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Perspektywy hodowli Lolium perenne

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Lolium perenne is a species characterized by wide adaptive variability. This feature is responsible for creative breeding of fodder and turf varieties. This species has been bred for more than 100 years. During this time dozens of fodder varieties were produced with the use of classic breeding methods. The varieties were characterized by high feeding qualities. Besides, many turf varieties were with excellent utility and visual qualities were produced. New trends in biotechnology, especially in molecular diagnosis and genetic engineering, create many opportunities for widening the genetic variability for the breeding of new, improved and specialized varieties.
On the ground of bibliography in this paper were presented numerous results of investigations on the point of Lolium perenne occurrence in Poland, in the sward of permanent grassland in Poland, according to the natural and anthropogenie factors. Lolium perenne was of frequent occurrence in Poland in the different habitats of permanent grasslands. The most favorable conditions Lolium perenne finding in the low pastures sward of Lolio-Cynosuretum association and in the excessively treaded down sward of Lolio-Plantaginetum association. The main factors reducing the oceurrence of Lolium perenne sward of permanent grassland are: low temperatures of air (especially in the early-spring period), excess or indigence of water in the soil, excess or indigence of elements in the soil, mowing use or excessive grazing, in the mountain altitude of 700 m a.s.l. and high rivalry of concurrent species.
English ryegrass (Lolium perenne L.) comes originally from England, where it has been grown since 1680. The study presents the most important morphological and biological features of Lolium perenne. Because of those mostly positive features Lolium is very suitable to different turf use (on gazons, sport fields, recreations area and so on) Lolium perenne is able to produce more than 10 thousand tillers per 1 m², has a good ability to different management, good response for nitrogen fertilisation and it is resistance for low and frequently cutting. Some of Lolium disadvantages do not change the opinion that it is one of the most important turf grasses in Poland and Europe.
The effectiveness of perennial ryegrass plantations, and hence their profitability, depends, to a considerable extent, on the specificity of the reproduced cultivar. The most appropriate strategy for maintaining high seed yields of new grass cultivars, apart from the improvement of their fodder and lawn aspects, is to seek to obtain the highest seed yield calculated per one generative shoot. In order to increase the efficiency of perennial ryegrass seed plantation it is necessary, apart from the improvement of the seeding aspect of a given cultivar by way of breeding work, also to improve technology of their cultivation. This target can be reached by optimization of agrotechnical factors stimulating biological reproductive potentials of cultivars. Results of own studies indicate that there is an optimal state of nitrogen concentration of perennial ryegrass plants in successive growth stages, which guarantees obtaining the highest seed yields on plantations. In the case of ‘Maja’ cultivar, the content of nitrogen in leaf blades at the beginning of vegetation should amount to 47 g kg⁻¹ DM and at the car initiation - 51 g kg⁻¹ DM. in the case of ‘Anna’ the optimal concentration of nitrogen in leaf blades were 54 and 57 g kg⁻¹ DM, respectively. Another very important factor is the determination of the optimal time and method of harvest as they affect the level of losses of the produced seed yield. The optimal time of seed harvest on perennial ryegrass plantations is the drop of sugars in kernels to the level of 5% DM. The increase of yields from seed plantations of Lolium perenne is a strategic matter for Polish grass seed production, which constitutes an important segment of the domestic seed industry.
The contents of organic and mineral components in 18 cultivars of Lolium perenne L. were compared. The result of chemical analyses came from two Experimental Strain Test Stations: at Śrem (Great Poland) and at Bukówka (Sudetic Mountain Region). Chemical analyses of the first outgrowth of the cultivars were carried out in the first year of full utilization (1997). The plants were cut down at full heading stage of the cultivars. The contents of N-free extract compounds in all the cultivars coming from the Sudetic Mountain Region appeared higher than those in samples from the Great Poland. At both the Stations the tetraploid cultivars were characterized by an above average content of N-free extract. Inverse relations were found in case of the quantity of fibre and ash components. The average contents of total protein were similar in both the habitats. The cultivars from the Sudetic Mountain Region were characterized by a greater amount of metabolic energy (from 10.79 to 11.94 MJ in 1 kg of DM). It could have been influenced by a higher amount of N-free extract compounds contained in the plant mass of all the cultivars, what has been corroborated by a higher value of the coefficient of correlation between the amount of metabolic energy and N-free extract. The cultivars 'Anduril', 'Barylou', 'Bravo' and 'Canasta' appeared to have been off less feeding value (as expressed by means of Emetabol) irrespective of habitat. Now, above-average feeding value was found in the cultivars 'Barezane', 'Kelibia', 'Hercules' and 'Solen'. Stronger response to the habitat conditions was that of the cultivars 'Arka', 'Fanda' and 'Napoleon'.
