Infection experiments with Gremmeniella abietina on seedlings of Norway spruce and Scots pine

Conidia of Gremmeniella abietina infected and caused disease symptoms in annual shoots of both Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) seedlings. In Norway spruce shoots the infection remained largely latent, with only a few seedlings showing symptoms. Mycelial growth inside the shoots was faster in Scots pine than in Norway spruce and was favoured by low temperature in both hosts. The shoots of Norway spruce seedlings had higher endophyte populations than those of Scots pine, and the populations were decreased by low temperatures. Reductions in the normal epiphytic or endophytic flora by acid mist treatments seemed to favour the development of G. abietina.     

Occurrence and pathogenicity of fungi in necrotic and non-symptomatic shoots of declining common ash (<Emphasis Type="Italic">Fraxinus excelsior</Emphasis>) in Sweden

Currently, massive dieback of Fraxinus excelsior is observed in countries of eastern, northern and central Europe, and the reasons for it are unclear. The aims of the present work were (a) to study fungal communities in declining F. excelsior crowns; (b) to clarify role of fungi in the decline. Shoots from symptomatic crowns were collected in four localities in central Sweden, and distributed into the following categories: (a) visually healthy; (b) initial necroses; (c) advanced necroses; (c) dead tops. The most frequently isolated fungi were Gibberella avenacea, Alternaria alternata, Epicoccum nigrum, Botryosphaeria stevensii, Valsa sp., Lewia sp., Aureobasidium pullulans and Phomopsis sp., and these taxa were consistently found in shoots of all four symptomatic categories. Forty-eight taxa of other fungi were isolated, and fungal diversity was not exhausted by the sampling effort. The same taxa of fungi were dominant in F. excelsior shoots of different symptomatic categories, and moderate to high similarity of fungal communities was observed in shoots despite the symptoms. Forty-four isolates from 24 fungal taxa were used for artificial inoculations of 277 1-year-old F. excelsior seedlings in bare root nursery. After 2 years, only four fungi caused symptomatic necroses of bark and cambium: A. alternata, E. nigrum, Chalara fraxinea and Phomopsis sp. The most pathogenic was C. fraxinea, inducing symptoms on 50% of inoculated trees, while three other fungi caused necroses on 3–17% of inoculated trees. Infection biology of C. fraxinea and environmental factors determining susceptibility of F. excelsior to decline deserve future investigations.     

The combined effect of wetting ability and durability on outdoor performance of wood: development and verification of a new prediction approach

Comprehensive approaches to predict performance of wood products are requested by international standards, and the first attempts have been made in the frame of European research projects. However, there is still an imminent need for a methodology to implement the durability and moisture performance of wood in an engineering design method and performance classification system. The aim of this study was therefore to establish an approach to predict service life of wood above ground taking into account the combined effect of wetting ability and durability data. A comprehensive data set was obtained from laboratory durability tests and still ongoing field trials in Norway, Germany and Sweden. In addition, four different wetting ability tests were performed with the same material. Based on a dose–response concept, decay rates for specimens exposed above ground were predicted implementing various indicating factors. A model was developed and optimised taking into account the resistance of wood against soft, white and brown rot as well as relevant types of water uptake and release. Decay rates from above-ground field tests at different test sites in Norway were predicted with the model. In a second step, the model was validated using data from laboratory and field tests performed in Germany and Sweden. The model was found to be fairly reliable, and it has the advantage to get implemented into existing engineering design guidelines. The approach at hand might furthermore be used for implementing wetting ability data into performance classification as requested by European standardisation bodies.     

Rice production and food security in Asian Mega deltas—A review on characteristics,vulnerabilities and agricultural adaptation options to cope with climate change

Asian Mega deltas (AMDs) are among the world´s most important rice-growing areas and vital for food security. This review describes the major environmental and agricultural characteristics as well as current and future threats to food production and livelihood, using three AMDs as examples, namely the Ganges–Brahmaputra delta in Bangladesh, the Ayeyarwady delta in Myanmar and the Mekong River delta in Vietnam. In addition, we analysed the most widely used agricultural adaptation methods in these areas. The major threat to agriculture is salinity intrusion and water scarcity, which consequently leads to a shortage of irrigation water and yield reduction. The most common applied agricultural adaptation strategies are the use of salt-tolerant varieties and the adjustment of cropping calendars, as well as the use of water-saving technologies. It was found that there are many concepts that address individual problems, but a comprehensive and integrated concept for delta regions to adapt to climate change is still missing.     

