Inbreeding Of Some Populations In The Genus Agrostis L.,
2024
Center for Forage Crops, Yugoslavia
Inbreeding Of Some Populations In The Genus Agrostis L., Zorica Tomic, Gordana Surlan Momirovic, Dusica Delic, S Ostojic
IGC Proceedings (1977-2023)
This work presents some properties on produced inbred lines of the 5 best populations of 4 species of Agrostis for breeding purposes. The cultivars of forage grasses should meet a given aim for selection, which is the increasing dry matter and quality. The populations used in this research were the best ones for morphological and productive properties from a previous study. By the process of selfing there have been produced S1 offsprings which appeared to be quite superior in relation to open pollinated offspring from the mother plants. The obtained results were processed by multiple range regression analyses. According to …
The Effect Of Abscisic Acid On The Freezing Tolerance In Lolium Temulentum L.,
2024
Hokuriku National Agricultural Experiment Station
The Effect Of Abscisic Acid On The Freezing Tolerance In Lolium Temulentum L., K Tase, H Fujii
IGC Proceedings (1977-2023)
This study was conducted to clarify the effect of abscisic acid (ABA) on the development of freezing tolerance in Lolium temulentum L. We compared the changes of freezing tolerance and endogenous ABA content by the ABA treatment with those by the hardening treatment. Exogenous ABA applications (7.5 x 10-5 M) increased freezing tolerance, but did not completely substitute for the hardening process. This treatment resulted in great increase in endogenous ABA content, as compared with the control or the hardening treatment. Since the relationship between endogenous ABA content and freezing tolerance was not parallel, it is considered that freezing tolerance …
Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation,
2024
Institute of Grassland and Environmental Research, UK
Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation, A H. Marshall, T P.T Michaelson-Yeates, M Meredith, D H. Hides
IGC Proceedings (1977-2023)
Interspecific hybridization between white clover (Trifolium repens L.) and ball clover (T.nigrescens) and Caucasian clover (T.ambiguum) is a means of improving the reproductive growth and persistency of T.repens. F1 hybrids between T.repens and T.nigrescens were produced without ovule culture and confirmed as true hybrids by chromosome counts, isoenzyme analysis and leaf markers. Their growth habit was generally intermediate between the two parents. After backcrossing to T.repens the BC1 and BC2 hybrids had more of the characteristics associated with T.repens though they retained some of the greater reproductive growth of …
Colchicine-Doubling Of Germinating Seedlings Of Interspecific Wildrye Hybrids,
2024
Utah State University
Colchicine-Doubling Of Germinating Seedlings Of Interspecific Wildrye Hybrids, T A. Jones, D C. Nielson, H Jaussi
IGC Proceedings (1977-2023)
Colchicine has usually been applied to sterile clones of interspecific grass hybrids to restore fertility. However, when hybrids are partially fertile, colchicine can be applied to germinating seedlings. Four populations of Basin wildrye (Leymus cinereus) X beardless wildrye (L. triticoides) were treated with a 0.2% colchicine solution to double chromosome number from 4x=28 to 8x=56. Doubling percentage was 28, 33, 42, and 44% of all root-tips examined for the four populations. When plants without doubled sectors were discarded, doubling percentage increased to 56, 68, 78, and 78%. Plants with doubled sectors have been placed in crossing blocks …
Wayne E. Sabbe Arkansas Soil Fertility Studies 2023,
2024
University of Arkansas, Fayetteville
Wayne E. Sabbe Arkansas Soil Fertility Studies 2023, Nathan A. Slaton
Arkansas Agricultural Experiment Station Research Series
Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.
Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments,
2024
Central Research Institute for Field Crops, Turkey
Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim
IGC Proceedings (1977-2023)
The Central Highlands (CH) of Turkey are characterized by cold winters and dry summers. Under these extreme air temperatures, forage crops are still underexploited as a part of crop rotations. Half of the total vetch hectarage in Turkey is in the CH, and farmers still use the local cultivars that have good adaptability but low yield potential. Therefore, with the aim of identifying and improving the annual forage legume species for the cold and dry environment of the CH, research work was carried out during the 1993/94 and 1994/ 95 crop seasons. Initial results showed that Hungarian vetch (Vicia …
Use Of The Grazing Animal In Forage Breeding,
2024
University of Georgia
Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates
IGC Proceedings (1977-2023)
The objective of these studies was to determine, in the context of a forage breeding program, the effect of cattle grazing on survival of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Different cultivars of each species were compared in grazed and ungrazed areas. Results consistently demonstrated that grazing reduced plant stands when compared to ungrazed conditions for each species tested. In alfalfa, however, cultivars developed for grazing tolerance showed much better grazing survival. Infection with the fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, likewise substantially increased grazing survival in …
Study Of Genotype X Environment Interaction In Alfalfa Forage Yield,
2024
Agriculture and Agri-Food Canada
Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen
IGC Proceedings (1977-2023)
The response of alfalfa (Medicago sativa L.) forage yield to eight Alberta test sites was studied for the 1990 and 1991 production years. Cluster analysis was used to group locations and cultivars. Analyses of variances indicated genotype x environment (location) interaction for the first cut yield, the total yield and the difference between first and second cut yields. The Brooks, Bow Island (irrigation), Bow Island (dryland) and Provost locations always clustered together indicating that three of these four test sites may be eliminated without sacrificing reliability.
Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment,
2024
University of Perugia
Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment, D Rosellini, F Veronesi, F Lorenzetti
IGC Proceedings (1977-2023)
Cultivar development in alfalfa relies on heterosis, that has been mainly exploited by intercrossing selected clones from diverse gemplasm sources; an alternative way was proposed, based on developing double cross cultivars obtained by crossing clones selected for self-sterility, propagated by somatic seed. A different breeding strategy was recently emphasized based on population improvement through inbreeding and recurrent selection; in this case, self-sterility would be selected against. If self-sterility is determined by genetic load, the second strategy should be preferred, and selecting for self-fertility may bring about positive correlated responses for forage yield. Divergent selection for self-fertility was applied in a …
Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass,
2024
Taiwan Livestock Research Institute, Taiwan
Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass, C S. Chen, S M. Wang, Y K. Cheng
IGC Proceedings (1977-2023)
Pangolagrass cv. A254, a sterile strain, is one of Taiwan's major forage sources but recently has faced serious disease problems. Tissue culture was expected to generate variations in the breeding program of pangolagrass. The purpose of this study is to examine the somaclonal variation of regenerated plants by means of phenotypic characters survey and RAPD analysis. After long-term suspension culture and EMS mutagenesis, many regenerated plants with morphological variations have been found. Among the regenerants, 10 clones with obviously different characteristics were selected for further studies. Nine of them showed significant differences in morphological trains as compared to A254. By …
Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum),
2024
USDA, Agricultural Research Service
Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum), B L. Burson, M A. Hussey
IGC Proceedings (1977-2023)
Common dallisgrass, Paspalum dilatatum Poir., an important warm season forage grass, is an obligate apomict with 50 chromosomes which associate as 20 bivalents and 10 univalents during meiosis. Because efforts to improve the grass have not been successful, a phylogenetic investigation was initiated to identify the progenitors of common dallisgrass in an effort to circumvent the apomictic barrier to improvement. The genomic composition has been determined for four dallisgrass biotypes: yellow-anthered (2n=4x=40) IIJJ; common (2n=5x=50) IIJJX; Uruguayan (2n=6x=60) IIJJXX; and Uruguaiana (2n=6x=60) IIJJXX. While the source of the X genome is unknown, the genes controlling apomixis are on at least …
Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance,
2024
USDA, Agricultural Research Service
Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance, R R. Smith
IGC Proceedings (1977-2023)
Red clover (Trifolium pratense L.), an excellent perennial forage legume, has been considered for many years to be a short-lived, two to three years, forage. Selection for resistance to foliar and root rot diseases and for longevity of stand over the past four decades has improved the persistence of the currently available cultivars. The present studies were conducted to evaluate the progress from selection for longevity and disease resistance. Selection for stand longevity and improved disease resistance has reliably extended the production of red clover into the third and fourth year. Selection for healthy plants in 3- or …
Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca,
2024
Humboldt-University Berlin
Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca, W Nitzche
IGC Proceedings (1977-2023)
Fertile diploid hybrids of Lolium x Festuca -backcrosses were produced by colchicine-treatment without chromosome doubling. The hybrids have new combinations of their characters, not known in the natural species.
Selection For Herbage Yield And Flowering In Ladino White Clover,
2024
INIA La Estanzuela, Uruguay
Selection For Herbage Yield And Flowering In Ladino White Clover, J A. Garcia
IGC Proceedings (1977-2023)
A geno-phenotypic recurrent selection program is being carried out on ladino white clover (Trifolium repens L.) aiming to combine good DM and seed yields. Selection criteria includes plant density, vigor, winter growth, flowering and diseases resistance. The performance of selections in terms of DM yields and seed production was evaluated in separate trials. Two cycles of selection increased flowering by 36% and seed yield by 59%. Preliminary data on herbage yields shows a very good performance of the selected material and suggests the feasibility of combining high DM and seed yields.
