Regulation Of Apomixis In Buffelgrass,
2025
USDA, Agricultural Research Service
Regulation Of Apomixis In Buffelgrass, D L. Gustine, R T. Sherwood, I Gounaris
IGC Proceedings (1977-2023)
The apomixis program at the Pasture Laboratory has the long-term objective of finding procedures to manipulate the type of embryo sac which develops in crop species. We would like to induce at will, formation of functional apomictic embryo sacs in obligately sexual species such as maize and wheat, and to induce sexual reproduction in obligate apomicts, such as dallisgrass. The benefits of this capability for plant breeding would be enormous : 1) desirable characteristics could be reproduced over generations in normally sexual genotypes through induced apomixis and 2) genetic variability in apomictic genotypes could be unlocked through sexual crosses. Angiosperms …
Cytological And Histological Mechanisms Of 2n Pollen Formation In Hybrid Napier Grass,
2025
Taiwan Livestock Research Institute
Cytological And Histological Mechanisms Of 2n Pollen Formation In Hybrid Napier Grass, Y K. Cheng, K T. Lo, Y S. Sheng
IGC Proceedings (1977-2023)
Hybrid pennisetum is an interspecific hybrid between pearl millet (Pennisetum americanum) and napier grass (P. purpureum). The combing of good characteristics of these two species by hybridization was reported (Cheng, 1984). The hybrids are triploid, 2n = 21, and propagated vegetatively. Thus a fertile hybrid would offer opportunities for seed production and forage improvement through hybridization. 2n gametes has been used recently as an alternative method to chemical treatments in a breeding program. The objectives of this investigation were to search for triploid hybrid pennisetum which would produce 2n pollen and to determine the cytological and histological origin of …
Apomixis And Sexuality In Brachiaria Decumbens Stapf.,
2025
EMBRAPA
Apomixis And Sexuality In Brachiaria Decumbens Stapf., C B. Do Valle, Y H. Savidan, L Jank
IGC Proceedings (1977-2023)
Brachiaria decumbens Stapf is a perennial tropical forage grass, native to east African savannas. It was introduced to Brazil in the 1960's and is now widely cultivated over 30 million hectares in Central Brazil alone. The two commercial varieties are apomictic tetraploids (2n = 4x = 36), producing uniform progeny, and were selected for their high dry matter production and persistence on poor acid soils. They lack, however, resistance to spittlebugs (Deois spp., Zulia spp., Aeneolania spp.) and produce forage of low nutritive value, especially during the dry winter months. The absence of natural variability associated to apomictic reproduction has …
Amelioration De La Qualite Du Fourrage Chez La Fetuque Elevee (Festuca Arundinacea Schreb.),
2025
RAGT
Amelioration De La Qualite Du Fourrage Chez La Fetuque Elevee (Festuca Arundinacea Schreb.), W Pietraszek, J F. Chosson
IGC Proceedings (1977-2023)
Tres interessante dans nos climats pour son rendement et sa rusticite, la Fetuque elevee demande toutefois, pour etre davantage utilisee, qu'un effort de selection soit fait pour ameliorer sa qualite. Celle-ci est essentiellement determinee par l'appetibilite, l'ingestibilite et Ia digestibilite qui ne peuvent etre mesurees directement que par des troupeaux d'animaux. Leur mesure implique que !'on dispose d'une quantite importante de materiel vegetal et de plus le maintien et la manipulation des animaux sont lourds et couteux. Le selectionneur devrait done pouvoir disposer d'autres criteres, indirects, pour pouvoir estimer Ia qualite de son materiel vegetal dans Jes premiers stades du …
Using Diverse Species To Improve Quality And Yield In The Pennisteum Genus,
2025
USDA, Agricultural Research Service
Using Diverse Species To Improve Quality And Yield In The Pennisteum Genus, W W. Hanna, M Dujardin, W G. Monson
IGC Proceedings (1977-2023)
Pearl millet, Pennisetum glaucum (L.) R. Br., and napiergrass, P. purpureum Schum., are two of the major forage producing Pennisetum species in the tropics and subtropics. Pearl millet is known for its high quality forage and significant progress has been made in developing improved cultivars (Hanna, et al., 1988). Napiergrass has been successfully crossed with pearl millet to produce high quality and high yielding perennial interspecific (PMN) forage hybrids (Hanna and Monson, 1980 and Muldoon and Pearson, 1979). A germplasm evaluation program and an interspecific hybridization program at Tifton, GA (Hanna and Dujardin, 1985) has resulted in the identification of …
