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Articles 241 - 270 of 11958

Full-Text Articles in Physical Sciences and Mathematics

Accumulation Of Dry Matter, Protein And Total Available Carbohydrate In Berseem Under Different Cutting Regimes, P Martinello, G De Santis, A Iannucci, N Di Fonzo Aug 2024

Accumulation Of Dry Matter, Protein And Total Available Carbohydrate In Berseem Under Different Cutting Regimes, P Martinello, G De Santis, A Iannucci, N Di Fonzo

IGC Proceedings (1993-2023)

The effect of different cutting regimes on physiology and morphology of aerial parts and roots in 6 bcrseem (Trifolium alexadrium L.) genotypes was evaluated. Observations were carried out on individual plants at 4 stages of development: fourth and eighth internode elongation, early flowering and physiological seed maturity. The results showed that the genotypes were characterised by highest values of dry matter in the aerial and root parts at the early flowering stage. Variability among genotypes was observed.


Seasonal Growth Rhythms In Lucerne, C Poisson, G Genier, A Canal, P Guy, A Porcheron Aug 2024

Seasonal Growth Rhythms In Lucerne, C Poisson, G Genier, A Canal, P Guy, A Porcheron

IGC Proceedings (1993-2023)

The repartition of dry matter production of lilcerne (Medicago saliva) through the year is of great interest. A 3-year experiment began in 1990 to distinguish different rhythms of regrowth. Eighteen genotypes of very diverse geographic origins exhibiting great differences of winter dormancy were studied in a multisite experiment. Two different non-destructive methods were used to describe accurately leaf area index evolution: red far/red light ratio (660 nm/730 nm), and indirect measurement of LAI {LI-COR 2000); stem height and dry matter yield were regularly recorded. Important differences in summer and autumn behaviour leading to different sigmoid growth curves wece …


Inherent And Realized Potential Of Axillary Buds Of White Clover In Field Populations, P.C D. Newton, M.J M. Hay Aug 2024

Inherent And Realized Potential Of Axillary Buds Of White Clover In Field Populations, P.C D. Newton, M.J M. Hay

IGC Proceedings (1993-2023)

Fewer than 10% of while clover (Trifolium repens L.) axillary buds form established branches in grazed swards. In order to understand the mechanisms controlling his large loss of growth potential we have charted the potential fates a bud may meet. Each step in this flow chart offers the possibility for a loss of branching potential. We consider the factors that may be important in determining the fates of buds and highlight in particular the heavy losses of viable buds at a young age and propose that different factors may control branch initiation and branch establishment.


Prediction Of Plant Mortality Under Grazing- A Conceptual Approach, J J. Mott, G K. Mckeon, K A. Day Aug 2024

Prediction Of Plant Mortality Under Grazing- A Conceptual Approach, J J. Mott, G K. Mckeon, K A. Day

IGC Proceedings (1993-2023)

Based on the concept of biological thresholds, there is growing acceptance 0£ the importance o£ episodic events in the determination of rangeland condition trend. The variable rainfall occurring within Australian rangelands means that overstocking during droughts is a major cause of these Australian rangeland vegetation complexes exceeding these thresholds. Recently plant production models and simplistic estimates of the relationship between animal utilisation and plant mortality became available. Accurate estimates will be developed only with the incorporation of a sound mechanistic understanding of the relationship between utilisation of forage and plant mortality for different conditions of species and soils. Detailed studies …


Canopy Structure And Forage Production Of Lolium Rididum Gaudin As Influenced By The Frequency Of Defoliation, P P. Roggero, A Franca, M Sitzia, S Caredda Aug 2024

Canopy Structure And Forage Production Of Lolium Rididum Gaudin As Influenced By The Frequency Of Defoliation, P P. Roggero, A Franca, M Sitzia, S Caredda

IGC Proceedings (1993-2023)

