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21.
The aim of this paper was to give a basic understanding of studies on methane emissions of New Zealand, as we know the agriculture of New Zealand is pastoral farming, most livestock animals are grazed in pasture, and quantities of methane were released from the digestive tract and animals excreta. In New Zealand some 50% greenhouse gases (GHG) sources are attributed to agriculture and one third is methane from livestock enteric formation. For many years, many researchers have been exploiting the techniques and methods to measure the emission of methane of New Zealand, further more studing the available options to alleviate the methane emissions. Their pioneering work and successful experiences including the determined methods and mitigation strategies are worth learning for scholars around the world. Some of their approaches were not only suitable for New Zealand grazed livestock, but for many other countries, even the animals are intensively bred in pen. The calorimeter/respiration chamber is the most exactly method in present, but it needs expensive equipments and skilled manipulators, so there are still some difficulty in applying this approach extensively in practice. Sulfur hexafluoride (SF6) trace technique is much adopted for grazed livestock evaluating the methane emission, though its veracity was doubted by some researchers, it is still a good option in present for studying the GHG emissions for grazing animals. By measuring the rumen volatile fatty acid (VFA) concentration to estimate the methane emission is a relatively simple approach, it is just only a rough evaluation, and it is unsuitable for exact study, but this method may be used in China for extensively raised ruminant. In present China, the ruminants are fed in an extensively managed state, the diversities of roughage and animals varieties caused difficult to exactly estimate the methane emission. So exploiting the available options is much important for constituting the exhaustive emission inventory. This review just maybe a good reference for researchers to carry out their studies in years and acquired great achievements in methane mitigation area. outline some practical techniques of New Zealand, those this field, after all New Zealand have been persisting many 相似文献
22.
Edyta Wojciechowska Christoph H. Weinert Björn Egert Bernhard Trierweiler Markus Schmidt-Heydt Bernd Horneburg Simone Graeff-Hönninger Sabine E. Kulling Rolf Geisen 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(4):735-747
Tomato fruits can be contaminated by saprophytic strains of Alternaria alternata which is the reason for the frequent occurrence of Alternaria toxins like alternariol, alternariol monomethylether or tenuazonic acid in these types of products. It was shown earlier that alternariol is a colonization factor for tomatoes. In the current analysis two different tomato genotypes were analysed by untargeted comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). This analysis revealed clear differences in the metabolic profiles which were paralleled by differences in resistance towards Alternaria colonization. One of the genotypes was more resistant against A. alternata infection and contained high amounts of chlorogenic acid in contrast to the other genotype which was sensitive against infection. In in vitro analysis, chlorogenic acid reduced alternariol biosynthesis during the first days of growth of A. alternata. Expression analysis of the alternariol polyketide synthase gene, a key gene in the biosynthesis of alternariol, also revealed a temporal reduction in its expression in the first phases of growth. However by chromatographic analysis it could be demonstrated that chlorogenic acid was degraded over time. This degradation leads to a relief of inhibition resulting in an only temporal inhibition of alternariol biosynthesis. In vivo colonization experiments revealed that chlorogenic acid reduces colonization of tomatoes by A. alternata in a concentration dependent manner, which however is partly counteracted by the addition of alterariol. 相似文献
23.
Chiara Nobili Simone D’Angeli Maria Maddalena Altamura Valeria Scala Anna Adele Fabbri Massimo Reverberi Corrado Fanelli 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(2):423-438
Wheat germinating caryopses may represent a starting point for the Fusarium Head Blight disease; however, only few studies concern the defence repertoire of wheat caryopses against fungal challenge. The germinating caryopses of two wheat commercial varieties (Blasco and Sagittario), differentially susceptible to FHB in the field, were inoculated with F. graminearum and the redox status in the interaction milieu, oxylipin production, the expression profile of some host-defence related genes, and programmed cell death in the aleuronic layer, were analysed. In Sagittario, the redox balance was profoundly modified and 9-oxylipins accumulated during fungal contamination. In this variety, F. graminearum produced a high quantity of deoxynivalenol whilst programmed cell death, also through metacaspases activation, was enhanced in the aleuronic layer of its caryopses. In Blasco, the expression of tolerance factors such as Pathogenesis-Related-protein1, glucosyl-transferase and glutathione transferase genes was up-regulated consequent to infection. Results show that unscavenged ROS and 9-oxylipins may be related to deoxynivalenol accumulation in the germinating caryopses of wheat after F. graminearum infection. 相似文献
24.
