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Full-Text Articles in Life Sciences
Conservation Of Grass Collections At The Western Regional Plant Introduction Station, V L. Bradley, R C. Johnson
Conservation Of Grass Collections At The Western Regional Plant Introduction Station, V L. Bradley, R C. Johnson
IGC Proceedings (1997-2023)
Germplasm managers at the Western Regional Plant Introduction Station (WRPIS) have focused on improving seed regeneration in forage and turf grass species through studies of diversity maintenance, using isozyme markers in annual ryegrass (Lolium multiflorum Lam.) and through studies of pollen isolation, using strains of dominant pubescent and recessive glabrous smooth bromegrass (Bromus inermis Leyss.). Balanced samples of annual ryegrass (an equal number of seeds per plant) from field plots were best for maintaining allelic frequencies, but genetic diversity (heterozygosity and allelic richness) was maintained nearly as well in bulk samples (seeds proportionally assembled according to seeds per …
Ecogeographic Assessment Of Mediterranean Environments For Targeting Legume Collections, S J. Bennett
Ecogeographic Assessment Of Mediterranean Environments For Targeting Legume Collections, S J. Bennett
IGC Proceedings (1997-2023)
The mediterranean area is the centre of diversity for many of the legume species of agricultural importance and their wild relatives. Ecogeographical assessments are a method of determining the areas within the mediterranean that are homologous with a particular area within southern Australia. Using Geographical Information Systems the distribution of legume species are mapped and related to other climatic and edaphic factors. Using this data it is possible to show which areas of the mediterranean have been well collected and where the edaphic requirements of a species can be found and therefore where to collect it. The detail of an …
Grazing Effects On Soil Seed Banks: A Global Synthesis, Shi Yafei
Grazing Effects On Soil Seed Banks: A Global Synthesis, Shi Yafei
IGC Proceedings (1997-2023)
Livestock grazing is a major disturbance affecting plant diversity and abundance in terrestrial ecosystems. The intermediate disturbance hypothesis (IDH) predicts that moderate-intensity grazing should produce the highest species diversity, while the Milchunas-Sala-Lauenroth (MSL) model posits that the IDH is valid only for mesic areas. However, it remains unclear how grazing affects soil seed bank and whether or not the IDH or MSL models are valid for soil seed bank communities. Here, we presented a global meta-analysis synthesizing 483 observations: we found that grazing had a negative effect on soil seed bank abundance, but did not alter seed bank richness. Further …
Beyond The Boom: Integrated Approaches To Managing Weeds And Brush, M. L. Treadwell, D. Burson
Beyond The Boom: Integrated Approaches To Managing Weeds And Brush, M. L. Treadwell, D. Burson
IGC Proceedings (1997-2023)
William Bray stated in his 1904 report, The Timber of the Edwards Plateau of Texas, "This struggle of the timberlands to capture the grasslands is an old warfare....it spreads like infection.” This trend is true today and especially pronounced in the Great Plains, where only 1/4 of the Great Plains’ original grasslands remains intact. Species like honey mesquite, honey locust, black locust, sumac, dogwood, post oak, winged elm, Siberian elm, salt cedar, huisache, Eastern redcedar, Ashe and redberry juniper, pricklypear, sericea lespedeza, and many other species represent alarming rates of spread and rapid establishment throughout Great Plains grasslands. Although, these …
Grazing Effects On Soil Seed Banks: A Global Synthesis, Shi Yafei
Grazing Effects On Soil Seed Banks: A Global Synthesis, Shi Yafei
IGC Proceedings (1997-2023)
Livestock grazing is a major disturbance affecting plant diversity and abundance in terrestrial ecosystems. The intermediate disturbance hypothesis (IDH) predicts that moderate-intensity grazing should produce the highest species diversity, while the Milchunas-Sala-Lauenroth (MSL) model posits that the IDH is valid only for mesic areas. However, it remains unclear how grazing affects soil seed bank and whether or not the IDH or MSL models are valid for soil seed bank communities. Here, we presented a global meta-analysis synthesizing 483 observations: we found that grazing had a negative effect on soil seed bank abundance, but did not alter seed bank richness. Further …
Grass Diversity And Pasture Quality Baseline Assessement In Central Madagascar, O. P. Nanjarisoa, L. Randriamanalina, Wayne F. Truter, M. T. Rajaonah, C. E. R. Lehmann, C. Birkinshaw, L. Rakotonirina, D. Miarinjanahary, N. L. Raharinirina, M. S. Vorontsova
