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Full-Text Articles in Weed Science

Economic Analysis Of The Impact Of Management Decisions On Production And Use Of Silage For A Dairy Enterprise, A J. Corrall, H D. St. C Neal, I M. Wilkinson Jun 2026

Economic Analysis Of The Impact Of Management Decisions On Production And Use Of Silage For A Dairy Enterprise, A J. Corrall, H D. St. C Neal, I M. Wilkinson

IGC Proceedings (1977-2023)

The aim of this work was to examine the influence of variations in grass management and methods of ensiling on the economics of milk production for autumn-calving cows. A simulation model was developed to combine knowledge of plant and animal responses and their interactions in order to calculate the effects of management options on economic balances. Input data were compiled for herbage production from cut­ting strategies that gave herbage at four digestibilities, at two levels of applied nitrogen, and in three climates. Experimental evidence was also collated to construct matrices of loss of dry matter and changes in digestibility and …


Effect Of Sheep And Cattle Grazing On A Mixed Pasture Of Perennial Ryegrass, Kikuyu, And White Clover, G J. Goold Jun 2026

Effect Of Sheep And Cattle Grazing On A Mixed Pasture Of Perennial Ryegrass, Kikuyu, And White Clover, G J. Goold

IGC Proceedings (1977-2023)

Mixed pastlkes of perennial ryegrass (Lolium perenne L. ), kikuyugrass (Pennisetum clandestinum Hochst. ), and white clover (Trifolium repens L.) are commonly found within warm-zone areas of New Zealand but are frequently disliked because of prob­lems associated with kikuyugrass dominance. A grazing experiment was conducted to provide basic information on the response of such swards to grazing by cattle and sheep. The pastures were rotationally grazed with young sheep or cattle at two stocking levels each year from 1970 to 1975, with stocking rates adjusted twice yearly according to seasonal pasture growth. The pastures grazed by cattle …


Dynamics Of Herbage Growth And Senescence In A Mixed-Species Temperate Sward Continuously Grazed By Sheep, J S. Bircham, J Hodgson Jun 2026

Dynamics Of Herbage Growth And Senescence In A Mixed-Species Temperate Sward Continuously Grazed By Sheep, J S. Bircham, J Hodgson

IGC Proceedings (1977-2023)

Four perennial ryegrass (Lolium perenne L.)-Poa annua L.-white clover (Trifolium repens L.) swards with herbage mass rang­ing from 500 to 1,700 kg organic matter (OM)/ha were established and maintained in as near a steady state as possible by con­tinuous but variahle stocking with sheep in order to study the influence of herbage mass on rates of herbage growth (G), senescence (S), and net production (NP), and on species balance. Estimates ofG, S, and NP were derived from measurements on individual grass tillers and clover stolon growth sites. The mean contributions to total G were 54, 20, and 4 ( ± …


Effect Of Herbage Mass And Allowance Upon Herbage Intake By Grazing Dairy Cows, J.A C. Meijs Jun 2026

Effect Of Herbage Mass And Allowance Upon Herbage Intake By Grazing Dairy Cows, J.A C. Meijs

IGC Proceedings (1977-2023)

An adequate supply of nutrients for grazing animals depends on the intake and nutritive value of herbage. Little information is available on factors affecting herbage intake of grazing cows, particularly for grazing systems that do not involve daily change of animals to a new pasture. Our objectives were to determine the effects of variation in herbage mass ( due to variation in stage of maturity) and of herbage allowance on herbage intake by grazing dairy cows and on efficiency of consumption (herbage con­sumed as a proportion of herbage accumulated). From 1976 to 1979 the herbage intake oflactating cows was determined …


Effects Of Treading And The Return Of Excreta On A Perennial Ryegrass - White Clover Sward Defoliated By Continuously Grazing Sheep, M L. Currl, R J. Wilkins May 2026

Effects Of Treading And The Return Of Excreta On A Perennial Ryegrass - White Clover Sward Defoliated By Continuously Grazing Sheep, M L. Currl, R J. Wilkins

IGC Proceedings (1977-2023)

Grazing sheep may affect the association between grass and clover in a mixed sward by defoliation, treading, and the circula­tion of nitrogen (N) via excreta. Our objective was to examine the effect of treading and excreta on a perennial ryegrass (Lolium perenne)-white clover (Trifolium repens)sward defoliated by sheep at high and low stocking rates. Established swards of perennial ryegrass and white clover were continuously stocked from May to October with yearling wether sheep at 25 and';5() head/ha. Sward production and species composition were measured inside graze-through cages that allowed defoliation without treading and excreta return, and …


Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons May 2026

Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons

IGC Proceedings (1977-2023)

To improve our understanding of grassland utilization under grazing, the physiology of a grazed sward was investigated. An enclosure method, infrared gas analysis, and radiocarbon were used to measure sward and single-leaf photosynthesis and assimilate utilization. Intake by sheep was also measured. Expanding and recently expanded leaves had high rates of net photosynthesis but leaf sheaths, whose projected area in a "hard" grazed sward equaled that of the lamina, had low efficiency and contributed little to canopy photosynthesis. But because high leaf efficiency did not compensate for the small leaf area, canopy photosynthesis decreased markedly as grazing intensity increased. Twice …


Prediction Of The Supply Of Soil Nitrogen To Grass, D C. Whitehead May 2026

Prediction Of The Supply Of Soil Nitrogen To Grass, D C. Whitehead

IGC Proceedings (1977-2023)

Predictions of the supply of soil nitrogen (N) to grass over a growing season requires an assessment of nitrate N plus am­monium N (1) present in the soil at the beginning of the season and (2) likely to be released from the potentially mineralizable organic N during the season. Although a number of methods have been proposed for predicting soil N supply, and in particular the component arising from the potentially mineralizable N, many are too time consuming for routine use, and others have not been proven effective over a range of soils. However, in recent studies, the measurement of …


Effective Selection For Tolerance To Grass-Killing Herbicides In Perennial Ryegrass (Lolium Perenne L.), C E. Wright, J S. Faulkner May 2026

Effective Selection For Tolerance To Grass-Killing Herbicides In Perennial Ryegrass (Lolium Perenne L.), C E. Wright, J S. Faulkner

IGC Proceedings (1977-2023)

The aim of grassland reseeding is to establish a high-quality sward of improved herbage cultivars. To obtain the maximum value from the improved sward, weed invasion should be prevented. Herbicides are the main tool available. There are many herbicides for selectively controlling dicotyledonous, but not graminaceous, weeds. The control of graminaceous weeds would be possible in swards of grass cultivars selected for tolerance to grass-killing herbicides. Two cycles of recurrent selection for glyphosate tolerance in Lolium perenne L. were carried out by spraying large seedling populations with critical dosages in the greenhouse and intercrossing the survivors. It was found that …


Endophyte Fungus Increases Persistence Through Improved Pest Control, R A. Prestidge, G M. Barker, R P. Pottinger, K W. Steele Jul 2025

Endophyte Fungus Increases Persistence Through Improved Pest Control, R A. Prestidge, G M. Barker, R P. Pottinger, K W. Steele

IGC Proceedings (1977-2023)

Our objectives were to determine (1) the feeding and oviposition behaviour of Argentine stem weevil Listronotus bonariensis Kuschel feeding on ryegrass infected with Acremonium endophyte, and (2) to survey pastures to relate ryegrass content, Argentine stem weevil populations and larval damage to the incidence of Acremonium endophyte in pastures of known age. In preference tests, adult stem weevil fed more extensively and deposited more eggs on endophyte-free ryegrasses. Ryegrass content in surveyed pastures in the central North Island of New Zealand averaged only 35% of the sward after 2-3 years. The majority of rye grass plants were infected with Acremonium …


Mutual Influence Of Temperate Legumes And Grasses Grown In Association At Different Nitrogen Levels, E Meister, J Lehmann Jul 2025

Mutual Influence Of Temperate Legumes And Grasses Grown In Association At Different Nitrogen Levels, E Meister, J Lehmann

IGC Proceedings (1977-2023)

In grass/legume associations white clover (Trifolium repens), red clover (Trifolium pratense) and alfalfa (Medicago sativa) contribute significantly to the nutritive value of such mixtures. Compared to Italian ryegrass (Lolium italicum), perennial ryegrass (Lolium perenne) and orchard grass (Dactylis glomerata ), the legumes have an inherently higher content of protein, magnesium and calcium. In addition they indirectly help to improve the quality (protein and mineral content) of the companion grass, presumably over a nitrogen transfer from the legume to the grass partner: On the other hand, the chemical composition of these …


Competition Effects On Nitrogen Fixation And Mineral N Uptake In Trifolium Repens L.- Lolium Perenne L. Associations, C P. West, K W. Steele, E A. Halligan Jul 2025

