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151.
Hot water extractable C and N in relation to microbiological properties of soils under beech forests
Marcin?ChodakEmail author Partap?Khanna Friedrich?Beese 《Biology and Fertility of Soils》2003,39(2):123-130
Hot water extraction is sometimes recommended as an easy method to estimate the readily mineralizable fractions of total C (Ct) and total N (Nt) in arable soils. However, the usefulness of this method for forest soils has not been adequately studied. The objectives of this study were to relate the hot water extractable C (Chw) and N (Nhw) to microbiological and chemical properties of the forest soils under beech (Fagus sylvatica L.) stands and to test the ability of near infrared spectroscopy (NIRS) to predict chemical and microbial properties of these soils. Soils differing in humus type, soil type and soil texture were collected from five locations and five depths. In all soils the amount of Chw was higher than the microbial biomass C (Cmic) indicating that a considerable part of Chw was of non-microbial origin. The amount of Chw in mineral soil correlated significantly (r =–0.30–0.53) with Cmic, basal respiration (BAS) and Ct/Nt ratio but was not related to Cmic/Ct ratio. The amount of Nhw was correlated with Cmic, BAS, Cmic/Ct ratio, and Ct/Nt ratio (r =–0.59–0.78). However, Ct and Nt values showed better relationships (r =–0.42–0.88) with all the parameters, indicating no advantage in using Chw and Nhw in forest soils. NIRS predicted satisfactorily Ct, Nt, Chw, Nhw, Cmic, Cmic/Ct ratio and BAS in the mineral soils [the regression coefficients (a) of linear regression (measured against predicted values) ranged from 0.84 to 1.17 and the correlation coefficients (r) ranged from 0.86 to 0.94] indicating the applicability of NIRS to estimate these properties. 相似文献
152.
Selection of parental lines is important in plant breeding programmes. Marker-assisted selection is an alternative to classical
selection methods, which are expensive and time consuming. Marker-assisted selection aims to find molecular markers that are
linked to genes that determine quantitative traits of interest. Classical statistical methods require particular assumptions
to be fulfilled, which is difficult to check if the analyses are performed automatically. In this article, we present a heuristic
method to find interesting markers for quantitative traits. This method includes various strategies that depend on what makes
a genotype interesting to a plant breeder. This approach was applied to eighteen parental lines of winter oilseed rape F1 CMS ogura hybrids with observation of 597 markers. The traits of interest were seed yield and alkenyl glucosinolate content. Fifty-seven
markers were selected for further study. The most prominent marker was OPY 02~1830. Marker-assisted selection is the first
step of analysis, which can then be followed up by a more formal statistical analysis for a smaller set of interesting markers. 相似文献
153.
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156.
Sobieralska Małgorzata Kurek Marcin Andrzej 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(3):334-341
Plant Foods for Human Nutrition - The aim of the study was to investigate the potential of using β-glucan as wall material to microencapsulate the elderberry extract. Firstly, the extract was... 相似文献
157.
Sliwa E Adaszek Ł Tatara M Dobrowolski P 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(9-10):397-405
The aim of this study was to investigate short-term 4 and 14 weeks after fundectomy) and long-term (at the age of 8 months) postoperative effects of 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate on selected serum biochemical markers in fundectomized pigs. Experimental fundectomy was performed in 30 castrated male pigs of the Pu?awska breed who received placebo or 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate up to the age of 8 months. Plasma amino acid concentrations and selected blood parameters were analyzed. Main vital organs were weighed. Our study showed that the supplementations with alpha-ketoglutarate and/or 3-hydroxy-3-methylbutyrate to fundectomized pigs significantly prevented the reduction of stomach, liver and spleen weights. However, results of this study, either positive or negative, cannot categorically establish a beneficial effect of AKG and HMB nutritional support after fundectomy in pigs. 相似文献
158.