Grass Diversity And Pasture Quality Baseline Assessement In Central Madagascar, O. P. Nanjarisoa, L. Randriamanalina, Wayne F. Truter, M. T. Rajaonah, C. E. R. Lehmann, C. Birkinshaw, L. Rakotonirina, D. Miarinjanahary, N. L. Raharinirina, M. S. Vorontsova
IGC Proceedings (1997-2023)
Poaceae family contributes to Madagascar’s biodiversity hotspot with 217 of 541 grass species endemic to the island, although their forage value is unknown, at least in the scientific literature. Our research aims 1) to describe the diversity of native and endemic grasses thereby recognising the role of grass species diversity in forage and ecosystem management and 2) to provide new knowledge about pasture management based on the relationship between grazing capacity and productivity within experimental pastureland plots under different fire and grazing treatments. Our study seeks to provide information to inform improvements in livestock nutrition via grazing management of natural …
Tiller Demography Within Synthetic Grass Populations, K. J. Moore, C. Córdova
Tiller Demography Within Synthetic Grass Populations, K. J. Moore, C. Córdova
IGC Proceedings (1997-2023)
Like other populations of biological organisms, the collective aging structure of a population of grass tillers has meaning and consequences far beyond the development of an individual within it. Using various methods, it is possible to assign numerical indices to tiller development so that it can be described numerically. By sampling a population of tillers and assigning a numerical index to each, the average stage of tillers within a population can be calculated and a repeatable assessment of its development determined. The average or mean stage count (MSC) of tiller development is commonly calculated and used to compare the development …
Diversity And Adaptation Of Perennial Plants From North Africa: Legumes And Grasses, Aissa Abdelguerfi, M. Laouar, K. Abbas, M. M'Hammedi Bouzina
Diversity And Adaptation Of Perennial Plants From North Africa: Legumes And Grasses, Aissa Abdelguerfi, M. Laouar, K. Abbas, M. M'Hammedi Bouzina
IGC Proceedings (1997-2023)
A variety of climates, soil types and reliefs characterise North Africa (Algeria, Morocco, and Tunisia). These natural conditions have produced a large diversity of environments, landscapes, plant formations and flora. Several factors have contributed to the spread of a wide floristic variety: the influence of the Mediterranean in the north and in the north-east, the Atlantic in the west, and the Sahara in the south, as well as the presence of mountain ranges, particularly the Rif, the Tell Atlas, the Sahara Atlas, the Middle Atlas, the High Atlas, and the Anti-Atlas. This diversity of landscapes, environments and ecosystems has generated …
Plant Functional Types And Grazing Management In Mediterranean Grassland: An 11-Year Synthesis, Marcelo Sternberg, Zalmen Henkin, Avi Perevolotsky, M. Gutman, Eugene D. Ungar
Plant Functional Types And Grazing Management In Mediterranean Grassland: An 11-Year Synthesis, Marcelo Sternberg, Zalmen Henkin, Avi Perevolotsky, M. Gutman, Eugene D. Ungar
IGC Proceedings (1997-2023)
Mediterranean ecosystems have high seasonality in resource availability, high year-to-year rainfall variability, many annual plants in the forage and a long history of grazing and disturbance. These facts, and results of previous studies (Sternberg et al., 2000) suggested that stocking rates could be increased above those of traditional grazing. However, the long-term effects of intensive grazing on the vegetation were not fully known. This study aimed to evaluate the responses of plant functional types (PFT) and community structure to different regimes of cattle grazing in Mediterranean grassland, particularly at high stocking rates.
The Effect Of Grazing On Rare And Common Grasses And Forbs In The Mediterranean Coastal Desert Of Egypt, A. El-Keblawy, A. Ramadan
The Effect Of Grazing On Rare And Common Grasses And Forbs In The Mediterranean Coastal Desert Of Egypt, A. El-Keblawy, A. Ramadan
IGC Proceedings (1997-2023)
Large parts of the rangelands in the Arab countries are either overgrazed or gradually deteriorating due to large numbers of livestock and unrestricted grazing (Assaeed, 1997). Protection of vegetation against grazing in desert environments has been suggested as a feasible approach to halting land degradation and rehabilitating rangelands (El-Keblawy, 2003). However, little is known about the response of different plant life forms and life cycles to grazing. The objectives of this study were to address this point and to test the response of rare and common forbs and grasses to protection against grazing.