Lolium perenne is unique in its advantageous chemical composition, considerable palatability and high digestibility. This high assessment is also corroborated by Polish investigations. Moreover, this evaluation is the result of high energetic value of forage obtained from Lolium perenne plantations. It is possible to obtain high quality ryegrass sward in Polish climatic and soil conditions, provided appropriate treatment of grasslands is assured, in particular, its proper utilization. It must be remembered that this grass is susceptible to thermal and water stresses, which may not only modify plant chemical composition but also decrease its persistence. Therefore, the utilization of this grass in Poland for animal nutrition is determined not only by its chemical properties but also by plant persistence and, associated with it, risk of its cultivation.
Tests in 1996-2002 were carried out to evaluate the usefulness of 8 cultivars and strain of Lolium perenne L. (Polish - 'Anna', 'Arka', 'Maja', 'Rela'. 'Solen' and strain SZD-291 as weil as Dutch - 'Baristra', 'Barezane' and 'Barlano' ) to mixtures for cutting performance under peat-bog soil conditions. No influence of perennial ryegrass (30-35% of share in mixtures) on significant differentiation of dry matter yields in relation to those without that species was recorded. The share of perennial ryegrass in achieved fodder was significant during first 4-6 years after sowing (about 20-45%), which ensured higher stability of species composition of meadow sward with tendency to decreasing in last years. Share of perennial ryegrass in meadow sward mixtures systematically decrcased in last years. Durability of the species significantly depended on included cultivars. 'Anna', 'Maja', 'Solen', 'Barlano' and 'Baristra' were characterized with higher and more stable share in sward during studies as compared to 'Arka', 'Rela' and 'Barizane' cultivars.
Lolium perenne L. is the most attractive and widespread grass species used to prepare lawn mixtures applied in the temperate zone. This extensive utilisation of the species is the function of its valuable biological and use properties. The ability of this grass to develop numerous vegetative shoots as weil as its strongly developed root system assure Lolium perenne a share in the sward of both extensive lawns and very intensively utilised grass carpets. Long-term perspectives for Lolium perenne as a turf grass rest, primarily, in the breeding of specialised cultivars. When developing breeding programs, breeders utilise the considerable variability of biological and morphological traits of this grass species. It has already been possible to create cultivars which develop very rapidly after sowing, e.g. 'Darius' or cultivars which form exceptionally dense turf which can withstand even very intense trampling, e.g. 'Margarita'. According to our own investigations, differences in the dynamics of turf compaction may reach several dozen percent. One of the unique properties of the newly developed cultivars is their capacity to rapidly develop new stalks and leaf-blades after turf damage, the so-called turf exhaustion. One of the effects of performed breeding work is the development of Lolium perenne cultivars characterised by very narrow leaf blades, comparable with the width of leaf-blades of Festuca rubra. A good example of such a cultivar is 'Bargold'. In the process of reclaiming difficult areas, where access is limited, slower rates of biomass regrowth of over-ground parts after cutting are essential. The most useful for this purpose are cultivars of Lolium perenne whose daily height regrowths, in periods of most intensive growth, (in May, at the beginning of September) do not exceed 0.6 cm. As a rule, late cultivars are characterised by slower increment of over-ground biomass.
