf die Düngung. Die Feinwurzeln von Buchen zeigten mit zunehmender Stickstoffdüngung eine signifikante Abnahme von (,) Epicatechin und Piceatannol, während die Konzentration von Protocatechinsäure durch die Düngung erhöht wurde. Die Feinwurzeln gedüngter Fichten wiesen ebenfalls signifikant tiefere Konzentrationen von 4-Hydroyacetophenon und Piceatannol auf. In in-vitro-Tests wurde das Myzelwachstum von allen drei geprüften Isolaten von Heterobasidion annosum s. l. durch die in den Wurzeln gefundenen Konzentrationen von p-Coumarinsäure und (,)Epicatechin gehemmt. Zwei Pilzisolate zeigten zudem eine Hemmung durch vier weitere in den Wurzeln gefundene phenolische Verbindungen, nämlich p-Hydroxybenzoesäure, 4-Hydroxyacetophenon, Piceatannol und Protocatechinsäure, und eines wurde auch durch (+)-Catechin gehemmt. Bei zwei von drei geprüften Isolaten von Cylindrocarpon destructans wurde das Myzelwachstum durch alle untersuchten phenolischen Verbindungen gehemmt, mit Ausnahme von (+)-Catechin, welches sich nur auf ein Isolat negativ auswirkte. Ein Isolat von C. destructans reagierte auf keine der genannten Substanzen. [source] Changes in abundance, composition and controls within the plankton of a fertilised arctic lakeFRESHWATER BIOLOGY, Issue 2 2002Neil D. Bettez 1. An oligotrophic arctic lake was fertilised with inorganic nitrogen and phosphorus as (NH4)2 NO3 and H3PO4 for five summers. The loading rate was 1.7,2.5 mmol N m,2 day,1 and 0.136,0.20 mmol P m,2 day,1 which is two to three times the annual loading of lakes in the area. The heterotrophic microzooplankton community was enumerated during the experiment as well as 1 year pre- and post-treatment. 2. The structure of the microplankton community changed from a nutrient limited system, dominated by oligotrich protozoans and small-particle feeding rotifers, to a system dominated by a succession of peritrich protozoans and predatory rotifers. These peritrich protozoans and predatory rotifers were not present prior to fertilisation and never constituted more than a small fraction of the biomass in other lakes at the research site. The average biomass of the rotifers and protozoans was more than seven and a half times larger by the end of fertilisation than it was initially. 3. Because of the increases in numbers of individuals in these new taxa, the structure of the microbial food web changed. When fertilisation stopped, most parameters returned to prefertilisation levels within 1 year. [source] Nitrogen and the Colour of the CropsGERMAN RESEARCH, Issue 2-3 2002Hermann J. Heege Prof. em. To each plant its due: An optical sensor on the fertiliser distributor uses leaf colouring to determine the corn's nitrogen requirement. This restricts fertilisation to actual requirements [source] Shading delays bud break in Brachsyegia spiciformisAFRICAN JOURNAL OF ECOLOGY, Issue 4 2008R. A. Richer Abstract Whole tree manipulation experiments were performed in the common southern African tree species, Brachystegia spiciformis to test a novel hypothesis that decreasing Total nonstructural carbohydrates (TNC) in the stem could cause bud break in Brachystegia spiciformis. The experimental treatments included fertilization, canopy defoliation, shading and stem heating to decrease stem carbohydrates. None of the treatments significantly decreased mean stem TNC. Likewise the heating, fertilization and defoliation treatments did not significantly affect the date of bud break. However, shading significantly delayed bud break. This delay in bud break could not be attributed to changes in leaf level photosynthetic traits, stem water content, leaf predawn water potential or delayed leaf fall. These results question widely accepted hypotheses about the mechanisms controlling bud break and suggest a carbohydrate homeostatic mechanism. Résumé Des expérimentations de manipulations d'arbres très complètes ont été réalisées sur l'espèce très commune en Afrique du Sud Brachystegia spiciformis pour tester une nouvelle hypothèse selon laquelle une diminution des TNC, les hydrates de carbone nonstructuraux, dans le tronc pourrait causer l'éclosion des bourgeons chez cette espèce. Les traitements expérimentaux comprenaient une fertilisation, le défeuillage de la canopée, la mise à l'ombre ou le chauffage des troncs pour diminuer les hydrates de carbone. Aucun de ces traitements n'a diminué significativement les TNC dans les troncs. Le chauffage, la fertilisation ou le défeuillage n'ont pas non plus affecté la date de l'éclatement des bourgeons. Le fait d'être à l'ombre a, par contre, significativement retardé l'éclosion des bourgeons. Ce retard ne pouvait pas être attribué aux changements du taux de photosynthèse des feuilles, à la teneur en eau des troncs, au potentiel aqueux des feuilles avant l'aube, ni au retard de la chute des feuilles. Ces résultats remettent en question les hypothèses largement acceptées au sujet des mécanismes qui contrôlent l'éclosion des bourgeons et suggèrent l'existence d'un mécanisme homéostatique lié aux hydrates de carbone. [source] Effects of organic fertilisers and irrigation level on physical and chemical quality of industrial tomato fruit (cv. Nautilus)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2009Ramón