Efficient application of in vitro anther culture for different European winter wheat (Triticum aestivum L.) breeding programmes

The efficiency of our anther culture protocol was tested with high‐ and low‐responding genotypes, ‘Svilena’ and ‘Berengar’, and 93 F₁ winter wheat crosses in 2010 and 2011. Based on data for these genotypes, the effect of genotype influenced the number of embryo‐like structures, regenerated plantlets and green plantlets, while the number of albino plantlets was affected by genotype, year and environmental factors. Although genotype also influenced the production of green plantlets from breeding crosses, with green plantlets per 100 anthers ranging from 0.04 to 28.67, the average regeneration rate over all crosses was 5.3 green plantlets/100 anthers, which resulted in a total of 11 416 well‐rooted green plantlets. The survival rate of green plantlets following acclimatization was 97.21% in 2010 and 96.34% in 2011. In this study, the phenomenon of albinism and genotype dependency did not hinder the production of more than five thousand green plantlets each year. In our experiments, anther culture proved to be an efficient method in winter wheat breeding programmes with lower costs than alternative technologies.     

Arsenic mobility and groundwater extraction in Bangladesh

High levels of arsenic in well water are causing widespread poisoning in Bangladesh. In a typical aquifer in southern Bangladesh, chemical data imply that arsenic mobilization is associated with recent inflow of carbon. High concentrations of radiocarbon-young methane indicate that young carbon has driven recent biogeochemical processes, and irrigation pumping is sufficient to have drawn water to the depth where dissolved arsenic is at a maximum. The results of field injection of molasses, nitrate, and low-arsenic water show that organic carbon or its degradation products may quickly mobilize arsenic, oxidants may lower arsenic concentrations, and sorption of arsenic is limited by saturation of aquifer materials.     

Physiological response to pruning severity in Eucalyptus regnans plantations

The photosynthetic response to pruning was measured in two Eucalyptus regnans stands, aged 2 and 3 years, located in areas of high productivity on the coast of the province of Arauco, Chile. Variables such as rates of CO₂ assimilation and stomatal conductance were measured in three ages of foliage on trees with different pruning severity treatments, which corresponded to the removal of 0 % (control), 30, 50 and 70 % of live crown length. The 2-year-old stand measurements were performed at the time of pruning and 6, 10, 14 and 18 weeks later, and the 3-year stand, 5, 9, 18 and 28 weeks after pruning. In both trials, significant differences were found between the foliage ages for all instances of measurement showing the mature foliage the highest values up to 30 % higher than old foliage. There were also significant differences between pruning severity treatments in both trials in which, in general, the highest values of CO₂ assimilation were observed among the highest pruning severity treatments with values up to 40 % higher than the unpruned trees.     

Water quality and stocking density as stressors of channel catfish (Ictalurus punctatus Raf.)

The influences of heated recirculated water and well water on three stocking densities of channel catfish (Ictalurus punctatus Raf.) were compared, based on several physiological and hematological parameters. Controls were kept in well water only. The leucocyte count of fish kept in well water generally decreased, and their thrombocyte, lymphocyte and granulocyte counts were lower at higher stocking densities. In addition, a slight hemoconcentration was observed. The fish kept in recirculated water showed a decrease only in thrombocyte count. Plasma cortisol and blood glucose did not change and in all groups were at a level characteristic of resting fish. In contrast, the blood lactate levels were always high. This may have been caused by the anesthetization. The alterations found are regarded as symptoms of the “general adaptation syndrome” induced by the stocking rates. High lymphocyte and granulocyte counts among the fish in reused water are signs of local adaptations to reduced water quality.     

Multifunctionality of floodplain landscapes: relating management options to ecosystem services

The concept of green infrastructure has been recently taken up by the European Commission for ensuring the provision of ecosystem services (ESS). It aims at the supply of multiple ESS in a given landscape, however, the effects of a full suite of management options on multiple ESS and landscape multifunctionality have rarely been assessed. In this paper we use European floodplain landscapes as example to develop an expert based qualitative conceptual model for the assessment of impacts of landscape scale interventions on multifunctionality. European floodplain landscapes are particularly useful for such approach as they originally provided a high variety and quantity of ESS that has declined due to the strong human impact these landscapes have experienced. We provide an overview of the effects of floodplain management options on landscape multifunctionality by assessing the effects of 38 floodplain management interventions on 21 relevant ESS, as well as on overall ESS supply. We found that restoration and rehabilitation consistently increased the multifunctionality of the landscape by enhancing supply of provisioning, regulation/maintenance, and cultural services. In contrast, conventional technical regulation measures and interventions related to extraction, infrastructure and intensive land use cause decrease in multifunctionality and negative effects for the supply of all three aspects of ESS. The overview of the effects of interventions shall provide guidance for decision makers at multiple governance levels. The presented conceptual model could be effectively applied for other landscapes that have potential for a supply of a high diversity of ESS.     

