Physical Sciences and Mathematics Commons^™

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

IGC Proceedings (1997-2023)

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.

Forage Grasses And Legumes With Broad Adaptation For Southeast Asia, Ibrahim, E Lanting, C Khemsawat, C C. Wong, Liu Guodao, V Phimphachanhvongsod, L H. Binh, P M. Horne

IGC Proceedings (1997-2023)

A wide range of forages is currently being evaluated by farmers and researchers in seven countries in Southeast Asia. Broadly-adapted species have been identified for fodder banks, grazed systems, tree cropping, erosion control and improved fallows. The most promising accessions to date are Stylosanthes guianensis CIAT 184, Brachiaria decumbens cv Basilisk, Brachiaria humidicola cv Tully and CIAT 6133, CIAT 6780, Centrosema pubescens CIAT 15160 and Andropogon gayanus cv Kent and CIAT 621. Other forages that show promise are Paspalum atratum, Arachis pintoi, and Macroptilium gracile cv. Maldonado. Local seed supply and distribution systems are needed to ensure that …

Exploring Profitable, Sustainable Livestock Businesses In An Increasingly Variable Climate, B. R. Cullen, M. T. Harrison, D. Mayberry, D. Cobon, N. Reichelt, A. Sinnet, Km Christie, F. Bilotto, D-A An-Vo, C. Stokes, L. Perry, T. Davison

IGC Proceedings (1997-2023)

Livestock production systems will need to change in many regions of the world to meet the dual challenges of adaptation to a changing climate and reducing net greenhouse gas (GHG) emissions. The ‘Nexus project’ is exploring these options using seven case studies in eastern Australia spanning a range of production systems from semi-arid beef production in northern Australia to mixed beef and sheep production in cool temperate climates of southern Australia. Regional reference groups, made up of 4-6 local farmers and advisers, identified a series of farm systems changes that could be made to meet these challenges. Options were categorised …

Perennial Ryegrass ‘Virazón’, A New Cultivar For Warm Temperate Areas In Uruguay And South America., Felix Gutiérrez, Javier Do Canto, R. Reyno, C. Rossi, A. Stewart, M. Carrere, F. Nolla

IGC Proceedings (1997-2023)

‘Virazón’ perennial ryegrass (Lolium perenne L.), a grazing-type tetraploid cultivar, was developed by the National Institute of Agricultural Research (INIA) in Uruguay as a part of the Joint Venture with PGG Wrightson Seeds and Grasslands Innovation Limited and commercially available since 2021. ‘Virazón’ was developed after 6 cycles of selection from crosses with cultivar Horizon from New Zealand based on climate adaptation, dry matter production, vigor, rust resistance, seed yield, and persistence under Uruguayan conditions. The aim was to obtain a perennial ryegrass with 3 years of consistent production. ‘Virazón’ was evaluated in forage yield trials in comparison with …

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 …

Herders And Wetland Degradation In Northern Cameroon, E. Tedonkeng Pamo, F. Tendonkeng, J. R. Kana

IGC Proceedings (1997-2023)

Livestock rearing in Northern Cameroon is carried out under two majors systems: the nomadic and the transhumance production systems (Pamo & Pamo, 1991). Nomadism is the practice of wandering from place to place, while transhumance involves seasonal displacement of flocks from one area to another by herders. These production systems involved large grazing areas, which may encompass different ecosystems. The Yaére, the only wetland of the northern Cameroon, is the major dry season grazing lands for livestock and wildlife. The main characteristic of this wetland is that the whole area is excluded from grazing during the growing season as a …

Adaptation, Compatibility And Acceptability Of Grass-Legume Pastures In The Andean Region Of Colombia, E. Cárdenas, E. Castro

IGC Proceedings (1997-2023)

In Colombia, the specialised dairy production system is located in the high altitude Andean region. Its main feed resources are pure stands of Pennisetum clandestinum or/and Lolium spp. Nevertheless, the present market conditions require highly competitive and quality forages year round. These forages should be produced with low inputs (irrigation, fertilisers and agrochemicals) and be resistant to pests and diseases. The objective of this research was to evaluate the adaptation, compatibility and acceptability of introduced forage species for sustainable pasture management.

