Borkenkäferbekämpfung an Alleebaumpflanzungen im Sinne der guten fachlichen Praxis im Pflanzenschutz

Zusammenfassung Zur gezielten Anwendung von Insektiziden gegen Borkenkäfer an Ziergehölzen sind Pyrethroid-Präparate zugelassen, die in Streichapplikation aufgebracht werden sollen. Mit Hilfe eines im Handel angebotenen Kleingerätes wurde vom Autor und von Garten- und Landschaftsbau- bzw. Baumschul-Unternehmen die Anwendung praktiziert und die gute Verwendbarkeit des technischen Hilfsmittels festgestellt. Auch die Anwendung eines zur Docht-Streichbehandlung zugelassenen Herbizides wurde erprobt. Ökonomische und ökologische Vorteile des Gerätes im Sinne der guten fachlichen Praxis werden aufgezeigt.     

Nitrogen uptake from 15N-enriched fertilizer by four tree crops in an Amazonian agroforest

Mixed tree cropping systems have been proposed for sustainable nutrient management in the humid tropics. Yet, the nutrient interactions between intercropped trees have not been addressed sufficiently. In the present study we compare the temporal and spatial patterns of the uptake of applied ¹⁵N by four different tree crops in a mixed tree cropping system on a Xanthic Ferralsol in central Amazônia, Brazil, during one year. Most of the N uptake occurred during the first two weeks. Very little N was recovered by peach palm (Bactris gasipaes), more by cupuassu (Theobroma grandiflorum) and annatto (Bixa orellana) and most by Brazil nut (Bertholletia excelsa). Due to tree pruning the total accumulation of applied ¹⁵N in the above-ground biomass of annatto decreased throughout the year. It remained constant in cupuassu and peach palm and increased in Brazil nut. Brazil nut showed an extensive root activity and took up more fertilizer N applied to neighboring trees than from the one applied under its own canopy in contrast to the other three tree crops. Therefore, trees with wide-spread root systems may not need to receive N fertilizer directly but can take up N applied to other trees in the mixed cropping system. This means that such trees may effectively decrease N leaching when intercropped with trees that have dormant periods or places with low N uptake, but also exert considerable resource competition.This revised version was published online in November 2005 with corrections to the Cover Date.     

Tracer methods to assess nutrient uptake distribution in multistrata agroforestry systems

Separate assessment of nutrient uptake by individual plants in mixed cropping with trees is impossible without tracer techniques. The different ¹⁵N-to-¹⁴N isotope ratio of atmospheric and soil N can be used to study the contribution of biologically fixed N to the nutrition of associated trees. In most cases, the assessment of nutrient uptake distribution is an appropriate way of evaluating how to improve the transfer of biologically fixed N. Radioisotopes (e.g., ³²P), stable isotopes (e.g., ¹⁵N) and rare elements (e.g., Sr) can be used to determine relative root activity distribution by applying the tracer to different soil depths or distances from trees. A broadcast application of the tracer instead of point application makes it possibe to calculate uptake values per unit area. The direct determination of nutrient pathways with such robust experiments offers considerable advantages for improving nutrient use efficiency and complementarity in multistrata agroforestry systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Urinary and Plasma Catecholamines and Metanephrines in Dogs with Pheochromocytoma,Hypercortisolism, Nonadrenal Disease and in Healthy Dogs

Background

Diagnosis of pheochromocytoma (PC) is based on a combination of clinical suspicion, finding an adrenal mass, increased plasma, and urine concentrations of catecholamine metabolites and is finally confirmed with histopathology. In human medicine, it is controversial whether biochemically testing plasma is superior to testing urine.

Objectives

To measure urinary and plasma catecholamines and metanephrines in healthy dogs, dogs with PC, hypercortisolism (HC), and nonadrenal diseases (NAD) and to determine the test with the best diagnostic performance for dogs with PC.

Animals

Seven PC dogs, 10 dogs with HC, 14 dogs with NAD, 10 healthy dogs.

Methods

Prospective diagnostic clinical study. Urine and heparin plasma samples were collected and stored at −80°C before analysis using high‐pressure liquid chromatography (HPLC) coupled to electrochemical detection or tandem mass spectrometry were performed. Urinary variables were expressed as ratios to urinary creatinine concentration.

Results

Dogs with PC had significantly higher urinary normetanephrine and metanephrine : creatinine ratios and significantly higher plasma‐total and free normetanephrine and plasma‐free metanephrine concentrations compared to the 3 other groups. There were no overlapping results of urinary normetanephrine concentrations between PC and all other groups, and only one PC dog with a plasma normetanephrine concentration in the range of the dogs with HC and NAD disease. Performances of total and free plasma variables were similar. Overlap of epinephrine and norepinephrine results between the groups was large with both urine and plasma.