An experiment was conducted in Sardinia to develop an appropriate rotational grazing management regime in spring for an ecotype of annual ryegrass (Lolium rigidum Gaudin). Three intermittent defoliation treatments were compared using sward surface height (10, 15 or 20 cm) to determine time of cutting. Forage dry matter yield, tiller population density, LAI, vertical distribution of plant tissues and other related characteristics were measured. Cutting when sward reached 10 cm resulted In significantly lower yields but a better canopy structure (denser sward, higher percentage of leaves in the bottom layers, higher leaf: sheath ratio) than the other treatments. The …


Physiological Response And Leaf Production Of Two C4 Grasses After Small Rainfall Events, A J. Norman, T L. Thurow, C A. Taylor Jr Aug 2024

Physiological Response And Leaf Production Of Two C4 Grasses After Small Rainfall Events, A J. Norman, T L. Thurow, C A. Taylor Jr

IGC Proceedings (1993-2023)

The response of plant water status and leaf production of sideoats grama (Bouteloua curtipendula Michx.) and curly mesquite (Hilaria belangeri Steud.) to application of 10 mm of water were studied in 6 continuous weighing lysimeters near Sonora, Texas, USA.: Transpiration, stomata! conductance, xylem water potentials and leaf production were measured foe both species. Soil water content was monitored in each lysimeter. The 10-mm simulated rainfall events improved plant water status regardless of prior soil water· content.' The transpiration rate for both species was similar. Stomata! conductance' of B. c1irtipe11d11/a responded faster after the simulated rainfall events. More favorable …


Effects Of Cutting Dates In Primary Growth, Water Soluble Carbohydrate Content And Nitrogen Fertilization On Regrowth Of Perennial Ryegrass, W Pohlmann, U Simon Aug 2024

Effects Of Cutting Dates In Primary Growth, Water Soluble Carbohydrate Content And Nitrogen Fertilization On Regrowth Of Perennial Ryegrass, W Pohlmann, U Simon

IGC Proceedings (1993-2023)

In a field experiment, an early• and a late-maturing cultivar of perennial ryegrass were cut during the primary growth in 6-weekly intervals starting when the early cultivar (Lolium perenne L.) reached stage of growth 31 (Simon & Park 1983, Proceedings XIV IGC), at 2 levels of nitrogen fertilisation. Dry mailer yield (DMY) in the regrowth was determined 4 weeks after defoliation in the primary growth. DMY in the regrowth decreased with delayed cutting in the primary growth. No significant correlation existed between the content of water soluble carbohydrates (WSC) in 1he stubble at the time of defoliation in the …


Effect Of Row Spacing And Sowing Rate On Establishment Of Lucerne Cv. Grasslands Oranga, M Askarian, J G. Hampton Aug 2024

Effect Of Row Spacing And Sowing Rate On Establishment Of Lucerne Cv. Grasslands Oranga, M Askarian, J G. Hampton

IGC Proceedings (1993-2023)

Studies on the effects of various row spacings and sowing rates on the establishment of autumn-sown lucerne (Medicago saliva L) cv. Grasslands Oranga were carried out in a split-plot experiment at Massey University Palmerston North, New Zealand. Seed was sown on 15 March 1991 at 1, 3, 6 and 12 kwha at row spacings of 15, 30, 45 and 60 cm. Seedling establishment increased as sowing rate and row spacing increased, but numbers of seedlings were not directly proportional to the number of seeds sown. The percentage establishment 6 months after sowing was significantly higher atthe lowest sowing rate. …


Searching For New Germplasm For The Year 2000 And Beyond, Rainer Schultze-Kraft, Warren M. Williams, John M. Keoghan Aug 2024

Searching For New Germplasm For The Year 2000 And Beyond, Rainer Schultze-Kraft, Warren M. Williams, John M. Keoghan

IGC Proceedings (1993-2023)

The likely germplasm needs for the next decades are discussed with major emphasis on tropical pastures, although many of the considerations apply also to temperate grasslands. The largest, and internationally most relevant, tropical-germplasm collections are held by CSIRO, CIAT and ILCA. Gerznplasm of <600 grass and <1500 legume species is available (with 6000-7000 and 26000-28000 accessions, respectively), representing 100-120 grass and 150-200 legume genera. Temperate germplasm collections are more numerous and hold larger numbers of accessions; they are, however, even more narrowly focused on very few genera (mainly four legume and eight grass genera). The numbers of species represented in the germplasm collections are only a fraction of considerably higher figures suggested in the literature as wild species with forage potential. Further collections to increase this fraction and to safeguard germplasm from genetic erosion and loss of biodiversity are warranted. International co-operation is suggested. Future germplasm needs are seen, in the tropics, mainly for low-input production systems on marginal, degraded lands and for agropastoral systems, and, in the temperate zone, for sustainable grasslands systems. Because of their dual­purpose characteristics legumes are expected to play a key role. It is suggested that the present collections might not contain a sufficiently broad base of germplasm with the required characteristics for the aforementioned production systems. Collection gaps can be identified only through thorough analyses of important genera and regions, based on a solid body of information that still needs to be assembled. A series of research topics is suggested to assist in future collection strategies, germplasm management and evaluation, and to create the basis for future breeding projects. However, expensive and long-term breeding programmes with tropical and many temperate forages are not encouraged for the near future unless the respective species and its natural variability are well enough known. The same applies to genetic manipulation via biotechnology. Implications arising from molecular biology are that new techniques are now available to improve understanding of genetic diversity and taxonomic relationships, and that the potential genetic resource now spans animals, micro-organisms and plants other than the target species. This wider genepool is also endangered and its conservation will rely on in situ preservation of the diverse ecosystems of which it is composed. The need of international support, co-operation and co-ordination regarding germplasm collection, related research and communication is emphasised. The creation of an JBPGR-sponsored, permanent, international working group on forages is suggested.


Establishing And Sharing Collections Of Valuable Global Resource, R Reid Aug 2024

Establishing And Sharing Collections Of Valuable Global Resource, R Reid

IGC Proceedings (1993-2023)

The conservation of forage plant genetic resources has attracted growing public and scientific interest in recent times. The number of genebanks has risen significantly with a concomitant increase in the total number of accessions. Competition for funds and some duplication of effort has led to an increasing need for co-operation between the curators if the full potential of the germplasm is to be realised. International organisations such as PAO, the mandated CGIAR Centres and IBPGR, have played a major role in establishing sustainable forage genetic resource programmes; and despite the restrictions of limited funding, have made some significant achievements in …


Plant List Of Accepted Nomenclature, Taxonomy And Symbols, J S. Peterson Aug 2024

Plant List Of Accepted Nomenclature, Taxonomy And Symbols, J S. Peterson

IGC Proceedings (1993-2023)

The Plant List of Accepted Nomenclature, Taxonomy & Symbols (PLANTS) is a dynamic database providing scientific and vernacular names, distributional, growth form, origin, symbols and bibliographic standardised botanical data to US federal agencies. PLANTS encompasses the vascular plant, moss, lichen and liverwort flora of North America, north of the Mexico border, including US states and territories.


The C3 Plants And C4 Plants Growing On Semi-Arid Steppes Of North-East China, Yin Lijuan, Zhu Tingcheng Aug 2024

The C3 Plants And C4 Plants Growing On Semi-Arid Steppes Of North-East China, Yin Lijuan, Zhu Tingcheng

IGC Proceedings (1993-2023)

The north-east steppe of China is semi-arid. Forty-seven species of C3 plants and 53 species of C4 plants were defined. The C pathway of the 42 forage species among the total l 00 species is firstly identified by determining the ratio between RuBPCase/PEPCase (RIP) and observing the Kranz leaf anatomy. The abundance of C4 plants decreases with decreasing precipitation and the intensity of soil sandesation, and increases with lower latitude and increased soil salinisation.


Indigenous Populations Of Lolium Perenne L. Identification, Evaluation And Conservation, G Spatz, A Oetmann, C Paul Aug 2024

Indigenous Populations Of Lolium Perenne L. Identification, Evaluation And Conservation, G Spatz, A Oetmann, C Paul

IGC Proceedings (1993-2023)

One hundred indigenous ryegrass populations were identified along 2 geographical gradients in Germany (west-east and north-south), Each population was sampled by collecting 180 tillers in 1991. The total 18 000 tillers were cultivated and will be examined as spaced plants (ex situ) in 1992 Nine selected populations were investigated in situ 1991. The results of the i11 situ investigations show high variability between and within the populations. The most valuable populations will be conserved as gene reserves within their environments (i11 situ). Promising material will in future be handed over to private breeders.


A Study On The Promising Ecotypes Of Secale Montaanum Guss., Bahram Peymani-Fard Aug 2024

A Study On The Promising Ecotypes Of Secale Montaanum Guss., Bahram Peymani-Fard

IGC Proceedings (1993-2023)

Secale montamum (mountain rye) has been identified as a well-adapted species for rehabilitation of the substeppic rangelands of Iran. Further investigation on the quality and quantity values of different ecotypes of this species was required. The main objective of this study was to determine phenological stages, herbage yield and protein percentage of the promising native ecotypes of Secale montanum. This research was conducted on 7 ecotypes in which early growth started in late April and heading occurred in late May. Comparison of the 4-year total herbage yield indicated significant differences among the ecotypes, Secale momtanum (10091), which was the previously …


Breeding Systems Of Several Vicia Species, J A. Mosjidis, X Zhang Aug 2024

Breeding Systems Of Several Vicia Species, J A. Mosjidis, X Zhang

IGC Proceedings (1993-2023)

Lack of or limited knowledge of 1he breeding systems of most of the Vicia speci1;s in the National Plant Germplasm System (USA) makes difficult the regeneration of the accessions as well as the maintenance of their genetic variability. Twenty-three accessions of V. arliculata, V. benghalensis, V. cracca, V. ervilia, V. lutea, V. narbonensis, V. pamionica and V. villosa were grown in the field in 1989 and 1990. Some plants were left uncovered outside"cages until fully mature while others were enclosed in cages when the first flower buds appeared. Plowers of the plants placed inside cages were subjected to the following …


Forage Quality Determinants Of Mott Elephantgrass And Pennisetum Hybrids, L E. Sollenberger, J E. Moore, J A. Flores-C, C J. Chaparro, B Macoon Aug 2024

Forage Quality Determinants Of Mott Elephantgrass And Pennisetum Hybrids, L E. Sollenberger, J E. Moore, J A. Flores-C, C J. Chaparro, B Macoon

IGC Proceedings (1993-2023)

Daily gains of cattle grazing Mott elephantgrass (MB; Pennisteum purpureIum Schum.) arc approximately twice those obtained on other warm-season perennial grasses grown in Florida, USA, but plant characteristics responsible for the high forage quality of MB have not been identified. Three experiments were conducted during 1987- 1991 to determine factors that explain the high forage quality of MB and to assess the quality potential of P. purpureum x P. glaucum (L.) [R.Br.J x clephantgrass hybrids. Higher organic matter (OM) digestibility and intake of MB than Pensacola bahiagrass (PB; Paspalum nonatum Flugge) were associated with a lesser percentage of sclercnchyma (1.6 …


Characterisation Of Us Collection Of Clover And Special Purpose Legume Germplasm, R R. Smith, K H. Quesenberry Aug 2024

Characterisation Of Us Collection Of Clover And Special Purpose Legume Germplasm, R R. Smith, K H. Quesenberry

IGC Proceedings (1993-2023)

