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As far as honey is concerned, microwave oven heating finds its use especially for crystallised honey reliquefying. We focused on monitoring the changes in hydroxymethylfurfural content which is an indicator of heat damage done to honey, among others. Microwave honey heating was carried out in four degrees of microwave power levels over seven variously long time periods. In total, 22 analysed honey samples came directly from bee-keepers from the Czech Republic from the 2004 and 2006 harvests. Hydroxymethylfurfural content was determined by HPLC method using a liquid chromatograph Alliance 2695 with a PDA detector 2996. We obtained relatively interesting results: despite the honey having reached relatively high temperature levels (80-90°C) at the highest power levels and the longest time periods, there was no gradual significant increase in hydroxymethylfurfural content which could be expected at conventional heating. On the other hand, hydroxymethylfurfural content varied in the course of heating of the individual samples, which is a very interesting result. A significant role was played also by the botanic origin of the honeys because the course of the changes in hydroxymethylfurfural content due to microwave heating was not the same in all honeys analysed.

Little is known about the effects of air-drying and freezing on the transformation of phosphorus (P) fractions in soils. It is important that the way in which soils respond to such perturbations is better understood as there are implications for both P availability and loss to surface waters from soils. In this study, the effects of air-drying and freezing were investigated using two soils, one being a forest soil (FS) high in organic matter and the other being a sterile soil (SS) low in organic matter. Soil P was fractionated using a modified Hedley fractionation method to examine the changes of phosphorus fractions induced by air-drying and freezing. Generally, there were no significant differences of total phosphorus among the three treatments (CV% < 10%). Compared with field moist soils, freezing the soil evoked few changes on phosphorus fractions except that the resin-P increased in FS soil. On the contrary, air-drying significantly changed the distribution of phosphors fractions for both soils: increased the labile-P (especially resin-P) and organic-P (NaHCO₃-Po, NaOH-Po and Con.HCl-Po) at the expense of NaOH-Pi and occlude-P (Dil.HCl-P and Con.HCl-Pi). Resin-P significantly increased by 31% for SS soil and by 121% for FS soil upon air-drying. The effect of air-drying seemed to be more pronounced in the FS soil with high organic matter content. These results indicated that drying seem to drive the P transformation form occlude-P to labile-P and organic-P and accelerated the weathering of stable P pool. This potentially could be significant for soil P supply to plants and P losses from soils to surface waters under changing patterns of rainfall and temperature as predicted by some climate change scenarios.

Reptiles have recently become a popular group of pet animals. A relatively large number of studies on the morphology of the oral cavity and method of feeding in adult individuals have been published. Nevertheless, embryological descriptions of reptile body parts or structures are rare. In this study, we describe the morphology of the developing tongue, in particular its dorsal surface, in pre-hatched green iguanas. Microscopic examination of the oral cavity of early embryos revealed that the tongue was divided into three different areas: apex, corpus and radix. The dorsal lingual surface was smooth and covered by nonkeratinised stratified squamous epithelium with slight prominences in some cases. In the underlying mesenchyme of the tongue, striated muscular tissue was formed. The epithelium thickness was reduced during formation of the lingual papillae and in later stages remained simple cuboidal. No developing taste buds could be recognised in the lingual epithelium.

Sorghum anthracnose is a disease of worldwide importance and host-plant resistance is the most practical method of disease management. In this study, 154 sorghum accessions from the Botswana collection maintained by the United States National Plant Germplasm System were inoculated with Colletotrichum sublineolum and evaluated for disease resistance at the Tropical Agriculture Research Station in Isabela, Puerto Rico during 2007 and 2008. A resistant response was observed for 69 accessions in 2007 and for 48 accessions in 2008 with no acervuli development observed on inoculated leaves. The low frequency of resistant germplasm is expected from a region of low annual rainfall. However, disease severity was low for the susceptible accessions with a mean severity of 11% for the 85 susceptible accessions observed in 2007 and 17% for the 106 susceptible accessions identified in 2008. The highest frequency of resistant accessions was observed for the Ngamiland district with 58% of the accessions rated as resistant, whereas the frequency of resistant accessions ranged from 22% to 36% for the other districts. The lowest mean disease severity was also observed for the susceptible accessions from the Ngamiland district with the highest mean disease severity observed for susceptible accessions from the Kgatleng district. The resistant accessions identified in this study would be useful for the development of disease resistant varieties and the results indicated an ecogeographic association with disease resistance.

