Phosphonic analogues of morphactins. Part IV: 9-aminofluoren-9-ylphosphine oxides     

Roman Gancarz  Witold Wielkopolski  Elbieta Jaskuska  Pawel Kafarski  Barbara Lejczak  Przemyslaw Mastalerz  Jan Sylwester Wieczorek 《Pest management science》1985,16(3):234-238

9-Aminofluoren-9-ylphosphine oxides and the corresponding 9-hydroxy analogues were synthesised and evaluated for herbicidal activity using Spirodela oligorrhiza (Kurz.) Hegelm. All the test compounds were highly active at concentrations of about 10 μM and were comparable with the corresponding phosphonic esters.  相似文献   

Phosphonic analogues of morphactins. Part III: Peptides containing p-terminal 9-aminofluoren-9-ylphosphonic acid     

Barbara Lejczak  Pawel Kafarski  Roman Gancarz  Elzbieta Jaskulska  Przemyslaw Mastalerz  Jan Sylwester Wieczorek  Marta Krl 《Pest management science》1985,16(3):227-233

Peptides of 9-aminofluoren-9-ylphosphonic or 1-aminocyclohexylphosphonic acids were synthesised and found to have typical morphactin activity when tested on Lepidium sativum and Triticum vulgare. The observed effects included root elongation with simultaneous stem shortening. The results obtained indicate that these phosphonic acid derivatives of cyclohexylamine and fluoren-9-ylamine may have a similar mechanism of action.  相似文献   

Evolution and development of inflorescence architectures     

Prusinkiewicz P  Erasmus Y  Lane B  Harder LD  Coen E 《Science (New York, N.Y.)》2007,316(5830):1452-1456

To understand the constraints on biological diversity, we analyzed how selection and development interact to control the evolution of inflorescences, the branching structures that bear flowers. We show that a single developmental model accounts for the restricted range of inflorescence types observed in nature and that this model is supported by molecular genetic studies. The model predicts associations between inflorescence architecture, climate, and life history, which we validated empirically. Paths, or evolutionary wormholes, link different architectures in a multidimensional fitness space, but the rate of evolution along these paths is constrained by genetic and environmental factors, which explains why some evolutionary transitions are rare between closely related plant taxa.  相似文献   

Identification,ecological evaluation and phylogenetic analysis of non‐symbiotic endophytic fungi colonizing timothy grass and perennial ryegrass grown in adjacent plots     

Sebastian Wojciech Przemieniecki  Marta Damszel  Tomasz Pawe&#x; Kurowski  J&#x;drzej Mastalerz  Karol Kotlarz 《Grass and Forage Science》2019,74(1):42-52

Non‐systemic endophytes coexist with grasses and produce positive or negative effects for the host. In agricultural grasses, endophytes such as Epichloë spp. (formerly: Neotyphodium spp.) enhance the biometric parameters and agricultural value of grass biomass and seeds. Some endophytic fungi produce active substances that exert a negative influence on grass‐fed livestock. There is a general scarcity of studies investigating other endophytic fungi, the species composition of fungal communities, fungal species capable of colonizing different grasses and endophyte transfer between grass taxa. This study aims to fill in the existing knowledge gap by describing the relationships between fungal species and grass species. Timothy grass (Phleum pratense L.) is more readily colonized by endophytic fungi than perennial ryegrass (Lolium perenne L.), and the ratio of fungi isolated from the above species was determined at 3:1. Ecological indicators, especially diversity, were also higher in the fungal community colonizing timothy grass. The vast majority of the isolated fungi were ascomycetes. In addition, two Basidiomycota isolates and three Oomycota isolates (Phythium acanthicum) were also obtained from timothy grass. The most prevalent fungal species were Alternaria alternata, Microdochium bolleyi and Epicoccum nigrum. An analysis of minisatellite DNA regions revealed high levels of genetic polymorphism in A. alternata, whereas the remaining isolates were characterized by low levels of genetic variation or genetic homogeneity. The transfer of endophytic fungi between grass species was determined, which was one of the most important observations made in the study. The Sørensen–Dice coefficient reached 50%, which indicates that all fungal species isolated from perennial ryegrass are capable of colonizing timothy grass.  相似文献   

Probiotics and Prebiotics     

Przemyslaw Jan Tomasik  Piotr Tomasik 《Cereal Chemistry》2003,80(2):113-117

Probiotics, bacteria from the genera Bifidobacterium and Lactobacillus, and yeast, Saccharomyces, as well as prebiotics belonging to the group of dietary fiber (inulin with low degree of polymerization, fructose‐derived oligosaccharides, and resistant starch) are natural factors useful in prophylaxis and therapy of several common diseases including some types of cancer. They are available commercially and can be introduced to produce so‐called functional food. Probiotics and prebiotics can be utilized either separately or jointly (as synbiotics or eubiotics). Mechanisms of both biotics are discussed. The role of cereals in probiosis is considered. Possibilities for extension of the uses of the original Chinese probiotic, chaw tofu, are also considered.  相似文献   

