Festuca rubra L. Origin and diffusion. Introduction. Description

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1 Festuca rubra L. Origin and diffusion Origin: Europe Distribution: widely distributed in the arctic and temperate zones of Asia, Europe, and North America Invasive potential: medium Source: buckeyeturf.osu.edu Photo: Trevor J. Source calfloranursery.com Source:naturespot.org.uk Introduction F. rubra is a perennial cool season grass, found worldwide. It is best adapted to well-drained soils in cool, temperate climates; used as turf for lawns, it is often planted for its shade tolerance. Red fescue is an excellent soil stabilizer, used for stabilizing waterways and slopes. F. rubra species is a morphologically diverse outcrossing complex, containing distinct ecotypes occupying a wide array of habitats. This species can evolve tolerance to several abiotic stress, such as atmospheric pollutant or heavy-metals in soil, forming specific resistant ecotypes Common names: Red fescue (English name), festuca rossa (italian name) Description Life-form and periodicity: perennial grass Height: cm Roots habit: The creeping root system, it is able to develop in shallow soil. Maximum root depth: 30 cm. Culm/Stem/Trunk: stems are usually bent at the reddish or purplish base and then erected. Smooth or slightly scabrous only in the top.

2 Fam. Poaceae Description Leaf: the leaves are narrow, needle like, wiry and bright green. They are pressed together in a V shape and appear nearly round. Rate of transpiration: 4,5 8,5 mm/day Reproductive structure: The inflorescence is a narrow panicle. There are 4 to 10 spikelet flowers, which are up to 15 mm long Propagative structure: the fruit is a caryopsis. Development Sexual propagation: by seed. The pollination is anemophilous and the time that elapses between the pollination and seed harvest is days. Slow seed spread rate. Asexual propagation: it spreads primarily by rhizomes, especially in dense herbaceous formations where the germination of a seed is prevented by the pressure of the adult species. Rapid vegetative spread rate. Growth rate: moderate Habitat characteristics Light and water requirement: partial shading conditions and medium-high water requirement. Soil requirements: it is adapted to fine and medium soil textures and at moderately nutrient-poor soils. Tolerance/sensitivity: it is shade tolerant. It tolerates soils low in fertility, acid to slightly alkaline soils (ph ) and flooding and poorly drained sites. It is somewhat tolerant of salt spray..

3 Phytotechnologies applications Red fescue is useful in phytoremediation of soils contaminated by industrial activities such as mining, energy, and fuel production. As metal-tolerant plant, it is frequently utilized to establish vegetative cover in mine spoil heaps for phytostabilisation (Wong et al., 1994; Simon, 2005; Padmavathiamma and Li, 2009). Metals are mainly accumulated in roots, limiting the potential contaminant assimilation by grazers and herbivorous insects (Simon, 2005). This species can evolve tolerance to a wide array of abiotic stress, such as atmospheric pollutant or heavy-metals in soil, forming specific resistant ecotypes. Experimental studies -Experiment 1- Reference Contaminants of concern Mechanism involved in phytoremediation: Phytostabilisation/rhizodegradation/phyt oaccumulation/phytodegradation/phytov olatilization/ hydraulic control/ tolerant Types of microorganisms associated with the plant Requirements for phytoremediation (specific nutrients, addition of oxygen) Substrate characteristics Laboratory/field experiment Age of plant at 1st exposure (seed, post-germination, mature) Length of experiment Initial contaminant concentration of the substrate G. Adam and H.J. Duncan, Effect of diesel fuel on growth of selected plant species. Env. Geochemistry and Health 21: Diesel oil, a complex mixture of hydrocarbons Rhizodegradation Seed The germination rates were measured 14 days after planting Plant were exposed to varying concentration of diesel oil: 0 g/kg, 25 g/kg, 50 g/kg

4 Phytotechnologies applications Post-experiment contaminant concentration of the substrate Post-experiment plant condition Contaminant storage sites in the plant and contaminant concentrations in tissues (root, shoot, leaves, no storage) Germination rates of F. rubra ssp. rubra exposed to 0, 25 and 50 g/kg of diesel oil were 82%, 88%, 40%, respectively. The overall heights of plants grown in diesel oil contaminated soil were stunted compared to control plants grown in uncontaminated soil. Plants grown in diesel oil contaminated soil exhibit formation of adventitious roots (root structures which arise in unusual positions) plant roots avoid diesel oil contaminated areas completely if they have uncontaminated soil to grow into. If there is no available uncontaminated soil, roots will grow through contaminated regions until they find an area of uncontaminated soil. No storage -Experiment 2- Reference Contaminants of concern Mechanism involved in phytoremediation: Phytostabilisation/rhizodegradation/phyt oaccumulation/phytodegradation/phytov olatilization/ hydraulic control/ tolerant Types of microorganisms associated with the plant Simon L., Stabilization of metals in acidic mine spoil with amendments and red fescue (Festuca rubra L.) growth. Environmental Geochemistry and Health, 27(4), Cd, Cu, Pb, Zn Phytostabilisation

5 Phytotechnologies application Requirements for phytoremediation (specific nutrients, addition of oxygen) Substrate characteristics Laboratory/field experiment Age of plant at 1st exposure (seed, post-germination, mature) Length of experiment 40 mg kg-1 nitrogen were added to make soil suitable for plant growth. Treatments: 1. 1) 0,5% CaCO3 (liming agent to raise soil ph for plant growth) 2) 1 + 5% municipial sewage sludge compost (for metal stabilisation) 3) 1 + 5% peat (for metal stabilisation) 4. 4) 1 + 7,5% zeolite (for metal immobilization) 5. 5) 1 + 0,5% KH2PO4 (for trace metals sorption and/or co-precipitating) 6) (combined treatment). All amendments influenced positively the dry matter yield (biomass production) of red fescue, but application of 0.5% potassium phosphate was, however, from this point of view less favourable. Acidic and phytotoxic mine spoil from Hungary. Laboratory experiment: plants were grown in pots in a light chamber seed 120 days Heavy metal concentrations (mg/kg) of limed spoil treated with different amendments : Initial contaminant concentration of the substrate Percentual ratio of heavy metals in the plant available fraction of unlimed (without plants) and of limed (after 60 days of red fescue growth) mine spoil: Post-experiment contaminant concentration of the substrate Cd(%) Cu(%) Pb(%) Zn(%) Unlimed 9,1 17,5 24,2 42,5 Limed + red fescue 0,31 0,29 0,05 0,54

6 Phytotechnologies application Post-experiment plant condition Contaminant storage sites in the plant and contaminant concentrations in tissues (root, shoot, leaves, no storage) It was confirmed that red fescue is a metal-tolerant plant when grown in limed and amended (stabilized) mine spoil. All amendments influenced positively the dry matter yield (biomass production) of red fescue, but application of 0.5% potassium phosphate was, however, from this point of view less favourable. All metals were accumulated prevalently in the roots of red fescue. Heavy metal composition (mg/kg) of red fescue after 60 days of growth in limed mine spoil treated with amendments. udl = under detection limit.