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91.
Due to an increasing demand of forestry products, nitrogen (N) fertilization of coniferous forests may in the future become a standard silvicultural practice in parts of the boreal region that is not too remotely situated. Beside positive effects on productivity, forest fertilization may induce changes in species composition of the ground vegetation. More information on the magnitude of such side effects is needed to evaluate whether commercial forest fertilization is in accordance with principles of sustainable forestry and preservation of biodiversity. 相似文献
92.
ABSTRACT: Antimicrobial peptides play a pivotal role as key effectors of the innate immune system in plants and animals and act as endogenous antibiotics. The molecules exhibit an antimicrobial activity against bacteria, viruses, and eukaryotic pathogens with different specificities and potencies depending on the structure and amino-acid composition of the peptides. Several antimicrobial peptides were comprehensively investigated in the last three decades and some molecules with remarkable antimicrobial properties have reached the third phase of clinical studies. Next to the peptides themselves, numerous organisms were examined and analyzed regarding their repertoire of antimicrobial peptides revealing a huge number of candidates with potencies and properties for future medical applications. One of these organisms is the horse, which possesses numerous peptides that are interesting candidates for therapeutical applications in veterinary medicine. Here we summarize investigations and knowledge on equine antimicrobial peptides, point to interesting candidates, and discuss prospects for therapeutical applications. 相似文献
93.
Melony J. Sellars Louise Franz Ralf Joachim Moser 《Journal of the World Aquaculture Society》2023,54(1):167-180
Novel Decapod Iridescent virus (DIV1) infections emerged in mainland China around 2014 and have devastated shrimp aquaculture operations in Chinese coastal provinces. In 2020, DIV1 has spread to Taiwan with devastating results to shrimp and crayfish farms, in addition to being found in wild caught Penaeus monodon from the Indian Ocean. This trend is a major cause for concern and an urgent reminder to expand the tools needed to monitor the spread of DIV1 globally. Here, we describe a set of four different real-time polymerase chain reaction (PCR) assays positioned across the genome of DIV1 to detect the virus in shrimp tissues. All four assays show a wide dynamic range and high analytical sensitivity and specificity. In addition, the newly developed assays show excellent diagnostic sensitivity and specificity in clinical Litopenaeus vannamei samples of North Asian origin. The new molecular toolset will enhance global capabilities to monitor the spread of DIV1 and ultimately be used as an early warning system for farmers and authorities to engage in appropriate risk mitigation strategies. 相似文献
94.
Klaus G. Tietjen Joachim F. Kluth Roland Andree Michael Haug Markus Lindig Klaus H. Müller Heinz J. Wroblowsky Achim Trebst 《Pest management science》1991,31(1):65-72
The QB binding niche of photosystem II is also the binding site for many different herbicides. In order to understand the mode of binding of the herbicides, a 3-dimensional model of the binding niche was constructed. The model was based upon a comparison of the known structure of the QB binding niche in purple bacteria with sequence and mutant data of the D-1 protein of photosystem II. Plastoquinone builds up hydrogen bonds to phenylalanine 265 backbone amide nitrogen, to serine 264 hydroxyl, and to histidine 215 delta-1 nitrogen. In addition to these hydrogen bond donors and acceptors, herbicides can build up hydrogen bonds to backbone carbonyl of alamine 263 and to serine 268 hydroxyl. This is supported by binding data of inhibitors in Chlamydomonas reinhardtii chloroplasts of wild type and of five D-1 protein mutants (Ser264 Ala, Ala251 Val, Phe255Tyr, Val2191le, Leu275Phe). 相似文献
95.
Hans Joachim Telle 《Journal of pest science》1966,39(5):67-69
Summary When pesticides are used safety measures are necessary. Laws alone are insufficient when their application is not controlled. Above all it is to be expected that people will not be endangered by ignorant use of pesticides. Many fields of pest control, i.e. the control of cockroaches, are not sufficiently developed in Germany. In the near future the control of hygienic and other pests should be intensified. Therefore we need well-trained specialists, and only these should be permitted to control pests in household and field. 相似文献
96.