Generation of spatial patterns through cell polarity switching     

Robinson S  Barbier de Reuille P  Chan J  Bergmann D  Prusinkiewicz P  Coen E 《Science (New York, N.Y.)》2011,333(6048):1436-1440

  相似文献   

Phosphonic analogues of morphactins. Part V: Peptides containing 9-aminofluoren-9-ylphosphine oxides     

Pawel Kafarski  Barbara Lejczak  Roman Gancarz  Elbieta Jaskulska  Przemyslaw Mastalerz  Jan Sylwester Wieczorek  Iwona Zbyryt 《Pest management science》1985,16(3):239-243

Di- and tripeptides containing P-terminal 9-aminofluoren-9-ylphosphine oxides were synthesised and evaluated for herbicidal activity using Spirodela oligorriza (Kurz.) Hegelm. The glycylglycyl and threonyl peptides showed high activity as measured by the reduction of dry matter.  相似文献   

Simultaneous Use of Trace Metals, 210Pb and 137Cs in Floodplain Sediments of a Lowland River as Indicators of Anthropogenic Impacts     

Edyta Łokas  Przemyslaw Wachniew  Dariusz Ciszewski  Piotr Owczarek  Nguyen Dinh Chau 《Water, air, and soil pollution》2010,207(1-4):57-71

This study focuses on the distribution of selected trace metals, ¹³⁷Cs and ²¹⁰Pb, in floodplain deposits of the lowland Warta River (southern Poland) downstream of Cz?stochowa, a large city with an iron smelter. The depth profiles of trace metal (Zn, Pb, Cu, Ni, Cd and Mn), ²¹⁰Pb and ¹³⁷Cs contents in floodplain sediments were used to derive deposition rates on the floodplain for the twentieth century. The applicability of particular chronometric tools is considered within the context of their mutual relationships and confirmed by the consistency of the results. Deposition rate estimates for the past 50 years based on the vertical patterns of trace metal concentrations, which were correlated with particular events in the development of the smelter, range from 0.4 cm·year^?1 in profiles situated in backswamps far from the channel to over 1.1 cm·year^?1 in profiles of the natural levee adjacent to the river. Deposition rates based on ²¹⁰Pb inventories in the profiles range from 0.08 to 0.66 g·cm^?2·year^?1, which corresponds to linear sedimentation rates of 0.10 to 0.91 cm·year^?1, respectively. Dating of characteristic levels associated with peak fallout of ¹³⁷Cs gives sediment accretion rates resembling those obtained from trace metals and ²¹⁰Pb. The period of the highest sediment accumulation rate could be related to the highest loads of effluent from the iron smelter and city of Cz?stochowa, which were substantially reduced after the construction of effluent treatment plant.  相似文献   

Genome expansion and gene loss in powdery mildew fungi reveal tradeoffs in extreme parasitism     

Spanu PD  Abbott JC  Amselem J  Burgis TA  Soanes DM  Stüber K  Ver Loren van Themaat E  Brown JK  Butcher SA  Gurr SJ  Lebrun MH  Ridout CJ  Schulze-Lefert P  Talbot NJ  Ahmadinejad N  Ametz C  Barton GR  Benjdia M  Bidzinski P  Bindschedler LV  Both M  Brewer MT  Cadle-Davidson L  Cadle-Davidson MM  Collemare J  Cramer R  Frenkel O  Godfrey D  Harriman J  Hoede C  King BC  Klages S  Kleemann J  Knoll D  Koti PS  Kreplak J  López-Ruiz FJ  Lu X  Maekawa T  Mahanil S  Micali C  Milgroom MG  Montana G  Noir S  O'Connell RJ  Oberhaensli S 《Science (New York, N.Y.)》2010,330(6010):1543-1546

Powdery mildews are phytopathogens whose growth and reproduction are entirely dependent on living plant cells. The molecular basis of this life-style, obligate biotrophy, remains unknown. We present the genome analysis of barley powdery mildew, Blumeria graminis f.sp. hordei (Blumeria), as well as a comparison with the analysis of two powdery mildews pathogenic on dicotyledonous plants. These genomes display massive retrotransposon proliferation, genome-size expansion, and gene losses. The missing genes encode enzymes of primary and secondary metabolism, carbohydrate-active enzymes, and transporters, probably reflecting their redundancy in an exclusively biotrophic life-style. Among the 248 candidate effectors of pathogenesis identified in the Blumeria genome, very few (less than 10) define a core set conserved in all three mildews, suggesting that most effectors represent species-specific adaptations.  相似文献