The Relationship Between Species Diversity And Productivity Of Cool-Season Grassland, S. E. Florine, Kenneth J. Moore, Steven L. Fales, R. L. Hintz
The Relationship Between Species Diversity And Productivity Of Cool-Season Grassland, S. E. Florine, Kenneth J. Moore, Steven L. Fales, R. L. Hintz
IGC Proceedings (1997-2023)
Iowa grasslands consist mainly of introduced cool-season grasses and forbs. Many of these species are well adapted and have become naturalised. Most of these grasslands are located on marginal sites with heterogeneous soils and topography. Consequently, there is significant variation in the botanical composition and biomass productivity within and across grassland sites. This experiment aimed to evaluate the botanical composition and biomass productivity of representative grasslands and to determine if there was a relationship between grassland species diversity and biomass production across sites.
Operating Systems Of The Meadows In Semi-Arid Region Of Algeria, K. Abbas, M. Abdelguerfi-Laouar, Aissa Abdelguerfi, T. Madani, A. Mebarkia
Operating Systems Of The Meadows In Semi-Arid Region Of Algeria, K. Abbas, M. Abdelguerfi-Laouar, Aissa Abdelguerfi, T. Madani, A. Mebarkia
IGC Proceedings (1997-2023)
Permanent meadows are the base of the fodder resources and also provide environmental services (MAP France, 2002). The function of fodder production is no longer solely to ensure bulk agricultural production. It must also allow the development of livestock products of good quality, contribute to environmental protection, the quality of the landscape and ensure a viable economic activity in the rural areas. These areas have decreased greatly (from 1 million ha at the beginning of the century (Lapeyronie, 1982) to less than 300,000 ha in 2000), in particular in the semi-arid zones at high altitude; however they contribute very effectively …
Pasture Condition Scoring, James B. Cropper
Pasture Condition Scoring, James B. Cropper
IGC Proceedings (1997-2023)
A pasture condition score sheet has been developed for use in the United States. It has rating criteria for key indicators that are used to ascertain if some areas of pasture management could be improved. It can also help evaluate what is causing less than desirable pasture conditions. Pasture condition scoring involves the visual and tactual evaluation of ten indicators that rate a pasture's overall condition. The ten indicators are: percent desirable plants, plant cover, plant diversity, plant residue, plant vigor, percent legume, uniformity of use, livestock concentration areas, soil compaction, and erosion (sheet and rill, gully, streambank and shoreline, …
Does Aflp Diversity Reflect Consanguinity Within Meadow Fescue Breeding Material?, B. Boller, R. Kölliker
Does Aflp Diversity Reflect Consanguinity Within Meadow Fescue Breeding Material?, B. Boller, R. Kölliker
IGC Proceedings (1997-2023)
Cultivars of perennial grass species are usually synthetics with a limited number of constituent parental clones, prone to inbreeding depression. Plant breeders aim at a balance between intensity of selection and maintenance of genetic diversity when making their choice of parent clones in an intuitive way, aided by fragmentary pedigree information. Molecular markers offer new opportunities for assessing genetic diversity among selected plants. The objective of the investigation presented here is to check if the genetic distance as measured by AFLP polymorphisms reflects consanguinity among Festuca pratensis individuals from our breeding programme.
Genetic Diversity And Heterosis In Perennial Ryegrass, U. K. Posselt
Genetic Diversity And Heterosis In Perennial Ryegrass, U. K. Posselt
IGC Proceedings (1997-2023)
Plant breeders are concerned with the diversity among and within breeding populations, because it largely determines the future prospects of success in breeding programs. DNA markers provide a powerful tool for the assessment of genetic diversity. The relationship between genetic diversity and heterosis has been investigated in several species (Melchinger, 1999). In hybrid breeding programs divergent genepools have been established in the past, according to heterotic patterns based on testcross information. In the last decade it has been shown, that new breeding materials can be assigned to already existing gene pools using molecular markers. The phenomenon of heterosis has been …
Genetic And Phenotypic Diversity Of Swiss Red Clover Landraces, D. Herrmann, B. Boller, F. Widmer, R. Kölliker
Genetic And Phenotypic Diversity Of Swiss Red Clover Landraces, D. Herrmann, B. Boller, F. Widmer, R. Kölliker
IGC Proceedings (1997-2023)
Mattenklee landraces are persistent and locally adapted Swiss red clover populations. About 100 populations are preserved and may represent a significant yet poorly characterised genetic resource for temperate regions. Genetic characterisation is important in order to improve cultivars, manage genetic resources and to maintain or restore biodiversity. The objectives of this study were to analyse genetic diversity, investigate potential ancestry and to elucidate the congruence of phenotypic and genetic structure of Mattenklee landraces.