Systematic collection of forage legume germplasm by the USA from the centers of origin was initiated in the 1890s. Since then over 11 000 accessions of clover and special-purpose legume species have been introduced into the US. These accessions are catalogued and maintained by the National Plant Germplasm System with working collections located at 4 locations in the US. Appropriate passport and evaluation data are available in the US Germplasm Resources Information Network (GRIN). The Clover and Special Purpose Legume Crop Advisory Commitlee is responsible for providing advice to the National Plant Germplasm System on the collection, mnintenance, evaluation and …


Determination Of Extractable And Bound Condensed Tannins In Forage Species, G B. Douglas, P Donkers, A G. Foote, T N. Barry Aug 2024

Determination Of Extractable And Bound Condensed Tannins In Forage Species, G B. Douglas, P Donkers, A G. Foote, T N. Barry

IGC Proceedings (1993-2023)

The levels of condensed tannins (CT) in 12 herbaceous species growing at 2 sites were determined using a recently modified butanol­HCL procedure. The method measured CT extractable in 70:30 acetone: water, and CT bound to protein and fibre, using ground, freeze-dried material. Total plant CT levels ranged from trace to 8% OM, with high concentrations (5-8% DM) being detected in 3 Dorycnium spp. and Lotus pedunculatus. Coronilla varia, Hedysarum coronarium and Lotus corniculatus had CT levels of 2-4% DM which may be appropriate for optimum nutritional value. CT content in ·n. rect11m, D. pe11taphyl/11m and L. pedunculatus was higher …


Herbaceous And Shrub Legumes Of Queensland: A Resource For Forage And Crop Improvement, J B. Hacker Aug 2024

Herbaceous And Shrub Legumes Of Queensland: A Resource For Forage And Crop Improvement, J B. Hacker

IGC Proceedings (1993-2023)

The potential for pasture or crop improvement of legume species native to Queensland, Australia is discussed. The most promising genera are Cajanus, Desmodlum, Glycine, Psoralea, Sesbanla and Vigna. Genera endemic to Australia offer little immediate scope for use in pasture or crop improvement. Some species, particularly in the genera Acacia, Crotalaria, Gastroloblum, Indigofera and Neptunia, can be toxic to livestock.


Morphological Characterization Of Brachiaria Germplasm, C B. Valle, B L. Maass, C B. Almeida, J.C G. Costa Aug 2024

Morphological Characterization Of Brachiaria Germplasm, C B. Valle, B L. Maass, C B. Almeida, J.C G. Costa

IGC Proceedings (1993-2023)

Brachiaria is a grass genus native to the tropical savannas of Africa. It encompasses about 90 species, a: few of which have gained economic importance owing to their adaptation to acid soils. A study was conducted at Campo Grande, Brazil and Quilichao, Colombia, using a large Brachiaria collection assembled by CIAT in east Africa. The objectives were to describe the diversity of this germplasm and to classify the accessions in clusters based on 7 morphological characters, by applying numerical taxonomy. Principal Component and Cluster Analyses were used. Wide variation was observed among the 386 accessions of 13 different species in …


Potential Of European Perennial Ryegrass Germplasm In Southern New Zealand, K H. Widdup, D L. Ryan Aug 2024

Potential Of European Perennial Ryegrass Germplasm In Southern New Zealand, K H. Widdup, D L. Ryan

IGC Proceedings (1993-2023)

86 cullivars of perennial ryegrass from The Netherlands, Germany, Denmark, France and Britain together with 9 New Zealand (NZ) cultivars were evaluated for agronomic potential in the cool, temperate southern region of NZ. Spaced plants of each cultivar were established in 1989 and screened for seasonal growth, moiphological features, head emergence, foliar diseases and endophyte presence. Principal Component Analysis (PCA) was used to order the relative performance of the cultivars taking all characters into consideration. A group containing 5 elite tetraploid and 10 diploid European cultivars showed potential for improving the summer feed quality of ryegrass. These cultivars contained densely …


A Landino White Clover Breeding Programme In Northern Italy, P Annicchiarico, E Piano Aug 2024

A Landino White Clover Breeding Programme In Northern Italy, P Annicchiarico, E Piano

IGC Proceedings (1993-2023)

Ladino wh ite clover (Trifolium repens L.) has traditionally been grown in pure stand rotational meadows throughout the Po Valley. Recent changes in the farming systems have drastically reduced the presence of this clover. Its rehabilitation depends on the cultivation of new, more productive cultivars in association with a grass. Thirty­two ecotypes including both farm land races and natural populations were collected and evaluated for dry mailer yield (OM) and seed yield, Significant variability was found among these materials for both traits. Compared with natural populations, land races yielded far more seed and as much DM . Some aspects …


Screening Trifolium Repens L. And T. Pratense L. Germplasm For Resistance To Cylindrocladium Crotalariae (Loos) Bell & Sobers, D S. Wofford, K H. Quesenberry Aug 2024

Screening Trifolium Repens L. And T. Pratense L. Germplasm For Resistance To Cylindrocladium Crotalariae (Loos) Bell & Sobers, D S. Wofford, K H. Quesenberry

IGC Proceedings (1993-2023)

Using a greenhouse screening technique, 200 plant introduction Jines of white clover (Trifolium repens L.) and red clover (T. pratense L.) germplasm were evaluated for resistance to cylindrocladium root rot incited by Cyl/11drocladium crotalariae (Loos) Bell & Sobers. In general, white clover germplasm had much higher levels of resistance than red clover. Over 60% of white clover introductions had 30% or greater resistance to cylindrocladium root rot, with 21 % of the lines possessing more than 40% resistant plants. No relationship was found between level of resistance and geographic origin for white clover. Red clover was more susceptible to …


Domestication Of The Australian Perennial Native Grass, Microlaena Stipoides, R.D B. Whalley, C.H A. Huxtable Aug 2024

Domestication Of The Australian Perennial Native Grass, Microlaena Stipoides, R.D B. Whalley, C.H A. Huxtable

IGC Proceedings (1993-2023)

Microlaena stipoides (Labill.) R.Br. is a year-long green perennial grass which is common throughout eastern and southern Australia. This species is a valuable component of pastures in parts of the New South Wales Tablelands because of its tolerance of acid soils and its ability to survive recent droughts.


Contribution Of Undomesticated Germplasm To Development Of Persistent, Grazing-Tolerant Lucerne, I Kaehne, E T. Kobelt, J A. Horsenell Aug 2024

Contribution Of Undomesticated Germplasm To Development Of Persistent, Grazing-Tolerant Lucerne, I Kaehne, E T. Kobelt, J A. Horsenell

IGC Proceedings (1993-2023)

The development of lucerne (Medicago saliva L.) germplasms which are tolerant to continuous grazing, adapted to dryland agriculture in the mediterranean zone and resistant to aphids, is described, Undomesticated lucerne accessions from 14 countries were crossed with winter-active cultivated lucerne accessions adapted to mediterranean climates to produce 4 S populations which were selected for tolerance to continuous intense grazing by sheep, The most tolerant populations were screened to develop germplasms resistant to spotted alfalfa aphid and blue-green aphid. The 72 populations that were developed from these germplasms by further selection for grazing tolerance and aphid resistance were tested for …


Multilocational Testing Of Grasses And Legumes In The Humid Tropics Of South America, G Keller-Grein, M C. Amezquita, G Lema, L H. Franco Aug 2024

Multilocational Testing Of Grasses And Legumes In The Humid Tropics Of South America, G Keller-Grein, M C. Amezquita, G Lema, L H. Franco

IGC Proceedings (1993-2023)

