scholarly journals Using chemical fractionation and speciation to describe uptake of technetium, iodine and selenium by Agrostis capillaris and Lolium perenne

2020 ◽  
Vol 212 ◽  
pp. 106131
Author(s):  
J. Wang ◽  
E.H. Bailey ◽  
H.K. Sanders ◽  
M. Izquierdo ◽  
N.M.J. Crout ◽  
...  
Keyword(s):  
Lolium Perenne ◽  
Chemical Fractionation ◽  
Agrostis Capillaris

scholarly journals Growth and Persistenceof Common Temperature Pasture Species under Low Light and Low R:FR Ratio

2006 ◽  
Vol 27 ◽  
pp. 111-118 ◽  
Author(s):  
NR Devkota
Keyword(s):  
Lolium Perenne ◽  
White Clover ◽  
Dactylis Glomerata ◽  
Dry Weight ◽  
Holcus Lanatus ◽  
Agrostis Capillaris ◽  
Shoot Dry Weight ◽  
Poa Trivialis ◽  
R:Fr Ratio ◽  
Dactylis Glomerata L

The effects of varied PAR and R:FR ratio on tillering and shoot dry weight production of temperate pasture species were evaluated at Massey University New Zealand using split-plot design with four blocks. The main plots were % transmitted PAR (photosynthetically active radiation; mmoles photons m-2 s-1, 400- 700 nm) and R:FR ratios (red to far red ratios) with 2 x 2 factors of PAR and R: FR, i.e. medium (38 and 39%) and low (16 and 17%) PAR-each with two natural (1.33 and 1.34) and two reduced (0.57 each) R:FR ratios. The treatment combination was such that each low and medium PAR level had a natural and a reduced R:FR ratio. PAR levels with natural R: FR ratio were imposed by differing densities of neutral shade cloth (Sarlon) with a layer of clear filter, while low R:FR ratio was created with the use of a blue filter. Nine pasture cultivars of seven pasture species: Dactylis glomerata L., Grasslands Wana (cocksfoot); Dactylis glomerata L., PG 74 (cocksfoot); Dactylis glomerata L., PG 321 (cocksfoot); Lolium perenne L. (perennial ryegrass); Holcus lanatus L. (Yorkshire fog); Agrostis capillaris (browntop); Poa trivialis; Trifolium repens L. (white clover), and Lotus uliginosus (lotus) were grown in pots as subplots with four replicate blocks. Six plants were maintained per pot. Plants were harvested at 61 days after imposing shade. There was no effect of R:FR ratio (P>0.05) on the shoot dry weight per plant, however, significant differences (P<0.05) for PAR, species, and interaction of PAR, species for shoot dry weight was observed. At low PAR, Lolium perenne, Dactylis glomerata (Wana) and Holcus lanatus had the highest and similar yields, whereas the yield of white clover and lotus were similar and less than for all the grass species. Effects of PAR as well as R:FR were significant (P<0.001) for total tillers per plant in the shade. Poa trivialis, Agrostis capillaris and Lolium perenne had the highest number of tillers/plant at the low PAR and low R:FR, but did not contribute to higher shoot dry weight at the low PAR, mainly due to their low weight per tiller. Likewise, SLA was significantly (P<0.01) increased by low PAR but not by low R:FR. Lotus produced a higher (P<0.001) number of branches at the low PAR than white clover. Comparatively better performance of cocksfoot, especially at low PAR, was mainly due to the ability to produce higher leaf area, higher SLA, and more tillers per plant. The results are discussed in terms of the effects of PAR and R:FR on the yield and yield components with respect to the attributes of shade tolerant pasture species. Key words: PAR, R:FR ratio, wana cocksfoot, nui perennial ryegrass, shade J. Inst. Agric. Anim. Sci. 27:111-118 (2006)

scholarly journals The effect of herbicides and surfactants on turf grasses and annual poa