This study investigated copper (Cu) and lead (Pb) enrichment factor (EF) and mobility factor (MF) as possible indicators of their uptake by spinach (Spinaceae oleraceae) and carrots (Daucus carota) grown on a sludge-amended luvisol (SAL). Sewage sludge was applied to luvisol at different rates and spinach and carrots planted. Enrichment of Cu and Pb in SAL was determined, and values regressed with those of Cu and Pb concentrations in spinach and carrots. Concentration of Cu and Pb in vegetables was calculated using the regression model obtained, and calculated values compared with actual values. Pb MF were higher than Cu MF but Cu and Pb EFsoil values were < 3.0, indicating minor enrichment from sludge addition. EF had 10% reliability in predicting Cu and Pb uptake in vegetables. MF was more than 70% reliable in predicting carrot Cu uptake and spinach Pb uptake. EF and MF are not effective as predictors of heavy metal uptake by vegetables. The role of other soil components including root exudates and by-products from microbial activities should also be investigated.

Hop purchasers impose still higher requirements on the quality of the final product, which is why hop granules have to be divested of all possible impurities. One of the places that are most at risk from the given point of view is the making of hop strings and the way they are attached to the hop-field supporting structure. Commonly used hop string attachments very often remain on the supporting structure after the harvest, spontaneously loosen in the following years, penetrate into the post-harvest processing stage of the technological procedure and negatively influence the output quality of the hops. The article summarizes the results of field experiments done during the pull-down of hop vines using a common hop string, but with various attachments with the aim of looking for the most suitable treatment which would exclude the risk of impurities penetrating from this stage of the technological procedure into the final product. The measurement carried out shows that so far the most advantageous treatment is hop string with simple attachment formed by twine 12 500. Breakage of hop strings occurred in 93% in twine, while with the rest of the vines only in wire.

The purpose of this study was to analyse the microbial diversity in the caecum of geese using a 16S ribosomal RNA gene (rRNA) clone library approach. A total of 160 clones and 124 clones were sequenced and phylogenetically analysed from the contents and mucosa of the caecum of Yang Zhou geese, respectively. The result indicated that there was a rich variety of bacteria in the caecum contents. Forty-six operational taxonomic units (OTUs) based on a 98% similarity criterion were classified in the contents of goose caecum, as compared to 29 OTUs based on a 97% similarity criterion in the mucosa of goose caecum. The sequences were assigned to 7 and 5 groups in the contents and mucosa of goose caecum, respectively. Contents of goose caecum were dominantly occupied by Clostridia-related species (58.7%) with other abundant sequences being related to Bacteroidetes (26.9%) and Erysipelotrichi (11.2%). Gammaproteobacteria (59.6%) and Clostridia (20.1%) were predominant in the mucosa of goose caecum.

This case study describes the pregnancy of a German Shepherd bitch with a singleton (one puppy) litter as a result of early embryo resorption. Resorption was confirmed by ultrasonography and the pregnancy was regularly monitored by USG and measurements of progesterone levels until parturition. These levels stayed within the physiological range. One healthy puppy was delivered within the timeframe of a physiological pregnancy although the inner chorionic cavity diameter (ICCD) protocol used for predicting the time of parturition showed divergence from the real time of whelping.

We studied the effectivity of a commercial antibiotic kit Mycokill AB for the elimination of mycoplasma contamination in virus strains. The contaminated virus strains were first filtered, treated with Mycokill AB for three hours and repeatedly passaged in its presence in the cultivation medium in pure cell lines. Three passages in the presence of Mycokill AB were invariably followed by three passages without Mycokill AB. The effectivity of purification was then checked by PCR. Twenty-four out of 28 tested virus strains became free of mycoplasma after a first or second cycle of the treatment with Mycokill AB. The other four strains remained positive even after repeated passages. In these cases of a likely resistance to Mycokill AB, we managed to eliminate the mycoplasma contamination through a subsequent treatment with the antibiotic combination BM-Cyclin. Mycokill AB was shown in the elimination of mycoplasma from virus suspensions as successful as other known most effective antibiotics.