Genetic Diversity In Colonial Bentgrass (Agrostis Capillaris L.) Revealed By Ecori/Msei And Psti/Msei Aflp Markers, H. Zhao, S. Bughrara
Genetic Diversity In Colonial Bentgrass (Agrostis Capillaris L.) Revealed By Ecori/Msei And Psti/Msei Aflp Markers, H. Zhao, S. Bughrara
IGC Proceedings (1997-2023)
Colonial bentgrass species (Agrostis capillaris L.) is a potential genetic resource for the improvement of other bentgrass species (Agrostis spp.) with regard to resistance to environmental stresses and diseases. Transferring resistance from colonial to other bentgrass species is a promising goal in turfgrass breeding programs (Belanger, 2003). Assessment of genetic diversity among accessions of colonial bentgrass species will contribute to eliminate undesirable duplications in the germplasm collection and increase the efficiency of research efforts. It will allow researcher to select diverse resistance genes from different sources to incorporate and pyramid these resistance genes into creeping or other bentgrass …
Species Richness, Species Identity And Ecosystem Function In Managed Temperate Grasslands, S. C. Goslee, M. A. Sanderson, K. Soder
Species Richness, Species Identity And Ecosystem Function In Managed Temperate Grasslands, S. C. Goslee, M. A. Sanderson, K. Soder
IGC Proceedings (1997-2023)
Manipulation of plant species diversity may provide a way to improve the ecosystem functioning of managed systems by increasing productivity and suppressing weedy species. As yet, the functional role of species richness is not well-enough understood to enable practical application. We investigated the effects of differing species richness on community stability and invasion resistance in a grazed temperate grassland.
Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons, K. Soder, M. A. Sanderson, J. L. Stack, L. Muller
Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons, K. Soder, M. A. Sanderson, J. L. Stack, L. Muller
IGC Proceedings (1997-2023)
Voluntary intake and stocking rate are key determinants of animal performance on pasture. Greater plant diversity in grassland plant communities has been linked to increased primary production, greater stability in response to disturbance, and reduced weed pressure. Thus, increasing plant diversity may be one approach to improving animal productivity. An experiment was conducted to determine the effects of forage diversity on intake and milk production of lactating dairy cows over two grazing seasons.
An Approach To Evaluate Soils Influence On Floristic Composition Of Natural Grasslands, F. L. F. De Quadros, R. M. R. De Carvalho, R. Farenzena, L. Marin, P. L. Nascimento
An Approach To Evaluate Soils Influence On Floristic Composition Of Natural Grasslands, F. L. F. De Quadros, R. M. R. De Carvalho, R. Farenzena, L. Marin, P. L. Nascimento
IGC Proceedings (1997-2023)
This trial aims to evaluate floristic composition of most abundant species in three soil typical of Pampa biome on Brazil. The survey was held at Maronna Fundation located on southern Alegrete municipality, on Rio Grande do Sul, Brazil’s state. Regional climate belongs to Koeppen’s Cfa class. Soil types were shallow basalt (Psamments e Orthents), deep basalt (Vertisols) and sandy soil (Acrisols or Ultisols). Floristic composition were evaluated by visual ranking of aerial biomass of the major species (transformed to kg of dry matter per hectare), calibrated by cuts at ground level, according to field procedures of BOTANAL method. Grasses were …
Determining Pasture Biodiversity With Nirs, K. J. Moore, D. J. Barker
Determining Pasture Biodiversity With Nirs, K. J. Moore, D. J. Barker
IGC Proceedings (1997-2023)
Research was conducted to assess the potential of using near infrared reflectance spectroscopy (NIRS) to determine botanical composition and measures of species diversity in pasture samples. Samples were collected from six hill country (Ballantrae) and two lowland (Aorangi) pastures in New Zealand. Samples were collected in summer (March) and Autumn (May) and subsamples were dissected to determine botanical composition and species diversity. Measures of diversity included species richness, Shannon’s index, and Simpson’s index. Reflectance data were collected from a second subsample that had been dried and finely ground. Calibrations were developed using modified partial least squares. Acceptable calibration equations were …
Study Of The Diversity Of Soil Animals Community In The Songnen Plain Grassland Of China, Xiuqin Yin, Tingcheng Zhu
Study Of The Diversity Of Soil Animals Community In The Songnen Plain Grassland Of China, Xiuqin Yin, Tingcheng Zhu
IGC Proceedings (1997-2023)
This paper dealt with the diversity in eight habitat soil animals communities in Songnen plain grassland. The results showed the better habitat condition the higher diversity index of soil animals, and vice-versa. The diversity of soil animals communities correlated positively with soil organic matter, total nitrogen, and negatively with soil pH; there was a poor correlation with soil water content and total soil phosphorus. The diversity of soil animals communities decreased with increasing depth of soil layer and has surface-collection.