Herders And Wetland Degradation In Northern Cameroon, E. Tedonkeng Pamo, F. Tendonkeng, J. R. Kana

IGC Proceedings (1997-2023)

Livestock rearing in Northern Cameroon is carried out under two majors systems: the nomadic and the transhumance production systems (Pamo & Pamo, 1991). Nomadism is the practice of wandering from place to place, while transhumance involves seasonal displacement of flocks from one area to another by herders. These production systems involved large grazing areas, which may encompass different ecosystems. The Yaére, the only wetland of the northern Cameroon, is the major dry season grazing lands for livestock and wildlife. The main characteristic of this wetland is that the whole area is excluded from grazing during the growing season as a …

Genetic Resources For Tropical Areas: Achievements And Perspectives, Cacilda B. Do Valle

IGC Proceedings (1997-2023)

This paper analyses the present status of tropical forage resources and their utilization in the development of novel cultivars based on the accumulated information from past decades of collecting, evaluation and whatever little breeding has been pursued. The situation of world collections of tropical forages is presented and discussed in the light of limited investment and dwindling resources. A cause for concern is the lesser priority assigned to conservation and manipulation of official tropical germplasm banks, such as CSIRO’S and CIAT’s. In order to assure the availability of tropical genetic resources for the future it is imperative that international efforts …

Genotype-Environment Interaction For Forage Yield Of Vetch (Vicia Sativa L.) In Mediterranean Environments, G. Pacucci, C. Troccoli

IGC Proceedings (1997-2023)

Genotype x environment (GE) interactions limit the effectiveness of selection when selection is based only on mean yields. The objective of this study was to evaluate the amount of GE interaction for vetch forage yield in some environments of Southern Italy, and to analyze some stability parameters that can be useful in the selection of genotypes adapted to Mediterranean environmental conditions. Eleven vetch genotypes were grown in a total of 16 environments in Southern Italy. The combined analysis of variance for forage yield showed that the environment, genotype and GE interaction terms were significant at 0.01 level, suggesting a broad …

Perceptions Of Gauteng Beef Farmers On Significance Of Practising Climate Smart Agriculture, S. T. Jiyana, K-J. Leeuw, Abubeker Hassen, Ignatius V. Nsahlai

IGC Proceedings (1997-2023)

Farmers are crucial role-players in agriculture, especially in beef farming. Daily farm activities affect climate change, either negatively or positively. Therefore, farmers’ ability to relate climate change with farm activities is highly imperative. A study was conducted to investigate perceptions of Gauteng beef farmers on significance of practising climate smart agriculture (CSA). Semi-structured key informant interviews were conducted with 57 beef cattle farmers from three areas (Bronkhorstspruit, Rust de Winter and Cullinan) of Tshwane region (Gauteng province). A fully detailed ethical statement was used to explain the study and request farmers’ participation. Data analysis was done using a Statistical Package …

Adaptation Of Forage Species To Drought, D. J. Barker, J. R. Caradus

IGC Proceedings (1997-2023)

Variability in rainfall is the single greatest cause of variation in forage production for a given site. Current climate scenarios predict future annual rainfall to decrease at some geographic regions. The intensity of future rainfall is also predicted to increase at other regions, with the expectation of greater variability in soil moisture. The adaptation of forage species to drought is an issue that is likely to remain with us into the future.

Precise definitions are critical to water relations work, and imprecise use of terms has complicated comparisons of some studies on plant response to drought. Drought is a purely …

Telomere Roles In Fungal Genome Evolution And Adaptation, Mostafa Rahnama, Baohua Wang, Jane Dostart, Olga Novikova, Daniel Yackzan, Andrew T. Yackzan, Haley Bruss, Maray Baker, Haven Jacob, Xiaofei Zhang, April Lamb, Alex Stewart, Melanie Heist, Joey Hoover, Patrick Calie, Li Chen, Jinze Liu, Mark L. Farman

Plant Pathology Faculty Publications

Telomeres form the ends of linear chromosomes and usually comprise protein complexes that bind to simple repeated sequence motifs that are added to the 3′ ends of DNA by the telomerase reverse transcriptase (TERT). One of the primary functions attributed to telomeres is to solve the “end-replication problem” which, if left unaddressed, would cause gradual, inexorable attrition of sequences from the chromosome ends and, eventually, loss of viability. Telomere-binding proteins also protect the chromosome from 5′ to 3′ exonuclease action, and disguise the chromosome ends from the double-strand break repair machinery whose illegitimate action potentially generates catastrophic chromosome aberrations. Telomeres …

Domestication Of Mediterranean Annual Pasture Legumes For Australian Farming Systems, P. G. H. Nichols, Angelo Loi, B. J. Nutt, R. Snowball, Clinton K. Revell

IGC Proceedings (1997-2023)

No abstract provided.

Nguni--A New Old Cattle Breed For Rangelands In Communal Areas Of South Africa, Wolfgang Bayer, Brigid Letty, Rauri Alcock

IGC Proceedings (1997-2023)

No abstract provided.

Trigonella Arcuate Responds To Seriphidium Transillense Desert Degraded Grassland, H. L. Liu, Kun Wang, J. Z. Zhu, J. Wang

IGC Proceedings (1997-2023)

No abstract provided.

Adaptation Benefit Two Grass Coexisting In Meadow Steppe Of Northeast China, Lei Ba, Wei Xu, Deli Wang

IGC Proceedings (1997-2023)

No abstract provided.