Improving iron bioavailability and nutritional value of maize (Zea mays L.) in sulfur-treated calcareous soil

Soil factors such as pH, calcium, carbonate, and bicarbonate precipitation products in calcareous soils reduce iron (Fe) availability to crops and limit grain Fe concentrations. In the present greenhouse study, we evaluated the potential of Fe fertilizer amendments combined with organic amendments, like biochar (BC) and poultry manure, in sulfur (S)-treated low pH calcareous soils (pH_S1) to assess Fe biofortification of maize. Elemental sulfur (S) was used both for lowering soil pH and Fe solubilization. Soil pH was successfully lowered down from 7.8 to 6.5 by S application at the rate of 2.5 g kg^?1 soil. Pot experiment results revealed that Fe fertilizer combined with BC and S (pH_S1) significantly increased root and shoot dry weight, grain weight, photosynthetic rate, transpiration rate, and stomatal conductance by 69%, 86%, 28%, 74%, 57%, and 33%, respectively, relative to the control. Similarly, combined application of Fe + BC in S-amended (pH_S1) soil increased starch (34%), protein (64%), and fat (1 fold) while antinutrient phytate and polyphenols were decreased up to 29% and 40%, respectively, over control. Regarding the maize nutrients profiles, application of Fe with BC gave the maximum increase of Fe and ferritin was increased 1.7 fold at pH_S1. The results of this study showed that Fe fertilization with BC at pH_S1 soil is beneficial for crop growth and Fe bioavailability.     

Evaluation of techniques for the recovery of live intestinal Trichinella spiralis worms from experimentally infected foxes

Previously described methods for the recovery of intestinal Trichinella worms from rodents are not feasible when applied in larger experimental animals such as foxes. In this study,worm recovery by standard technique of simple incubation of the intestine in saline was compared to embedment of the intestine in an agar gel. The small intestines of Trichinella spiralis infected foxes (4-5 days post inoculation) were slit lengthwise and the two corresponding halves were processed with one of the two incubation methods.Worms were recovered from all samples, and the total worm recovery ranged from 0.2-4.4% of the infection dose. The samples from the standard incubation were very unclear and time consuming to count compared with samples from the agar gel embedment,in which the intestinal debris were kept inside the agar. As the agar gel technique generally yielded higher numbers of worms than the corresponding standard incubation sample, it is with some optimisation, recommended for recovery of intestinal Trichinella worms from foxes.     

转型中的亚洲林业(续一)

在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。     

Storage stability of microencapsulated cloudberry ( Rubus chamaemorus ) phenolics

Cloudberries ( Rubus chamaemorus ) contain phenolics (mainly ellagitannins), which have recently been related to many valuable bioactivity properties. In general, phenolics are known to react readily with various components, which may create an obstacle in producing stable functional components for food and pharmaceutical purposes. In this study, the aim was to improve the storage stability of cloudberry phenolic extract by microencapsulation. The phenolic-rich cloudberry extract was encapsulated in maltodextrins DE5-8 and DE18.5 by freeze-drying. Water sorption properties and glass transition temperatures (T(g)) of microcapsules and maltodextrins were determined. Microcapsules together with unencapsulated cloudberry extract were stored at different relative vapor pressures (0, 33, and 66% RVP) at 25 degrees C for 64 days, and storage stability was evaluated by analyzing phenolic content and antioxidant activity. Compared to maltodextrin DE18.5, maltodextrin DE5-8 had not only higher encapsulation yield and efficiency but also offered better protection for phenolics during storage. Without encapsulation the storage stability of cloudberry phenolics was weaker with higher storage RVP. Microencapsulation improved the storage stability of cloudberry phenolics. The physical state of microcapsules did not have a significant role in the stability of cloudberry phenolics because phenolic losses were observed also in amorphous glassy materials. The antioxidant activity of the microencapsulated cloudberry extract remained the same or even improved slightly during storage, which may be related to the changes in phenolic profiles.     

Handheld mechanical nociceptive threshold testing in dairy cows – intra‐individual variation,inter‐observer agreement and variation over time

ObjectiveTo examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed.Study designProspective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time.AnimalsOne hundred and fifteen healthy, loose-housed Danish Holstein cattle.MethodsWe evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0–10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0–1000 gf). Each cow received 5–6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant.ResultsThe CVs did not differ [range 0.34–0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01).Conclusion and clinical relevanceAll methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia.