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Articles 271 - 300 of 16610
Full-Text Articles in Physical Sciences and Mathematics
Production Of Dryland Lucerne In The Western And Southern Cape Regions Of South Africa, J M. Van Heerden
Production Of Dryland Lucerne In The Western And Southern Cape Regions Of South Africa, J M. Van Heerden
IGC Proceedings (1993-2023)
Cutting trials were conducted with lucerne (Medicago sativa) cv. S A Standard under dryland conditions over a period of 8 (1982 to 1989) years at 2 sites, one each in the western (Elsenburg) and southern (Tygerhoek) Cape. The sites differed in soil type and rainfall distribution. Replicated plots were harvested at 3 set frequencies (4·, 6- and 8- weekly). Production was lowest during summer and highest in late spring and increased with decreased harvesting frequency at both sites. These data were used to derive equations for the extrapolation of the seasonal yield. Inputs into the model 11cc average …
Graze Model: Importance Of Simulating Conceptual Grazing Areas Within A Paddock, Otto J. Loewer, L D. Parsch, H D. Scott, C P. West, A L. Goetsch
Graze Model: Importance Of Simulating Conceptual Grazing Areas Within A Paddock, Otto J. Loewer, L D. Parsch, H D. Scott, C P. West, A L. Goetsch
IGC Proceedings (1993-2023)
The selective grazing logic within the computer simulation model GRAZE was tested to determine if predicted ·results differed appreciably from situations ·where non-selective grazing logic· was used. Results indicated that predictions would_ differ somewhat." The main cause of the differences was determined to be the simulated levels of plant dry matter availability, which were considerably higher when non-selective· grazing was used.
Development Of An Expert System For New Zealand Seasonal-Supply Dairy Farmers, D I. Gray, G A. Lynch, E G. Todd, J C. Lockhart, W J. Parker
Development Of An Expert System For New Zealand Seasonal-Supply Dairy Farmers, D I. Gray, G A. Lynch, E G. Todd, J C. Lockhart, W J. Parker
IGC Proceedings (1993-2023)
The mechod for developing an expert system for the drying-off decision on seasonal-supply dairy farms is described. The decision-making process ' of 4 expert seasonal-supply dairy farmers and the consultancy process used by 2 New Zealand Dairy Board Consulting Officers were identified in a series e>f interviews. This information ,was used to develop 2 models; one of expertise and the other of user requirements. These models form the basis of an expert system to improve the decision-making ability of. New Zealand seasonal-supply dairy farmers.
Rehabilitation On Public Rangelands In Idaho, Usa: A Change In Emphasis From Grass Monocultures, Mike Pellant, Stephen B. Monsen
Rehabilitation On Public Rangelands In Idaho, Usa: A Change In Emphasis From Grass Monocultures, Mike Pellant, Stephen B. Monsen
IGC Proceedings (1993-2023)
Since the 1940s the Bureau of Land Management has reseeded 485 830 ha of public rangelands in southern Idaho. Introduced wheatgrasses were seeded on most rehabilitation projects, often resulting in monoculture plant communities. Introduced wheatgrasses were relatively inexpensive to seed, established well, excluded weedy annuals and provided additional livestock forage. Concern about extensive shrubland losses after wildfires prompted BLM managers to begin reseeding native shrubs in the early 1980s. Use of different herbaceous plants on rehabilitation projects is increasing. Seed mixtures now include up to 10 species (grass, forb and shrubs) that, when established, meet multiple use resource objectives.
Micro-Computer Version Of The Database On Feed Commodities Derived From Pastures And Green Crops, H T. Ostrowski-Meissner
Micro-Computer Version Of The Database On Feed Commodities Derived From Pastures And Green Crops, H T. Ostrowski-Meissner
IGC Proceedings (1993-2023)
The subunit of the national feed database devoted specifically to feeds derived from grasslands and green crops is presented. This collection of chemical and nutritional data is the result of 20 years of data collection from analyses conducted from 62 laboratories Australia-wide, The data entries are classified according to each Australian state and laboratory which provided the analytical and nutritional characteristics of fodder. Each entry is classified according to the International Feed Numbering (IFN) system as maintained by the International Network of Feed Information Centres (INFIC), The data in the collection as presented in the paper are an integral part …
A Computer Model For Determining When To Start Spring Grazing, Dennis R. Buckmaster, Warren J. Parker
A Computer Model For Determining When To Start Spring Grazing, Dennis R. Buckmaster, Warren J. Parker
IGC Proceedings (1993-2023)
A simple computer model is presented for determining the earliest grazing date after winter freezing. The model also illustrates principles of rotational grazing management and projects when forage should be conserved during the spring. Inputs to the model include initial herbage cover, herbage growth rate, herbage quality, a post•grazing residual dry matter target, a harvest set•aside threshold, and a description of the grazing animals.
