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Effect Of Dormancy-Releasing Treatments On Germination Of Bahiagrass Seed, J. Jeffrey Mullahey, D S. Fisher 2024 Southwest Florida Research Center

Effect Of Dormancy-Releasing Treatments On Germination Of Bahiagrass Seed, J. Jeffrey Mullahey, D S. Fisher

IGC Proceedings (1977-2023)

Low seed germination and dormant seed in bahiagrass (Paspalum nonatutum Flugge.) necessitate high seeding rates for successful pasture establishment. A study of dormancy-releasing treatments and age of seed on germination of bahiagrass was conducted in an incubator at the Southwest Florida Research and Education Center near Immokalee, Florida. Five seed treatments (Crop-Start (Solid Matrix Seed Priming, Kamterter Products Inc., Lincoln, NB), potassium nitrate (KNO3), heat/humidity, palea removed, and a check), 2 cullivars (Pensacola, Tifton 9) of bahiagrass and 2 ages (10 and 16 months) of seed were used. A significant (P<0.05) age ·x treatment interaction occurred for all response variables. Based on total germination at 28 days, % dormant seed and rate of germination, Crop-Start and heat/humidity were consistently the best treatments. Additional research on germination with dormancy-releasing treatments is needed to study the Interaction of seed age and bahiagrass cultivar.


Weed Seed Contamination: Use Of A Seed Testing Database To Identify Processing Limitations, J S. Rowarth, M P. Rolston, A A. Johnson 2024 AgResearch, NZ

Weed Seed Contamination: Use Of A Seed Testing Database To Identify Processing Limitations, J S. Rowarth, M P. Rolston, A A. Johnson

IGC Proceedings (1977-2023)

A computerised database maintained by the Official Seed Testing Station of New Zealand provided the opporlunity to survey weed seed contamination in clover and grass seed-lots. Broad-leaf weeds such as Slierardia arvensis, Stellaria ,nedia and Chenopodium album were the major contaminants in Trifolium repens seed-lots. In grass seed-lots the main contaminants were seeds of other grasses such as Bromus hordaeceus, Vulpia spp. and Holcus lanatus. Weed seeds were found to be a major reason for downgrading or rejection from certification of clover and grass seed-lots in New Zealand; this reflects strict quality control measures.


An Investigation In To The Effect Of Some Factors On The Germination Of Erodium Seeds, Myrna Johnston, Alfredo Olivares, Gladys Fernandez 2024 Laboratorio Fisiologia Vegetal

An Investigation In To The Effect Of Some Factors On The Germination Of Erodium Seeds, Myrna Johnston, Alfredo Olivares, Gladys Fernandez

IGC Proceedings (1977-2023)

Erodiurn seeds present variable dormancy in and even within each species. Thus, it is important to know the factors that determine this variation as related to the persistence of its species. E. rnoschatmn and E. rnalacoides seeds were collected at the end of the annual cycle at La Rinconada de Maipli (33°28'S and 7S050'W). Effects of seed sour.ce (collecting in 1986, 1988 and 1990), age (keeping seeds under laboratory conditions) and maternal factors (cutting plants at early flowering) were analysed. Seeds were tested for germination capacity and germination rate at a constant temperature of 15°C on Petri dishes provided with …


Long-Term Seed Dormancy In Poa Pratensis L. Northern Norway, Trygve S. Aamlid, Dagfinn Arntzen 2024 Landvik Research Station

Long-Term Seed Dormancy In Poa Pratensis L. Northern Norway, Trygve S. Aamlid, Dagfinn Arntzen

IGC Proceedings (1977-2023)

Inadequate gennination has often been obseived when planting Poa pratensis L. cv. Lavang (69°N) in northern Norwegian grasslands. This investigation was intended to elucidate whether this was due lo long­term seed dormancy, Seed-lots grown in different years in northern and southern Norway and stored at O-to•c, were germinated in Jakobsen­type germinators al various combinations of temperature and light. Significant dormancy was expressed at 21 °C even after 10 years of storage. Al this constant temperature, germination was promoted by 8 h fluorescent light compared with darkness and continuous light. Al 21/ I 2°C alternating temperature, seed genninated well irrespective of …


Seed Vigour In Lucerne And White Clover, Y R. Wang, J G. Hampton 2024 Gansu Grassland Ecological Research Institute

Seed Vigour In Lucerne And White Clover, Y R. Wang, J G. Hampton

IGC Proceedings (1977-2023)

