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This review summarises information from the literature and experimental experience of the authors in research on weed resistance to herbicides. Factors conditioning the origin of resistance are described. The origin of resistant weeds to nine active ingredients with a different mode of action is presented chronologically, and the distribution of resistant weeds around the world outlined. The fundamental modes of action: reduction of the target site sensitivity, so-called "target site resistance", and the mode by which a herbicide is metabolised into inactive products, are listed. Function and genetic modifications of target sites of selected herbicides are described. Czech biotypes of resistant weeds with a mutation at codon 264 of the psbA gene encoding the D1 protein and at codon 574 of the acetolactate synthase gene are presented.

Peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), has been a serious pest in the last decade attacking a wide range of fruits in Egypt. The toxicity of Malathion, Diazinon, Methoxyfenozide, and Lufenuron to adult males and females of Bactrocera zonata was studied under laboratory conditions. Diazinon was the most toxic among the tested compounds followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata at 24 h post treatment, the respective LC₅₀ values were 0.20 ppm, 0.48ppm, 8.97ppm, and 9.73ppm for males and 0.26 ppm, 0.91ppm, 11.26ppm, and 14.12ppm for females. At 48 h post treatment Diazinon was the most toxic followed by Malathion, Methoxyfenozide and Lufenuron to Bactrocera zonata, LC₅₀ values were 0.09ppm, 0.34ppm, 1.60ppm, and 1.88 ppm for males and 0.14 ppm, 0.44ppm, 1.68ppm and 2.17 ppm for females. At 72 h post treatment Diazinon was the most toxic followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata, LC₅₀ values were 0.02 ppm, 0.13ppm, 0.22ppm and 0.51ppm for males and 0.07 ppm, 0.16ppm, 0.55 ppm and 0.62 ppm for females. It is observed that LC₅₀ values for treated adult females increased more than in the treated adult males at 24 h, 48 h, and 72 h post treatment. It means that the adult males were more susceptible to the tested insecticides than the adult females.

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.

Field experiments were conducted at the Agricultural Engineering Experimental Farm of The Federal University of Technology, Akure, during 2006/2007 and 2007/2008 seasons to investigate the response of cassava under drip irrigation. The experiment was laid out in a randomised complete block design (RCBD) with three replications. The treatments were based on four different water regimes; with T100 receiving 100% available water (AW), T₅₀ and T₂₅ receiving 50% and 25% of AW and T₀ with zero irrigation (control treatment). Disease free stems of the cassava cultivar TMS 91934 were planted at a spacing of 1 m by 1 m. The results indicated that T₁₀₀ full treatment produced the highest average total dry matter yield of 49.12 and 37.62 t/ha in 2006/07 and 2007/08 cropping seasons, respectively. However, the average total dry matter production in T₅₀, T₂₅, and T₀ showed significant differences in their values. Low total dry matter yields of 7.12 and 5.92 t/ha, respectively, were associated with T₀ for the two cropping seasons. The total water use of 1491.75 and 1701.13 mm was recorded for T₁₀₀, while total water use of 729.00 and 651.13 mm were obtained for T₀ in the two cropping seasons. The water use efficiency determined for the two cropping seasons ranged between 7.38 kg/ha and 32.93 kg/ha. The percentages of total water applied from total water use for T₁₀₀ were 51.11% and 61.72%, while 14.83% and 17.85% were recorded for T₂₅ for 2006/07 and 2007/08 cropping seasons, respectively.