2000 ◽  
Vol 53 ◽  
pp. 277-283 ◽  
Author(s):  
M.P. Finlayson ◽  
F. Dastgheib
Keyword(s):  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Poa Annua ◽  
Agrostis Capillaris ◽  
Cool Season ◽  
Lolium Perenne L

The tolerance of browntop (Agrostis capillaris L) perennial ryegrass (Lolium perenne L) Chewings fescue (Festuca nigrescens Lam) and annual poa (Poa annua L) to twelve herbicides with and without two organosilicone surfactants (Silwet L77 and Silwet S800) were assessed Annual poa was controlled by haloxyfop and clethodim plus S800 Browntop was highly tolerant to chlorsulfuron and metsulfuron and Chewings fescue to haloxyfop fluazifop clethodim and sethoxydim Organosilicone surfactants affected the tolerance of some species to certain herbicides For example Silwet L77 reduced the tolerance of annual poa to glyphosate but S800 increased the tolerance of perennial ryegrass to terbuthylazine The results have implications for the management of cool season turf

scholarly journals Studies on the sensitivity of some species and cultivars of lawn grasses on salinity with sodium chloride during the seed germination and first year of growth

2008 ◽  
Vol 20 (1) ◽  
pp. 81-98 ◽  
Author(s):  
Edward Borowski
Keyword(s):  
Sodium Chloride ◽  
Lolium Perenne ◽  
Poa Pratensis ◽  
Dry Weight ◽  
Grass Species ◽  
First Year ◽  
Festuca Rubra ◽  
Agrostis Capillaris ◽  
River Sand ◽  
Nacl Salinity

Abstract In the years 2005 - 2006 studies were conducted in a growth chamber and a vegetation hall which compared tolerance to NaCl salinity of seeds and plants of some lawn grasses. The effect of sodium chloride salinity on the germination of 4 species of grasses i.e. Lolium perenne cv. ‘Info’, Festuca rubra cv. ‘Audio’, Agrostis capillaris cv. ‘Niwa’, Poa pratensis cv. ‘Alicja’ and 4 cultivars of Lolium prenne - ‘Nira’, ‘Stadion’, ‘Ronija’, ‘Darius’ was studied. The grass seeds germinated in Petri dishes, in darkness, at the temperature of 24°C. Besides the control, 3 levels of salinity were used in the studies: 100, 200 and 300 mM NaCl. The obtained results demonstrated that the growing level of salinity in the environment significantly decreased the germinating speed, the number of the produced roots, the length of the longest root, and the length of the coleoptile in the seedlings of all studied grass species. Lolium perenne seeds tolerated salinity the best, and next - in a diminishing sequence - those were the seeds of Festuca rubra, Agrostis capillaris and Poa pratensis. However, the obtained data showed that tolerance to salinity of the analyzed cultivars of Lolium prenne decreased in the following sequence ‘Ronija’ > ‘Stadion’ > ‘Nira’ > ‘Darius’. In a vegetation hall tolerance to NaCl salinity of these 4 cultivars of Lolium perenne in the first year growth was compared. The plants grew in pots of 2 dm3 filled with a mixture of universal earth and river sand (3:1 / v:v) with the soil moisture of 70% and 3 levels of salinity: 0, 50, and 100 mM NaCl. The obtained results demonstrated that in all studied cultivars the increase of the salinity level caused a significant decrease of the yield of the leaf dry weight from the successive grass crops, and an increase of the content of sodium, chloride and free proline in them. The greatest tolerance to NaCl salinity in the group of the studied cultivars was shown by ‘Ronija’, medium tolerance - by ‘Darius’ and ‘Stadion’, and the lowest one - by ‘Nira’. This resulted from the degree of accumulation of Na+ and Cl- ions and proline in those conditions. The cultivars with higher tolerance accumulated fewer osmotically active compounds in the leaves.

scholarly journals Extensification of upland pasture in Britain

1994 ◽  
pp. 219-222
Author(s):  
M. Fothergill ◽  
D.A. Davies ◽  
C.T. Morgan
Keyword(s):  
Lolium Perenne ◽  
Trifolium Repens ◽  
Agricultural Policy ◽  
Biological Diversity ◽  
Agrostis Capillaris ◽  
Extensive Grazing ◽  
Livestock Sector ◽  
Upland Pasture ◽  
Set Up ◽  
Profit Maximisation

There is a conflict in British grassland farming between management for agricultural purposes, centring on profit maximisation, and that of nature conservation and the enhancement of biological diversity. Within the European Union's Common Agricultural Policy there is a growing emphasis on reducing output from the community's livestock sector and this is achieved through allocation of quotas (sheep and milk) whilst maintaining alongterm agricultural base. This could result in the widespread adoption of more extensive grazing regimes. An experiment was set up in upland Wales in 1991 to study the effect of reducing inputs and defoliation on species balance and animal production in a Lolium/Agrostis dominant pasture. Spectacular changes in species balance took place in the first grazing season. Elimination of CaPK and N applications encouraged Agrostis capillaris at the expense of Lolium perenne and Poa spp. and led to a 43% reduction in stock carrying capacity by the 3rd year. Where no defoliation took place important pasture species such as Lolium perenne and Trifolium repens were lost from the swards-by-theZ&year:However;-an-annu&midsummer cut maintained these potentially highly productive species within the sward. Keywords: extensive grazing, low inputs, ryegrass, sheep, species balance, Trifolium repens, upland Britain

scholarly journals Selectividad de Bromus valdivianus Phil., Lolium perenne L. y Agrostis capillaris L. por vacas lecheras en pastoreo

Agro Sur ◽  
2016 ◽  
Vol 44 (3) ◽  
pp. 53-65
Author(s):  
I. F. López ◽  
O. A. Balocchi ◽  
X. Álvarez ◽  
P. Flores ◽  
L. Latrille
Keyword(s):  
Lolium Perenne ◽  
Agrostis Capillaris ◽  
Lolium Perenne L

scholarly journals Ajustes morfo-fisiológicos de Lolium perenne L. y Agrostis capillaris L. como respuesta a la disminución de la luz incidente

Agro Sur ◽  
2018 ◽  
Vol 46 (2) ◽  
pp. 35-48
Author(s):  
P. G. Flores ◽  
I. F. López ◽  
P. D. Kemp ◽  
J. Dörner ◽  
B. Zhang
Keyword(s):  
Lolium Perenne ◽  
Agrostis Capillaris ◽  
Lolium Perenne L

Techniques for preparing the Lolium perenne coleorhiza for scanning electron microscope evaluation

1992 ◽  
Vol 50 (1) ◽  
pp. 766-767
Author(s):  
Susan B.G. Debaene ◽  
John S. Gardner ◽  
Phil S. Allen
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Lolium Perenne ◽  
Morphological Study ◽  
Root Hairs ◽  
Inner Pressure ◽  
Water Potentials ◽  
Radicle Emergence ◽  
Standard Fixation ◽  
Scanning Electron

The coleorhiza is a nonvascular sheath that encloses the embryonic radicle in Poaceae, and is generally the first tissue to emerge during germination. Delicate hairlike extensions develop from some coleorhiza cells prior to radicle emergence. Similar to root hairs, coleorhiza hairs are extremely sensitive to desiccation and are damaged by exposure to negative water potentials. The coleorhiza of Lolium perenne is somewhat spherical when first visible, after which a knob forms at a right angle to the caryopsis due to inner pressure from the elongating radicle. This knob increases in length until the radicle finally punctures the coleorhiza. Standard fixation procedures cause severe desiccation of coleorhiza cells and hairs, making morphological study of the coleorhiza difficult. This study was conducted to determine a more successful process for coleorhiza preservation.

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