Forage Yield And Quality Of Orchardgrass And Tall Fescue Under Simulated Acid Precipitation,
2025
University of Tennessee
Forage Yield And Quality Of Orchardgrass And Tall Fescue Under Simulated Acid Precipitation, J H. Reynolds, J D. Wolt
IGC Proceedings (1977-2023)
Cool-season forage grasses have received less attention than other crops with regard to their sensitivity to acid precipitation even though they are especially well-adapted to portions of the eastern U.S.A. where acid precipitation with a pH less than 4.5 has been documented. Tall fescue (Festuca arundinacea Schreb.) is perhaps the most widely grown cool-season grass in the transition zone of the eastern U.S.A. where it occupies from 12 to 14 million hectares. Orchardgrass (Dactylis glomerata L.) is also widely grown in the eastern U.S.A. Workers in Oregon, such as Cohen et al., 1982, have found few effects on forage yield …
Selection Des Graminees Fourrageres Pour La Qualite: Des Criteres Bases Sur Des References Avec Animaux, M Gillet, J Scehovic, M Marton, L Huguet
IGC Proceedings (1977-2023)
La selection des fourrages pour la qualite exige l'utilisation de criteres indirects. Ceux-ci devraient etre etablis par correlation avec des criteres mesures sur animaux: Cela necessite un nombre suffisant de genotypes de qualite differente. 11 faut done que la selection pour la qualite ait deja en partie reussi. A defaut, les selectionneurs utilisent souvent des correlations etablies en faisant varier le stade de la plante. Mais sont-elles valables pour comparer des genotypes a stade egal? Ils utilisent aussi les preferences des animaux (« appetibilite ») car cela permet de comparer plusieurs genotypes avec un seul lot d'animaux (Jadas-Hecart, 1982; Gillet …
Variability For Mineral Concentrations Contained In High-Digestible Cell Fractions In Orchardgrass,
2025
Iwate University
Variability For Mineral Concentrations Contained In High-Digestible Cell Fractions In Orchardgrass, S Saiga, H Yoneya, K Iwane, K Watanabe
IGC Proceedings (1977-2023)
Metabolic disorders of ruminants including grass tetany are associated with mineral imbalances of forage. Powell et al. (1978) found that lambs on tall fescue utilized Ca, P, and Mg less efficiently although the concentrations were rather higher than in the other grasses. As there are large differences in characteristics among orchardgrass (Dactylis glomerata L.) cultivars, the efficiency of minerals also must differ in different cultivars. For one reason, it is considered that the efficiency to ruminants is due to the rate contained in digestible cell fraction. The objectives of this study were to determine seasonal change of cell fractions, …
The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia,
2025
AFRC/IGAP
The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia, G Moseley, D M. Baker, D H. Hides
IGC Proceedings (1977-2023)
Hypomagnesaemia continues to cause serious economic losses in grazing livestock and recent evidence suggests that its incidence may be increasing. The disease is characterised by a drop in the concentration of magnesium in extracellular fluid and occurs in two forms, chronic and acute. Both forms give rise to classical clinical symptoms which may either result in death or drastically reduced levels of production. The body does not contain a major source of labile magnesium nor does it have a homeostatic mechanism for controlling the level of magnesium in extracellular fluid. The maintainance of normal levels therefore depends almost entirely on …
The Breeding Of Pasture Varieties Of Alfalfa (Medicago Sativa),
2025
All Union Fodder Research Institute
The Breeding Of Pasture Varieties Of Alfalfa (Medicago Sativa), J M. Piskovatsky, V A. Katov, G V. Stepanova
IGC Proceedings (1977-2023)
The work of developing new pasture varieties of alfalfa has been conducted in the All-Union Fodder Research Institute from 1975 onwards. The pasture varieties must be persistent under grazing, and must have a high competitive ability in mixtures with grasses : meadow fescue, timothy and others.
