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Articles 3061 - 3090 of 17792
Full-Text Articles in Entire DC Network
Developing Long-Term Weather Records For Use With Rangeland Management Modelsc, Clayton L. Hanson, J Ross Wight
Developing Long-Term Weather Records For Use With Rangeland Management Modelsc, Clayton L. Hanson, J Ross Wight
IGC Proceedings (1977-2023)
The use of natural resource models for research and management of rangeland ecosystems is limited by the unavailability of long-term weather records. This paper identifies sources of weather information for the United States; suggests methods for estimating missing records; and illustrates the use of double-mass curve procedures for evaluating the quality of data sets. Where weather data are limited in ducat ion or unavailable, stochastic weather generation is an option to simulate daily weather records.
Making Models Easy To Use, J Ross Wight, Clayton L. Hanson
Making Models Easy To Use, J Ross Wight, Clayton L. Hanson
IGC Proceedings (1977-2023)
A major limitation to the application of natural resource models to resource management problems is the unavailability of input information and complexity of model operation and output interpretation. These problems can be moderated by using synthetic weather data, algorithms and expert systems to calculate model parameters and input variables and computer programs to simplify development of input data files and interpretation of output results. This paper summarises some of the procedures and techniques that can be used to make models easier to use and more useful as management tools.
Simulation Models As Decision Aids For Management Of Rangeland Ecosystems, J Ross Wight, Clayton L. Hanson
Simulation Models As Decision Aids For Management Of Rangeland Ecosystems, J Ross Wight, Clayton L. Hanson
IGC Proceedings (1977-2023)
Rangeland simulation models have been used primarily as research tools to synthesise and organise information and to conceptualise and describe the interacting components of the ecosystem. Their application as decision aids for range management has not been developed. This paper discusses ways simulation models, such as SPUR· (Simulation of Production and Utilisation of Rangelands), can be used to forecast herbage p1oduction and the occurrence of biological windows, enhance monitoring, and predict the impacts of management and climate change on the soil, water, and plant resources including species composition.
Models Of Pasture Production To Aid On-Farm Decision Making In New Zealand, J A. Baars, M D. Rollo
Models Of Pasture Production To Aid On-Farm Decision Making In New Zealand, J A. Baars, M D. Rollo
IGC Proceedings (1977-2023)
Two microcomputer-based predictive pasture models, for use in decision making by agricultural consultants and industry, are described. The first model (GRASS) was developed to understand the interactions between environment and management. The second model supplies pasture growth rates for current or predicted weather conditions by adjustment of stored actual average fortnightly pasture growth rates for a wide range of measurement sites. Ways are described in which the models are being used in transfer of technology.
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 …
Microeukaryote Metabolism Across The Western North Atlantic Ocean Revealed Through Autonomous Underwater Profiling, Natalie R. Cohen, Arianna I. Krinos, Riss M. Kell, Rebecca J. Chmiel, Dawn M. Moran, Matthew R. Mcilvin, Paloma Z. Lopez, Brianna A. Alanis, Eric W. Chan, John A. Breier
Microeukaryote Metabolism Across The Western North Atlantic Ocean Revealed Through Autonomous Underwater Profiling, Natalie R. Cohen, Arianna I. Krinos, Riss M. Kell, Rebecca J. Chmiel, Dawn M. Moran, Matthew R. Mcilvin, Paloma Z. Lopez, Brianna A. Alanis, Eric W. Chan, John A. Breier
School of Earth, Environmental, & Marine Sciences Faculty Publications
Microeukaryotes are key contributors to marine carbon cycling. Their physiology, ecology, and interactions with the chemical environment are poorly understood in offshore ecosystems, and especially in the deep ocean. Using the Autonomous Underwater Vehicle Clio, microbial communities along a 1050 km transect in the western North Atlantic Ocean were surveyed at 10–200 m vertical depth increments to capture metabolic signatures spanning oligotrophic, continental margin, and productive coastal ecosystems. Microeukaryotes were examined using a paired metatranscriptomic and metaproteomic approach. Here we show a diverse surface assemblage consisting of stramenopiles, dinoflagellates and ciliates represented in both the transcript and protein fractions, …
Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud
Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud
Theses and Dissertations
Dust derived from southern South America provides critical nutrients for autotropic marine biota in the South Atlantic Ocean, such that fluxes of wind-blown sediment may ultimately affect the concentration of atmospheric CO2. Expansive sand, silt, and loess deposits are exposed in Central Argentina, recording millions of years of eolian processes; however, the provenance and transport pathways of this dust remains unclear. Coastal loess deposits ranging in age from Pliocene to upper Pleistocene are present along the Atlantic margin of Argentina and provide information on sediment transport pathways for the last 4 million years. Nine samples of loess were collected and …
Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane
Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane
International Journal of Speleology
Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …
Assessing Multi-Annual Phytoplankton Community Compositions And Biomass Across Tidal Creek And Open Water Estuarine Habitats In South Carolina, Shannon Elizabeth Powers
Assessing Multi-Annual Phytoplankton Community Compositions And Biomass Across Tidal Creek And Open Water Estuarine Habitats In South Carolina, Shannon Elizabeth Powers
Theses and Dissertations
The urbanization of coastal environments in recent decades has caused an accelerating increase in nutrient-rich runoff from the landscape. The presence of these excess nutrients in the aquatic environment can result in degradation of water quality and harmful algal blooms. In South Carolina (SC), coastal development continues to threaten the resiliency of salt marsh estuaries, especially in combination with other stressors like climate change and sea level rise. Estuaries are important nurseries and habitats for fisheries and ecotourism. The South Carolina Estuarine and Coastal Assessment Program (SCECAP) is an ongoing monitoring program that assesses the habitat condition along the coast …
Hypogenic Caves Of Syracuse Area, Sicily (Italy): Geomorphological Evidence Of Co2 Degassing, Fresh-Salt Water Mixing, And Late Condensation Corrosion, Philippe Audra, Jean-Yves Bigot, Didier Cailhol, Pierre Camps, Ilenia M. D'Angeli, Hai Cheng, R. Lawrence Edwards, Fernando Gàzquez-Sanchez, Gabriella Koltai, Giuliana Madonia, Jean-Claude Nobécourt, Marjan Temovski, Marco Vattano, Jo De Waele
Hypogenic Caves Of Syracuse Area, Sicily (Italy): Geomorphological Evidence Of Co2 Degassing, Fresh-Salt Water Mixing, And Late Condensation Corrosion, Philippe Audra, Jean-Yves Bigot, Didier Cailhol, Pierre Camps, Ilenia M. D'Angeli, Hai Cheng, R. Lawrence Edwards, Fernando Gàzquez-Sanchez, Gabriella Koltai, Giuliana Madonia, Jean-Claude Nobécourt, Marjan Temovski, Marco Vattano, Jo De Waele
International Journal of Speleology
Many caves in Sicily have been shown to have a sulfuric acid or other hypogenic origin. We studied three caves (Palombara, Scrivilleri, Monello) near Syracuse (eastern Sicily), in an area that was strongly uplifted and faulted, creating multiple Pleistocene marine terraces. Mineralogy, stable isotopes and dating methods (paleomagnetism, U/Th) were used to characterize cave sediments, some of which were related to the initial hypogenic phase (Fe and Mn oxides, calcite spar), others were introduced by surface runoff later. Many other sediments are the result of in situ weathering, such as lime sands produced by condensation-corrosion processes on the calcarenite walls. …
Microbial Phosphate Solubilization Mechanisms In P Solubilizing In Andisol, Agustina Erlinda Marpaung, Tengku Sabrina, Abdul Rauf, Dwi Ningsih Susilowati, Luthfi Aziz Mahmud Siregar
Microbial Phosphate Solubilization Mechanisms In P Solubilizing In Andisol, Agustina Erlinda Marpaung, Tengku Sabrina, Abdul Rauf, Dwi Ningsih Susilowati, Luthfi Aziz Mahmud Siregar
Jurnal Kultivasi
Phosphate (P) nutrient plays a significant role in plant growth and yield. P is an essential element that plays an important role in photosynthesis and root development. Phosphate nutrient availability is deficient in some soil types due to retention, such as in Andisol soil types. High phosphate retention in Andisol soil types causes P nutrients to be unavailable to plants and can reduce crop yields. The availability of P in Andisol soils can be done, among others, by applying phosphate solubilizing microbes. Phosphate solubilizing microorganisms are soil microorganisms consisting of bacteria and fungi that can mineralize organic P, dissolve inorganic …
Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois
Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois
Electronic Theses and Dissertations
Chinese tallow (Triadica sebifera (L.) Small) is an invasive tree known to have negative impacts on bottomland hardwood forests. Chinese tallow is proficient in reproducing and surviving in bottomland hardwood forests because it is more flood and shade tolerant than most native trees. The long-term effectiveness of Chinese tallow control is an important topic to research as only a few long-term studies of Chinese tallow control have been conducted. A 10-year re-measurement of 22 paired plots installed in 2012 on the Pineywoods Mitigation Bank near Diboll, Texas following herbicide treatments examined Chinese tallow and native tree stand structure. Each …
Structural Characterization Of The Puma Diapir, Gulf Of Mexico Basin, Rodrigo Velasquez
Structural Characterization Of The Puma Diapir, Gulf Of Mexico Basin, Rodrigo Velasquez
Electronic Theses and Dissertations
The Gulf of Mexico (GOM) Basin has been a significant target for oil and gas since the 1990s and continues today as a leading exploration target. This super basin is home to an estimated 200 BBOE (Billon barrels of oil equivalent), with current production totaling 60 BBOE for both USA and Mexico. Even though the overall depositional evolution of the GOM has allowed for the key elements for petroleum accumulations to be met, a complex structural framework is present. This framework results from the asymmetric spreading of the North American Plate from the Yucatan block crating the GOM basin we …
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 …