In conifers and other plants with long reproductive cycles, transformed embryogenic tissues can serve as a convenient source of plant material for the testing of insecticidal or fungicidal transgene efficiency. In this report, transgenic embryogenic tissue was obtained after the transformation of somatic embryos of Norway spruce (Picea abies (L.) Karst.) by Agrobacterium tumefaciens with the gus-intron chimeric gene. The stable integration of transgenes was confirmed by PCR and Southern hybridization. The transformation was successful only in a suitable embryogenic cell line sensitive to Agrobacterium. Out of the nine embryogenic lines tested only one gave transgenic callus.

Virulences to powdery mildew resistances in barley cultivars mostly carrying unknown resistances were determined in 2009 and 2010. Random spore samples of the airborne pathogen populations originating from winter and spring barley fields were obtained by means of a mobile version of a jet spore sampler by travelling across theCzech Republic. In total 301 isolates were studied, 55 differentials carrying mostly unknown resistances were used and 80 pathotypes were found, of which 26 representing 73.1% of isolates were detected in both years. Virulence frequencies showed a wide range from 0% to 100%. Complexity of the 2010 population slightly increased, mostly due to increasing frequencies of virulence to new resistances, whereas the complexity of virulences to resistances in most other differentials decreased. Pathotype 00027 was the most abundant (10.0%). Diversity of the 2010 population considerably increased due to changes in virulence frequencies.

The resistance Heils Hanna (HH) was postulated in several tens of 471 previously tested winter barley cultivars. In this paper, new tests on 29 of these cultivars are reported. Thirty-two reference isolates of Blumeria graminis f.sp. hordei held in the pathogen genebank at the Agricultural Research Institute in Kromeriz, Ltd. including a Japanese isolate and five Israeli isolates were used for response tests. However, the resistance HH conferred by the gene Mla8 and herein characterised by reaction type 0 to an old Japanese isolate known as Race I was now postulated only in four cultivars. In the other 25 cultivars another resistance, characterised by reaction type 0 to Race I and also to two Israeli isolates, was detected. In addition to the two mentioned resistances, eight known (Bw, Dr2, Ha, IM9, Ln, Lv, Ra and Sp) resistances were found in the set examined. Lomerit was the only registered cultivar tested here in which the newly detected resistance was present alone, therefore, it is recommended that this resistance be designated Lo.

In five consecutive growth seasons from 2003 to 2007 a response of maize variety Eurostar (var. FAO 240) to supply of NPK fertilizer supplemented with magnesium or zinc was investigated. The aim of the study was to evaluate the role of zinc (NPK + Zn) or magnesium (NPK + Mg) in controlling nitrogen management by maize crop fertilized with 80 and 140 kg N/ha. In the course of the study, total grain nitrogen content did not show any response to both experimental factors and weather variability, as well. However, the obtained results indicate, that magnesium and zinc have significantly increased SPAD (chlorophyll index) indices of maize cob leaf at anthesis. A significant effect of both factors interaction on nitrogen accumulation in grain and cob covering leaves was noted, but limited to the 80 kg N/ha treatment. The physiological role of Mg and Zn in nitrogen management was most manifested throughout its greater recovery from nitrogen fertilizer applied at the rate 80 kg N/ha, amounting to 92 and 94% respectively; for the NPK, it was only 78%.

The objective of this study was to compare the metabolic and electrolytic profile as well as the morphological appearance of the umbilical cord and newly born piglets' weight that failed the vitality test scale compared to those who passed. Newborn piglets were divided into three groups according to the vitality with a modified Apgar score at birth: Group 1, failing with a score < 5 (G₁: n = 218), Group 2 had a score of 6 to 7 (G₂: n = 439) and Group 3 had scores > 8 (G₃: n = 464). Results showed significant differences among groups (P < 0.05) in the physio-metabolic pH, PCO₂, PO₂, Na⁺, Ca²⁺, glucose, lactate and bicarbonate values. Regarding weight, temperature and latency to connect the maternal teat, there were also significant differences (P < 0.05) among groups; it took 23.38 min for G₃ while neonatal piglets from G₁ took 30 min longer (P < 0.05) to make the first teat contact. The neonates from the latter group had a higher percentage (75.68%) of broken umbilical cords, with higher birth weight (+200 g, P < 0.05), showed higher than normal blood glucose concentrations, and had lower body temperature at birth (-0.7°C, P < 0.05) and PO₂ in comparison with the other groups of neonates that passed the vitality score. A novel point of this study is the profile characterization of piglets that failed and passed the vitality score; we expect that the data provided may be applicable as reference values of metabolic and electrolyte blood profiles in newborn piglets according to their vitality. In conclusion, this study demonstrates that low vitality newborn piglets had clearly undergone through perinatal asphyxia. Potential indicators increasing this condition are: high birth weight, low body temperature, vitality score ≤ 5, and the presence of the broken umbilical cord at birth.