Evaluation And Selection Of The Salt-Tolerant Alfalfa,
2025
Chinese Academy of Agricultural Sciences
Evaluation And Selection Of The Salt-Tolerant Alfalfa, Geng Huazhu
IGC Proceedings (1977-2023)
Alfalfa (Medicago sativa) as a good forage has b��en popularly cultivated for a long time in China. Now it is mainly distributed in the north of the Yangtse River, and covers about 1.3 million hectares in the 14 provinces and regions. It can be planted in the saline-alkali areas, accept alluvial plains and hill regions, for instance, the North of Jiangsu, East of Hebei, North-west of Shandong and Xingjiang. The alfalfa is successfully used in improving and utilizing the saline-alkali soils for developing animal husbandry in the Gangzhou District of Hebei Province, where its planting area is increasing rapidly, …
Use Of New Methods For Grass And Legume Breeding In Western Region Of The Soviet Union,
2025
Lithuanian Agricultural Research Institute
Use Of New Methods For Grass And Legume Breeding In Western Region Of The Soviet Union, R Dapkus
IGC Proceedings (1977-2023)
The climatic conditions of the Western region of the Soviet Union are favourable for grassland production which provides the major part of forage for livestock nutrition. In raising grassland productivity, new varieties play an important role. Adapted varieties with high yield potential must be used. For developing such varieties, the Fodder Crops Breeding Centre fbr the Western region of the Soviet Union was established at the Lituanian Agricultural Research Institute in 1972 on the basis of experience since 1922, when selection of herbage species was initiated there. During the past twenty years, breeding work has progressed rapidly. At present, breeding …
Cool Season Grazing Of Winter-Active Lucernes,
2025
Lincoln College
Cool Season Grazing Of Winter-Active Lucernes, J.G H. White, W J. Lucas
IGC Proceedings (1977-2023)
In New Zealand, lucerne (Medicago sativa L.) is commonly grazed with sheep for much of the year, but winter production is low and alternative, higher-cost feeds need to be provided. However, in most lucerne-growing areas, winters are relatively mild (Lincoln June-August mean temperature 6.2°C), and the recent release of cool-season active cultivars has resulted in considerable farmer interest in winter grazing of lucerne. Standard winter dormant cultivars such as Wairau are normally grazed once in early June for aphid control (Smallfield et al., 1980), then remain ungrazed for at least three months. Coolseason active cultivars are known to produce …
Improvement Of Season Growth And Resistance To Crown Rust Of Tall Fescue Through Hybridization Between Mediterranean Populations And Adapted Cultivars In Japan,
2025
Kyushu National Agricultural Experiment Station
Improvement Of Season Growth And Resistance To Crown Rust Of Tall Fescue Through Hybridization Between Mediterranean Populations And Adapted Cultivars In Japan, Y Ueyama, S Sato
IGC Proceedings (1977-2023)
Since tall fescue (Festuca arundinacea, Schreb.) is one of the temperate grass species which have good heat tolerance, it is mainly used in grasslands established throughout southwestern Japan where it is hot and humid in summer and mild in winter. The cultivars which have good adaptability to the Japanese condition mainly originated from European or North American populations. Mediterranean populations of tall fescue have good growth potential under the low temperature and short day conditions (Evans et al., 1973) and high levels of crown rust resistance (Wofford et al., 1982). But, the grass species distributed in Mediterranean area are known …
Progress And Prospects For Combining Resistance To Meloidogyne Javanica (Grass Root-Knot Nematode) With Improved Forage Yield In Chloris Gayana (Rhodes Grass),
2025
Grassland Research Station, Zimbabwe
Progress And Prospects For Combining Resistance To Meloidogyne Javanica (Grass Root-Knot Nematode) With Improved Forage Yield In Chloris Gayana (Rhodes Grass), P A. York
IGC Proceedings (1977-2023)
Meloidogyne javanica, root-knot nematode, has been described as the most serious pest of crops in Central Africa (Daulton & Curtis, 1963). It is widespread in Zimbabwe and very damaging to susceptible crops, particularly tobacco. Good tobacco growers use integrated control measures, sterilizing seed-beds with methyl bromide, lands with ethylene dibromide (EDB) and resting with three or four year Katambora Rhodes grass pastures. Katambora controls M. javanica, improves soil structure, reduces erosion and provides cattle fodder as grazing and poor quality hay. A breeding project has been established in Zimbabwe to combine the better forage production of tetraploid Rhodes grass strains …