Madrid Abstract BACKGROUND: The objective of this work was to study the influence of irrigation and organic fertilisation on quality attributes of tomato fruit (cv. Nautilus) grown for the canning industry. The assay was carried out during two consecutive years (2006 and 2007) in agricultural soil. Nine treatments resulting from the combination of three fertilisation types (sheep manure, a mixture of sheep manure and peat and an inorganic fertiliser (control)) with three levels of drip irrigation (3.30, 5.00 and 6.70 mm day,1) under black polyethylene mulch were applied (n = 3). RESULTS: For the chromatic attributes L*, H*, C* and S* the highest values corresponded to the treatments with organic matter. However, the a*/b* ratio and colour index value were higher for the control treatment. In all cases the estimated optimal ripening time was the same, and on this date a decline in the ratios was observed. The values of the physical properties increased with increasing irrigation, higher values always being obtained in the treatments with organic fertilisers. The highest production for all irrigation levels corresponded to the treatment with mixed sheep manure and peat fertiliser. CONCLUSION: Cultivation involving fertilisation with the manure/peat mixture and an irrigation level slightly above 5.00 mm day,1 can be recommended as optimal, since it gave the most satisfactory values with respect to the quality attributes of tomato fruit grown for the canning industry. Copyright © 2009 Society of Chemical Industry [source] Quantification of uncertainty using Bayesian and bootstrap models to simulate the impact of nitrogen fertilisation on ,-glucan levels in barleyJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2009Marta Fontana Abstract BACKGROUND: ,-Glucans have enjoyed renewed interest as a functional food ingredient, with current attention focused on optimising ,-glucan levels in finished products without compromising final product quality. In order to measure the uncertainty about the level of ,-glucans in barley, two different statistical methods (Bayesian inference and Bootstrap technique) were applied to measured levels of ,-glucan in three different varieties of barley grain (n = 83). RESULTS: The resulting probability density distributions were similar for the full data set and also when applied to smaller sample sizes, highlighting the potential for either method in quantifying the total uncertainty in ,-glucan levels. Bayesian inference was used to model the effect of nitrogen treatment on ,-glucan and protein contents in barley. The model found that a low level of fertilisation (50 kg N ha,1) did not have a significant effect on ,-glucan or protein content. However, fertilisation above this level did result in an increase in ,-glucan and protein levels, the effect seeming to plateau at 100 kg N ha,1. In addition, the uncertainty distributions were significantly different for two consecutive years of data, highlighting the potential environmental influence on ,-glucan content. CONCLUSION: The model developed in this study could be a useful tool for processors to quantify the uncertainty about the initial level of ,-glucan in barley and to evaluate the influence of environmental factors, thus enabling them to formulate their ingredient base to optimise levels of ,-glucan without compromising final product quality. Copyright © 2009 Society of Chemical Industry [source] Antioxidant compounds in green and red peppers as affected by irrigation frequency, salinity and nutrient solution compositionJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2009Alicia Marín Abstract BACKGROUND: There is a need to encourage more sustainable agricultural practices, reducing inputs of water and fertilisers while minimising any negative impact on fruit quality. The effect of irrigation frequency, salinity and potassium and calcium fertilisation on the content of bioactive compounds and quality attributes of green and red peppers grown with and without substrate was evaluated. RESULTS: Low irrigation frequency and salinity improved the quality attributes (dry matter, soluble solids content and titratable acidity) of pepper. Low irrigation frequency increased vitamin C content by 23% in green peppers, while in red fruits it was not affected. In contrast, total carotenoids and provitamin A only increased in red fruits by 30% and 15%, respectively, as a consequence of low irrigation frequency. When the effect of potassium and calcium doses was investigated, it was shown that a high proportion of potassium increased the vitamin C, provitamin A and total phenolic content of red and green peppers, whereas pepper grown at low calcium doses, presented the highest content in carotenoids and provitamin A. CONCLUSION: Low irrigation frequency and fertilisation with high potassium and low calcium doses improved pepper quality increasing the content of bioactive compounds. Copyright © 2009 Society of Chemical Industry [source] Nitrogen fertilisation in coriander (Coriandrum sativum L.): a review and meta-analysisJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2009Alessandra Carrubba Abstract Nitrogen (N) fertilisation is one of the most important external inputs in assessing