We describe the case of a nine-day-old female Holstein calf which had cheiloschisis, a moderate dome-shaped head, ataxia and opisthotonus since birth. No significant findings except the dome-shaped head were observed on survey radiography of the skull. Computed tomography (CT) images showed bilateral lateral ventriculomegaly, cerebellar hypoplasia and a cyst-like lesion communicating with the right lateral ventricle. Post-mortem examination revealed a cerebral defect in the frontoparietal lobe, which communicated with the right lateral ventricle, and cerebellar hypoplasia. CT provided a characteristic finding of porencephaly and was helpful for diagnosing the accompanying anomalies. We suggest that porencephaly should be included as a specific anomaly in the differential diagnosis of congenital brain malformation.

Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkonoše and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkonoše Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkonoše Mts. implies that the macromycete species composition developed quite differently but with a similar success.

This paper analyses the development of agricultural foreign trade in Austria, Hungary and the Czech Republic with the aim of uncovering the changes that have impacted the Central European agricultural trade over the ten year period (1999-2008). It issues from the results of the analysis of agricultural trade in the aforementioned countries, which has changed dramatically in terms of the commodity structure, the territorial structure and primarily the value structure. The main changes to have caused most of the changes to the individual characteristics of agricultural foreign trade in the particular countries under analysis are the process of the EU enlargementy, the adoption of obligations to ensue from the EU membership and the concentration in the internal market of the EU countries. We can see the actual changes in the commodity and territorial structure of the trade carried out in the individual countries under analysis. The changes which have occurred resulted in a dominant share of the member countries of the EU 27 in the agricultural trade of the individual countries under analysis.

This article examines the factor content of agricultural trade in the Central and East European (CEE) transition countries. It relates the factor content of agricultural trade to the cross-country differences in technology stemming from different farm organisations between the CEE countries agricultural sectors and to the differences in relative factor endowments. The relative factor endowments alone do not satisfactorily explain agricultural trade flows in the CEE countries. We find that transaction costs and market imperfections that affect the organisation of production also distort farm specialisation and hence V the actor content of agricultural trade.

A total of 30 tea samples of different origins, thirteen green tea samples, thirteen black tea samples, two semi-fermented tea samples and one white tea, imported to the Czech Republic, were collected and analysed for the total content of copper, iron, manganese, and zinc in tea leaves and tea infusions. The total contents of metals in tea leaves differ according to the type of tea (green or black) and are probably influenced by many other factors, e.g. soil properties. The total contents of Mn were much higher compared to the total contents of Cu, Fe, and Zn, and varied between 511-2220 mg/kg. To compare easily hot water soluble concentrations of Cu, Fe, Mn and Zn, 5 min, 60 min, and 24 h infusions were prepared. The extractability of the elements was in the order Cu > Zn > Mn > Fe. The proportions of the element contents in the infusion related to the respective total contents in leaves were 30 ± 16% Cu, 26 ± 10% Zn, 18 ± 10% Mn, and 1.5 ± 0.8% Fe, respectively. The results confirmed that tea infusion can be an important dietary source of Mn.

Soil tillage practices involving various depth, intensity, and different methods of loosening the soil and treating plant residues have changed significantly in recent years and have spread also due to technical advance. The reasons are not only in expected benefits for crop production economics but also in preserving and increasing soil fertility. Although the practices were known for decades, their greatest development and use was seen only in the last 15 years, when decreasing production costs, efficient technology and effective herbicides were the main reasons for their development. At present, they are regarded as important alternatives to conventional management practices with moldboard plowing. Minimum soil tillage practices can contribute to effective soil management, however, risks associated with using these practices in various farming conditions shall be regarded. For cereals, these risks also include disease severity that is conditioned by several circumstances, which change along with the crop management practice, variety assortment or weather in individual years. Diseases that can be of greater importance in relation to the conservation soil tillage practice are stem-base diseases, root diseases and Fusarium head blight. Our experiments did not demonstrate an increased demand for protection against Fusarium head blight, foot diseases and take-all in the given system (three-crop rotation where wheat followed white mustard). Individual years were an important factor.