Intermediate White Clover - A Model For Clover Persistence On The Gulf Coast In Usa,
2025
Texas Agricultural Experiment Station
Intermediate White Clover - A Model For Clover Persistence On The Gulf Coast In Usa, G W. Evers
IGC Proceedings (1977-2023)
The Gulf Coast region of the USA is classified as subtropical (Rotar and Kretschmer, 1985). Persistence of perennial temperate legumes in this area is poor because of climatic, management, insect and disease factors (Kendall and Stringer, 1985). Frosts during the short-day season limit flowering and seed set of perennial tropical legumes (Rotar and Kretschmer, 1985; Evers, 1973). Annual Trifolium spp. or perennial species which act as annuals, are used in the area (Evers, 1984). The major limitation of annual legumes is dependable reseeding each fall. Although classified as a perennial, Hollowell (1966) has suggested that white clover (Trifolium repens …
Productivity Of Selected High And Low Leaf Area Expansion Festuca Arundinacea Strains,
2025
University of Missouri
Productivity Of Selected High And Low Leaf Area Expansion Festuca Arundinacea Strains, D A. Sleper, C J. Nelson
IGC Proceedings (1977-2023)
A selection program was initiated in 1975 to select for high (H) - and low (L)-LAER in a broad-based population of tall fescue ( Festuca arundinacea Schreb.) to improve vegetative herbage yield (Nelson and Sleper, 1983). Response to divergent selection was linear and symmetric for five cycles (Reeder et al., 1984). Mean increase in selecting for H-LAER was greater than 10 % per cycle ; a mean decrease of more than 8 % per cycle was observed when selecting for L-LAER. Nelson et al. (1977) and Reeder et al. (1984) showed that HLAER genotypes had wider leaves and higher leaf …
Effects Of Acid Soil Selection On Agronomically Important Traits In Alfalfa,
2025
University of Georgia
Effects Of Acid Soil Selection On Agronomically Important Traits In Alfalfa, J H. Bouton, D E. Radcliffe
IGC Proceedings (1977-2023)
Acid soils and their related toxicities are found in every continent of the world. Since liming and fertilization rarely overcome subsoil acidity, poor rooting usually results when growing sensitive legumes such as alfalfa ( Medicago sativa L.). Subsoil liming increased alfalfa yield 46 % over conventionally limed controls indicating deeper rooting achieved through an ability to overcome subsoil toxicity significantly enhanced stand life and productivity (Bouton et al., 1986). If acid soil tolerance could be incorporated into new multiple-pest resistant cul ti vars without loss of their desirable traits, farmers may realize the benefits of any new alfalfa cultivar. The …
Improvement Of Winter, Early Spring Growth In Temperate Pasture Grasses,
2025
Agricultural Research and Veterinary Centre
Improvement Of Winter, Early Spring Growth In Temperate Pasture Grasses, D R. Kemp, M O. Humphreys, C F. Eagles
IGC Proceedings (1977-2023)
Improvement of pasture growth during winter and early spring in temperate regions has been a major goal of many grass breeding programmes. Improvements have been made by selecting for increased yield in early spring, although the basis of these yield improvements is poorly understood. The increase, measured as vegetative components of yield, has been interpreted as improved efficiency of growth at low temperatures. However, there is evidence that increased grass growth rates during late winter and early spring are associated with reproductive development (Kemp, 1985, 1988). In this paper we review physiological evidence for growth differences between genotypes during winter …
Kikuyu Grass Improvement For Grazing And Amenity Uses,
2025
MAFTech, NZ
Kikuyu Grass Improvement For Grazing And Amenity Uses, G J. Piggot, H M. Morgan
IGC Proceedings (1977-2023)
Kikuyu grass (Pennisetum clandestinum) is a stoloniferous perennial important in warm-temperate and sub-tropical regions for grazing, erosion control, or amenity uses. Genetic improvement and the registration of cultivars has occurred in Australia (Wilson, 1975; Anon., 1983a, 1983b). Evaluation in New Zealand of this material has investigated the potential for further improvement of kikuyu grass for grazing and amenity uses. In this work, plants considered suitable for selection as a « grazing» type have erectness, large leaves, low stolons number, and high yield. «Amenity» types have fines leaves, thin stolons, low stolon number, and a prostrate and dense habit.