From among different possibilities of Lolium perenne use in green areas, this species is most useful for transferable sod production which can by applied for interior decoration (pavilions, exhibitions) as well as for the decoration of hardened open space in towns (squares, pavements, terraces), also for arranging ornamental lawns in gardens, and for strengthening the surface of slopes and heaps in green areas and side space in road building. The basic species for transferable lawns preparing are: Lolium perenne with the cultivars ‘Gazon’, both creating a strong root system, which is a main condition of compactness indispensable for transportation the sod to the place of its destination.
The aim of this study is to show the role of Lolium perenne L. in the carpet plant communities which develop on trampled places such as: roadsides, wastelands, playgrounds, sport fields, lawns, railway areas in the Upper Silesian Industrial District. In order to recognise plant communities there were made 120 phytosociological relevés. There were recognized 5 plant communities which are built mainly by annuals from Polygono-Poëtea class (Polygonetum calcati, Sagino-Bryetum, Puccinellio-Chenopodietum, Poëtum annuae, Matricario-Polygonetum) and 5 in structure of which the main role play hemicryptophytes from Molinio-Arrhenatheretea class, Trifolio-Plantaginetalia order, Cynosurion (Lolio-Plantaginetum, Juncetum macri), and Agropyro-Rumicion (Potentilletum anserinae, Potentilletum reptantis, Odontites serotine community) alliances. In carpet plant communities occur from 3 to 25 grasses, and their participation in the floristic list range from 12% to 32%. Lolium perenne was recorded in almost each plant community with the exception of Sagino-Bryetum. The highest percentage participation in the plant cover it has in Odontites serotina community and Lolio-Plantaginetum phytocoenoses. In the lalter one it has it ecological optimum.
Seed production in warmian-mazurian voivodeship has signify position in Poland and considering that favourable nature terms and relatively satisfied yields this position seems to be solid. The main species in grass seed production on this area is perennial ryegrass, particularly ‘Nadmorski’ (‘Naki’) cultivar. Increasing number of plantation is a positive fact, as also area stabilization of gazon cultivars, particularly ‘Stadion’ cultivar. Seed production of perennial ryegrass is concentrated in Iława, Ostróda and Nowe Miasto districts - above 80% seed plantation area. This is zone of Rolimpex S.A. activity – the biggest contracting party of seed grasses, particularly perennial ryegrass in voivodeship.
On the basis of 4000 phytosociological surveys taken using the Braun-Blanquet method, it was found that Lolium perenne occurs in meadow-pasture communities of 5 phytosociological classes, namely: Molinio-Arrhenatheretea, Phragmitetea, Koelerio glaucae-Corynephoretea canescentic, Scheuchzerio-Caricetea fuscae and Agropyretea intermedio-repentis. The highest proportion of this species occurred in Molinio-Arrhenatheretea, which is associated with site conditions and the level of utilisation. The share of Lolium perenne in the identified communities showed variations between river valleys. It was found to occur most frequently and numerously in valleys of such smaller rivers as: the Barycz, the Rów Ostroroski, the Mogilnica, the Sama Szamotulska. The development of degradation forms of communities in the Molinio-Arrhenatheretea class containing Lolium perenne was associated mainly with the impact of the anthropogenic factor, in particular with limited fertilisation and grazing (sometimes with its complete abandonment). In communities of the remaining classes, the factor limiting the share of Lolium perenne was site conditions, primarily poor soil fertility and different ways of utilisation. In areas situated at foothills and seaside, Lolium perenne occurs less frequently and at a lower share in meadow-pasture communities, which can be associated with utilisation intensity and non-forage functions.
