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701.
Lenka Ehrenbergerová Aleš Kučera Emil Cienciala Jan Trochta Daniel Volařík 《Agroforestry Systems》2018,92(6):1551-1565
Coffee leaf rust (CLR), caused by Hemileia vastarix, is one of the most serious diseases of coffee plantations and cause great losses in coffee production. We aimed to examine coffee varieties, shade, age of coffee plants, coffee plant density and soil properties in relation to CLR infection. To do this, we established a total of 75 plots in three agroforestry coffee plantations in the central Peruvian Amazon. We gathered data there in 2011 (dry season) on the presence/absence of CLR; coffee variety; age and density of coffee plants, and also took hemispherical photographs to determine canopy openness. In 2014 (wet season), we again gathered data on the same variables. In 2012, we collected soil samples from a subset of the plots. At all plantations, coffee variety had a significant effect on CLR incidence, with the Catimor variety infected less frequently than Caturra. Coffee plant age had a significant positive effect on CLR incidence. Increasing coffee density also increased CLR incidence for some of the studied plantations/seasons. Comparing those plots from which data were collected in the dry and wet seasons, we found that CLR presence was significantly higher in the wet season. The effect of shade on CLR incidence was not clear. Catimor and Caturra varieties showed opposite trends of CLR incidence in response to shade quantity in most cases (Caturra variety CLR incidence was decreasing with shading increase and Catimor CLR incidence decreasing with decreasing shading). Finally, the soil properties did not affect CLR incidence. 相似文献
702.
Key message
Liming, an ameliorative method for acidified forest soils, affected the relative abundance of prey of ground-hunting spiders and consequently reduced densities of functionally similar species of these predators.Context
Liming, an ameliorative method for acidified forest soils, may modify the structure of an arthropod community by altering the soil characteristics and/or the availability of food resources.Aims
We investigated the effect of liming on the community structure of ground-hunting spiders in a birch forest.Methods
We established six experimental birch stand plots. Each stand was exposed to one of three experimental treatments: control, 1.5 t/ha, or 3 t/ha of dolomitic limestone. We collected spiders using pitfall traps during 5 years. We characterized the community in terms of activity density, species richness, community-weighted mean body size, and functional diversity and evenness in body size. We further investigated the potential links through which the liming might affect spiders, namely soil characteristics, effect of liming on birch, and densities of potential prey.Results
The commonly used dosage of 3 t/ha reduced densities of functionally similar species which led to the reduced functional evenness in body size and increased functional divergence in body size. Liming increased soil pH only slightly but decreased the densities of spiders’ preferred prey.Conclusion
The liming affected the community of ground-hunting spiders, at least partially, through reduced densities of their preferred prey.703.
Dušan Nikolić Ana Vučurović Ivana Stanković Nikola Radović Katarina Zečević Aleksandra Bulajić Branka Krstić 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(1):225-235
In a two-year survey (2011–2012), 3220 samples were collected and analyzed in order to determine the presence and distribution of viruses in tomato crops at 56 localities of 18 districts in Serbia. Out of 12 viruses tested, Cucumber mosaic virus (CMV), Potato virus Y (PVY), Alfalfa mosaic virus (AMV), Tomato spotted wilt virus (TSWV), Tomato mosaic virus (ToMV) and Tobacco mosaic virus (TMV) were detected in 42.1, 40, 11, 8.6, 2.3 and 1.3% of the total tested samples, respectively. The results revealed that CMV was prevalent in 2011 and PVY in 2012. CMV and PVY, apart from being predominant, were also the most widespread viruses. In general, single infections were the most frequent type of infection. Additionally, the most common mixed infections were double infections and the most prevalent combination was CMV and PVY. In 2011, the incidence of diseases and the percentage of all infection types were significantly higher than in 2012. Furthermore, in 2011, regardless of total single infections being prevalent compared to mixed infections, two prevailing viruses were commonly detected in mixed infections. The additional molecular testing of ELISA-negative samples using virus specific primers did not reveal the presence of Pepino mosaic virus (PepMV), Tomato yellow leaf curl virus (TYLC), Tomato infections chlorosis virus (TICV) and Tomato chlorosis virus (ToCV). 相似文献
704.