coriander seed yield and plant growth. Recent concerns related to the misuse of N fertilisers in agricultural environments, however, stress the opportunity for a fine-tuning of N management in order to optimise the use of this element, avoiding losses and reducing environmental hazards. In this study, some results from the literature concerning N fertilisation in coriander are reviewed and, by means of statistical analysis, an attempt is made to derive from them some general suggestions about practices of N fertilisation. In most cases examined, N fertilisation allowed a 10,70% increase in seed yields in comparison with each respective untreated control. The efficiency of use of this element, however, has proven to be greatly dependent on the overall fertility conditions of the growing site. The greatest yield advantages were actually found in more favourable environments, whereas in low-yielding environments plants reached their maximum yield with a comparatively reduced N supply. In low-yielding environments a careful risk/benefit assessment of this practice is therefore advisable. No definite conclusion could be drawn at this stage about essential oil yield and composition in relation to N fertilisation. Copyright © 2009 Society of Chemical Industry [source] Brassica oleracea var. costata: comparative study on organic acids and biomass production with other cabbage varietiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2009Carla Sousa Abstract BACKGROUND: A study was undertaken to evaluate the effect of agronomic practices, harvesting time and leaf age on the organic acid composition and biomass production of Brassica oleracea L. var. costata DC (tronchuda cabbage). Samples were cultivated under eight different fertilisation regimes (two levels each of nitrogen, boron and sulfur, an organic fertiliser and no fertiliser) and collected at three different times. RESULTS: Principal component analysis of the data indicated significant differences. Three principal components with an eigenvalue higher than one accounted for 79.0% of the total variance of the data set. Samples obtained with conventional fertilisation were characterised by the highest values of fresh weight. External leaves showed higher total organic acid and malic acid contents than internal leaves, while the latter were characterised by higher proportions of citric acid. For consecutive harvests, total organic acid concentration decreased in both external and internal leaves. CONCLUSION: The use of a conventional fertilisation regime (nitrogen, boron or sulfur) improved the growth of B. oleracea var. costata without affecting its organic acid profile. However, for consecutive harvests, total organic acid concentration was observed to decrease independently of the agronomic practices tested. Leaf age influenced the quantitative composition of organic acids. Copyright © 2009 Society of Chemical Industry [source] On fumonisin incidence in monoculture maize under no-till, conventional tillage and two nitrogen fertilisation levelsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2008Adriano Marocco Abstract BACKGROUND:Fusarium ear rot and fumonisin contamination are serious problems for maize growers. The lack of maize genotypes highly resistant to fumonisin contamination emphasises the need for management strategies to prevent contamination by this mycotoxin. There are conflicting reports regarding no-till and nitrogen (N) fertilisation practices in relation to the incidence of fumonisins. In this study the effect of no-till compared with conventional tillage and of N fertilisation rates on fumonisin occurrence was investigated over three years in Northern Italy. RESULTS: The average contamination of grain by fumonisins B1 and B2 over the three years was significantly different, with a lower value in 2000 (516 µg kg,1) than in the other years (5846 and 3269 µg kg,1 in 2001 and 2002 respectively). Conventional tillage and no-till treatments had no significant effect on the incidence of fumonisins. This finding suggests that above-ground residues infected by Fusarium would not lead to an increase in fumonisin incidence. However, N fertilisation significantly increased fumonisin levels, by 99 and 70% in 2000 and 2001 respectively. CONCLUSION: Maize monoculture does not show a cumulative effect on the occurrence of fumonisins, while high rates of N fertiliser consistently result in elevated fumonisin levels. Both these effects can be influenced by annual meteorological fluctuations. Copyright © 2008 Society of Chemical Industry [source] Effect of nitrogen fertilisation on below-ground carbon allocation in lettuceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2002Y Kuzyakov Abstract The aims of this study were to investigate the effect of nitrogen (N) fertilisation on the below-ground carbon (C) translocation by lettuce and the CO2 efflux from its rhizosphere. Two N fertilisation levels (80 and 160,kg N,ha,1) and two growth stages (43 and 60 days) were tested. 