Comparison Of Methods For Assessing Productivity Of Native Pastures In Queensland, K A. Day, G M. Mckeon, D M. Orr
Comparison Of Methods For Assessing Productivity Of Native Pastures In Queensland, K A. Day, G M. Mckeon, D M. Orr
IGC Proceedings (1993-2023)
The relationship between seasonal climatic conditions and observed seasonal pasture growth was examined for 3 native pasture sites in south-east Queensland for periods of up to 5 years. Nine indices of seasonal climatic conditions were considered. Across sites, between year differences in observed growth were best accounted for by the average daily ratio of calculated transpiration and vapour pressure deficit, This index accounted for 83% of the between year variation in observed growl h.
Application Of Neural Networks To The Extraction Of Various Types Of Grasslands In Japan Using Landsat Thematic Mapper Data, Mikinori Tsuiki, Shigeo Takahashi, Toshiki Oku
Application Of Neural Networks To The Extraction Of Various Types Of Grasslands In Japan Using Landsat Thematic Mapper Data, Mikinori Tsuiki, Shigeo Takahashi, Toshiki Oku
IGC Proceedings (1993-2023)
A neural network was applied to the extraction of various types of grasslands using Landsat Thematic Mapper (TM) data. Training fields contained 12 classes (water, paddy field, farmland, sands and rocks, urban area, coniferous forest, deciduous forest, golf course, Sasatype grassland, Miscanthus type grassland, meadow before culling and meadow after cutting). Classification performance using the neural network was 99.4%, which was 2.4% higher than that obtained using the maximum likelihood method. For all types of grasslands, classification performance was 99.8%. The results of the classification area obtained using the neural network and the maximum likelihood method resembled each other. …
Use Of A Simple Model Of Continuous And Rotational Grazing To Compare Herbage Consumption, Simon J.R Woodward, G `C Wake, D G. Mccall, A B. Pleasants
Use Of A Simple Model Of Continuous And Rotational Grazing To Compare Herbage Consumption, Simon J.R Woodward, G `C Wake, D G. Mccall, A B. Pleasants
IGC Proceedings (1993-2023)
A simple mathematical model (a linear dynamical system) was constructed to predict herbage consumption by grazing animals. This model was used to compare 3 grazing methods over a range of stocking rates at low pasture mass. The grazing methods compared were: continuous grazing (CTS), rotational grazing with equal time intervals (BQ), and rotational grazing where the time of shift was optimal for maximising intake (OPT). The rotational methods were the simplest possible, the land being subdivided into 2 fields, each of which was grazed once. The order of grazing the fields was also considered. The model predicts (I) that at …
Pasture Plant Identification In The Western Queensland Arid Zone, J A. Milson, I F. Beale, J A. Reynolds, J J. Bushwell, D Phelps
Pasture Plant Identification In The Western Queensland Arid Zone, J A. Milson, I F. Beale, J A. Reynolds, J J. Bushwell, D Phelps
IGC Proceedings (1993-2023)
Since plant species composition is an important indicator of the health or condition of pastures and therefore the land, a first step for graziers interested in conserving the total range resource is to understand vegetation species and thus be able to identify them and to recognise species changes. This project is aimed at producing and distributing colour leaflets of the major native and problem plant species (including woody weeds) in the four major community types in western Queensland. The number of colour leaflels for the series totals 60. The number of species represented is about 230. These leaflets are dislributed …
Farm Monitoring, A Way To Improve Performance On Sheep And Beef Farms, R W. Webby, G W. Sheath
Farm Monitoring, A Way To Improve Performance On Sheep And Beef Farms, R W. Webby, G W. Sheath
IGC Proceedings (1993-2023)
A programme that centres on monitoring the performance of sheep and beef farms is being used to encourage farmers to make decisions based on objective measurements, Monitor farmers are supported by their farming peers in groups that include extension and science personnel. Key biological performance indicators such as animal numbers, weights; weight gains, pasture production; and financial returns from meat and wool are monitored. Farmers are encouraged to be in a position to use this information and identify opportunities. Processors of sheep and beef products are demanding the production of livestock to tighter specifications. Close monitoring by farmers will be …