This study was performed to make a surgical model of osteoarthritis (OA) in the dog. Experimental medial patellar luxation (MPL) was surgically produced in the left stifle (index) of 24 skeletally mature mixed small breed dogs (age two to six years and weight 2.8 to 9 kg). The animals were randomly allocated in 2 groups; sham group (n = 12), where the right stifle was sham operated and control group (n = 12) with intact right stifle. Physical and radiographic examinations of both stifles were performed at 1.5 months intervals over a one-year experimental period. One dog was euthanatized every three months, and both stifles were explored, gross examination was performed and tissue samples from the articular cartilage, cranial cruciate ligament (CCL) and synovium were collected for histomorphology. The clinical signs of OA were obvious in the experimental dogs by 12 weeks of surgical induction of MPL, which was also evidenced in the histopathology of the joint tissues and electron microscopy of the articular cartilage. The radiographic changes of OA were not obvious until remarkable degenerative changes became abvious six months postoperatively. Surgically induced MPL can be a successful tool for experimental induction of OA in dogs.

The aim of the paper was to evaluate the efficiency of winter rape growing which is based on the calculations and an analysis of production and economic indicators in the given branch. The development analysis of yields per hectare, costs, revenues and production profitability was carried out over the years 2003-2009 in the Agro Žlunice and it was compared with the results of the Czech Republic as a whole. In the enterprise, it deals with the traditional growing technology with a higher intensity of the intensification factors inputs in growing. Yields per hectare in the farm reached very favourable values which supported the stable position of the enterprise in the market with this agricultural commodity. It is possible to see a competitive advantage in the level of the per hectare yields. An average yield in the joint-stock company from 2003 to 2009 was 4.34 t/ha and an average yield in the CR over the last seven years was 2.9 t/ha. The enterprise's yield is by 1.44 t per ha higher compared to the average yields in the CR. In comparison of the average costs per hectare over the evaluated period in the enterprise and in the CR - in the enterprise, the costs were by 2.71% higher comapred to the CR (the enterprise 21 991 CZK/ha, the CR 21 394 CZK/ha). However, the enterprise Agro Žlunice, a.s. reached in comparison of the cost per 1 tonne of production by 31.31% lower costs than is the CR average. The amount of expenses incurred was compensated by high yields per hectare which the enterprise reached and thereby it improved the profitability of growing of this crop-plant. The highest share in the total costs belonged to direct material costs. The share of material costs in the enterprise over 7 years was 55.28%. Among the direct material costs, there are mainly seeds, fertilizers and chemical prophylactics. From the indicators of production profitability, there are expressed the profit achieved per 1 t of seedsfrom 1 ha of the area under crop and cost profitability. The profitability indicators considerably fluctuate during the evaluated years in the monitored enterprise and in the CR in dependence on the fluctuation of the seed price.

Changbai Mountain Natural Reserve (1,985 km² and 2,734 m a.s.l.) of Northeast China is a typical ecosystem representing the temperate biosphere. The vegetation is vertically divided into 4 dominant zones: broadleaved Korean pine forest (annual temperature 2.32°C, annual precipitation 703.62 mm), dark coniferous forest (annual temperature -1.78°C, annual precipitation 933.67 mm), Erman's birch forest (annual temperature -2.80°C, annual precipitation 1,002.09 mm) and Alpine tundra (annual temperature -3.82°C, annual precipitation 1,075.53 mm). Studies of soil carbon (C) and nitrogen (N) mineralization have attracted wide attention in the context of global climate change. Based on the data of a 42-day laboratory incubation experiment, this paper investigated the relationship between soil moisture and mineralization of C and N in soils with different vegetation types on the northern slope of the Natural Reserve Zone of Changbai Mountain. The elevation influence on soil C and N mineralization was also discussed. The results indicated that for the given vegetation type of Changbai Mountain the C and N mineralization rate, potential mineralizable C (C0) and potential rate of initial C mineralization (C₀k) all increased as the soil moisture rose. The elevation or vegetation type partially affected the soil C and N mineralization but without a clear pattern. The moisture-elevation interaction significantly affected soil C and NO₃^--N mineralization, but the effect on NH₄⁺-N mineralization was not significant. The complex mechanism of their impact on the soil C and N mineralization of Changbai Mountain remains to be studied further based on data of field measurements in the future.