14C pulse labelling of shoots followed by 14C monitoring in the soil, roots, microbial biomass and CO2 efflux from the soil was used to distinguish between root-derived and soil organic matter-derived,C. The 14C allocation in the below-ground plant parts was 1.5,4.6 times lower than in the leaves. The total quantity of C translocated into the soil was much lower than in the case of cereals and grasses, amounting to 120 and 160,kg C,ha,1 for low and high N respectively. N fertilisation diminished the proportion of assimilated C translocated below ground. About 5,8% of the assimilated C was respired into the rhizosphere. Root-derived CO2 (the sum of root respiration and rhizomicrobial respiration) represented about 15,60% of the total CO2 efflux from the planted soil. Two peaks were measured in the 14CO2 efflux: the first peak (4,5,h after labelling) was attributed to root respiration, whilst the second peak (12,h after labelling) was attributed to microbial respiration of exudates. Twelve days after labelling, 0.15,0.25% of the assimilated C was found in the microbial biomass. The higher microbial activity in the lettuce rhizosphere doubled the soil organic matter decomposition rate compared with unplanted soil. © 2002 Society of Chemical Industry [source] Factors influencing anthocyanin content in red cabbage (Brassica oleracea var capitata L f rubra (L) Thell)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2002Roberta Piccaglia Abstract In North and Central Italy an experiment was conducted for two consecutive years to optimise the anthocyanin yield of red cabbage. Two hybrids (,Roxy' and ,Gradur') were grown under a factorial combination of increasing rates of potassium sulphate (0, 50, 100,kg K ha,1) and superphosphate (0, 39, 78,kg P ha,1) applied before planting. Cabbages were transplanted at the beginning of August and harvested in winter. Anthocyanins were extracted from cabbage heads with HCl in methanol (1% v/v solution) and quantified by absorption spectrophotometry at 530,nm. Results showed that red cabbage can give high yields of anthocyanins (more than 90,kg,ha,1) which are characterised by strong acylation and therefore, presumably, by good stability. However, differences over sites and years were marked. In the first year, yields in North Italy were reduced by a heavy infection of soft rot disease. The choice of variety, linked to a different anthocyanin content in the heads, appeared to be the major factor for a successful crop. P and K fertilisation had only a small influence. On clay soils in Central Italy the highest rates of both elements had a negative effect on the anthocyanin concentration in cabbage heads. © 2002 Society of Chemical Industry [source] Sodium selenate fertilisation increases selenium accumulation and decreases glucosinolate concentration in rapid-cycling Brassica oleraceaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2001Craig S Charron Abstract Glucosinolates (GSs) are S-containing compounds found in Brassica species and whose degradation products may provide protection against cancer. Sulphoraphane, a product of 4-methylsulphinylbutyl GS degradation, is a particularly potent inhibitor of anticarcinogenic detoxification enzymes. Selenium also has anticancer properties, and consumption of plants containing Se may be an effective way to increase dietary Se. Since plant uptake of Se and S is competitive, GS synthesis may be affected by Se fertilisation. The objective of this study was to determine how Se fertilisation of rapid-cycling B oleracea would affect Se and GS concentrations. Plants were grown in hydroponic solutions containing 0.0, 1.0, 2.0, 3.0, 6.0, 7.2 or 9.0,mg,l,1 Na2SeO4. Mineral and glucosinolate concentrations were measured in shoots harvested just before anthesis. Total GSs decreased from 5.84,µmol,g,1 (0.0,mg,l,1 Na2SeO4) to 1.90,µmol,g,1 (9.0,mg,l,1Na2SeO4). Levels of 4-methylsulphinylbutyl GS decreased 90% when Na2SeO4 fertilisation was increased from 0 to 1,mg,l,1, and remained low at higher Na2SeO4 concentrations. Shoot Se concentration was undetectable at 0.0,mg,l,1 Na2SeO4 and increased significantly with Na2SeO4 fertilisation. Although B oleracea may not simultaneously deliver high levels of dietary 4-methylsulphinylbutyl GS and Se, levels of other GSs with anticarcinogenic benefits may be beneficial even with Se fertilisation. © 2001 Society of Chemical Industry [source] Flood events overrule fertiliser effects on biomass production and species richness in riverine grasslandsJOURNAL OF VEGETATION SCIENCE, Issue 5 2007Boudewijn Beltman Abstract Question: Do severe winter flood events lift the nutrient limitation of biomass production in a river floodplain? How does this affect plant species richness? How long do the effects last? Location: Floodplain grassland on calcareous sandy loam near river Rhine in The Netherlands. Methods: Plots were fertilised with four treatments (control, N, P, N+P) for 21 years; plant species composition, vegetation biomass and tissue nutrient concentrations were determined every year between 1985 and 2005. Results: Fertilisation with N generally increased biomass production and reduced species richness, but these effects varied over time. During the first four years of the experiment, biomass production appeared to be co-limited by N and P, while N fertilisation dramatically reduced plant species richness; these effects became weaker subsequently. Following two extreme winter floods in 1993,94 