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Põldma P Tõnutare T Viitak A Luik A Moor U 《Journal of agricultural and food chemistry》2011,59(10):5498-5503
Foliar selenium (Se) treatment of garlic at concentrations of 10, 50, and 100 μg of Se/mL was carried out in open field conditions in 2008 and 2009 in Estonia. Bulb weight and yield structure, content of total Se, S, N, P, K, Ca, and Mg, ascorbic acid content (AAC), pungency, total phenolics, and total antioxidant capacity (TAC) were determined. The highest level of Se decreased total S, K, and Ca in both years; no negative impact on bulb weight was observed. In 2009 Se10 treatment had significantly more bulbs with the largest diameter compared to the other treatments. In 2008, the AAC was decreased by Se50 and the content of total phenolics by all Se treatments; however, TAC was increased. Foliar Se fertilization of garlic at rates of 10-50 μg of Se/mL can be recommended to increase the number of large bulbs and increase bulb antioxidant capacity. 相似文献
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Energy acquisition and allocation to egg production in relation to fish reproductive strategies 
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下载免费PDF全文 Richard S McBride Stylianos Somarakis Gary R Fitzhugh Anu Albert Nathalia A Yaragina Mark J Wuenschel Alexandre Alonso‐Fernández Gualtiero Basilone 《Fish and Fisheries》2015,16(1):23-57
Oogenesis in fishes follows a universal plan; yet, due to differences in the synchrony and rate of egg development, spawning frequency varies from daily to once in a lifetime. Some species spawn and feed in separate areas, during different seasons, by storing energy and drawing on it later for reproduction (i.e. capital breeding). Other species spawn using energy acquired locally, throughout a prolonged spawning season, allocating energy directly to reproduction (i.e. income breeding). Capital breeders tend to ovulate all at once and are more likely to be distributed at boreal latitudes. Income breeding allows small fish to overcome allometric constraints on egg production. Income breeders can recover more quickly when good‐feeding conditions are re‐established, which is a benefit to adults regarding bet‐hedging spawning strategies. Many species exhibit mixed capital‐ and income‐breeding patterns. An individual's position along this capital–income continuum may shift with ontogeny or in relation to environmental conditions, so breeding patterns are a conditional reproductive strategy. Poor‐feeding environments can lead to delayed maturation, skipped spawning, fewer spawning events per season or fewer eggs produced per event. In a few cases, variations in feeding environments appear to affect recruitment variability. These flexible processes of energy acquisition and allocation allow females to prioritize their own condition over their propagules' condition at any given spawning opportunity, thereby investing energy cautiously to maximize lifetime reproductive value. These findings have implications for temporal and spatial sampling designs, for measurement and interpretation of fecundity, and for interpreting fishery and ecosystem assessments. 相似文献
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Increased interest in marine resources has led to increased screening of marine fungi for novel bioactive compounds and considerable effort is being invested in discovering these metabolites. For compound discovery, small-scale cultures are adequate, but agitated bioreactors are desirable for larger-scale production. Calcarisporium sp. KF525 has recently been described to produce calcaride A, a cyclic polyester with antibiotic activity, in agitated flasks. Here, we describe improvements in the production of calcaride A in both flasks (13-fold improvement) and stirred bioreactors (200-fold improvement). Production of calcaride A in bioreactors was initially substantially lower than in shaken flasks. The cultivation pH (reduced from 6.8 to <5.4), carbon source (sucrose replacing glucose), C/N ratio and nature of mycelial growth (pellets or filaments) were important in improving calcaride A production. Up to 4.5 mg·g−1 biomass (85 mg·L−1) calcaride A were produced in the bioreactor, which was only slightly less than in shaken flasks (14 mg·g−1, 100 mg·L−1). The results demonstrate that a scalable process for calcaride A production could be developed using an iterative approach with flasks and bioreactors. 相似文献
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The ninety crosses were evaluated for 27 qualitative and quantitative traits to study the different gene actions, genetic variances, heritability and genetic advances involved in parents and in their off springs. The analysis of variance showed highly significant differences present among all the treatments for all quantitative and qualitative traits. The estimates of genetic component of variances together with related genetic parameters indicated that the magnitude of SCA variances was more pronounced than their corresponding GCA variances for majority of the traits for all testers and lines in both generations which suggested the role of non-additive gene action in the inheritance of these traits. The information obtained from the present study exhibited most of the traits had high value of σ2s than σ2g and over dominance gene action so, it is necessary to maintain the heterozygosity in the population for the improvement purposes. The non-additive genetic variability is non-fixable in nature thus the breeding methods such as biparental mating followed by recurrent selection may accelerate the genetic improvement for the traits sought to be improved. 相似文献
