14 research outputs found
Allelopathic Potential of Invasive Plantago virginica on Four Lawn Species
Plantago virginica L. has invaded many lawn ecosystems in the Eastern part of China. The invasion has incurred an economic cost to remove them. In order to prevent the invasion, it is critical to understand the invasive mechanisms of this species. However, few studies have been conducted on the allelopathic mechanisms of its invasion. In this study, we examined allelopathic effects of P. virginica on germination of seeds and growth of seedlings of four widely used lawn species. We found extensive allelopathic potential of P. virginica on other lawn species, which varied with species and developmental stage. While most effects of the extracts of P. virginica were inhibitory, some variables in some species were promoted by the addition of the extracts. The extracts of P. virginica significantly inhibited seed germination of Agrostis matsumurae. While the overall differences in seed germination rate of Poa annua were significant among treatments, difference between control and any of the treatments was not significant. The height of seedlings of A. matsumurae and Cynodon dactylon was significantly lower under the treatments of adding extracts of P. virginica. In contrast, growth of seedlings of Festuca elata and P. annua did not show significant differences among treatments. The root length of A. matsumurae, C. dactylon and P. annua was suppressed by the extracts of P. virginica whereas root length of F. elata was not affected. Aboveground biomass of A. matsumurae and F. elata was significantly higher than control, except for F. elata at the concentration of 50mg/mL, whereas aboveground biomass of C. dactylon and P. annua was reduced at higher concentrations of the extracts. Except for A. matsumurae, root biomass of the other three lawn species declined under the treatments with the extracts of P. virginica. Our results revealed that P. virginica had allelopathic potential on four lawn species and supported the theory of “novel weapons hypothesis”. Invasion by P. virginica in lawn can be moderated by selecting those species that are not affected or promotionally affected by it.Yeshttp://www.plosone.org/static/editorial#pee
Tibetan Medicine: A Systematic Review of the Clinical Research Available in the West
Background. Little is known about Tibetan medicine (TM), in Western industrialized countries. Objectives. To provide a systematic review of the clinical studies on TM available in the West. Data Sources. Seven literature databases, published literature lists, citation tracking, and contacts to experts and institutions. Study Eligibility Criteria. Studies in English, German, French, or Spanish presenting clinical trial results. Participants. All patients of the included studies. Interventions. Tibetan medicine treatment. Study Appraisal and Synthesis Methods. Included studies were described quantitatively; their quality was assessed with the DIMDI HTA checklist; for RCTs the Jadad score was used. Results. 40 studies from 39 publications were included. They were very heterogeneous regarding study type and size, treated conditions, treatments, measured outcomes, and quality. Limitations. No Russian, Tibetan, or Chinese publications were included. Possible publication bias. Conclusions. The number of clinical trials on TM available in the West is small; methods and results are heterogeneous. Implications of Key Findings. Higher quality larger trials are needed, as is a general overview of traditional usage to inform future clinical trials. Systematic Review Registration Number. None
Physiological and biochemical parameters: new tools to screen barley root exudates allelopathic potential (*Hordeum vulgare* L. subsp. *vulgare*
peer reviewedMorphological markers/traits are often used in the detection of allelopathic stress, but optical signals including chlorophyll a fluorescence emission could be useful in developing new screening techniques. In this context, the allelopathic effect of barley (Hordeum vulgare subsp. vulgare) root exudates (three modern varieties and three landraces) were assessed on the morphological (root and shoot length, biomass accumulation), physiological (Fv/Fm and F0), and biochemical (chlorophyll and protein contents) variables of great brome (Bromus diandrus Roth., syn. Bromus rigidus Roth. subsp. gussonii Parl.). All the measured traits were affected when great brome was grown in a soil substrate in which barley plants had previously developed for 30 days before being removed. The response of receiver plants was affected by treatment with activated
charcoal, dependent on barley genotype and on the nature of the growing substrate. The inhibitory effect was lower with the addition of the activated charcoal suggesting the release of putative allelochemicals from barley roots into the soil. The barley landraces were more toxic than modern varieties and their effect was more pronounced in sandy substrate than in silty
clay sand substrate. In our investigation, the chlorophyll content and Fv/Fm were the most correlated variables with barley allelopathic potential. These two parameters might be considered as effective tools to quantify susceptibility to allelochemical inhibitors in higher plants