Competition Effects On Nitrogen Fixation And Mineral N Uptake In Trifolium Repens L.- Lolium Perenne L. Associations, C P. West, K W. Steele, E A. Halligan

IGC Proceedings (1977-2023)

Improved While clover (Trifolium re pens L.) cul ti vars can potentially increase the input of nitrogen (N) from symbiotic fixation into clover-grass pastures and maintain elevated N2 fixation rates in the presence of nitrogenous fertilizers. The objective of this study was to determine the effects of interspecific competition on N2 fixation and mineral N uptake in white cover-perennial ryegrass (Lolium perenne L.) associations with either a medium-small ('Grasslands Huia') or large leaved ('G18') cultivar. The clover and grass were grown in a controlled environment room in pots that were partitioned to allow either no interspecific competition for shoots and …


A Simulation Model Of The Seasonal Pattern Of Herbage Digestibility And Its Interaction With Intensity Of Defoliation, A W. Illius Jul 2025

A Simulation Model Of The Seasonal Pattern Of Herbage Digestibility And Its Interaction With Intensity Of Defoliation, A W. Illius

IGC Proceedings (1977-2023)

Despite the considerable efforts expended in studying the seasonal changes in the digestibility of herbage under different harvesting regimes, there has only been slow progress in the modelling of these processes. In this paper, a quantitative description of the factors underlying seasonal changes in herbage digestibility is developed and applied to sets of data from S24 and S23 perennial ryegrass. A new variable, relative maturity, is used to describe the effect of defoliation in interrupting the process of tiller maturation which leads to the decline in digestibility. For S24, the model explained 95.5% of variation in digestibility decline, allowing accurate …


Influence Of Temperatures On The Earliness Of Heading And Nutritive Value Of Two Grasses During The First Growth Cycle, J Andrieu, M Berekoutou May 2025

Influence Of Temperatures On The Earliness Of Heading And Nutritive Value Of Two Grasses During The First Growth Cycle, J Andrieu, M Berekoutou

IGC Proceedings (1977-2023)

The two objectives of this study were: I) to see if the method of the sums of temperatures allowed for a correct prediction, not only of the earliness of heading but also of the quality of spring growth whatever the surrounding conditions ; 2) to check that the criteria, suggested jn the feed Tables published by INRA in France (INRA 1981; INRA 1988) to predict the quality of spring growth, could be used for the whole of France. This study is drawn from the thesis ofM. Berekoutou (1986).


Plant Improvement Using Endophytic Fungi, G C.M Latch Apr 2025

Plant Improvement Using Endophytic Fungi, G C.M Latch

IGC Proceedings (1977-2023)

Endophytic fungi which grow intercellularly in many species of grasses have been a scientific curiosity for almost a century. The mycelium of many of these fungi never emerges from the plant and the fungus is disseminated by way of hyphae in the seed. Other endophytes such as Epichloe typhina form a myce­lial weft around the developing inflorescences thus preventing seed formation. Grasses infected with endophytes usually appear healthy and the presence of the fungus can only be detected by examining tissues from leaf, sheath, culms and seed for fungal mycelium. The economic importance of these fungi was first discovered by …


La Definition De La Date Optimale De La Premiere Pature De Quelques Especes Et Varietes De Graminees Fourrageres, B Rutkowska, E Lewicka, A Kolakowska Apr 2025

La Definition De La Date Optimale De La Premiere Pature De Quelques Especes Et Varietes De Graminees Fourrageres, B Rutkowska, E Lewicka, A Kolakowska

IGC Proceedings (1977-2023)

La rationalisation du piiturage depend aussi de la date de la piiture, particulierement au printemps, au moment de la pre­miere ou de la deuxieme piiture quand !es tiges floriferes des graminees commencent a se developper (Allerit, 1978 ; Gillet, 1980). On sait que la meilleure periode pour debuter le piiturage se situe lorsque les plantes ont 20-25 cm de hauteur, !es ani­maux mangent mieux et !es pertes par pietinement sont limi­tees. En dehors de cela !es resultats des experiences frarn;aise et suisse (Caputa, 1975; Gillet et al., 1980) montrent qu'a cette hauteur !es jeunes tiges floriferes ont une hauteur de …


Nitrogen And Carbohydrate Mobilizations During Regrowth Of Defoliated Lolium Perenne L., A Ourry, B Gonzalez, J Bigot, J Boucaud, J Salette Apr 2025