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V. Anuradha K. Byju Kala Jacob Anu Gopinath K. J. Prashob Peter T. R. Gireesh Kumar 《Journal Of Aquatic Food Product Technology》2013,22(7):639-647
The variation of the proximate composition and mineral content of nine seaweeds available in the Lakshadweep group of islands were studied to evaluate their nutritional quality. The proximate composition and the mineral contents were determined as per standard methodologies. The nutritional quality was found to be comparable with common vegetables and fruits. Hansen’s nutritional quality index has shown the seaweeds U. lactuca, H. valentea, and H. muciformis, in particular, to be safe for their versatile use and that they can contribute to a healthy balanced diet. 相似文献
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Riikonen J Kets K Darbah J Oksanen E Sober A Vapaavuori E Kubiske ME Nelson N Karnosky DF 《Tree physiology》2008,28(2):243-254
Paper birch (Betula papyrifera Marsh.) and three trembling aspen clones (Populus tremuloides Michx.) were studied to determine if alterations in carbon gain in response to an elevated concentration of CO(2) ([CO(2)]) or O(3) ([O(3)]) or a combination of both affected bud size and carbohydrate composition in autumn, and early leaf development in the following spring. The trees were measured for gas exchange, leaf size, date of leaf abscission, size and biochemical characteristics of the overwintering buds and early leaf development during the 8th-9th year of free-air CO(2) and O(3) exposure at the Aspen FACE site located near Rhinelander, WI. Net photosynthesis was enhanced 49-73% by elevated [CO(2)], and decreased 13-30% by elevated [O(3)]. Elevated [CO(2)] delayed, and elevated [O(3)] tended to accelerate, leaf abscission in autumn. Elevated [CO(2)] increased the ratio of monosaccharides to di- and oligosaccharides in aspen buds, which may indicate a lag in cold acclimation. The total carbon concentration in overwintering buds was unaffected by the treatments, although elevated [O(3)] decreased the amount of starch by 16% in birch buds, and reduced the size of aspen buds, which may be related to the delayed leaf development in aspen during the spring. Elevated [CO(2)] generally ameliorated the effects of elevated [O(3)]. Our results show that both elevated [CO(2)] and elevated [O(3)] have the potential to alter carbon metabolism of overwintering buds. These changes may cause carry-over effects during the next growing season. 相似文献
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Koponen JM Happonen AM Auriola S Kontkanen H Buchert J Poutanen KS Törrönen AR 《Journal of agricultural and food chemistry》2008,56(9):3136-3144
The fate of black currant ( Ribes nigrum L.) and bilberry ( Vaccinium myrtillus L.) flavonols in enzyme-aided processing was studied. The flavonols were quantified and characterized by high-performance liquid chromatography equipped with a diode array detector and an electrospray ionization mass spectrometer. A tentative identification for 14 black currant and 19 bilberry flavonols is presented representing 11 previously unpublished conjugates. For the first time in any berry, the presence of laricitrin conjugates is reported. The enzyme-aided processing affected the flavonol extractability, elevating the yield in juices and decreasing that in press residues. Importantly, no significant loss of the berry flavonols was observed during the experiments, although some hydrolysis of flavonol conjugates was recorded. To maximize the effect on flavonol extractability, higher enzyme dosages were needed for black currants than for bilberries. The data show that the flavonol extractability and hydrolysis are dependent on the texture of raw material, the glycosylation pattern of the conjugates, and the activity profile of the enzyme preparation. 相似文献
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Kaisa Heimonen Anu Valtonen Sari Kontunen-Soppela Sarita Keski-Saari Matti Rousi Elina Oksanen 《Scandinavian Journal of Forest Research》2017,32(2):95-104
Susceptibility of trees to herbivorous insects is often associated with the tree growth and phenology, both of which are sensitive to a warming climate. Therefore, changes in these traits may affect the intensity of herbivory on trees in the future. We grew silver birch (Betula pendula) populations differing in their growth and phenology in a common garden experiment, and studied the effect of these plant traits on the leaf herbivory, insect herbivore density and community composition of herbivores in two consecutive years, 2011 and 2012. Differences in size and the timing of growth cessation among the birch genotypes were related to differences in herbivore community compositions and herbivory. In 2011, the most intensive herbivore damage was observed on birch genotypes of small size, late bud burst and early growth cessation, and these genotypes originated from high-latitude populations. The differences among birch genotypes in their susceptibility to herbivore damage may lead to differences in their competitive abilities. While climate warming will affect phenology and growth of plants, our study shows, that it may indirectly affect herbivory and herbivore communities as well. 相似文献