Selection For Field Survival Increases Freezing Tolerance In Festulolium,
2024
University of Wisconsin-Madison
Selection For Field Survival Increases Freezing Tolerance In Festulolium, M D. Casler, P G. Pitts, P C. Bilkey, C A. Rose-Fricker
IGC Proceedings (1977-2023)
Festulolium (Festulolium braunii K.A.) is marginally adapted to the north central and northeastern USA and southern Canada. The purpose of this study was to evaluate four festulolium populations selected for field survival under harsh winter conditions for their freezing tolerance in controlled environments. Progenies of all four populations showed some improvement in freezing tolerance compared to their parents. Improvements were dependent on the temperature at which measurements were made and varied among germplasms. Improvements were manifested in both decreased plant mortality and decreased injury to surviving plants. Genetic variation for freezing tolerance appears to be a viable mechanism …
Fitness Of Apomictic And Sexual Buffelgrass Germplasm,
2024
The Texas A&M University
Fitness Of Apomictic And Sexual Buffelgrass Germplasm, M A. Hussey, Yue-Wen Wang, B L. Burson
IGC Proceedings (1977-2023)
Breeding apomictic grasses is based on either the direct selection of apomictic landraces or the hybridization of sexual and apomictic types and selection of apomictic F1 hybrids. Little is known about the potential of sexual hybrids as cultivars in apomictic species. To determine if method of reproduction (MOR) was related to plant vigor, parental, S1, and F1 hybrids of buffelgrass differing in method of reproduction (apomictic or sexual) were established in a common garden in 1994 and 1995. In both years severe inbreeding depression was observed in the S1 progeny as they were shorter, produced less biomass, and had low …
Selection For Nitrogen Use Efficiency In Perennial Ryegrass Using Hydroponics,
2024
DLO-Centre for Plant Breeding and Reproduction Research, The Netherlands
Selection For Nitrogen Use Efficiency In Perennial Ryegrass Using Hydroponics, E N. Van Loo, A.J. P. Van Wijk, O Dolstra, H.J. P. Marvin, C.H. A. Snijders
IGC Proceedings (1977-2023)
A selection method was tested for improving nitrogen use efficiency of perennial ryegrass (Lolium perenne L.) using a hydroponics system that controls the plant nitrogen concentration. Divergent selection for plant production, leaf area increase and dry matter distribution in six segregating populations under limiting nitrogen supply resulted in differences between offspring of upward and downward selections larger than 20 % in most characteristics. Moderately high realized heritabilities were found for some characteristics (up to 0.88). It is concluded that early selection for nitrogen use efficiency is feasible using this hydroponics system.
Development Of A Multicross Cultivars Of Stylosanthes Spp.,
2024
National Beef Cattle Research Center, Brazil
Development Of A Multicross Cultivars Of Stylosanthes Spp., B Grof, C D. Fernandes, C B. Almeida, A V. Dos Santos
IGC Proceedings (1977-2023)
A synthetic population, referred to as multicross, has been developed from an interspecific mixture of Stylosanthes capitata and S.macrocephala germplasm. This basic population evolved in a farming situation subject to uncontrolled, continuous, heavy grazing. Natural selection and systematically programmed intercrossing among anthracnose-resistant Venezuelan and Brazilian genotypes of S.capitata have played major roles in the subsequent development of this heterogeneous population. Eight anthracnose-resistant Venezuelan and two Brazilian accessions of S.capitata were introgressed into the basic population. Genetic diversity was further increased by adding seed of four selected accessions of S. macrocephala to the synthetic which had already included …
Selection Of Stylosanthes Guianensis For The Cerrados Of Brazil,
2024
National Beef Cattle Research Center, Brazil
Selection Of Stylosanthes Guianensis For The Cerrados Of Brazil, B Grof, C D. Fernandes, A V. Dos Santos, C B. Almeida
IGC Proceedings (1977-2023)
Progenies of intervarietal hybrid stylos (Stylosanthes guianensis var.vulgaris x S.guianensis var.pauciflora) with mid-season maturity date (early-and mid-June), high dry matter and seed yields have been identified at the National Beef Cattle Research Center (CNPGC), Campo Grande, MS, Brazil. Dry matter yields of the best selections were comparable to those of the late-flowering control, cv. Mineirão. Several mid-season hybrids produced 150 to 200 kg/ha of seed-inpod and a single plant selection yielded in excess of 300 kg/ha. The high degree of resistance to anthracnose observed in the advanced generations is attributed to the immense genetic diversity of these …
Development Of Red Clover With High Levels Of Resistance To Root-Knot Nematodes,
2024
University of Florida
Development Of Red Clover With High Levels Of Resistance To Root-Knot Nematodes, K H. Quesenberry, R A. Dunn, D E. Moon
IGC Proceedings (1977-2023)
Red clover (Trifolium pratense L.), is grown in many areas of the world, but production in subtropical regions may be limited by susceptibility to root-knot nematodes (Meloidogyne spp.) (RKN). Selection for early vigor in RKN infested soils resulted in moderate RKN tolerance in ‘Cherokee’. However, improved RKN resistance in red clover was needed. Seven additional cycles of greenhouse selection using Cherokee as a base population developed a population (FLMR7) with high RKN resistance. When FLMR7 was infested with M. arenaria, M. hapla, M. incognita, or M. javanica, numbers of galls and egg masses …