Nitrogen And Carbohydrate Mobilizations During Regrowth Of Defoliated Lolium Perenne L., A Ourry, B Gonzalez, J Bigot, J Boucaud, J Salette

IGC Proceedings (1977-2023)

It is generally reported that carbohydrate and organic nitro­gen reserves contribute to re-growth of new foliage in perennial grassland species subjected to clipping management. Only few studies are concerned with the comparative pattern of the mobilization, translocation and recovery of carbohydrate and nitrogen reserves during re-growth following defoliation. Davidson and Milthorpe (1966) have suggested that proteins are mobilized to produce energy in the absence of photosyn­thate whereas non-structural carbohydrates are generally con­sidered as the major organic reserves mobilized during re­growth (White, 1973). The objective of this study was to determine the origin of the mobilized nitrogen compounds and to follow …


Characteristics Of Grass Species In Pasture For High Producing Cows In Northern Japan, K Sudo, K Ochiai, T Ikeda Jul 2024

Characteristics Of Grass Species In Pasture For High Producing Cows In Northern Japan, K Sudo, K Ochiai, T Ikeda

IGC Proceedings (1977-2023)

The prupose of this research was to investigate characteristics of grass species under different conditions appropriate to the intensive grazing system for high producing cows (8000 kg for a 305-day lactation) in northern Japan. Meadow fescue (Festuca elatior L.), timothy (Phleum pratense L.) and perennial ryegrass (Lolium perene L.) white clover (Trifolium repens L.) pastures were established and divided into two plots by difference of regulated plant height (meadow fescue and timothy) or of stocking intensity (perennial ryegrass). Each plot was 60m2 and was grazed when plant height reached 20cm or 30cm. Meadow fescue and perennial …


The Effect Of Grazing Management Options On The Persistence Of Perennial Ryegrass In The Temperate Winter Rainfall Zone Of Southern Australia, John F. Graham, Tim Prance, Robin Thompson Jul 2024

The Effect Of Grazing Management Options On The Persistence Of Perennial Ryegrass In The Temperate Winter Rainfall Zone Of Southern Australia, John F. Graham, Tim Prance, Robin Thompson

IGC Proceedings (1977-2023)

This study examined grazing management options on perennial ryegrass (Lolium perenne) based pastures to determine if perennial ryegrass could be increased in a degraded pasture, or maintained in a newly sown pasture. Study sites were at Hamilton and Cavendish, Victoria; Delamere, South Australia, and Ross and Parattah, Tasmania. Average rainfall is 500mm at Ross, 575mm at Parattah, 700mm at Hamilton, 650mm at Cavendish and 900mm at Delamere. At all sites, 8 core grazing management treatments were imposed, and up to 4 “local options.” Changes in botanical composition indicate that grazing management can influence the amount of perennial ryegrass …


Pasture Species For Grazing-Based Dairy Production Under Irrigated In The Intermountain West, J W. Macadam, R E. Whitesides, M B. Winger, S Buffler Jun 2024

Pasture Species For Grazing-Based Dairy Production Under Irrigated In The Intermountain West, J W. Macadam, R E. Whitesides, M B. Winger, S Buffler

IGC Proceedings (1977-2023)

Forage trials were established in response to producer interest in grazing-based dairy production. The quantity and seasonal distribution of yield of tall fescue (Festuca arundinacea Schreb.), orchardgrass (Dactylis glomerata L.), white clover (Trifolium repens var. giganteum L.), birdsfoot trefoil (Lotus corniculatus L.), and cicer milkvetch (Astragalus cicer L.) harvested three times were similar, with about half the production occurring in June. Legume quality was higher in June, and quality for all species was highest in late summer. Yields of perennial ryegrass (Lolium perenne L.), meadow bromegrass (Bromus riparius Rehm.) and Kentucky bluegrass (Poa pratensis …


Sward Structure Change And Production Increases Following Spring Grazing Management, A Hernandez Garay, J Hodgson, C Matthew Jun 2024

Sward Structure Change And Production Increases Following Spring Grazing Management, A Hernandez Garay, J Hodgson, C Matthew

IGC Proceedings (1977-2023)

The objective of this experiment was to study sward structure effects on production of perennial ryegrass-white clover swards with and without white clover following lax spring grazing periods of different duration. Two periods of 6 (short release - SR) and 12 (long release - LR -) weeks of lax grazing were compared against a conventional hard grazing throughout (early control - EC). Treatments were arranged in a factorial design with 3 replicates. Changes in sward structure were reflected in herbage production before (spring) and after the control period (summer-autumn). During spring, herbage mass was increased as a consequence of an …


