The effects of fertilization on the health status,nutrition and growth of Norway spruce forests with yellowing symptoms

We studied the effects of magnesium (Mg) NPK fertilizer applied in 2000 to maturing Norway spruce (Picea abies /L./ Karst.) stands with yellowing symptoms and situated on poor acidified soils in the ?umava mountains (the Czech Republic). Long-term defoliation, nutrient content in the foliage and diameter increment were evaluated in three specific variants: yellowing trees, trees without yellowing symptoms and fertilized trees. The results indicate differences in soil characteristics, nutrient content and radial growth with response to climate. Fertilization increased Mg content and base saturation in the soil and decreased the amount of exchangeable aluminum and hydrolytic acidity. Differences were significant especially in magnesium, calcium and phosphorus contents in the foliage of yellowing trees. There was also a significant difference in manganese content; yellowing trees showed deficiency in comparison with both fertilized and unfertilized healthy trees. Two years after the initial fertilization (to present), defoliation and yellowing symptoms in the unfertilized yellowing trees were more pronounced compared to other variants. These symptoms were more influenced by fertilization than foliation. The duration of significant positive effects of fertilization on diameter increment lasted for a shorter time than the effect on foliage. Simultaneously, higher sensitivity to climatic factors was observed in the fertilized trees.     

Impact of water scarcity on spruce and beech forests

One of the greatest threats posed by ongoing climate change may be regarded the drought caused by changes in precipitation distribution. The aim of presented study was to characterize reactions to dry conditions and conditions without drought stress on gross primary production (GPP) and net ecosystem production (NEP) of spruce and beech forests, as these two species dominate within the European continent. Daily courses of GPP and NEP of these two species were evaluated in relation to an expected decrease in CO2 uptake during dry days. The occurrence of CO2 uptake hysteresis in daily production was also investigated. Our study was performed at Bily Kriz(spruce) and Stitna(beech) mountain forest sites during 2010–2012 period. We applied eddy covariance technique for the estimation of carbon fluxes, vapor pressure deficit and precipitation characteristics together with the SoilClim model for the determination of drought conditions, and the inverse of the Penman–Monteith equation to compute canopy conductance. Significant differences were found in response to reduced water supply for both species. Spruce reacts by closing its stomata before noon and maintaining a reduced photosynthetic activity for the rest of the day, while beech keeps its stomata open as long as possible and slightly reduces photosynthetic activity evenly throughout the entire day. In the spruce forest, we found substantial hysteresis in the light response curve of GPP. In the beech forest, the shape of this curve was different: evening values exceeded morning values.     

Genetic diversity,phylogenetic position and morphometric analysis of Astacus colchicus (Decapoda,Astacidae): a new insight into Eastern European crayfish fauna

The phylogeny of European crayfish fauna, especially with respect to Eastern European species, is still far from being completely resolved. To fill this gap, we analyzed most of the European crayfish species focusing on the phylogenetic position of the endemic crayfish Astacus colchicus, inhabiting Georgia. Three mitochondrial and one nuclear marker were used to study evolutionary relationships among European crayfish species, resulting in the unique phylogenetic position of A. colchicus indicating independent species status to A. astacus. Phylogenetic analyses revealed a deep molecular divergence of A. colchicus in comparison to A. astacus (6.5–10.9% in mtDNA and 1.1% in nDNA) as well as to Pontastacus leptodactylus and P. pachypus (5.5–10.0% in mtDNA and 1.4–2.4% in nDNA). Absent ventral process on second male pleopod and abdominal somites II and III with pleura rounded lacking prominent spines clearly indicate taxonomic assignment to the genus Astacus; however, the species is distributed almost in the middle of Ponto-Caspian area typical by occurrence of the genus Pontastacus. Several morphological indices linked to head length, carapace, and total body length and width were found to demonstrate apparent differences between A. colchicus and A. astacus. Although this study provides a novel insight into European crayfish phylogeography, we also point out the gaps in comprehensive study of the P. leptodactylus species complex, which could reveal details about the potential species status of particular species and subspecies within this genus.     