and 1994,95 and a drought in spring 1996, the effects of fertilisation disappeared between 1998 and 2001 and then appeared again. Flooding caused an overall reduction in species richness (from c. 24 to 15 species m -2) and an increase in biomass production, which were only partly reversed after ten years. Conclusions: Long time series are necessary to understand vegetation dynamics and nutrient limitation in river floodplains, since they are influenced by occasional flood and drought events, whose effects may persist for more than ten years. A future increase in flooding frequency might be detrimental to species richness in floodplain grasslands. [source] Altered mRNA expression patterns in bovine blastocysts after fertilisation in vitro using flow-cytometrically sex-sorted spermMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 8 2007K.M. Morton Abstract Sperm-sexing has been used to produce embryos and offspring of a pre-determined sex in a number of species. However, the fertility of sex-sorted sperm is reduced and the full effects of sperm-sexing remain to be elucidated. The purpose of the present study was to investigate the potential effects of sex-sorted sperm on mRNA expression patterns of developmentally important genes employing in vitro produced bovine embryos. Bovine embryos were produced in vitro with unsorted and sex-sorted sperm and mRNA expression patterns were determined for glucose-3 transporter (Glut-3), glucose-6-phosphate dehydrogenase (G6PD), X-inactive specific transcript (X-ist) and Heat shock protein 70.1 (Hsp) using semi-quantitative endpoint reverse transcriptase-PCR in male and female, day-7 and 8 embryos. The relative abundance (RA) of Glut-3 was higher for day-7 male than female embryos, and day-7 embryos derived from unsorted compared with sex-sorted sperm. The RA of G6PD was higher for embryos derived from unsorted than sex-sorted sperm, and for day-8 female compared with male embryos. The RA of Xist was higher for female than male embryos, and for day-7 female embryos derived from unsorted than sex-sorted sperm. Hsp RA was higher for female compared with male embryos, was similar for day-7 and 8 embryos, and unsorted and sex-sorted sperm derived embryos. These results demonstrate differential expression of developmentally important genes between male and female embryos, and embryos derived from unsorted and sex-sorted sperm. Mol. Reprod. Dev. 74: 931,940, 2007. © 2007 Wiley-Liss, Inc. [source] Top-down and bottom-up control in an eelgrass,epiphyte systemOIKOS, Issue 5 2008Sybill Jaschinski Nutrient supply and the presence of grazers can control primary producers in aquatic ecosystems, but the relative importance of bottom-up and top-down effects remains inconclusive. We conducted a mesocosm experiment and a field study to investigate the independent and interactive effects of nutrient enrichment and grazing on primary producers in an eelgrass bed Zostera marina. Nutrient treatments consisted of ambient or enriched (2× and 4× ambient) concentrations of inorganic nitrogen and phosphate. Grazer treatments consisted of presence or absence of field densities of the common isopod Idotea baltica. We found strong and interacting effects of nutrients and grazing on epiphytes. Epiphyte biomass and productivity were enhanced by nutrient enrichment and decreased in the presence of grazers. The absolute amount of epiphyte biomass consumed by grazers increased under high nutrient supply, and thus, nutrient effects were stronger in the absence of grazing. The effects of grazers and fertilisation on epiphyte composition were antagonistic: chain-forming diatoms and filamentous algae profited from nutrient enrichment, but their proportions were reduced by grazing. Eelgrass growth was positively affected by grazing and by nutrient enrichment at moderate nutrient concentrations. High nutrient supply reduced eelgrass productivity compared to moderate nutrient conditions. The monthly measured field data showed a nitrogen limitation for epiphytes and eelgrass in summer, which may explain the positive effect of nutrient enrichment on both primary producers. Generally, the field data suggested the possibility of seasonally varying importance of bottom-up and top-down control on primary producers in this eelgrass system. [source] An analysis of hatching success in the great reed warbler Acrocephalus arundinaceusOIKOS, Issue 3 2008Jonas Knape Hatching success is a potentially important fitness component for avian species. Previous studies of hatching success in natural populations have primarily focused on effects of inbreeding but a general understanding of variation in hatching success is lacking. We analyse data on hatching success in a population of great reed warblers Acrocephalus arundinaceus in Lake Kvismaren in south central Sweden. The effects of a range of covariates, including three measures of inbreeding as well as effects of classifications in the data (such as identities of individuals), on hatching success are analysed simultaneously. This is done by means of fitting Bayesian binomial mixed models using Markov chain Monte Carlo methods. Using random effects for each individual parent we check for unexplained variation in hatching success