Virulence-associated trimeric autotransporters of Haemophilus parasuis are antigenic proteins expressed in vivo 总被引:1,自引:0,他引:1
Alex Olvera Sonia Pina Marta P��rez-Sim�� Simone Oliveira Albert Bensaid 《Veterinary research》2010,41(3)
Glässer’s disease is a re-emerging swine disease characterized by a severe septicaemia. Vaccination has been widely used to control the disease, although there is a lack of extended cross-protection. Trimeric autotransporters, a family of surface exposed proteins implicated in host-pathogen interactions, are good vaccine candidates. Members of this family have been described in Haemophilus parasuis and designated as virulence-associated trimeric autotransporters (VtaA). In this work, we produced 15 recombinant VtaA passenger domains and looked for the presence of antibodies directed against them in immune sera by immunoblotting. After infection with a subclinical dose of H. parasuis Nagasaki, an IgG mediated antibody response against 6 (VtaA1, 5, 6, 8, 9 and 10) of the 13 VtaA of the Nagasaki strain was detected, indicating that they are expressed in vivo. IgA production against VtaA was detected in only one animal. VtaA were more likely to be late antigens when compared to early (Omp P5 and Omp P6) and late (YaeT) defined antigens. Antibody cross-reaction with two orthologs of Nagasaki’s VtaA5 and 6, VtaA15 and 16 of strain HP1319, was also detected. No antibodies against VtaA were detected in the sera of animals immunized with a bacterin of the Nagasaki strain, suggesting poor expression in the in vitro conditions used. Taken together, these results indicate that VtaA are good candidate immunogens that could be used to improve H. parasuis vaccines. However, their capacity to confer protective immunity needs to be further studied. 相似文献
25.
Tree performance and fruit yield and quality of ‘Okitsu’ Satsuma mandarin grafted on 12 rootstocks 总被引:1,自引:0,他引:1
Tatiana Cantuarias-Avilés Francisco de Assis Alves Mourão Filho Eduardo Sanches Stuchi Simone Rodrigues da Silva Erick Espinoza-Núñez 《Scientia Horticulturae》2010
The citriculture in Brazil, as well as in other important regions in the world, is based on very few mandarin cultivars. This fact leads to a short harvest period and higher prices for off-season fruit. The ‘Okitsu’ Satsuma (Citrus unshiu Marc.) is among the earliest ripening mandarin cultivars, and it is considered to be tolerant to citrus canker (Xanthomonas citri subsp. citri Schaad et al.) and to citrus variegated chlorosis (Xylella fastidiosa Wells et al.). Despite having regular fruit quality under hot climate conditions, the early fruit maturation and absence of seeds of ‘Okitsu’ fruits are well suited for the local market in the summer (December through March), when the availability of citrus fruits for fresh consumption is limited. Yet, only a few studies have been conducted in Brazil on rootstocks for ‘Okitsu’. Consequently, a field trial was carried out in Bebedouro, São Paulo State, to evaluate the horticultural performance of ‘Okitsu’ Satsuma mandarin budded onto 12 rootstocks: the citrandarin ‘Changsha’ mandarin (Citrus reticulata Blanco) × Poncirus trifoliata ‘English Small’; the hybrid Rangpur lime (Citrus limonia Osbeck) × ‘Swingle’ citrumelo (P. trifoliata (L.) Raf. × Citrus paradisi Macfad.); the trifoliates (P. trifoliata (L.) Raf.) ‘Rubidoux’, ‘FCAV’ and ‘Flying Dragon’ (P. trifoliata var. monstrosa); the mandarins ‘Sun Chu Sha Kat’ (C. reticulata Blanco) and ‘Sunki’ (Citrus sunki (Hayata) Hort. ex. Tanaka); the Rangpur limes (C. limonia Osbeck) ‘Cravo Limeira’ and ‘Cravo FCAV’; ‘Carrizo’ citrange (Citrus sinensis × P. trifoliata), ‘Swingle’ citrumelo (P. trifoliata × C. paradisi), and ‘Orlando’ tangelo (C. paradisi × Citrus tangerina cv. ‘Dancy’). The experimental grove was planted in 2001, using a 6 m × 3 m spacing, in a randomized block design. No supplementary irrigation was applied. Fruit yield, canopy volume, and fruit quality were assessed for each rootstock. A cluster multivariate analysis identified three different rootstock pairs with similar effects on plant growth, yield and fruit quality of ‘Okitsu’ mandarin. The ‘Flying Dragon’ trifoliate had a unique effect over the ‘Okitsu’ trees performance, inducing lower canopy volume and higher yield efficiency and fruit quality, and might be suitable for high-density plantings. The ‘Cravo Limeira’ and ‘Cravo FCAV’ Rangpur limes induced early-ripening of fruits, with low fruit quality. ‘Sun Chu Sha Kat’ and ‘Sunki’ mandarins and the ‘Orlando’ tangelo conferred lower yield efficiency and less content of soluble solids for the latter rootstock. 相似文献
26.