97.
Dr. Joachim Reisch 《Journal of pest science》1961,34(8):113-117
V. Zusammenfassung Im vorliegenden wurde versucht, einen kurzen Überblick über die derzeit wichtigsten forstpathologischen Problemen in Kenya zu vermitteln. Wenn auch die Termiten bei weitem alle anderen Schädlinge bisher überschatten, so werden die neu angelegten, noch relativ jungen Wirtschaftswaldrungen vor allem aus fremdländischen Holzarten von einem sehr großen Reservoir tropischer Krankheitserreger in zunehmendem Maße bedroht. Hierbei handelt es sich um Lepidopteren, Coleopteren und zahlreiche Schadpilze. Natürlich darf dieser Bericht keinesfalls als vollständig angesehen werden, dazu war die Zeit viel zu knapp bemessen. 相似文献
98.
Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides LC can be combined into one taxon on the basis of several contributions on both DNA sequence and protein analyses reported in the literature. Moreover, for the differentiation and identification of mycoplasmas of the "mycoides cluster", we investigated the rpoB gene, encoding the beta-subunit of the RNA polymerase. A segment of 527 bp of the rpoB gene was amplified from 31 strains of ruminant mycoplasmas by PCR. The nucleotide sequences were determined and aligned, and accurate genetic relationships were calculated. Cluster analysis of rpoB DNA allowed species differentiation within the "mycoides cluster" and confirmed that M. mycoides subsp. capri and M. mycoides subsp. mycoides LC cannot be distinguished from each other. "Mycoplasma mycoides subsp. capri" is proposed as a common name for both subspecies. 相似文献
99.
Nikolas von Lüpke Jan Hansen Joachim Saborowski 《European Journal of Forest Research》2012,131(6):1979-1990
For a current inventory using double sampling for stratification with a reduced second-phase sample size, compared with a previous inventory, we develop a three-phase sampling procedure that exploits plot data from the previous inventory or their updates based on a growth model to increase precision. The three-phase procedure combines double sampling for stratification with a two-phase regression estimator within strata. We consider sampling from an infinite population in the first phase. The combined estimator is tested in a case study using data from two consecutive inventories in four State Forest Districts in Lower Saxony, Germany. Data from a reduced number of sample plots from the second occasion are combined with (1) volumes from the first occasion or (2) growth simulations on the sample plots from the first occasion. The data from the previous inventory or their updates serve as the auxiliary variable for the regression estimator of the strata means of the target variable. This case study indicates a remarkable increase in precision and thereby an enormous cost-saving potential for reduced intermediate inventories in a periodic inventory design with both types of auxiliary variables. 相似文献
100.
In managed forests, the occurrence of deadwood (DW) can be regarded as a stochastically rare event with strong clumping and high local variability (Meyer in Forstwissenschaftliches Centralblatt 118:167–180, 1999). Traditional sampling techniques, such as Fixed Area Sampling, Angle Count Sampling and Line Intersect Sampling, do not regard this fact and may be inefficient for surveys of DW, because of limited search areas. A sampling technique that should remedy this shortcoming is Point Transect Sampling (Buckland et?al. in Introduction to distance sampling: estimating abundance of biological populations. Oxford University Press, Oxford, 2001; Advanced distance sampling: estimating abundance of biological populations. Oxford University Press, Oxford, 2004), where as a matter of principle, all objects that are sighted from a fixed location are counted. We compare Point Transect Sampling with the other well-established sampling approaches for the estimation of volume, necromass and carbon storage in terms of precision and sampling effort. It is shown that Point Transect Sampling is the superior method for sampling standing DW regarding efficiency, whereas for sampling downed DW, it is clearly outperformed by Line Intersect Sampling. 相似文献