Accelerated ageing (AA) was used to assess the seed vigour of 5 lucerne (Medicago sativa L, cv. Wairau) and 8 white clover (Trifolium repens L. cv. Grasslands Huia) seed-lots. Germination prior to AA ranged from 86-94% and 87-94% for the lucerne and white clover seed-lots respectively. All seed-lots hl\d been harvested in 1988 and were certified either as basic or first generation. Germination after 72 h at 40:t0.5°C (AA test) ranged frcim 31-76% for the lucerne seed­lots and 15-56% for che white clover seed-lots, indicating significant differences in seed.vigour among lots of both species. Time of ageing influenced …


Growing Methods For The Morphological Assessment Of White Clover Cultivars Purity, J G. Hampton, E J. Musukwa 2024 Massey University

Growing Methods For The Morphological Assessment Of White Clover Cultivars Purity, J G. Hampton, E J. Musukwa

IGC Proceedings (1977-2023)

Three growing methods (field sward, field spaced plants, glasshouse plants) were compared for the morphological assessment of white clover (Trifolium repens L.) cultivar purity. Three cerlified (breeders, basic and first generation) seed-lots of cv. Grasslands Kopu and one first generation Kopu seed lot which had been mixed with seed of another cultivnr (10:1) were used to generate data. After analysis of variance (ANOVA), significant (P<0.05) reductions from the breeders seed lot siandnrd for leaf size, stolon number and leaf length/width ratio were recorded for the mixed seed· 101 in nil three growing methods, and for petiole length with the sward method only. With the glasshouse and spaced-plant melhods, slolon numbers of the basic and first generation seed-lots were reduced (P<0.05), while leaf size was lower (P<0.05) for the first generation seed-lot in lhe glasshouse. However, under OECD certification requirements, leaf size of the mixed seed lot was the only characler for which "off types" were detecled. Data coefficients of variation were no greater for the glasshouse method than the required OECD plot-test method.


Importance Of Tropical Pasture Seed Quality And Factors Affecting It In Smallholder Farming System, H F. Chin, C C. Wong 2024 Agronomy Department Universiti Pertanian Malaysia

Importance Of Tropical Pasture Seed Quality And Factors Affecting It In Smallholder Farming System, H F. Chin, C C. Wong

IGC Proceedings (1977-2023)

Most tropical pastures are associated with and confined to smaJlholder animal production in developing countries of the tropics, with the exception of Australia. At present, tropical pasture seeds are very variable and poor in quality, as tropical herbage seed production is relatively new compared with that for temperate systems. Many tropical species are relatively wild and have yet to be domesticated and selected for pasture use, let alone for seed production characteristics. The unfavourable production and storage environment of the wet tropics, coupled with a lack of appropriate technology, also contributes towards poor quality in tropical pasture seeds. In this …


The Benefits Of Seed Quality In Intensive Temperate Forage Systems, Jeffrey J. Steiner 2024 USDA, Agricultural Research Service

The Benefits Of Seed Quality In Intensive Temperate Forage Systems, Jeffrey J. Steiner

IGC Proceedings (1977-2023)

Seed quality has traditionally been considered to consist of two components: physiologic and genetic quality. The benefits of using high quality seeds have been widely documented and are generally not questioned. These henefits came about as a result of a first­generation of seed quality aware11ess which began more than a century ago. In intensive temperate forage production systems, the producer usually has a ready supply of high-quality seeds available for purchase. For the consumer, seed quality is not a major constraint to system productivity, However, many forage producers are not realising all of the potential benefits from using high quality …


New Realities For The Management Of Tussock Grasslands In New Zealand, I.G C. Kerr 2024 Lincoln University

New Realities For The Management Of Tussock Grasslands In New Zealand, I.G C. Kerr

IGC Proceedings (1977-2023)

Concerns about the potential demise of the tussock grasslands of the Soulh Island of New Zealand have been well recorded in the scientific and official literature. Little effective action has been taken to arrest the process of land degradation that has occurred during the 125 years of utilisation of !he tussock grasslands for pastoralism. A substantial decline in the pastoral productivity and conservation value of the "unimproved" tussock grasslands has been the result, Much of the cause has been the failure of the administrators and the occupiers of the high country to understand, and act on, the evidence. Occupiers and …


Integration Of Recreation With Pastoral Use And Conservation In The High Country Of South Island, New Zealand, P H. Murray, D M. Robertson, C R. Mason 2024 Landcorp Management Services

Integration Of Recreation With Pastoral Use And Conservation In The High Country Of South Island, New Zealand, P H. Murray, D M. Robertson, C R. Mason

IGC Proceedings (1977-2023)