This study had the aim of investigating the anatomy of the aortic arch in squirrels (Sciurus vulgaris). Ten squirrels were studied. The materials were carefully dissected and the arterial patterns of arteries originating from the aortic arch were examined. The brachiocephalic trunk and the left subclavian artery were detached from the aortic arch. The brachiocephalic trunk first gave the left common carotid artery, and then detached to the right subclavian and common carotid artery. In all the examined materials, the left and right subclavian arteries gave branches that were similar after leaving the thoracic cavity from the cranial thoracic entrance. But while the whole branches of the the right subclavian artery were arising from almost the same point the left subclavian artery gave these branches in a definite order, and the branches that separated were the following: the internal thoracic artery, the intercostal suprema artery, the ramus spinalis, the vertebral artery and the descending scapular artery. It also gave the common branch formed by the junction of three of the cervical superficial, the cevical profund and the suprascapular arteries. After the separation of these branches, continuation of the artery gave the external thoracic artery on the external face of the thoracic cavity and then formed the axillar artery. The axillary artery separated into the subscapular and the brachial arteries. Thus, the arteries originating from the aortic arch and the branches of these arteries are different from other rodents and from domestic mammals.

This article describes osteomyelitis of the sphenoid skull bone in a maltanese dog due to Cryptococcus neoformans var. neoformans infection. The affected dog was subjected to physical and neurological examinations. Complete blood count (CBC), biochemistry profile, lymph node biopsy, cerebrospinal fluid (CSF) examination were also performed. This case report describes abnormalities in magnetic resonance imaging (MRI) examination as well as the histhopathologic lesions of the skull bones and neurological symptoms of the dog.

The paper analyzes the main indicators of the economic position of companies in the field of food industry in Vojvodina. The examined nine-year period coincides with the final stage of the ownership transformation in the Republic of Serbia. Given the length of the examined period, a considerable devaluation of the national currency (60.6%) and a high inflation rate (125.7%), all values are shown in Euros. The increasing business activity in the period of interest is not accompanied by the appropriate financial effects. Food industry enterprises achieved a positive financial result for most of the years in the given period, but with modest profit rates (0.15-3.18%). Net working capital covers only 42.5% in average of the base stock, indicating an unfavourable financial structure and serious liquidity problems. An unacceptably high level of indebtness has been achieved (58.1%), which significantly reduces financial results due to the high financing expense. A further increase of export, combined with the recapitalization by the owners and a partial refinancing of credits, is the way to the companies' financial recovery.

Bread-making quality of wheat flour is influenced by wheat storage proteins. The percentage of sodium dodecyl sulphate (SDS)-unextracted polymeric proteins in total polymeric proteins (% UPP), as one important factors determining bread-making quality, is largely influenced by the individual and interactive effect of genetical background and environmental conditions. Four spring wheat cultivars were grown in green house. Two of the cultivars have high molecular weight glutenin subunits 5+10 while the other two have 2+12. Four different nitrogen regimes and two different temperature levels (distinguished as low and high temperature) were used. The results highlighted the importance of interactive influence of cultivars, nitrogen regimes and temperature levels for creating differences in the amount of % UPP during grain maturation period (GMP) and at maturity. The shift to end up with either high or low % UPP at maturity happened early during GMP (around 12 days after anthesis). Influences of cultivars on % UPP was found early during the GMP while influences of temperature and nitrogen regimes were seen much later during the GMP. The results will help in understanding the relationship between quality parameters of wheat flour and how these are influenced by different environmental and genetic factors.

The present investigation was undertaken to find out efficient strains of arbuscular mycorrhiza (AM fungi) alone or in combinations with Trichoderma viride for inoculation Dendrocalamus strictus L. seedlings. The inoculated seedlings showed good response having higher plant height, phosphorous ions content in root and shoot, AM spore number and root colonization than non-inoculated (control) seedlings in both single (alone) and co-inoculation (combined consortium) experiments. T. viride showed significant growth followed by Glomus mosseae, G. fasciculatum and mixed AM with single inoculation. In co-inoculation, the best growth responses were observed with G. fasciculatum + T. viride followed by G. mosseae + T. viride, mixed vesicular arbuscular mycorrhizas (VAM) + T. viride, G. mosseae + G. fasciculatum + T. viride + mixed VAM, G. mosseae + G. fasciculatum + T. viride and G. mosseae + G. fasciculatum after 120 days and also depicted maximum increase in phosphorus content of shoot and root when compared with other inoculated seedlings. However, all the inoculated seedlings showed significant increase in phosphorus content when compared with control seedlings.