Use Of A Model To Investigate The Profitability Of Fertilizer Application, T.J M. Johnston, D G. Mccall, P R. Marshall
Use Of A Model To Investigate The Profitability Of Fertilizer Application, T.J M. Johnston, D G. Mccall, P R. Marshall
IGC Proceedings (1993-2023)
Use of a model to investigate the payback to alternative phosphate (P) fertiliser programmes is described. Input for the model is fertiliser history (kg P/ho/year) over 5-15 years. A site fertility index is established by summing discounted P applications. The index is related to relative pasture yield (annual yield/non P limited yield) for a soil type. The economics of P use are evaluated by scaling current gross margin/ha for changes in relative pasture yield and subtracting fertiliser costs. The model provides the decision maker with yearly cashflow information and a I 0-year net present value (NPV) analysis of the relative …
Effects Of Cutting Management On Herbage Production And Tiller Population In Smooth Bromegrass (Bromus Inermis Leyss), J X. Xia, J Hodgson, A.C P. Chu, P Wang, F Y. Liu
Effects Of Cutting Management On Herbage Production And Tiller Population In Smooth Bromegrass (Bromus Inermis Leyss), J X. Xia, J Hodgson, A.C P. Chu, P Wang, F Y. Liu
IGC Proceedings (1993-2023)
This paper reports the results of an experiment with smooth bromegrass (Bromus inermis Leyss) under cutting management at Beijing Agricultural University, China from June-October 1989. The main treatments were cutting intervals (l month v. 2 months) and cutting height (10 cm v. 30 cm) with 2 additional treatments (uncut control, and delayed first cut) and 4 replications. Frequent cutting decreased tiller population density, herbage accumulation and underground biomass. Tiller populations were greater under lax than hard cutting, though closer cutting resulted in greater green herbage accumulation. Delaying cutting until flowering was completed resulted in a subsequent depression in herbage …
Relative Productivity And Persistense Of White Clover Cultivars Under Cutting Or Continuous Stocking By Sheep, D A. Davies, M Fothergill
Relative Productivity And Persistense Of White Clover Cultivars Under Cutting Or Continuous Stocking By Sheep, D A. Davies, M Fothergill
IGC Proceedings (1993-2023)
Perennial ryegrass-white clover (Lolium perenne-Trlfollium repens) swards of 3 clover cultivars were studied at a lowland (30 m) and upland (340 m) site in mid Wales over 3 years (1989-91). Lamb production from small-leaved Aberystwyth S 184 at 1021 kg/ha was 25% and 1191, more than from small-leaved Ac3351 and medium-leaved Grasslands Huia respectively. The relative lamb output from Huia was poorer at the upland location. Clover production, survival and morphology under a number of cutting heights and frequencies were different from those in the continuously stocked pastures. Cutting every 10 days at 2-3 cm resulted in poor clover and …
Morphological Changes In Three Clover (Trifolium Repens L.) Cultivars Under Continuous Stocking, M Fothergill, D A. Davies
Morphological Changes In Three Clover (Trifolium Repens L.) Cultivars Under Continuous Stocking, M Fothergill, D A. Davies
IGC Proceedings (1993-2023)
Individual plant morphology of 3 white clover (Trifolium repens L.) cultivars was studied during 1990 and 1991. Seasonal shifts were demonstrated by all cultivars towards a higher proportion of less complex plants from winter to mid summer. Over the latter half of the year the population tended lo return towards its original distribution. Seasonal fluctuations in stolon dry weight/plant and root number/plant were also identified, with the small-leaved Ac3351 maintaining a greater stolon OW/plant than Aberystwyth S184 and Grasslands Huia during 1990. Ac3351 and S184 also maintained a larger root number/plant over this period. However, no significant differences were detected …
Response To Defoliation Of Tall Fescue, H Tavakoli, J Hodgson, P D. Kemp
Response To Defoliation Of Tall Fescue, H Tavakoli, J Hodgson, P D. Kemp
IGC Proceedings (1993-2023)
An experiment studying the behaviour of toll fescue (Fesutca anrundinacea Schreb,) was conducted under steady stale grazing on a sward dominated by this plant. The swards were grazed lo maintain a surface height of 30-40 mm (H), 50-60 mm (M) and 90-100 mm (L). These treatments were applied on swards with and without white clover (Trifolium repens L.) from November 1990 to April 1991. Results showed that leaf growth decreased as the severity of grazing increased. Tiller number was less under H grazing than under M or L grazing, but tiller size remained constant over time in this …