An Assessment Of Grass Regeneration Nurseries At The Western Regional Plant Introduction Station, 1994-1997, V. L. Bradley, R. C. Johnson
An Assessment Of Grass Regeneration Nurseries At The Western Regional Plant Introduction Station, 1994-1997, V. L. Bradley, R. C. Johnson
IGC Proceedings (1997-2023)
The Western Regional Plant Introduction Station (WRPIS), Pullman, WA, USA, maintains over 17,000 accessions of forage and turf grasses that are mostly wind cross-pollinated and highly heterogenic. Regeneration procedures have been refined over the past nine years to include improved isolation distance and increased plant populations for regeneration. The grass regeneration nurseries planted from 1994 through 1997 were evaluated using data recorded in the Germplasm Resources Information Network (GRIN) and it was found that approximately 78% of the regenerations were successful. Reasons for failures were contributed to inadequate plant number, presence of disease, seed shattering, and unsuitable growing environment. Several …
The New Tendencies Of Environmental Impact Assessment Of Livestock Production: A Road Testing Of Leap/Fao Biodiversity Assessment Guidelines In Pastoral Systems In Uruguay, F. De Santiago, G. Pompozzi, M. Simó, Oscar Blumetto
The New Tendencies Of Environmental Impact Assessment Of Livestock Production: A Road Testing Of Leap/Fao Biodiversity Assessment Guidelines In Pastoral Systems In Uruguay, F. De Santiago, G. Pompozzi, M. Simó, Oscar Blumetto
IGC Proceedings (1997-2023)
After the publication of the “long shadow of cattle” report, ruminant production systems have received great pressure for their contributions in greenhouse gases (GHG). However, the environmental effects of human activities are much broader than GHG production and in some cases, there are positive contributions. In order to broaden the environmental perspective and with the encouragement of governments, the private sector and NGOs, LEAP-FAO has developed environmental assessment guidelines for the world's livestock production systems. This paper presents a road-testing of the Biodiversity Assessment Guideline at farm scale for six case studies in pastoral livestock systems in Uruguay. The producers …
Effects Of Agricultural Measures On Insect Diversity Of Alfalfa, Changzhong Liu
Effects Of Agricultural Measures On Insect Diversity Of Alfalfa, Changzhong Liu
IGC Proceedings (1997-2023)
No abstract provided.
Diversity Of Desert Rodent Communities Under Different Disturbances And Scales In Alashan Desert, Inner Mongolia, Heping Fu, Xiaodong Wu, Fushun Zhang
Diversity Of Desert Rodent Communities Under Different Disturbances And Scales In Alashan Desert, Inner Mongolia, Heping Fu, Xiaodong Wu, Fushun Zhang
IGC Proceedings (1997-2023)
No abstract provided.
Stolon Characteristic Of Hemarthria Compressa In The Southwest Of China, Jinping Liu, Xinquan Zhang
Stolon Characteristic Of Hemarthria Compressa In The Southwest Of China, Jinping Liu, Xinquan Zhang
IGC Proceedings (1997-2023)
No abstract provided.
What Caused The Degradation In 20 Years Of Elm (Ulmus Pumila L.) Woodland In China, Li Liu, Tingcheng Zhu
What Caused The Degradation In 20 Years Of Elm (Ulmus Pumila L.) Woodland In China, Li Liu, Tingcheng Zhu
IGC Proceedings (1997-2023)
No abstract provided.
In‐Herd Diversity Of Lifetime Performances: A Key For The Sustainability Of Livestock Farming System Based On Grassland, Laurence Puillet, D. Sauvant, M. Tichit
In‐Herd Diversity Of Lifetime Performances: A Key For The Sustainability Of Livestock Farming System Based On Grassland, Laurence Puillet, D. Sauvant, M. Tichit
IGC Proceedings (1997-2023)
No abstract provided.
Warming‐Induced Decline In Ecosystem Services Is Mitigated By Plant Traits On The Tibetan Plateau, Julia A. Klein, J. Harte, X. Q. Zhao
Warming‐Induced Decline In Ecosystem Services Is Mitigated By Plant Traits On The Tibetan Plateau, Julia A. Klein, J. Harte, X. Q. Zhao
IGC Proceedings (1997-2023)
No abstract provided.