Ornamental nurseries, garden centres, public gardens and urban greenery in the Czech Republic were surveyed in 2006-2009 for the presence of Phytophthora spp. and the diseases they cause on ericaceous plants. Diseased plants such as Rhododendron spp., Pieris floribunda, Vaccinium sp., and Azalea sp. showed various symptoms including leaf spot, shoot blight, twig lesions or stem, root and collar rot. Nearly 140 Phytophthora isolates were collected from symptomatic plants in different areas of the country. Of the Phytophthora spp. on ericaceous plants or in their surroundings, P. plurivora appeared to be the most common species. Herein, we focus on the most frequently occurring species, P. plurivora, and describe its morpho-physiological and pathogenicity features and confirm its identity based on ITS sequences of rDNA. In addition, we give a list of other Phytophthora spp. including P. cactorum, P. cambivora, P. cinnamomi, P. citrophthora, P. megasperma, P. multivora, P. ramorum, and P. gonapodyides that we identified on the basis of their cultural and morphological characteristics and DNA sequences. We also discuss their importance in cultivated and natural ecosystems.

Declining water is a great concern in production of rice, because rice is more sensitive to water deficiency which restricts normal rice growth resulting in enormous economic loss. A field experiment was conducted to study the effect of hydrogel in different sowing techniques of aerobic rice viz. flat, ridge, and bed sowing. Observations on soil moisture percentage before every irrigation, yield, and yield components of rice were recorded. Application of hydrogel improved soil moisture contents in all the three sowing techniques as compared to soil without hydrogel. More soil moisture contents met the crop water needs and increased the number of germinated seeds. As a consequence of more emergence and better stand establishment, the yield components were also improved increasing the yield of rice in hydrogel amended soil in all sowing techniques. However, sowing of rice on beds with hydrogel amendment was found the most effective; it not only improved the performance of aerobic rice but also enhanced growth and yield of aerobic rice more than other sowing techniques.

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.

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.

The fungus Ramularia collo-cygni is increasingly important as the causal agent of Ramularia leaf spot (RLS), a novel leaf spot disease of barley. The work aimed to identify gene resources suitable for developing new breeding lines of winter barley with improved resistance. During the first experimental period (2001-2005), RLS incidence was monitored in 711 cultivars and advanced breeding lines. Differences were detected in the intensity of symptomatic expression, but no material showed high resistance. During the second experimental period (2006-2009), response to natural RLS infection was evaluated in 19 winter barley cultivars (12 six-row and 7 two-row) registered in the Czech Republic. Highest susceptibility was detected in 6-row cvs. Luran, Laverda and Wendy while cvs Breunskylie (2-row), Merlot and Highlight (both 6-row) showed relatively lower disease incidence. High resistance was not detected. On average, 2-row cultivars showed lower intensity than 6-row cultivars and significant variation was observed among years.

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.

Nitric oxide (NO) is a gaseous diatomic molecule with a wide variety of physiological and pathological implications in plants. Presence of unpaired electron in its molecular orbital makes it highly reactive; it can react directly with metal complexes, radicals, DNA, proteins, lipids and other biomolecules. Nitric oxide (NO) and reactive oxygen species (ROS) are known to play essential role in a number of important plant physiological processes. This manuscript reviews the role of NO on these processes during various biotic and abiotic stresses.

Soil and water salinization are affecting an increasing number of countries in the world, especially in arid and semi-arid regions, and cause sensible reductions of agricultural land extension and of crop yields. Consociation with halophytic plants is a promising but not yet widely investigated strategy of salt stress reduction in crops. In this experiment, tomato plants were cultivated in saline conditions, alone and in consociation with three different halophytic species (Portulaca oleracea L.; Salsola soda L.; Atriplex hortensis L.). The salinity was brought either by the soil or by the irrigation water. Consociation with P. oleracea gave the best results in terms of increase of tomato growth and yields, while S. soda caused excessive nutritional competition against tomato due to its fast growth, undoing the positive effects of saline ions uptake. A. hortensis gave intermediate results. Salinity of water resulted in causing more severe stress on the plants, and consequently highlighted more the benefical effect of salt uptake performed by the halophytes on the main crop; salinity of soil on the contrary appeared to be less decisive, probably due to the leaching effect of the irrigation water.