Genetic Variation In Perennial Ryegrass For Volatile Fatty Acid Production In Rumen Fluid, H.J P. Marvin, E N. Van Loo, O Dolstra, C.H A. Snijders, D Reheul, J W. Cone Jun 2024

Genetic Variation In Perennial Ryegrass For Volatile Fatty Acid Production In Rumen Fluid, H.J P. Marvin, E N. Van Loo, O Dolstra, C.H A. Snijders, D Reheul, J W. Cone

IGC Proceedings (1977-2023)

In perennial ryegrass genetic variation was shown not only for in vitro organic matter degradation (OMD) in rumen fluid and neutral detergent fibre content (NDF) but also for production of volatile fatty acids (VFAs) upon in vitro incubation in rumen fluid. The correlations among concentrations of VFAs in the incubation fluid were high. OMD and NDF, on the other hand, were poorly correlated to the VFA concentrations.


Gene Transfer Of Ryegrasses: Down-Regulation Of Major Pollen Allergens In Transgenic Plants, X L. Wu, X D. Ye, Z Y. Wang, I Potrykus, G Spangenberg Jun 2024

Gene Transfer Of Ryegrasses: Down-Regulation Of Major Pollen Allergens In Transgenic Plants, X L. Wu, X D. Ye, Z Y. Wang, I Potrykus, G Spangenberg

IGC Proceedings (1977-2023)

The objective of this study is to generate transgenic ryegrass plants with a down-regulation of two major pollen allergenic proteins Lol p I and Lol p II. Antisense vectors for Lol p I and Lol p II cDNAs driven by the pollen-specific promoter Zm13 have been constructed. Corresponding transgenic plants have been recovered by particle inflow gun-mediated microprojectile bombardment of embryogenic suspension cells from perennial and Italian ryegrass using chimeric Act1-hph gene as a selectable marker. Their transgenic nature has been demonstrated by Southern hybridization analysis. The analysis of reproductive development and accumulation of pollen allergens in the transgenic ryegrasses …


Influence Of The Acremonium Endophytes On Agronomic Traits Of Perennial Ryegrass And Tall Fescue In France, C Ravel, F Balfourier, G Charmet Jun 2024

Influence Of The Acremonium Endophytes On Agronomic Traits Of Perennial Ryegrass And Tall Fescue In France, C Ravel, F Balfourier, G Charmet

IGC Proceedings (1977-2023)

Seven cultivars of perennial ryegrass (Lolium perenne) with (EI) and without (EF) Acremonium endophytes were compared in trial plots at 5 locations in France. Such a trial was also established with 6 tall fescue (Festuca arundinacea) cultivars in 5 locations. These trials were sown either in 1994 or 1995. Yields and visual traits (rust and drought tolerances, vigour 6-weeks following the sowing) were assessed. The data were analysed by means of variance analysis with two main factors (cultivars and endophyte status) and their interaction. As interaction was not significant, some significant differences between EI and EF …


Acremonium-Endophytes Of Perennial Ryegrass (Lolium Perenne) In France, C Ravel, C Astier, F Balfourier, G Charmet Jun 2024

Acremonium-Endophytes Of Perennial Ryegrass (Lolium Perenne) In France, C Ravel, C Astier, F Balfourier, G Charmet

IGC Proceedings (1977-2023)

Infection with endophytic fungi (Acremonium spp.) was detected in seeds of wild populations of perennial ryegrass (Lolium perenne) collected in France by private breeding companies and INRA. In total, 262 populations were examined and 70% contained Acremonium. It is worth noticing that most populations are endophyte infected but generally endophyte infection rates per population were low. Isolation of endophyte from each infected population is under progress and had already shown that the two taxonomic groups of endophytes of perennial ryegrass are present. This work lead to a view of the distribution of Acremonium endophytes from perennial …


Field Evaluation Of Soil Acidity Acidity Effects On The Growth Of Annual And Perennial Ryegrasses, N Miles Jun 2024

Field Evaluation Of Soil Acidity Acidity Effects On The Growth Of Annual And Perennial Ryegrasses, N Miles

IGC Proceedings (1977-2023)

