Search results for "Otan"
showing 10 items of 6391 documents
Genetic basis of trichome production in Arabidopsis lyrata.
2002
Leaf trichomes may protect plants against herbivorous insects, and may increase tolerance to drought and UV-radiation. The perennial herb Arabidopsis lyrata (Brassicaceae) is polymorphic for trichome production and occurs in a glabrous and trichome-producing form. In addition, there is quantitative variation in trichome density among trichome-producing plants. To examine the genetic basis of glabrousness, we conducted controlled crosses with plants originating from two natural populations in Sweden (one polymorphic for trichome-production, and one consisting of glabrous plants only). In addition, we estimated the heritability of trichome number from parent-offspring regressions for plants o…
Cytosporones, coumarins, and an alkaloid from the endophytic fungus Pestalotiopsis sp. isolated from the Chinese mangrove plant Rhizophora mucronata
2009
Chemical examination of the endophytic fungus Pestalotiopsis sp., isolated from the leaves of the Chinese mangrove Rhizophora mucronata, yielded 11 new compounds including cytosporones J-N (1-3, 5-6), five new coumarins pestalasins A-E (8-12), and a new alkaloid named pestalotiopsoid A (14), along with the known compounds cytosporone C (4), dothiorelone B (7), and 3-hydroxymethyl-6,8-dimethoxycoumarin (13). The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic data analysis.
Iron operates as an important factor promoting year-round diazotrophic cyanobacteria blooms in eutrophic reservoirs in the tropics
2021
Abstract We hypothesize that iron availability plays an important role in driving phytoplankton structure and dynamics in tropical reservoir. This role has often been neglected in routine monitoring of water quality since the main focus has been addressed on macronutrients such phosphorus and nitrogen. To elucidate the potential regulation exerted by iron availability on phytoplankton, a limnological investigation was carried out in two neighboring eutrophic reservoirs in tropical China. Traditional physical and chemical variables were measured along with total and dissolved iron concentrations to explore how they could influence phytoplankton structure. Statistical analyses showed that dis…
Nutrient removal by rice–wheat cropping system as influenced by crop establishment techniques and fertilization options in conjunction with microbial…
2020
AbstractNutrient uptake by the rice–wheat cropping system (RWCS) is an important indicator of soil fertility and plant nutrient status. The hypothesis of this investigation was that the rate and sources of nutrient application can differentially influence nutrient removal and soil nutrient status in different crop establishment techniques (CETs). Cropping system yield was on par in all the CETs evaluated, however, there were significant changes in soil nutrient availability and microbiological aspects. The system nitrogen (N), phosphorus (P), potassium (K) and zinc (Zn) uptake in aerobic rice system followed by zero tillage wheat (ARS-ZTW) was 15.7–17.6 kg ha−1, 0.7–0.9 kg ha−1, 7–9.8 kg ha…
Differential toxicity of simazine and diuron to Torilis arvensis and Lolium rigidum
1990
Summary: In a soil application, Torilis arvensis was nearly as susceptible as Lolium rigidum to simazine but was 18-fold more tolerant to diuron. Treat ment with diuron inhibited photosynthesis in L. rigidum but had only a limited effect in T. arvensis although chloroplasts isolated from both species displayed similar susceptibility. 14C-diuron degradation in plants was limited, with the formation of conjugates of mono-methyl-diuron in T. arvensis and N-dealkylated derivatives of diuron in L. rigidum. 14C-diuron entered the roots and was translocated throughout the leaves of L. rigidum but was restricted to stems, leaf petioles and leaf veins of T. arvensis. This difference in transport pat…
Allium albanicum (Amaryllidaceae), a new species from Balkans and its relationships with A. meteoricum Heldr. & Hausskn. ex Halácsy
2019
A new species, Alliumalbanicum, is described and illustrated from Albania (Balkan Peninsula). It grows on serpentines or limestone in open rocky stands with a scattered distribution, mainly in mountain locations. Previously, the populations of this geophyte were attributed to A.meteoricum Heldr. & Hausskn. ex Halácsy, described from a few localities of North and Central Greece. These two species indeed show close relationships, chiefly regarding some features of the spathe valves, inflorescence and floral parts. They also share the same diploid chromosome number 2n =16 and similar karyotype, while seed testa micro-sculptures and leaf anatomy reveal remarkable differences. There are …
Diversity and Evolution of the Phenazine Biosynthesis Pathway
2010
ABSTRACT Phenazines are versatile secondary metabolites of bacterial origin that function in biological control of plant pathogens and contribute to the ecological fitness and pathogenicity of the producing strains. In this study, we employed a collection of 94 strains having various geographic, environmental, and clinical origins to study the distribution and evolution of phenazine genes in members of the genera Pseudomonas , Burkholderia , Pectobacterium , Brevibacterium , and Streptomyces . Our results confirmed the diversity of phenazine producers and revealed that most of them appear to be soil-dwelling and/or plant-associated species. Genome analyses and comparisons of phylogenies inf…
How Do Software Companies Deal with Artificial Intelligence Ethics? : A Gap Analysis
2022
The public and academic discussion on Artificial Intelligence (AI) ethics is accelerating and the general public is becoming more aware AI ethics issues such as data privacy in these systems. To guide ethical development of AI systems, governmental and institutional actors, as well as companies, have drafted various guidelines for ethical AI. Though these guidelines are becoming increasingly common, they have been criticized for a lack of impact on industrial practice. There seems to be a gap between research and practice in the area, though its exact nature remains unknown. In this paper, we present a gap analysis of the current state of the art by comparing practices of 39 companies that …
Distribution, ecology and conservation status of Dionysia involucrata Zaprjag., an endangered endemic of Hissar Mts (Tajikistan, Middle Asia)
2014
<em>Dionysia involucrata</em> Zaprjag. (Primulaceae) is known as critically endangered endemic species of Hissar Mountains in Tajikistan. It is reported from few localities mainly in Varzob River valley and its tributaries. The species inhabits steep or overhanging faces of granite rocks in narrow river gorges. During the research all known populations of <em>D. involucrata</em> were examined in respect of the habitat conditions and species composition of vegetation plots. We analyzed the population extent of the species in its range in Tajikistan and the main threats in order to assess its conservation status. The detrended correspondence analysis was performed on a…
Intraspecific Differences in Spectral Reflectance Curves as Indicators of Reduced Vitality in High-Arctic Plants
2017
Remote sensing is a suitable candidate for monitoring rapid changes in Polar regions, offering high-resolution spectral, spatial and radiometric data. This paper focuses on the spectral properties of dominant plant species acquired during the first week of August 2015. Twenty-eight plots were selected, which could easily be identified in the field as well as on RapidEye satellite imagery. Spectral measurements of individual species were acquired, and heavy metal contamination stress factors were measured contemporaneously. As a result, a unique spectral library of dominant plant species, heavy metal concentrations and damage ratios were achieved with an indication that species-specific chan…