We have estimated soil organic carbon and crop yield changes under distinct climate change scenarios for the Kočín farm in Slovakia. Two regional climate change scenarios, i.e. the A2 and B2 SRES emission scenarios, and a reference climate scenario have been included into the bio-physical process model EPIC to simulate the effects on the topsoil organic carbon stocks and crop yields for the period of 2010-2050. In addition, we have used the data from several fields of the Kočín farm including the soil data, crop rotational and management data as well as topographical data. The topsoil organic carbon stocks show a decreasing trend for the period of 2010-2050. Among all crop rotation systems and soil profiles, the losses over the period are 9.0%, 9.5%, and 10.7% for the reference, A2, and B2 climate scenarios, respectively. Increasing temperatures accelerate the decomposition of the soil organic carbon particularly when soils are intensively managed. The soil organic carbon changes are crop-rotation specific, which is partly due to the climate scenarios that affect the crop biomass production differently. This is shown by comparison of the crop yields. We conclude that EPIC is capable to reliably simulate effects of climate change on soil organic carbon and crop yields.

In this report a case of actinomycosis in a five-month-old Holstein calf is described. The patient displayed a hard and immobile swelling in the mandible and fever. Computed tomography (CT) imaging of the skull was performed under deep sedation and revealed an asymmetrical appearance of the mandible with the presence of intra-mandibular hypodense lesions. Haematologic and serum biochemical profiles revealed leukocytosis, neutrophilia, hypoalbuminaemia and hypergammaglobulinaemia. Treatment consisted of flushing the lesion and administration of antibiotics and non-steroidal anti-inflammatory drugs. The calf responded to therapy and had recovered almost completely four months later. The present case indicates that CT is an effective non-invasive means of identifying mandibular lesions in cattle.

Comprehensive analyses of soil properties of sites of native Scandinavian broadleaved tree species were performed in 36 habitats in East Norway. The material consisted of stands of silver birch (Betula pendula Roth.), white birch (Betula pubescens Ehrh.), black alder (Alnus glutinosa Gaertn.), speckled alder (Alnus incana Moench.), European ash (Fraxinus excelsior L.), pedunculate oak (Quercus robur L.) and sessile oak (Quercus petraea [Matt.] Liebl.). The main objective was to describe the vertical characteristics and variations in some selected soil variables of the soil profiles. Particular soil horizons of 15 Brunisolic soils, 11 Regosolic soils, 6 Gleysolic and 4 Podzolic were sampled and analyzed for soil texture, bulk density, specific density, porosity, oxidizable carbon, total nitrogen content, pH in water, exchangeable acidity, exchangeable cations and anions (Mg, Ca, Mn, Al, S, Fe, B, P and K), cation exchange capacity and base saturation. No regular patterns were found in selected soil properties when tested between various soil units in silver birch stands. Furthermore, silver birch stands were found on sites, which topsoil (i) significantly differed in their cation exchange capacities, (ii) did not differ significantly in their pH values, and (iii) mostly differed in their clay contents and (iv) mostly did not differ in BS. Differences among the Humic Regosols, Luvic Gleysols, Sombric Brunisols, Eutric Brunisols and Humo-Ferric Podzols for silver birch stands in their topmost horizons of humified organic matter intimately mixed with the mineral fraction horizons and differences among particular soil horizons for the main soil properties under all the selected broadleaved tree species stands are discussed.