Effects of 5 years of digestate application on biomass production and quality of cocksfoot (Dactylis glomerata L.)
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Anaerobic digestion of biomass produces biogas for combustion and also provides a residual digestate. Although sometimes regarded as a waste product, the nutrient‐rich chemical composition of digestate makes it a potential organic fertilizer for agriculture. The goal of this study was to evaluate the effectiveness of digestate as a fertilizer on the biomass yield and chemical composition of cocksfoot (Dactylis glomerata L.). In a 5‐year small‐plot field experiment digestate fertilization treatments supplying 90, 180, 270, 360 and 450 kg N ha?1 were compared with untreated plots and plots fertilized with 180 kg N ha?1 of mineral N fertilizer. Swards fertilized with digestate produced higher biomass yield compared with the control. The same rate of nitrogen fertilizer (180 kg N ha?1) supplied as digestate and from mineral fertilizers gave similar results on biomass yield. Herbage in swards fertilized with digestate contained less nitrogen, but the C:N ratio was much more suitable for biogas production. Digestate fertilization resulted in higher concentrations of cellulose and hemicellulose in biomass and lower contents of the inhibitors of anaerobic digestion—sulphur, calcium, magnesium and phosphorus—compared with those of swards receiving mineral fertilizers. 相似文献
705.
David Tokarski Jiří Kučerík Karsten Kalbitz Michael Scott Demyan Ines Merbach Dietmar Barkusky Joerg Ruehlmann Christian Siewert 《植物养料与土壤学杂志》2018,181(5):664-674
Sustainable soil management requires reliable and accurate monitoring of changes in soil organic matter (SOM). However, despite the development of improved analytical techniques during the last decades, there are still limits in the detection of small changes in soil organic carbon content and SOM composition. This study focused on the detection of such changes under laboratory conditions by adding different organic amendments to soils. The model experiments consisted of artificially mixing soil samples from non‐fertilized plots of three German long‐term agricultural experiments in Bad Lauchstädt (silty loam), Grossbeeren (silty sand), and Müncheberg (loamy sand) with straw, farmyard manure, sheep faeces, and charcoal in quantities from 3 to 180 t ha?1 each. In these mixtures we determined the organic carbon contents by elemental analysis and by thermal mass losses (TML) determined by thermogravimetry. The results confirmed the higher reliability of elemental analysis compared to TML for organic carbon content determination. The sensitivity of both methods was not sufficient to detect the changes in organic carbon content caused by small quantities of organic amendments (3 t ha?1 or 0.1–0.4 g C kg?1 soil). In the case of elemental analysis, the detectability of changes in carbon content increased with quantities of added amendments, but the method could not distinguish different types of organic amendments. On the contrary, the based on analysis of degradation temperatures, the TML allowed this discrimination together with their quantitative analysis. For example, added charcoal was not visible in TML from 320 to 330°C, which is used for carbon content determination. However, increasing quantities of charcoal were reflected in a higher TML around 520°C. Furthermore, differences between measured (with TML110–550) and predicted mass loss on ignition using both organic carbon (with TML330) and clay contents (with TML140) were confirmed as a suitable indicator for detection of organic amendments in different types of soils. We conclude that thermogravimetry enables the sensitive detection of organic fertilizers and organic amendments in soils under arable land use. 相似文献
706.
Klopčič Matija Mina Marco Bugmann Harald Bončina Andrej 《European Journal of Forest Research》2017,136(5-6):1071-1090
European Journal of Forest Research - In the Dinaric Mountains, the future of silver fir and Norway spruce appears to be uncertain, especially given the threat of climate change to both species and... 相似文献
707.
