GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands

GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board

Trifolium mutabile as New Species of Annual Legume for Mediterranean Climate Zone: First Evidences on Forage Biomass, Nitrogen Fixation and Nutritional Characteristics of Different Accessions

The present study evaluated the forage production, nitrogen fixation and the qualitative characteristics of different accessions of Trifolium mutabile, a new species of annual clover, collected in southern Italy. Forage traits were assessed by harvesting plants at the vegetative stage (stem elongation) and the subsequent regrowth at the flowering stage (inflorescence emergence-main shoot). From results, significant differences were found among the accessions of T. mutabile in terms of forage biomass production (from 5.1 to 8.2 t ha−1 dry matter), capacity of nitrogen fixation (58.2–76.8% Ndfa) and forage nutritional characteristics. Besides the high forage yield, the investigated accessions showed favourable values of production and quality, representing also worthy germplasm for selection programs as well as the application for possible plant cultivar registration. Moreover, it is interesting to underline that T. mutabile may represent a valuable alternative to commonly cultivated annual clover species due to its prolonged vegetative cycle. However, further investigations are needed to assess the self-reseeding capacity of T. mutabile when utilized as pasture species

Natural compounds with herbicidal activity

Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints

Performance of warm-season turfgrasses under different water regimes in the Mediterranean climate conditions of Southern Italy

In Mediterranean areas, very scarce rainfalls during the summer season are a limiting factor to the sowing and managing of turfgrasses. This work evaluates the response to different irrigation regimes (50 or 75% of reference evapotranspiration) of Cynodon dactylon (L.) Pers. cv Transcontinental, Paspalum vaginatum Swartz cv Salam, Pennisetum clandestinum (Chiov.) Hochst. cv AZ1, Stenotaphrum secundatum (Walt.) Kuntze cv Palmetto and Zoysia japonica Steud. cv El Toro. Performance of turfgrasses was evaluated in term of turf quality, colour index and ground cover. Only when rainfalls were scarce, water regime restoring the 75% of the evapotranspiration (ETo) showed significant effects. Under rainy conditions, the restoration of only the 50% of ETo was able to give highly acceptable values. The best performance was observed for Z. japonica, C. dactylon and P. vaginatum, whereas P. clandestinum and S. secundatum showed lower adaptability to water stress

Effects of Some Environmental Factors on Seed Germination and Spreading Potentials of Silybum marianum Gaertner

Silybum marianum Gaertner is spreading in many crops of Southern Italy, particularly in durum wheat, sugar beet and some vegetable crops. Information about its biology are useful to set up effective control strategies. Four experiments were carried out at the Crop Science Department of the University of Bari (Southern Italy). Two trials were conducted in Petri dishes and evaluated the effects of different light, temperature and osmotic stress conditions on the seed germination. Another trial evaluated the ability of seedlings to emerge from different depths. The effects of eight different sowing periods on the plant growth were assessed in the fourth experiment. The highest germination rate was found with constant temperatures of 25 °C or 30 °C and with alternating temperatures of 25- 15 °C for 8 and 16 hours respectively. Germination was affected by the light and was significantly decreased at 0.2 Mpa and completely inhibited at -0.8 Mpa. Plant emergence was strongly reduced from a depth of more than 3 cm. The plant size at the first bloom was reduced by postponing the sowing period from October to February. The same decreasing trend was observed in the number of flower heads and in the number of days required for the first bloom. Results can suggest some important strategies to manage this species. False sowing, followed by irrigation, can be recommended in summer, in order to obtain the highest seed germination. Since the emergence of this plant is very scarce from a depth of more than 3 cm, ploughing can be effective to bury seeds in case of strong disseminations in order to reduce the infestation in the following crop

Effects of Some Environmental Factors on Seed Germination and Spreading Potentials of Silybum marianum Gaertner

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Weeds in Non-Agricultural Areas: How to Evaluate the Impact? A Preliminary Case Study in Archaeological Sites