The Fusarium species associated with maize are widely distributed in Malaysia. Eight Fusarium species were obtained in this country. A series of field samplings was conducted from 2006 to 2008, when 167 Fusarium isolates were obtained from maize plants in seven locations throughout Malaysia. The determination was based on micro- and macromorphological features (growth rates, colony features, mode of production of microconidia, macroconidia, conidiophores, and chlamydospores). F. proliferatum (29.9% isolates), F. semitectum (22.2% isolates), F. verticillioides (13.7% isolates), and F. subglutinans (12.6% isolates) were found out most frequently. F. equiseti, F. pseudograminearum, F. oxysporum, and F. solani were also isolated. This is the first report on the occurrence of F. equiseti, F. pseudograminearum, and F. subglutinans associated with maize plants in Malaysia.

Influence of growth regulators chlormequat chloride, ethephon, trinexapac-ethyl, and a combination of chlormequat chloride and ethephon on decreasing sunflower height was examined in the years 2006-2009. Height was reduced by as much as 63 cm by double application of chlormequat chloride (915 g/ha) + ethephon (465 g/ha) at early and later growth stage (BBCH 32 and 50). Trinexapac-ethyl (375 g/ha) did not affect the height. One-time application of chlormequat chloride (1440-2160 g/ha), chlormequat chloride (458 g/ha) + ethephon (233 g/ha) (BBCH 30 or 50), or ethephon (480 g/ha) (BBCH 30) was sufficient for a ca 30 cm reduction during flowering, but this effect did not last until harvest. With double application (BBCH 30 and 50), reduction lasted until harvest. For ethephon (480 g/ha), application at BBCH 50 reduced height by as much as 35 cm and lasted until harvest. Combining a lower rate of ethephon with ammonium sulfate was effectively equivalent to using a full rate. Flower head diameter at maturity showed no significant negative influence compared to the control. In 2008 and 2009, a delay in flowering onset was observed after applying growth regulators.

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 study is aimed at investigating the effect of different vineyard soil management systems on soil erosion and earthworm (Lumbricidae) population. Three soil management systems were investigated: permanent green cover (control), straw-cover and periodic soil tillage. Inter-row periodic soil tillage was applied in 2002 and 2003 (May and August), and straw-cover in May 2002. Periodic soil tillage resulted in increased erosion, i.e. 1746 kg/ha of soil/per year, on average. The greater portion of erosive events occurred after tillage in summer (August 2002), which was accompanied by heavy rainfall and slow renewal of grass cover (slower than in spring). The lowest average amount of soil erosion was observed in the treatment with straw-cover (56 kg/ha per year). This management system provided better environment for earthworm populations, most of which were found close to the soil surface, especially in the dry year 2003. In periodical soil tillage, the majority of earthworms were found in the soil horizon not disturbed by the tillage, i.e. at the depth of 10-20 cm. The lowest number of earthworms (only 2 per m²) was recorded in the herbicide intra-row strip.

The noctuid C. trapezina (CT) has been considered an occasional predator of other Lepidoptera larvae. Functional/numerical response of predator and/or prey was estimated using 27 years of time-series data from Slovakia and stepwise multiple regression models (SMRM). SMRM were used to examine a possible delayed density-dependent feedback. We constructed 12 order-three autoregressive models [AR(3)] for CT and candidate prey. Independent variables were abundance of C. trapezina and abundance of candidate prey in lags 1, 2, and 3. Model variants were: (1) predation on free feeder models (FFM); (2) predation on shelter feeder models (SFM); (3) predation on the sum of 8 species models (S8M); (4) predation on all Lepidoptera models (ALM). Models were constructed for three areas (created by grouping sites based on significant correlations among CT populations). Additional comparative models were constructed for another three noctuid species and one geometrid species to compare their regression parameters under the same conditions as for CT. In total, 48 AR(3) SMRM were constructed for comparative species. A negative response of shelter feeders was found in models mainly for CT. We also found the positive response of CT growth rate to abundance of shelter feeders in lag 3 on two out of three models. This pattern was not found for any other comparison of species in the analysis. Possible mechanisms for these results are discussed.