among male and female individuals and compare it to effects of covariates such as degree of inbreeding. Model selection showed that there was a significant amount of unexplained variation in hatching probability between females. This was manifested by a few females laying eggs with a substantially lower hatching success than the majority of the females. The deviations were of the same order of magnitude as the significant effect of parent relatedness on hatching success. Whereas the negative effect of parent relatedness on hatchability is an expression of inbreeding, the female individual effect is not due to inbreeding and could reflect maternal effects, that females differ in fertilisation and/or incubation ability, or an over representation of genetic components from the female acting on the early developing embryo. [source] Estimation of the day-specific probabilities of conception: current state of the knowledge and the relevance for epidemiological researchPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 2006Courtney D. Lynch Summary Conception, as defined by the fertilisation of an ovum by a sperm, marks the beginning of human development. Currently, a biomarker of conception is not available; as conception occurs shortly after ovulation, the latter can be used as a proxy for the time of conception. In the absence of serial ultrasound examinations, ovulation cannot be readily visualised leaving researchers to rely on proxy measures of ovulation that are subject to error. The most commonly used proxy measures include: charting basal body temperature, monitoring cervical mucus, and measuring urinary metabolites of oestradiol and luteinising hormone. Establishing the timing of the ovulation and the fertile window has practical utility in that it will assist couples in appropriately timing intercourse to achieve or avoid pregnancy. Identifying the likely day of conception is clinically relevant because it has the potential to facilitate more accurate pregnancy dating, thereby reducing the iatrogenic risks associated with uncertain gestation. Using data from prospective studies of couples attempting to conceive, several researchers have developed models for estimating the day-specific probabilities of conception. Elucidating these will allow researchers to more accurately estimate the day of conception, thus spawning research initiatives that will expand our current limited knowledge about the effect of exposures at critical periconceptional windows. While basal body temperature charting and cervical mucus monitoring have been used with success in field-based studies for many years, recent advances in science and technology have made it possible for women to get instant feedback regarding their daily fertility status by monitoring urinary metabolites of reproductive hormones in the privacy of their own homes. Not only are innovations such as luteinising hormone test kits and digital fertility monitors likely to increase study compliance and participation rates, they provide valuable prospective data that can be used in epidemiological research. Although we have made great strides in estimating the timing and length of the fertile window, more work is needed to elucidate the day-specific probabilities of conception using proxy measures of ovulation that are inherently subject to error. Modelling approaches that incorporate the use of multiple markers of ovulation offer great promise to fill these important data gaps. [source] Biomarkers of ovulation, endometrial receptivity, fertilisation, implantation and early pregnancy progressionPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 2006Kenneth L. Campbell Summary Increasing interest in early preconception and periconception exposures and human developmental outcomes has led to studies that monitor subjects from before conception to gestation, birth and childhood. Monitoring ovulation, endometrial receptivity, fertilisation, implantation and gestation requires the non-invasive collection of biological information and samples, and the measurement of biochemical and biological markers (biomarkers) that are associated with the aforementioned physiological events. This paper describes some of the key features of biomarkers needed for epidemiological studies, identifies some existing and potential biomarkers and available measurement devices, and suggests some directions for identification and development of new biomarkers that might be employed in longitudinal studies involving the analysis of female reproductive function and of embryonic development. [source] Factors influencing twins and zygosityPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 2005Gary V. D. Hankins Summary Zygosity is influenced by many factors. Monozygotic twins occur spontaneously in approximately 1 in 250 births and are felt to increase twofold with ovulation induction techniques. Monozygotic twinning also increases in proportion to the number of blastocysts transferred during in vitro fertilisation. In contrast, dizygotic twinning appears to be influenced by race, genetic factors, maternal age, fertility enhancing drugs, folic acid supplementation, and maternal nutritional status. [source] | ||||||||||||||||||||||||||||||||||