Soil acidity limits pasture establishment and productivity in the moister eastern half of South Africa. Sound lime requirement guidelines based on soil test data are required. In the study reported here, lime responses of annual (Lolium multiflorum) and perennial (Lolium perenne) ryegrasses were evaluated in irrigated field trials located on acidic, highly weathered soils. Annual ryegrass (yield response to lime 27 to 32%) was found to be markedly more tolerant of soil acidity than perennial ryegrass (yield response 68%). Acid saturations of up to 20% had little impact on the yield of annual ryegrass, while yield …


Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma Apr 2024

Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma

IGC Proceedings (1977-2023)

Light partitioning in a grass-clover mixture was studied using a general competition model. The model assumes a fixed extinction coefficient (k) and no leaf dispersion. This was compared with modelling the effect of different k of both species over height as well as the effect of type of leaf dispersion. These new assumptions led to a better estimation of the light partitioning between both species. For grass the effect of variable k and leaf dispersion was similar and in both cases the total absorbed light was lower than under default conditions. For clover the new assumptions led to a higher …


Allocation Of Carbon-14 To Roots Of Different Ages In Perennial Ryegrass (Lolium Perenne L.), C Matthew, W D. Kemball Apr 2024

Allocation Of Carbon-14 To Roots Of Different Ages In Perennial Ryegrass (Lolium Perenne L.), C Matthew, W D. Kemball

IGC Proceedings (1977-2023)

The objective of this study was to provide information on how current photosynthate allocated to the root system in perennial ryegrass (Lolium perenne L.) is distributed among individual roots at differing nodal positions. Mature single ryegrass tillers were transplanted in September 1993 to glass house pots and three months later four of the plants were supplied with 14CO2. Individual roots from these radioactively-labeled plants were identified according to their nodal position on the tiller axis and amount of radiocarbon in each root quantified for root tip segments and for the remainder of the root axis. Similar plants were destructively …


Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely Mar 2024

Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely

IGC Proceedings (1977-2023)

Over four years, sowing perennial ryegrass (Lolium perenne) with a range of subterranean clover (“sub clover”, Trifolium subterraneum) cultivars was found to reduce the yield of clover per se by 31% and increase pasture yield by 11%. For one high-producing experimental variety, the presence of grass did not reduce clover yield (P<0.001). Clover yield in monoculture plots was poorly correlated with that measured in mixed swards (r = 0.44), but clover yield (± grass) was correlated with total herbage yield (r = 0.94). Clover seed yield was not reduced by the presence of grass. However, in year 2 - but not in the establishment year - grass reduced seed weight. Irrespective of grass treatment, the new late maturing cultivar, Leura outyielded the other commercial cultivars (P<0.05). Enfield and Enfield x Daliak crosses set the most seed and regenerated with a greater density than other cultivars (P<0.05) - apart from Leura. It was concluded that the winter-active, late maturing cultivar, Leura, will compete most successfully with perennial ryegrass.


Breeding Morphogenetic Traits To Match Genotypes To Their Utilization, L Hazard, M Betin, M Ghesquiere Mar 2024

Breeding Morphogenetic Traits To Match Genotypes To Their Utilization, L Hazard, M Betin, M Ghesquiere

IGC Proceedings (1977-2023)

A divergent selection for lamina length was done from natural populations of perennial ryegrass. Tested in a multi-site experiment in France, the short-leaved perennial ryegrass was more productive under simulated grazing and less productive under infrequent cutting than the long-leaved perennial ryegrass. Matching cultivars to their management is possible by selecting for morphogenetic traits. However, our results suggest the range of adaptation to different managements of perennial ryegrass cultivars could be extended by increasing their phenotypic plasticity.


Mitochondrial Genome Polymorphism In Lolium Perenne, Y Shimamoto, Y Tominaga, M Sato, T Mikami Mar 2024

Mitochondrial Genome Polymorphism In Lolium Perenne, Y Shimamoto, Y Tominaga, M Sato, T Mikami

IGC Proceedings (1977-2023)

The restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) of perennial ryegrass (Lolium perenne L.) were investigated to elucidate the genetic relatedness among the 128 cultivars including diploid and tetraploid. Many patterns of RFLPs were observed and allowed assigning of the cultivars into the main eight haplotypes of mitochondrial genome relatedness. The American cultivars were classified into haplotype I and VIII which were remote at the mitochondrial genome from each other, the European ones were distributed to all haplotypes and the tetraploid ones were mostly assigned into the haplotype V. The assessment of mtDNA RFLPs may be a …