Mycobacterium pinnipedii causes tuberculosis in free-living and captive pinniped species throughout the world. We report on the isolation of this M. tuberculosis complex (MTC) member from an imported male Southern sea lion (Otaria flavescens) in a zoo in the Czech Republic. Nodular granulomatous lesions were found in the lungs, pleura and mesenteric lymph nodes of this animal and M. pinnipedii was isolated from lung, mesenteric and submandibular lymph nodes. Identification of the isolates was confirmed using two independent molecular methods. Direct IS6110 PCR amplification confirmed the presence of an MTC member in these samples. Faecal and oral swabs from three living female sea lions were examined using direct IS6110 PCR and were all found to be negative. Twelve environmental samples were examined using direct microscopy after Ziehl-Neelsen staining and culture methods along with direct IS6110 PCR examination, all yielding negative results. Seven people that came into close contact with the infected animal were examined using a skin tuberculin test and chest x-ray, revealing no evidence of infection by a MTC member.

Occurrences of pea aphids and their natural enemies (syrphids, mummies caused by entomopathogenic fungi Beauveria sp. and by the parasitic wasp Aphidius ervi) were compared in monocultures and mixtures of field peas and spring cereals in three seasons (2008-2010). At the beginning of colonisation, the occurrence of aphids was not substantially influenced by intercropping with cereals. However, the numbers of pea aphids located on inflorescences started to decline earlier in mixtures compared with monoculture. More syrphids (eggs + larvae) were found in mixtures than in monoculture, and more syrphid eggs were found in young aphid colonies (10 to 20 individuals) in mixtures. Intercropping did not influence the occurrence of fungal mummies (Beauveria sp.), but mixtures tended to have more aphid colonies infested by A. ervi in 2008 and 2009.

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.

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.

Climate change is expected to influence the distribution and population dynamics of many insect pests, with potential severe impacts on forests. Spruce bark beetle Ips typographus (L.) (Col.: Curculionidae, Scolytinae) is the most important forest insect pest in Europe whose development is strictly regulated by air temperature. Therefore, climate change is anticipated to induce changes in the pest's distribution and development. We used the PHENIPS model to evaluate climate change impacts on the distribution and voltinism of spruce bark beetle in the Czech Republic. Two future time periods - 2025-2050 (near future) and 2075-2100 (distant future) - are addressed. The period 1961-1990 is used as the reference. We found that while a two-generation regime dominated in the Czech Republic in the reference period, significant three-generation regime regions are projected to appear in the near future. In the distant future, the three-generation regime can be expected to occur over all existing coniferous stands in the Czech Republic. The analysis of altitudinal shift of n-generation regime regions indicates noticeable expansion of Ips typographus development to higher elevations, leading for example to disappearance of one-generation regime regions in the distant future. Uncertainties and limitations of the presented findings are discussed as well.

Grazing-induced variations in vegetation may either accelerate or reduce soil carbon storage through changes in litter quantity and quality. Here, a three-year field study (2005-2007) was conducted in Tibetan alpine meadow to address the responses of surface soil (0-15 cm) organic carbon (SOC) storage in the plant growing season (from May to September) to varying grazing intensity (represented by the residual aboveground biomass, with G₀, G₁, G₂, and G₃ standing for 100%, 66%, 55%, and 30% biomass residual, respectively), and to explore whether grazing-induced vegetation changes depress or facilitate SOC storage. Our results showed that: (i) Higher grazing intensity resulted in lower biomass of grasses and sedges, lower root biomass, and in a change in plant community composition from palatable grasses and sedges to less palatable forbs. (ii) Increased grazing reduced the SOC content and storage with only G₃ showing an SOC loss during the plant growing season. (iii) Soil organic carbon storage exhibited a highly positive correlation with the residual aboveground biomass and root biomass. Our results imply that a grazing-induced reduction in plant biomass productivity and changes in species composition would depress soil carbon storage, and that an increase in grazing pressure can lead to a gradual change of alpine meadow soils from being 'carbon sinks' to become 'carbon sources'.