Newly identified host range of European mountain ash ringspot‐associated virus (EMARaV) and its distribution in the Czech Republic

It has been previously shown that European mountain ash ringspot‐associated virus (EMARaV), a multipartite, negative‐strand RNA plant virus, is pathogenic for European mountain ash (Sorbus aucuparia L.). However, its transmissibility to and replication in other host species remains poorly understood. In this work, we performed experimental inoculations of seventeen virus‐tested species and interspecies hybrids of subfamily Maloideae (family: Rosaceae) with buds from EMARaV‐infected S. aucuparia trees. Surprisingly, a majority of the graft‐inoculated tree species, for instance Sorbaronia, Aronia and Amelanchier, developed symptoms typical for EMARaV infection. These symptoms included chlorotic spots of various size and shape and mottling on leaves but not on flowers and fruits. The propagation of EMARaV in graft‐inoculated tree species was subsequently confirmed by molecular detection tools. Based on these results, we carried out a systematic survey throughout the Czech Republic and identified the presence of EMARaV in wild growing trees in all explored regions, with massive disease infestation in several locations. More importantly, EMARaV infection was newly detected in S. aucuparia subsp. moravica, S. aucuparia × Crataegus sanguinea cv. Granatnaja, (Sorbus aria × Aronia arbutifolia) × S. aucuparia cv. Burka, cv. Finskaja (a Sorbus hybrid of unknown origin) and Aronia melanocarpa; all these EMARaV‐infested trees were grown in production orchards. The sequencing of the nucleocapsid (NC)‐coding gene from several of these EMARaV isolates provided insight into the population structure and phylogenetic relationships of the EMARaV variants occurring in the Czech Republic. Together, our biological and molecular findings extend our knowledge on the host range of EMARaV and provide the first evidence of its natural occurrence in hosts dissimilar to S. aucuparia.     

Engineering properties of red clover (Trifolium pratense L.) seeds

Selected engineering properties of seeds of four red clover varieties were studied. The seeds of diploid and tetraploid forms were statistically different in terms of true and bulk density, porosity, volume, 1000 seed weight, equivalent diameter and yellowness index. The volume, 1000 seed weight and equivalent diameter were found to be statistically higher for tetraploid than for diploid forms. The accuracy of varietal classification based on the physical properties of seeds was found to be most satisfactory. Varieties of Bona and Jubilatka were identified with 100% accuracy based on the physical properties of seeds. Bona was the most conducive variety for the classification of red clover seeds based on four groups of engineering properties. The relationships between groups of properties described by total redundancy did not exceed 50% for any of variable pairs.     

Microstructure of the small intestine in broiler chickens fed a diet with probiotic or synbiotic supplementation

The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one‐day‐old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n = 120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti‐bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42 days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.     

Quality of Wine Grape Cultivars Grown in Czech Republic

This research aims to make an analysis of significant parameters in wine grape from Czech Republic. It was evaluated pH, content of sugar, ascorbic acid, titratable acidity, total phenolic content and texture properties. For analyzes 5 samples of wine grape were used, harvested during the three periods. The results show that during the ripening of wine grapes there were changes of selected qualitative parameters, particularly of total polyphenols, sugar and some varieties of wine grape also ascorbic acid (significantly in the variety ’Grüner Veltliner’, ’Chardonnay’, ’Pinot Blanc’). Pronounced changes qualitative parameters were among wine grapes harvested the 1st and 2nd seasons. Changes in textural properties also occurred during the harvest and for most varieties between 2nd and 3rd period of harvest. The PCA grouped chemical parameters of wine grape in independent sets and can be used as assessment tool of wine cultivars.     

Post Hoc Assessment of Stand Structure Across European Wood-Pastures: Implications for Land Use Policy

Europe’s woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.     

Determination of growth-stage-specific crop coefficients (KC) of maize and sorghum

A ratio of crop evapotranspiration (ET_C) to reference evapotranspiration (ET_O) determines a crop coefficient (K_C) value, which is related to specific crop phenological development to improve transferability of the K_C values. Development of K_C can assist in predicting crop irrigation needs using meteorological data from weather stations. The objective of the research was conducted to determine growth-stage-specific K_C and crop water use for maize (Zea Mays) and sorghum (Sorghum bicolor) at Texas AgriLife Research field in Uvalde, TX, USA from 2002 to 2008. Seven lysimeters, weighing about 14 Mg, consisted of undisturbed 1.5 m × 2.0 m × 2.2 m deep soil monoliths. Six lysimeters were located in the center of a 1-ha field beneath a linear-move sprinkler system equipped with low energy precision application (LEPA). A seventh lysimeter was established to measure reference grass ET_O. Crop water requirements, K_C determination, and comparison to existing FAO K_C values were determined over a 3-year period for both maize and sorghum. Accumulated seasonal crop water use ranged between 441 and 641 mm for maize and between 491 and 533 mm for sorghum. The K_C values determined during the growing seasons varied from 0.2 to 1.2 for maize and 0.2 to 1.0 for sorghum. Some of the values corresponded and some did not correspond to those from FAO-56 and from the Texas High Plains and elsewhere in other states. We assume that the development of regionally based and growth-stage-specific K_C helps in irrigation management and provides precise water applications for this region.