Carbon Isotope Discrimination And Productivity Of Yellow-Flowered Falcata Alfalfa Clonesj, J A. Morgan, D R. Lecain, C E. Townsend
Carbon Isotope Discrimination And Productivity Of Yellow-Flowered Falcata Alfalfa Clonesj, J A. Morgan, D R. Lecain, C E. Townsend
IGC Proceedings (1993-2023)
Although genetic variation for water•use efficiency has been identified in a number of plant species, progress to genetically increase this trait has been limited, largely owing to the difficulty in evaluating numerous genotypes. Eleven clones of yellow-flowered, falcata-type alfalfa (Medicago saliva L. ssp. falcata (L.) Arcangeli} were grown in the greenhouse under 2 watering regimes, and in space•planted field plots for 2 years. Clonal variation was found in all 4 environments for plant yield and shoot carbon isotope discrimination (A), a trait believed to estimate plant water use efficiency. Generally nonsignificant correlations between A and forage yield suggest that …
Adaptation Of Sainfoin Cultivars And Lucerne To Water Stress, S R. Mir Hosseini, P D. Kemp, D J. Barker, J Hodgson
Adaptation Of Sainfoin Cultivars And Lucerne To Water Stress, S R. Mir Hosseini, P D. Kemp, D J. Barker, J Hodgson
IGC Proceedings (1993-2023)
Sainfoin ( Onobrychis viciifolia Scop.) is of particular interest as a pasture crop because it is a productive legume in dry areas but does not induce bloat in ruminant animals. In this study 3·sainfoin cultivars (Fakir, Melrose and 035) and l lucerne (Medicago saliva L.) cultivar Grasslands Oranga were compared during a drying phase when water was withheld once; flowering began. A randomised complete block design with 4 replicates' was used. Transpiration rate (Tr) declined as volumetric soil water content (VSWC) was reduced. Stomata! resistance (Rs) increased and relative ivater content (RWC) decreased when VSWC decreased. Critical VSWC for …
Phytochrome Control Of Assimilate Partitioning In White Clover, Ch Robin, C Varlet-Grancher, F Gastal, A Guckert
Phytochrome Control Of Assimilate Partitioning In White Clover, Ch Robin, C Varlet-Grancher, F Gastal, A Guckert
IGC Proceedings (1993-2023)
Experiments were conducted in controlled conditions to examine the influences of phytochrome on assimilate partitioning between stolons and branches and to determine the effects on plant moq>hogcncsis in white clover (Trifolium repens L.). Far-red (FR) irradiated plants partitioned more 14C-assimilates to petioles of both the main stolon and branches and less to the nodulated COOis than did control plants. Results clearly demonstrated that FR-irradiated plants developed longer petioles and long internodes. Moreover, the branching rate decreased, which induced a lower portion of dry weight allocated to branches. However, the sink strength of the branches which were developing remained …
Influence Of Rooting On Stolon Branching In White Clover, M Jones, N R. Sackville Hamilton
Influence Of Rooting On Stolon Branching In White Clover, M Jones, N R. Sackville Hamilton
IGC Proceedings (1993-2023)
The relationship between rooting and branching in stolons of white clover (Trifolium repens L.) was investigated in a field experiment, Half of a group of stolons was allowed to develop roots naturally, while for the other half root establishment was prevented by severing young roots before they made contact with the soil. Prevention of root establishment did not affect the numbers of branches which developed on nodes produced during the experiment, and it stimulated of branching on nodes which were already present. This result was unexpected on the basis of earlier observations of stolon growth and suggests that the …
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
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
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
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
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
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
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
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
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
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
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 …