Adaptability of 5 grass and 13 legume accessions tested in 34 regional agronomic trials throughout the South American humid tropics was assessed by conducting a multilocational analysis on seasonal dry matter (DM) yield at 12 weeks regrowth. Among legumes, Stylosamhes guianensis CIAT 184 and 136, Desmodium ovaifolum CIAT 350, Zornia latifolla CIAT 728 and Centrosema macrocarpum CIAT 5065 were the highest yielding accessions in both rainfall periods and showed high adaptability to environmental conditions. Centrosema brasllianan CIAT 5234, C. pubescence CIAT 438 and Desmodiun heterophyifom CIAT 349 had low productivity and low adaptability. For grasses, Andropogon gayanus CIAT 621 outyielded …


Germplasm Collecting By Iger: The Future, N R. Sackville Hamilton, K H. Chorlton, I D. Thomas, M D. Hayward Aug 2024

Germplasm Collecting By Iger: The Future, N R. Sackville Hamilton, K H. Chorlton, I D. Thomas, M D. Hayward

IGC Proceedings (1993-2023)

This paper will present novel approaches being implemented or planned lo improve future collections for forage germplasm, and to deal with changing priorities, with particular reference to Lolium perenne. With a large number of accessions already in the gene bank and providing a wide range of genes for possible utilisation, future collections must be targeted ever more precisely, The principle object is to acquire novel genes not already present in the gene bank, to maximise the proportion of genes in the gene pool of L. perenne that is held in the gene bank. A subsidiary object, to support not …


Phenotypic Variability For Morphological And Agronomic Traits In Atriplex And Medicago Shrubs Accessions, M Pasquale, L Nicola Aug 2024

Phenotypic Variability For Morphological And Agronomic Traits In Atriplex And Medicago Shrubs Accessions, M Pasquale, L Nicola

IGC Proceedings (1993-2023)

The phenotypic variability for morphological and biological traits in 139 accessions of Atriplex hallmus L. and in 54 of Medicago arborea L. were evaluated. The accessions were collected from Meditenanean locations. Accessions of Atriplex were evaluated for 3 cuts (winter, spring and summer) and Medicago for 2 (winter and spring). The variability in both species was remarkable for all traits examined: In Alrlplex accessions it was related to the different origin of the materials (Sardinian and other Mediterranean environments),


Germplasm Collection, Evaluation And Selection Of Naturalized Medicago Polymorpha In The Mediterranean Zone Of Chile, C Ovalle, J Avendano, A Del Pozo, D Crespo Aug 2024

Germplasm Collection, Evaluation And Selection Of Naturalized Medicago Polymorpha In The Mediterranean Zone Of Chile, C Ovalle, J Avendano, A Del Pozo, D Crespo

IGC Proceedings (1993-2023)

An introduction and evaluation programme is described that thus far includes 53 accessions of the naturalised annual medic Medicago polymorplia L. collected along a 1000 km N-S gradient in central. Chile and subsequently grown together in a common environment· selection trial together with 5 accessions received from International Center for Agricultural Research in the Dry Areas (!CARDA). Major selection criteria include: precocious phenology, spineless pods and hardseededness, and tolerance to acid soils. Onset of flowering was 82-127 day_s, later flowering being closely correlated with higher latitudes. Soil pH was 5.3-7 .5 in collection sites, and phosphorus levels were > 10 ppm …


Alfalfa Energetic Value Improvement For Dairy Cows, M Ghesquiere, Jean Claude Emile, G Genier, P Guy Aug 2024

Alfalfa Energetic Value Improvement For Dairy Cows, M Ghesquiere, Jean Claude Emile, G Genier, P Guy

IGC Proceedings (1993-2023)

An experimental alfalfa (Medicago saliva L.) population whose in vitro and in vivo digestibilities are significantly higher than controls was offered to dairy cows in order to investigate its efficiency for· feeding high yielding dairy cattle. Three trials were conducted on first or second cut. Alfalfa was given ad lib. and as fresh forage. The improved digestibility was confirmed. The experimental type was ingested more by cows despite a lower dry matter content and allowed higher milk production. This result shows a real genetic variability for energetic value in alfalfa.