27.
Jose V. Moris Giorgio Vacchiano Simone Ravetto Enri Michele Lonati Renzo Motta Davide Ascoli 《New Forests》2017,48(5):663-683
European larch is a dominant species in the subalpine belt of the western Alps. Despite recent increases in wildfire activity in this region, fire ecology of European larch is poorly understood compared to other larch species around the world. This study aims to assess whether European larch forests are resilient to fires, and to find out the factors that drive such resilience. We assessed the recovery of larch forests along a gradient of fire severity (low, moderate, high) based on the abundance and dominance of post-fire larch regeneration. We established 200 plots distributed among burned larch forests in nine wildfires that occurred between 1973 and 2007 in the western Alps. We included variables regarding topography, climate, fire severity, fire legacies, ground cover, grazing intensity, and time since fire. To evaluate potential drivers of larch recruitment, we applied generalized linear mixed models (GLMM) and random forests (RF). Larch regeneration was much more abundant and dominant in the moderate- and high-severity fire classes than in the low-severity class. More than half of the plots in the moderate- and high-severity classes were classified as resilient, i.e., post-fire larch regeneration was enough to recover a larch stand. GLMM and RF produced complementary results: fire severity and legacies, such as snags, canopy cover and distance to seed source, were crucial factors explaining post-fire larch recruitment. This study shows that fire has a positive effect on larch regeneration, and we conclude that European larch forests are highly resilient to mixed-severity fires in the western Alps. 相似文献
28.
Maike?Krauss Hans-Martin?KrauseEmail author Simone?Spangler Ellen?Kandeler Sebastian?Behrens Andreas?Kappler Paul?M?der Andreas?Gattinger 《Biology and Fertility of Soils》2017,53(1):49-59
Since the development of effective N2O mitigation options is a key challenge for future agricultural practice, we studied the interactive effect of tillage systems on fertilizer-derived N2O emissions and the abundance of microbial communities involved in N2O production and reduction. Soil samples from 0–10 cm and 10–20 cm depth of reduced tillage and ploughed plots were incubated with dairy slurry (SL) and manure compost (MC) in comparison with calcium ammonium nitrate (CAN) and an unfertilized control (ZERO) for 42 days. N2O and CO2 fluxes, ammonium, nitrate, dissolved organic C, and functional gene abundances (16S rRNA gene, nirK, nirS, nosZ, bacterial and archaeal amoA) were regularly monitored. Averaged across all soil samples, N2O emissions decreased in the order CAN and SL (CAN?=?748.8?±?206.3, SL?=?489.4?±?107.2 μg kg?1) followed by MC (284.2?±?67.3 μg kg?1) and ZERO (29.1?±?5.9 μg kg?1). Highest cumulative N2O emissions were found in 10–20 cm of the reduced tilled soil in CAN and SL. N2O fluxes were assigned to ammonium as source in CAN and SL and correlated positively to bacterial amoA abundances. Additionally, nosZ abundances correlated negatively to N2O fluxes in the organic fertilizer treatments. Soils showed a gradient in soil organic C, 16S rRNA, nirK, and nosZ with greater amounts in the 0–10 than 10–20 cm layer. Abundances of bacterial and archaeal amoA were higher in reduced tilled soil compared to ploughed soils. The study highlights that tillage system induced biophysicochemical stratification impacts net N2O emissions within the soil profile according to N and C species added during fertilization. 相似文献
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