Mukund D. Patil Bhabani S. Das Eran Barak Pratap B. S. Bhadoria Amir Polak 《Paddy and Water Environment》2010,8(2):189-198
Polymer-coated urea (PCU) is an important alternative to uncoated urea for improving nitrogen (N) use efficiency (NUE). Only
a few studies discuss their utility for lowland rice systems. A 2-year field study was conducted to examine if nitrogen loading
is reduced in lowland rice ecosystem by using mixture of PCU and uncoated urea without sacrificing yield. Five treatments
involving two mixtures of PCU with 50 and 70% coated urea each at 70 and 50% of recommended dose (80 kg N ha−1) and one with uncoated urea at 100% recommended dose were laid out in a completely randomized design. Selected plant growth
parameters and plant available N contents (NH4–N plus NO3–N) in soil solution and ponded water were measured over a period of 65 days after transplanting. Results showed no significant
difference for vegetative and yield parameters among different treatments suggesting that treatments receiving lower doses
of nitrogen exhibited higher NUE. Analysis of partial factor of productivity (PFP) for N suggested that the total N dose may
be reduced by 50% using mixtures of coated and uncoated urea. Similarly, statistically similar PFP values for treatments receiving
the same amount of total N for both years and for both total N dose suggested that the proportion of coated urea may also
be reduced to as low as 50% without sacrificing yield. Correlation analysis on nitrogen contents in ponded water and soil
solutions and the analysis of water productivity and PFP showed that soil water regime could also significantly influence
the nitrogen status in soil even when PCU are applied. In turn, both the water regime and N contents in soil ultimately influences
grain yield. Although the constant release of N from coated fertilizer ensures adequate N supply for plant uptake, it may
not completely avoid N deficit condition especially during heavy rainfall. Analysis of the developed production function suggested
that 55–65% polymer coating and about 100 cm total water input may be ideal for achieving maximum yield. The production function
was developed for PCU treatments using data observed in treatments receiving 70% recommended N dose. The range of water input
in these treatments was 86.5–174.0 cm. 相似文献
159.
Robert Jankowiak Beata Strzałka Piotr Bilański Magdalena Kacprzyk Karolina Lukášová Riikka Linnakoski Sebastian Matwiejczuk Marcin Misztela Robert Rossa 《European Journal of Forest Research》2017,136(5-6):939-956
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognised as important agents of tree mortality in coniferous forests of the Western Carpathians. They, together with weevils, are consistently associated with ophiostomatoid fungi. Information regarding conifer beetle-associated fungi in the Western Carpathians remains incomplete and unreliable, particularly with respect to fir-infesting bark beetles. This study aims to clarify associations between fungi in the genera Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in Norway spruce (Picea abies), European larch (Larix decidua) and silver fir (Abies alba). Samples associated with 20 bark beetle species and weevils were collected from nine stands in Poland and the Czech Republic. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for four gene regions (ITS, LSU, ß-tubulin, TEF 1-α) and phylogenetic analyses. In total, 46 distinct taxa were identified, including 25 known and 21 currently unknown species. Several associations between fungi and subcortical insects were recorded for the first time. In addition, O. borealis and O. quercus were detected from A. alba for the first time. The composition of the fungal communities varied among the studied tree species and to a lesser degree among the beetle species. The spruce-infesting bark beetles were commonly associated with species of Leptographium s. l. and Ophiostoma s. str.; the larch-infesting bark beetles were often associated with Ophiostoma s. str. and Sporothrix, while the fir-infesting bark beetles were commonly associated with Ophiostoma s. str. and Graphilbum. The most commonly encountered fungal associates of the examined insects were (a) Grosmannia cucullata, G. piceiperda, Grosmannia sp. 1, Ophiostoma macroclavatum and O. piceae with the spruce-infesting bark beetles; (b) O. pseudocatenulatum and Sporothrix sp. 1 with the larch-infesting bark beetles; and (c) O. piceae, Ophiostoma sp. 2 and Graphilbum sp. 2 with the fir-infesting bark beetles. The differences in fungal associates among the bark beetle species occurring on P. abies, L. decidua and A. alba could be linked to the different habitats that these beetles occupy. 相似文献
160.
Polak M Gajecka M Jakimiuk E Obremski K Gajecki M Smoczyński L Luczyński M Góra M Baranowski M Zielonka L Zwierzchowski W 《Polish journal of veterinary sciences》2004,7(3):187-191
Zearalenone (ZEA) is a member of macrocyclic lactons family. It is a toxin--phytosteride produced by fungi of Fusarium ssp. genus. Zearalenone contaminates food and animal feeding stuffs and its destruction is difficult. It requires application of particular compounds that would bind zearalenone in the feed or feeding stuff or in the gastrointestinal tract and decrease its bio-accessibility. It should also fulfil all the safety requirements regarding the plant supplements and animals that are fed with this feed. The aim of the study was to estimate if the feed supplemented with different doses of zearalenone and zearalenone destructor causes changes of the metabolic profile in gilts. The results obtained show that applied destructor did not cause negative haematological and biochemical changes in the blood of the gilts examined. It can be suggested that it is a safe feed supplement pigs in prevention of zearalenone micotoxicosis. 相似文献