Branimir Urlić Gvozden Dumičić Marija Romić Smiljana Goreta Ban 《Journal of plant nutrition》2017,40(18):2611-2618
Hydroponic production of rocket as a salad vegetable has become increasingly important in recent years. Rocket is known to be a high nitrate (NO3–)-accumulating vegetable, which can be grown throughout the year. In the present study, rocket was grown in a floating hydroponic system at three levels of nitrogen (N) and sodium chloride (NaCl). The highest yield was obtained at 14 mM N, whereas the yield was lower at 20 mM and 40 Mm NaCl. Leaf elongation was more sensitive to salinity than leaf differentiation. Adding NaCl to the nutrient solution increased the relative chlorophyll content. Na+ and Cl– concentrations increased as salinity increased. NO3? levels in fresh biomass increased with increased amounts of NO3? in the nutrient solution, and plants at 18 mM N were able to maintain a higher NO3? : Cl? ratio than those at 10 mM N. 相似文献
708.
L. Plošek T. Lošák S. Kužel A. Kintl D. Juřička 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(7):607-614
This paper deals with the problem of mineral N leaching from arable lands due to the fertilization method. The influence of different doses of compost (50 and 100?Mg ha?1) and N-mineral fertilizer (35-70-140 kg N ha?1) on leaching of Nmin in a lysimetric experiment with winter wheat. The area of our interest represents the main source of drinking water for the city of Brno and its neighborhoods. To demonstrate the effect of compost and mineral nitrogen addition, the lysimetric experiment was established there. Seven variants of the experiment with different fertilization schemes were studied during two vegetation seasons (2013 and 2014), each with three repetitions. The experiment was carried out in plastic experimental containers of 0.3 m diameter and 0.5 m height. Therefore, each lysimeter was the same size and was filled with 25 kg of subsoil and 25 kg of topsoil. The highest leaching of Nmin was detected in the variant C2 where 140 kg N ha?1 was applied, in both vegetation periods (5.97 kg Nmin ha?1 after the first vegetation period and 17.02 kg Nmin ha?1 after the second vegetation period). The positive effect of compost application (individually or in combination with the mineral N) on decrease in mineral N leaching was found during both vegetation period in comparison with variant C2. The highest doses of compost (100?Mg per ha) significantly decreased the concentration of mineral nitrogen in the soil eluate in both periods (3.03 kg Nmin ha?1 and 5.79 kg Nmin ha?1, respectively), by 197% and 293% in comparison with variant C2. There is evidence that the application of compost has a positive effect on the reduction of Nmin leaching. 相似文献
709.
Mato Drenjančević Vladimir Jukić Krunoslav Zmaić Toni Kujundžić 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):705-711
The aim of this study was to determine the impact of two different treatments of early defoliation performed before blooming on: grape yield, chemical parameters, polyphenols content, and antioxidant activity of grape and red wine cv. Cabernet Sauvignon from the vineyard located in Ilok, the eastern continental region of Croatia. Two different treatments of leaf removal (LR) were performed: removal of 3 leafs (T1) and 6 leafs (T2) before blooming, together with control (no leaf removal) (T3) during two years (2013 and 2014). Crop yield and average cluster weights per vine were determined. Density, pH and titratable acidity were measured in must, while the total phenols, total anthocyanins and antioxidant activity were measured in the extract of grape skin and produced wine. The analysis of individual anthocyanins in wine was performed by HPLC method. T2 treatment significantly lowered the crop yield and the average cluster weights, and increased total phenols, total anthocyanins, antioxidant activity and most abundant individual anthocyanins in wine. Defoliation did not affect the other chemical parameters in must, grape skin extract and wine. Vintage year is statistically the most significant source of variability for density of must, antioxidant activity in grape skin extract, as well as pH and titratable acidity in wine. This study has showed that the early leaf removal treatment in eastern continental part of Croatia could be used for the production of smaller quantity of high quality Cabernet Sauvignon red wine abundant with anthocyanins. 相似文献
710.
Muhammad Ayaz Urte Stulpinaite Dalia Feiziene Vita Tilvikiene Kashif Akthar Edita Baltrėnaitė-Gedienė Nerijus Striugas Urooj Rehmani Sahib Alam Rashid Iqbal Monika Toleikiene Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321
Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha−1) with N fertilizer (180 kg ha−1) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg2+ by 11%, P by 4%, K+ by 50%, and Ca2+ by 56% in the soil, and Mg2+ by 13%, P by 69%, K+ by 29, and Ca2+ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12th to 62nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development. 相似文献