In studies performed in 1998-2001, yielding and sward species composition of six mixtures performed for pasture with Lolium perenne participation was compared. Studies revealed that species share in pasture fodder achieved was variable both depending on species composition or mixtures sown, soiI conditions and year of performance. Yielding and species composition of six mixtures performed for pasture (BG-5 and BG-6 by Barenburg, Mkb-1 and Mkb-2 by Land O’Lakes as well as P-1 and P-2 by Rolimpex), with special attention paid to Lolium perenne L. share was compared in studies carried out in 1998-2001. Above mixtures were sown onto two pasture quarters of about 1 ha area cach in band design. Particular mixtures covered the area of about 0,165 ha each. Quarters differed with soiI conditions (one localized on mucky-peat, the other on mucky-mineral soil). The share of Lolium perenne cultivars in mixtures sown (1998) ranged from 9,5% (P-2) up to 15,8% (Mkb-2). Sward in studied quarters was performed for grazing in 1999-2001 (4 cuts), except from the first cut in 1999 and 2001. The first cut was harvested in this period because of long-term excessive humidity. The share of Lolium perenne in pasture fodder achieved was variable both depending on species composition of mixtures sown, soil conditions, and year of performance. In 1999, the share of Lolium perenne was higher in the sward of mixtures on mucky-mineral soil. Soil conditions in 2000-2001 did not affect the species share. In the third year of experiment (2001), also great differentiation of Lolium perenne share in the sward depending on mixture type was found. The least share of the species was observed in the sward of P-1 mixture (25,9-31,4% ), the highest in the sward of BG-5 mixture (61,7-62,7% ).
The objective of the research project was to assess the effectiveness of application of some selected herbicides (Table 1) in seed plantation of Lolium perenne (cv. 'Anna' 2n PL) established in late-summer pure sowing in the first year of utilization. The field experiment was carried out in two series in years 1998-2000 in the experimental Station in Brody. Depending on the specificity of the herbicides, they were applied (using a plot field sprayer) either in the autumn when perennial ryegrass was at the stage of 3-4 leaves or in early spring, when plants of Lolium perenne were at the stage of full tillering and four weeks later. The following parameters were evaluated: weed control efficacy, seed yield, number of generative shoots, number of spikelets per ear, 1000 seed weight, germination and purity of seeds as weil as the profitability index of the applied herbicides. It was found that the highest weed control efficacy reaching the level of 96% was recorded in the case of Lentagran 45 WP. The autumn application of this herbicide was more profitable in comparison with the spring application. The application of Lentagran 45 WP, also in combination with Stomp 330 EC, resulted in 137% increase of seed yield. In the case of the spring herbicide treatment, the highest effectiveness was observed when the mixture of Aminopielik D 450 SL + Chwastox D 179 SL + Starane 250 EC was used. From tested herbicides, the following ones are not suitable for weed control in Lolium perenne seed plantations: Arelon Fox 550 EC, Dicuran 80 WP, Glean 75 WG and Attribut 70 WG. The above mentioned herbicides caused damage to perennial ryegrass and secondary weed infestation leading to lower seed yields. In addition, the application of Attribut 70 WG resulted in reduced seed vitality. The observed enhancement of the seed yield of Lolium perenne was due to higher density of generative shoots, higher number of spikelets per ear and higher 1000 seed weight.
The perennial ryegrass (Lolium perenne L.) is a valuable species frequently used to establish permanent grasslands and to renew them. This study is an attempt to evaluate the viability of the ‘Arka’ cultivar in mountainous area with different management systems. From 1992 to 1997 three field experiments had been conducted. In the first a hay meadow set up on arable land was involved and the perennial ryegrass was sowed alone or in a five-species mixture. The meadow was cut twice a year and fed with minerals (P₂O₅ - 60; K₂O - 80; and N - 120 kg ha⁻¹). The second experiment was carried on a pasture renewed by undersowing with perennial ryegrass in a mixture with white clover. The pasture was grazed four times a year and fed respectively with 60, 80 and 60 kg of P₂O₅, K₂O and N per hectare. The third experiment was located on a permanent pasture and aimed at the evaluation of a specific Lolium perenne ecotype as to its response to different grazing regimens (grazed 4 or 5 times a year) and to the increasing dose of nitrogen fertilisation (60, 120 or 180 kg ha⁻¹). The other nutrients (P₂O₅, K₂O) were used on the same level. These experiments have proved a poor durability of perennial ryegrass cv. ‘Arka’ both on the meadow and on the pasture as well. In three-year period its content in the total crop of the grassland has radically decreased. In the pasture experiment the local ecotype of Lolium perenne was characterised by remarkable durability and its growth was especially stimulated by intensive grazing with N-fertilisation level of 120 kg per hectare.
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