Evaluation of genomic approaches for marker‐based improvement of lodging tolerance in triticale

Lodging tolerance is an important agronomic trait as it can have a severe negative impact on grain yield and quality. Here, we used a large mapping population of 647 doubled haploid triticale lines derived from four families to dissect the genetic architecture underlying lodging tolerance and to assess different approaches for a genomics‐based improvement of the trait. The plants were evaluated for lodging in two environments and genotyped with 1710 genomewide DArT markers. We observed a large genotypic variation for lodging and transgressive segregation in all families. Employing two complementary QTL mapping approaches, we identified both main effect and epistatic QTL. Using cross‐validation, we showed that the proportion of genotypic variance explained by the detected QTL is low, thus limiting the efficiency of marker‐assisted selection to improve this trait. By contrast, the cross‐validated predictive ability of genomic prediction was approximately twice as high as that of the QTL‐based selection approaches. In conclusion, our results show that lodging tolerance is a complex trait that can be improved by classical breeding but also assisted by marker‐based approaches.     

Potential habitat connectivity of European bison (Bison bonasus) in the Carpathians

Habitat connectivity is important for the survival of species that occupy habitat patches too small to sustain an isolated population. A prominent example of such a species is the European bison (Bison bonasus), occurring only in small, isolated herds, and whose survival will depend on establishing larger, well-connected populations. Our goal here was to assess habitat connectivity of European bison in the Carpathians. We used an existing bison habitat suitability map and data on dispersal barriers to derive cost surfaces, representing the ability of bison to move across the landscape, and to delineate potential connections (as least-cost paths) between currently occupied and potential habitat patches. Graph theory tools were then employed to evaluate the connectivity of all potential habitat patches and their relative importance in the network. Our analysis showed that existing bison herds in Ukraine are isolated. However, we identified several groups of well-connected habitat patches in the Carpathians which could host a large population of European bison. Our analysis also located important dispersal corridors connecting existing herds, and several promising locations for future reintroductions (especially in the Eastern Carpathians) that should have a high priority for conservation efforts. In general, our approach indicates the most important elements within a landscape mosaic for providing and maintaining the overall connectivity of different habitat networks and thus offers a robust and powerful tool for conservation planning.     

Difference in spatiotemporal patterns of wildlife road-crossings and wildlife-vehicle collisions

Human–wildlife conflicts like wildlife–vehicle collisions pose major challenges for the management and conservation of mobile wildlife in human-dominated landscapes, particularly when large species are involved. Mitigation measures to reduce risk of collisions may be based on information given by wildlife movement and collision data. To test whether movement and collision data indicate different spatiotemporal risk zones, we predicted year-around probabilities of road-crossings of GPS-marked female moose (Alces alces) (n = 102), and compared them with spatiotemporal patterns of police recorded moose-vehicle collisions (n = 1158). Probability of moose road-crossings peaked in May, June, and between mid November and the beginning of January, i.e. during moose migration. Moose-vehicle collisions were more likely during autumn and winter. Comparing environmental attributes of crossing and collision sites showed significant differences. The likelihood of collisions increased with the abundance of human-modified areas and higher allowed speed, and was lower on forest roads. We found that animal movement data alone are insufficient to predict collision risk zones, while analyses of collision data alone overestimate the collision risk in certain habitats. Our findings suggest that higher collision risk is largely due to low light and poor road surface conditions rather than to more animal road-crossings. This suggests that efforts to reduce wildlife collisions should focus on driver attitudes and road conditions rather than animal movement, and any efforts to model the collision risk will require actual collision data, and not just movement data.     

Boron foliar fertilization of soybean and lychee: Effects of side of application and formulation adjuvants

Experiments to assess the rate of absorption and translocation of foliar‐applied, isotopically labeled boric acid (BA) were carried out with lychee (Litchi chinensis Sonn.) and soybean (Glycine max [L.] Merr.) plants. Boron (B) absorption and translocation within the plant, one week after treatment, was investigated after adding to the boric acid (BA solutions 0.5 mM CaCl₂ and/or 50 or 500 mM sorbitol). The contribution of stomata to the absorption process was assessed by applying the solutions either to the adaxial or to the abaxial leaf side. Both plant species differed greatly in total absorption rates. The adaxial leaf surface (lacking stomata) of lychee leaves was nearly impermeable, while the stomatous abaxial surface was permeable to BA solutions. In this species, no translocation of ¹⁰B to other leaf parts and no effect of adjuvants in increasing ¹⁰B absorption were recorded. In contrast, ¹⁰B was absorbed both by adaxial and abaxial leaf surfaces of soybean leaves. Boron concentrations measured in treated soybean leaves were sixfold higher after application to the abaxial as compared to the adaxial leaf surface. The addition of adjuvants significantly enhanced the rate of ¹⁰B absorption, but not its translocation within the plant. Treatments containing 500 mM sorbitol led to increased ¹⁰B absorption and enhanced acropetal ¹⁰B movement, whereas adding only 50 mM sorbitol had no significant effect. Application of 0.5 mM CaCl₂ in combination with 500 mM sorbitol decreased the rate of ¹⁰B absorption, compared to the performance of 500 mM sorbitol alone. Basipetal ¹⁰B translocation was very limited. A distinct effect of B‐sorbitol complexes on B translocation apart from the pure adjuvant effect could not be discerned in this investigation.