The effects of temperature pre-treatment, thidiazuron, naphthaleneacetic acid, and 6-benzylaminopurine on in vitro gynogenic plant production from un-pollinated melon (Cucumis melo L.) ovaries were investigated. Simple sequence repeat (SSR) marker analysis was conducted to identify the homozygous diploid individuals. The temperature pre-treatment (4°C) for 4 days increased embryo formation frequency (63.3%) significantly. Addition of thidiazuron (0.04 and 0.02 mg/l) in the induction medium significantly increased the number of responding ovaries (46.6%, 65.83%), respectively. The maximum number of plantlet regeneration (22.5%) was achieved by culturing the ovary derived embryos on Murashigue and Skoog medium (MS medium) supplement with 0.6 mg/l 6-benzylaminopurine. Spontaneous doubled haploids originated directly through embryogenesis were subjected to genetic analysis using SSR molecular marker with 23 primers pair for homozygosity. SSR markers with microsatellite CMGA172, confirmed that the alleles in the parental material were also present in the gynogenic plantlets, but amplified only two alleles as compared to four alleles of the heterozygous parent material at same locus. Therefore these regenerated plantlets were consider homozygous and produced through a process of gametophytic embryogenesis.

Our study aimed to determine morphometric data for wild boar (Sus scrofa) in various areas of the Czech Republic and the potential influence of environment on its body measurements. Three localities with varying agricultural systems and overall landscape structure were selected. Hunted boars were measured for height at the withers, body length, ear length, metatarsal length and weight (depending on the circumstances, either dressed with head, without head, or undressed). We also determined the age of the hunted boars according to teeth development. During 2003-2007, a total 654 boars were examined in various age categories. Body development was similar in all areas and without statistically significant differences until the age of 6-7 months. From 8 months, statistically significant differences in body proportions occur across all localities. It is just at that time that carrying capacities change in the selected localities. The results show that morphometric differences among boars of the same age are influenced by external environmental conditions in which the boars live.

Overgrazing affects typical steppe community in ways similar to grasslands in other areas. Exclusion of livestock grazing is one of the main management practices used to protect grasslands. However, it is not known if long-term exclusion of livestock grazing has positive effect on above- and belowground community properties in typical steppe of the Loess Plateau. We studied the long-term (20-year) cumulative effects of exclusion of livestock grazing on above- and belowground community properties compared with that before exclusion of livestock grazing in a typical steppe of the Loess Plateau, NW China. Our results show that twenty-year exclusion of livestock grazing significantly increased above- and belowground biomass, species richness, cover and height for five different communities. Most of belowground biomass was in the 0-20 cm horizon and grazing exclusion increased biomass especially at the depth of 0-10 cm. Our study suggests that long-term exclusion of livestock grazing can greatly improve community properties of typical steppe in the Loess Plateau.

Organic manure is considered as a beneficial fertilizer on soil quality and an excellent alternative resource of chemical fertilizer (CF). However, organic manure from intensive farms may have a negative impact on soil quality because of containing some harmful components, such as heavy metal and antibiotics. The aim of this study was to determine the influence of poultry litter (PL) and livestock manure (LM) from intensive farming on soil physical and biological indicators of soil quality. Results showed that PL and LM amendment increased soil macropore and mesopore volumes and decreased soil micropore volumes. Tensile strength in PL and LM treatment were lower than those in CF, while soil aggregate wet stability index were greater than those in CF. Compared with CF treatment, the microbial biomass C and N contents (+89%, +74%), soil basal respiration rate (+49%) and soil microbial quotient (+45%) in PL and LM treatment were significantly greater. Significant linear correlations were found between soil organic carbon and most soil physical and biological properties (P < 0.01). The results suggested that modern intensive farm manures can be alternate chemical fertilizers as a main fertilizer to improve soil physical and biological indicators in a rice-wheat system.