The term “weeds” refers to “plants suitable for habitats modified by man and that interfere with human activities”. It implies an anthropocentric rather than an ecological vision since the existence and the characteristic of the interference depends on men’s purposes. In the archaeological sites, the most important damage is the functional one and it ranges from hazards for the structures to the interference that weed flora can exert on the technical management and fruition of the site. In this particular type of environment, the diverse methods available to quantify the magnitude of the infestation are not sufficient to describe the potential or actual hazard to which a given infested site is subjected. Therefore, it is necessary to consider a greater degree of detail (including morphological, ecological, and physiological properties of the weeds) and to keep them all in consideration. The aim of the present work was to try to identify and propose a method for the assessment of the hazards and thus the damages that a weed community can lead in sites of historical and archaeological interest. The procedure quantifies the degree of the infestation, in terms of occurring species, quantifies the related hazard based on some traits of the weed species, and calculates indexes capable of providing synthetic and comparable information on the hazard to which the site is exposed. The proposed method was applied and tested in some sites of archaeological interest in the Apulia Region, in southern Italy. Applied to the surveyed archaeological sites, the proposed Indexes revealed the presence of weed infestations variously assorted in terms of potential damage, generating different hazard scores. This confirms the importance of understanding the type of infestation and not only its extent. In this study, a procedure was provided that can support decision-makers. Although studied for archaeological sites, the same principles adopted in this procedure could be proposed for other non-agricultural areas

Living Mulch with Subterranean Clover (<i>Trifolium subterraneum</i> L.) Is Effective for a Sustainable Weed Management in Globe Artichoke as Annual Cropping in Puglia (Southern Italy)

Italy represents the world leading producer of globe artichoke, and Puglia (Southern Italy) supplies about one-third of the nation’s production. In this research, the influence of mulching (both living mulch with subterranean clover and biodegradable mulch film) on both weed infestation and globe artichoke yield in comparison with conventional tillage was evaluated. Two globe artichoke genotypes (Capriccio—hybrid cultivar—and Brindisino—sanitized local variety) were tested in an open field located in Puglia. The following parameters were evaluated: weed infestation, yield and canopy of globe artichoke, and biomass and canopy of subterranean clover. Yield of globe artichoke (on average 16 buds plant−1) was not influenced by soil management although the total weed cover was lower by using conventional tillage. Mean canopy of T. subterraneum was higher under Brindisino (about 65%) in comparison with Capriccio (about 45%). Dry weight was higher in Brindisino (about 12 g m−2) than Capriccio (about 6 m−2) without differences among soil management treatments. Subterranean clover showed a good ability to control weed cover especially under Brindisino genotype (weed infestation always less than 1%) highlighting its particularly suitability for local varieties of globe artichoke instead of hybrid cultivars (weed infestation up to 5%). In conclusion, the results of this study suggest the positive effects of living mulch with subterranean clover for a sustainable weed management in globe artichoke as annual cropping in Puglia

Oregano and its potential use as a bioherbicide

Widespread use of synthetic herbicides in weed control could result in negative impact on human health and on the environment. Natural compounds could be successfully used as bioherbicides because they are potentially more environmental friendly and safe. Plants are an important source of active compounds. In particular, many species belonging to the Labiate family produce essential oils containing compounds that could act as natural herbicides. In this paper we report on preliminary studies about the effects on seed germination and plant growth of an oregano hybrid (Origanum vulgare L. ssp. virilidum × O. vulgare L. ssp. hirtum (Link) Iestwart). Experiments were done both in pots and in the field. Increasing amounts of chopped leaves and stems of oregano were added to the soil. In the pots, several weed species were sown, whereas naturally occurring infestation was evaluated in the field. In comparison with the control, a reduced number of weeds was observed where oregano biomass was added. The above-mentioned trend was more visible in the pots than in the field. The results suggest that the hybrid of oregano used in the trial could be an interesting source of natural compounds effective against weeds. Hence, further studies with this plant are likely to be successful