Over 3 000 000 ha of the South Island high country is Crown (i.e. Govemmcnt)-owned land, held under pastoral lease or conservation estate. There is increasing pressure from recreationists for access to land under both tenures. Permits from Crown agents, with agreement from land occupiers, are required for commercial recreation. Access for non-commercial recreation on pastoral lease land is generally through direct negotiation with the lessee. Conflicts between high country users are occurring where recreation pressure is greatest. A case study in the Remarkables Range near the mountain resort of Queenstown, shows domination by the primary users (pastoral lessees and …


Tradition And Pastoral Sustainability- An Exercise In The Applied Human Ecology Of Mountain Rangelands, David Pitt 2024 Switzerland

Tradition And Pastoral Sustainability- An Exercise In The Applied Human Ecology Of Mountain Rangelands, David Pitt

IGC Proceedings (1977-2023)

The paper presents the case for regarding some traditional practices and customs as a ba��e for sustainable development in winter cold temperate rangeland pastoralism, The emphasis is on the social forms which maintain a system in which low intensity production, usufruct, kinship dynamics, co-operation, environmentally friendly practices and nomadism are maintained in the face of extreme outside pressures, A typology is elaborated including five situations: independence, coexistence, fluctuation, absorption and interaction. Case studies _are presented from the Middle East, Andes, North Africa, the Alps, the Himalaya and the former Soviet Union. Although these situations are basically historical, or at best …


Integration Of Pastoral And Non-Pastoral Uses On Temperate Rangelands With Cold Winters In Developed Countries, T J. Maxwell, W A. Laycock 2024 Macaulay Land Use Research Institute

Integration Of Pastoral And Non-Pastoral Uses On Temperate Rangelands With Cold Winters In Developed Countries, T J. Maxwell, W A. Laycock

IGC Proceedings (1977-2023)

The demands of the relatively wealthy and sophisticated societies of developed countries, with their substantial amounts of leisure time and discretionary income, are having an increasing impact on temperate rangelands in a variety of ways. Some parts of these societies are concerned to protect the landscapes, habitats, wildlife and solitude that can be found there, and wish to constrain any further development within these ecosystems; others also wish .to gain ready access to these resources for hunting, recreation and sport and believe that this requires the exclusion of domesticated livestock. Temperate rangelands are frequently used as water catchments and some …


Effects Of Date Of Harvest On Yield And Quality Of Meadow Fescue Seed, Uwe Simon 2024 TUM Lehrstuhl fur Grunland und Futterbau

Effects Of Date Of Harvest On Yield And Quality Of Meadow Fescue Seed, Uwe Simon

IGC Proceedings (1977-2023)

A seed-shattering-resistant cultivar and a normal cultivar of meadow rescue (Festuca pratensis Huds.) were harvested for seed 10 times in regular intervals during a period of 30 days, The effects of harvesting time on yield, water content, germination and weight of seeds, and on costs of seed processing were studied in the 2 types of cultivar. Yield losses due to premature harvest were greater than losses due to delayed harvest. Seed losses due to shattering were smaller in the shattering-resistant cultivar compared with the normal cultivar. The water content of the seeds decreased with advancing maturity, from =50% to .. …


After-Effects Of Grass Seed Production On Subsequent Field Crops, Uwe Simon 2024 TUM Lehrestuhl fur Grunland and Futterbau

After-Effects Of Grass Seed Production On Subsequent Field Crops, Uwe Simon

IGC Proceedings (1977-2023)

Forage grasses grown for the production of seed are usually components of a crop rotation. The after-effects of 3 grass species compared with 4 crop species on the yields of 5 field crops in the first and second year after grass seed harvest were investigated. Significant differences between the grass species, and between grasses and other field crops on subsequent crops, and between the subsequent crops in their reactions to the preceding crops were obvious in both years after grass seed harvest, Annual and perennial ryegrass excited the most positive effects on subsequent crop yields. Corn and sugarbeets responded particularly …


A New Power Airflow Harvester Improves Grass Seed Yield And Quality In Central Queensland, Australia, J H. Wildin, Dingfa Zhou, A Dobson 2024 Department of Primary Industries and Regional Development, Western Australia

A New Power Airflow Harvester Improves Grass Seed Yield And Quality In Central Queensland, Australia, J H. Wildin, Dingfa Zhou, A Dobson

IGC Proceedings (1977-2023)

Most perennial tropical grasses produce new seedheads over a period extending up to 4 weeks, Seeds mature and ripen up to 4 weeks after inflorescence emergence. The dilemma for seed producers using one­pass harvesting has been to time the harvesting operation to maxmise. recovery of mature seed, Harvested immature seeds and inert material adversely affect seed purity and germination tests. Light fluffy seeds such as buffel and bluegrasses are generally difficult to harvest with grain crop harvesters, and paddle beater harvesters have been used for simplicity and economy. Over the last 3 years, tractor-mounted brush harvesters using 4 rows of …