Conclusion and clinical importance

Measurement of normetanephrine is the preferred biochemical test for PC and urine was superior to plasma.     

Ionic composition and osmolality of paddlefish (Polyodon spathula, Acipenseriformes) seminal fluid

Changes in ionic composition as Na⁺,K⁺, Ca²⁺ and Mg²⁺, osmolality inseminal fluid, percentage of motile spermatozoaand velocity were investigated in response toCPP and different dosage of LHRHa. The lowestvelocity of sperm was observed after use CPPtreatment. The velocity of spermatozoa,significant main effect of the treatment(P < 0.0001) and the time of sperm collection(P < 0.0104) were evaluated. The osmolality ofseminal fluid was different betweenexperimental groups of LHRHa (48.0–62.7mOsmol.kg^–1) and CPP (33.0–46.3mOsmol.kg^–1) treatments. The osmolalitywas significantly higher on the first day andone-half, then declined on day three, rangingfrom 33.0 to 62.7 mOsmol.kg^–1. Analysisof variance showed significant main effects ofthe treatment (P < 0.0001) and the time ofsperm collection (P < 0.0002) on the osmolalityof seminal fluid. The level of Na⁺ andK⁺ ion was different between experimentalgroups of LHRHa and CPP treatment. The highestconcentration of 11.11 mmol.l^–1 wasobserved at Na⁺ ion. Then theconcentrations declined on the level 1.56, 0.52and 0.36 mmol.l^–1 for K⁺, Ca²⁺and Mg²⁺ ions, respectively. There werehighly positive correlations between osmolalityof seminal fluid and dosage of LHRHa treatment(r = 0.84), velocity of spermatozoa andosmolality of seminal fluid (r = 0.57) andosmolality of seminal fluid and Na⁺concentration at seminal fluid (r = 0.70).Injection with LHRHa increased quality of spermas velocity of sperm, level of Na⁺,K⁺ and osmolality at seminal fluidcompared to CPP treatments.     

Marennine,Promising Blue Pigments from a Widespread Haslea Diatom Species Complex

In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.     

Science and conservation of Amazonian crocodilians: a historical review

1. Crocodilians represent one of the oldest extant vertebrate lineages. They have co-existed with humans throughout the Amazon basin for thousands of years, often having a strong cultural and economic influence on people's lives. Shifts in the socio-economic and political reality of the Amazon basin during the last century have led crocodilian populations to face large variations in their numbers according to different levels of exploitation and strategies for their conservation.
2. This article reviews the scientific knowledge obtained between 1945 and 2019 on the biology, conservation and management for the four Amazonian crocodilian (caiman) species (Caiman crocodilus, Melanosuchus niger, Paleosuchus palpebrosus and Paleosuchus trigonatus). It provides a general overview on past and current population status and research efforts involving caimans in the Amazon basin and discusses perspectives for the future.
3. The most significant studies on the ecology, genetics and management strategies are examined in more detail and this information is contextualized to provide an overview of the most relevant findings that might explain caiman population trends over the last 75 years.
4. Systems for sustainable management in the Amazon basin have been discussed for the past 20 years, but remain rarely applicable. It is necessary to develop new ways to maintain healthy caiman populations through innovative management programmes. Sustainable harvesting of wildlife has been shown to promote conservation targets, especially those initiatives based on community co-management. In this article, we propose some general guidelines for future management schemes, in the expectation that the information provided by the scientific community will be considered fully without political agendas determining the priorities.

     

Tyrosine hydroxylase activity and dopamine turnover of rainbow trout (Oncorhynchus mykiss) brain: the special status of the hypothalamus

The dynamics of catecholamine (CA)-synthesis enzymes have been poorly studied in fish. Tyrosine hydroxylase (TH), the rate-limiting enzyme of CA synthesis has been only studied inin vitro conditions. In the present report thein vivo CA synthesis and the CA metabolism were studied in different regions of the forebrain of the rainbow trout. Levels of norepinephrine (NE), dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and the rate of accumulation of 3,4-dihydroxyphenylalanine (DOPA) were determined by HPLC following a treatment with hydroxybenzylhydrazine (NSD), a potential inhibitor of DOPA decarboxylase. Kinetics of the accumulation of DOPA and of the decline of DOPAC were in agreement with those found in rat, evidencing that the accumulation of DOPA following NSD can be used in trout to quantify thein vivo enzymatic activity of tyrosine hydroxylase. Experiments using treatment with NSD or with methyl-p-tyrosine reached a same conclusion: the DA neuronal activity in trout is much higher than NE neuronal activity. However, the hypothalamus had high DA levelsvs. lowin vitro andin vivo TH activities and exhibited a low CA turnover.