Adaptation To Changing Institutional, Market And Bio-Physical Environments: The Case Of China’S Grasslands, Colin G. Brown, Scott A. Waldron, John W. Longworth

IGC Proceedings (1997-2023)

In the modern world, small pastoral herder households living on grasslands in countries such as China face major challenges in adapting to changes in their institutional, market and bio-physical environments. In China, these changes have been profound over the last 30 years. Herders, their communities and others dependent on the grasslands have responded to these developments but not always as might be expected. In this paper, the sources of the macro-forces in China that have created the pressure for change at the grass roots are outlined and the micro-adjustments made by herders and others in response to these pressures are …

Impacts Of Climate Change On Livestock Systems: What We Know And What We Don’T Know, Mark Howden, S. Schroeter, S. Crimp, C. Stokes

IGC Proceedings (1997-2023)

Climate changes and the associated increases in atmospheric carbon dioxide concentration are just two of many possible future drivers of change in grassland systems and whilst there are significant uncertainties around these, they are probably more effectively characterised than many other drivers. The challenge for grasslands systems research is not so much trying to precisely predict future climate in the face of unresolvable uncertainty but rather to work with decision-makers to enhance their decisions for a range of possible climates, build their capacity to make sound risk-based and informed decisions and increase the array of options available for adaptation. There …

Assessing Climate Change Impacts On Managed Grassland Production Using A Bio-Economic Modelling Approach, Robert Finger, Pierluigi Calanca, Simon Briner

IGC Proceedings (1997-2023)

We develop a bio-economic model that combines the process based grassland simulation model PROGRASS with an economic decision model, which accounts for income risks and yield quality, to derive optimal nitrogen application rates in a grass-clover system in Switzerland. The model is applied to current as well as to future climate conditions. Though nitrogen increases yields, it also leads to a higher variance and more negative skewness of yields, i.e. is risk increasing. Accounting for farmers’ risk aversion thus reduces optimal nitrogen use. We find climate change, ceteris paribus, to lead to higher grassland yields but also to increase the …

Commercialisation And Impacts Of Pasture Legumes In Southern Australia–Lessons Learnt, Clinton K. Revell, Michael A. Ewing, Daniel Real, Phillip G. H. Nichols, Graeme A. Sandral

IGC Proceedings (1997-2023)

Forage legumes are a key feature of temperate grasslands in southern Australia, valued for their ability to increase animal production, improve soil fertility and fix atmospheric nitrogen. Of the 36 temperate annual legume and 11 temperate perennial legume species with registered cultivars introduced or domesticated in Australia over the last 100 years, a third have made a major contribution to agriculture, a third have modest use and a third have failed to make any commercial impact. Highly successful species include subterranean clover, barrel medic, white clover, lucerne, French serradella and balansa clover. Species were assessed on the scale of their …

Managing Grassland Systems In A Changing Climate: The Search For Practical Solutions, Jean-François Soussana, Luis Gustavo Barioni, Tamara Ben Ari, Rich Conant, Pierre Gerber, Petr Havlik, Alexandre Ickowicz, Mark Howden

IGC Proceedings (1997-2023)

By the end of the XXI^st century, a global temperature rise between 1.5 and 4°C compared to 1980-1999 and CO₂ concentrations in the range 550-900 ppm are expected, together with an increased frequency of extreme climatic events (heat waves, droughts, and heavy rain) that is likely to negatively affect grassland production and livestock systems in a number of world regions. Grassland management has a large potential to mitigate livestock greenhouse gas emissions at a low (or even negative) cost, by combining a moderate intensification, the restoration of degraded pastures and the development of silvo-pastoral systems. Climate change vulnerability …

Analysis Of Environment-Marker Associations In American Chestnut, Markus Müller, Charles Dana Nelson, Oliver Gailing

Forest Health Research and Education Center Faculty Publications

American chestnut (Castanea dentata Borkh.) was a dominant tree species in its native range in eastern North America until the accidentally introduced fungus Cryphonectria parasitica (Murr.) Barr, that causes chestnut blight, led to a collapse of the species. Different approaches (e.g., genetic engineering or conventional breeding) are being used to fight against chestnut blight and to reintroduce the species with resistant planting stock. Because of large climatic differences within the distribution area of American chestnut, successful reintroduction of the species requires knowledge and consideration of local adaptation to the prevailing environmental conditions. Previous studies revealed clear patterns of genetic …

Rainwater Harvesting And Its Impact On Farming Systems, J. S. Samra

IGC Proceedings (1997-2023)

Landless, small holders and other poors supplement their livelihood and adapt to climate change by grazing, stall feeding with crop residues and fodder cultivated under rainfed and irrigated conditions. Improving productivity by conserving rainfall, ground water recharging, harvesting and recycling of rainwater especially in degraded open access or shared land with community participation was quite successful over a wide range of precipitation and ecological situations. Various types of trenches, bunding, vegetative barriers, gully plugs, ponds, check dams, land slides and mine spoils stabilization etc. retained more soil moisture, seeds, vegetative propagules etc. in situ and prevented soil erosion. It regenerated …