Evaluation And Development Of Brush Harvesting For Chaffy-Seed Grasses In Queensland, Australia, T A. Jensen, D S. Loch, B G. Robotham 2024 Queensland Department of Primary Industries

Evaluation And Development Of Brush Harvesting For Chaffy-Seed Grasses In Queensland, Australia, T A. Jensen, D S. Loch, B G. Robotham

IGC Proceedings (1977-2023)

Lack of an effective seed harvester has limited the commercial availability of many chaffy-seeded grasses in Australia. A brush harvester similar to the Woodward Plail-Vac. Seed Stripper was evaluated successfully across a range of chaffy-seeded grasses in southern Queensland. A second machine with increased harvesting and storage capacity plus a facility for primary cleaning of seed was designed and built for large-scale commercial use. A third harvester is currently being developed for opportunist harvesting of small discontinuous seed areas, particularly of chaffy-seeded native grasses in the, semi-arid mulga lands in south-western Queensland; it is designed for low-cost construction and maintenance …


The Woodward Flail-Vac Seed Stripper: Recent Progress In Harvesting Chaffy Seed, C L. Dewald, P L. Sims, L M. White 2024 Southern Plains Range Research Station

The Woodward Flail-Vac Seed Stripper: Recent Progress In Harvesting Chaffy Seed, C L. Dewald, P L. Sims, L M. White

IGC Proceedings (1977-2023)

The Woodward Flail-Vac Seed Stripper was developed and tested in Woodward County, Oklahoma during 1980-82. Since its introduction we estimate that more than 500 strippers are now used to harvest the majority of seed used to establish over one million ha of Old World bluestem (OWB) grasses. Recent progress includes manufacture of units from aluminum with 40% less weight, and modifications to allow for multiple harvests. Lower brush rotation speeds resulted in a higher quality product and were less destructive lo immature seed heads, A 25 mm increase in brush diameter and· a redesigned shroud increased the air flow and …


Mechanical Harvesting And Processing Of Temperate Zone And Tropical Pasture Seed, J M. Hopkinson, P.T P. Clifford 2024 Queensland Department of Primary Industries

Mechanical Harvesting And Processing Of Temperate Zone And Tropical Pasture Seed, J M. Hopkinson, P.T P. Clifford

IGC Proceedings (1977-2023)

Temperate zone herbage seed harvesting continues to evolve round combine•harvesters designed principally for large-seeded grain and pulse crops. Most research emphasis has been placed on increasing efficiency of systems for presenting the crop to the auger platform. Timing of harvest, precutting treatment, cutting and pickup alternatives including airblast assistance vary in relation to species and environmental conditions. With the development of drying-cooling systems considerable advantages in the harvesting and processing of grass seed have occurred. An understanding of the range and use of seed cleaning equipment available to meet purity standards is given, along with additional options to meet end.user …


Harvesting And Processing Techniques Of Tropical Grass And Legume Seeds For Smallfarmers, Lumyai Kowithayakorn, Chaisang Phaikaew 2024 Khon Kaen University

Harvesting And Processing Techniques Of Tropical Grass And Legume Seeds For Smallfarmers, Lumyai Kowithayakorn, Chaisang Phaikaew

IGC Proceedings (1977-2023)

For smallfarmers of forage legumes and grasses in Thailand, manual harvesting and cleaning of leguminous seeds have been widely practised because of cheap and available labour. Tropical grasses produce more seeds than can be harvested; hence it is necessary to find means to improve harvesting and processing techniques in order to obtain high standards of both quality and quantity of seed. The main obstacles could be due to prolonged flowering nnd grain filling periods of individual seedheads resulting in the uneven ripening of seeds at harvest. Premature seeds cause low yields and low quality nt harvests in many species. Flowering …


Effects Of Seedbed Environment Of Germination And Seedling Establishment Of Spiny Hopsage (Grayia Spinosa [Hook.] Moq.), Nancy L. Shaw, Marshall R. Haferkamp 2024 USDA Forest Service

Effects Of Seedbed Environment Of Germination And Seedling Establishment Of Spiny Hopsage (Grayia Spinosa [Hook.] Moq.), Nancy L. Shaw, Marshall R. Haferkamp

IGC Proceedings (1977-2023)

This study exam!ned the influence of seedbed micro-environment on germination and seedling establishment of spiny hopsage (Grayia spinosa (Hook.J Moq.) in the shrub steppe of western North America. Two seed collections were drilled in late autumn, early spring and late spring 1987-88. With low precipitation, seedlings established only from late-autumn plantings (


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