Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca,
2024
Humboldt-University Berlin
Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca, W Nitzche
IGC Proceedings (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 (1997-2023)
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 …
Evaluating White Clover For Resistance To Cylindrocladium Root Rot,
2024
University of Florida
Evaluating White Clover For Resistance To Cylindrocladium Root Rot, D S. Wofford, A Amaya
IGC Proceedings (1997-2023)
A rapid screening technique was developed for use in evaluating white clover (Trifolium repens L.) for resistance to Cylindrocladium root rot incited by Cylindrocladium crotalariae. Culture plates of the fungus were evaluated for number of infective propagules after four weeks of growth on potato dextrose agar, and no differences were detected among plates. Seedlings of ‘Osceola’ white clover were exposed in the greenhouse to four levels of inoculum over a six-week period, with resistance based on percent survival of uninoculated controls. It was shown that suspending 1 culture plate in 100ml of water and rating plants four weeks …
Characterization Of Chilling Sensitivity Of Tropical And Temperate Grasses,
2024
National Grassland Research Institute, Japan
Characterization Of Chilling Sensitivity Of Tropical And Temperate Grasses, M Ebina, K Okumura, H Matsu-Ura, Y Tsurumi
IGC Proceedings (1997-2023)
C16-C18 fatty acid composition of some lipids in several species of temperate and tropical grasses were measured. The fatty acid composition of phosphatidylglycerol (PG) and sulfoquinovosyl diglyceride (SQDG) indicated significant differences between temperate and tropical grasses. Especially the differences of the fatty acid composition of PG were remarkable. The unsaturated fatty acid content of PG in tropical grasses was lower than the contents in temperate grasses. These differences constantly appeared through the year. These differences were caused by the low content of polyunsaturated fatty acids, or the low contents of C18 fatty acids.
Characterization Of Somatic Hybrids Between Festuca Arundinacea And Lolium Multiflorum,
2024
National Grassland Research Institute, Japan
Characterization Of Somatic Hybrids Between Festuca Arundinacea And Lolium Multiflorum, M Fujimori, T Takamizo, K Suginobu
IGC Proceedings (1997-2023)
Metabolically inactivated tall fescue (Festuca arundinacea Schreb.) protoplasts and X-ray irradiated Italian ryegrass (Lolium multiflorum Lam.) protoplasts were electrofused resulting in the regeneration of twenty-six plantlets. Southern blot analysis using three mitochondrial probes and random amplified polymorphic DNA (RAPD) analysis revealed that the regenerants were intergeneric somatic hybrids. All regenerated plants were male sterile and some of them had stamens that exhibited the pistillode appearance.
Selecting Lucerne (Medicago Sativa Complex) For Traits Conferring Adaptation To Grazing,
2024
Instituto Sperimentale per le Colture Foraggere
Selecting Lucerne (Medicago Sativa Complex) For Traits Conferring Adaptation To Grazing, E Piano, L Pecetti, M Romani
IGC Proceedings (1997-2023)
A germplasm collection of the Medicago sativa complex was evaluated to select genotypes possessing traits possibly conferring adaptation to grazing. Deep-crowned plants, either creeping-rooted or rhizomatous, were found with different frequencies, in all “taxonomic” groups examined. Although belonging to subsp. sativa, “mielga” wild populations from Spain were closer to subsp. falcata for morpho-physiological traits. Deep-crowned plants could be categorised into four top-growth models, to which corresponded a fairly distinct underground morphology: three were rhizomatous and one creeping-rooted. Cultivars selected for creeping-rootedness did not outyield rhizomatous populations of subsp. x varia which, in turn, had better spreading ability. In a …
Selection For Seed Size And Coleoptile Length In Timothy (Phleum Pratense L.),
2024
Svalöf Weibull, Sweden
Selection For Seed Size And Coleoptile Length In Timothy (Phleum Pratense L.), Hans Arne Jonsson
IGC Proceedings (1997-2023)
The intention of this study was to show the effect of selection for seed weight and coleoptile length on morphology and agronomically important characters in timothy (Phleum pratense L.). Two cycles of selection increased the seed weight as well as the length of coleoptile and root. The emergence from deep sowing in sand and in the field were insignificantly increased, whereas the percentage stand and the dry matter yield were decreased, albeit insignificantly. Inbreeding and linkage effects were considered possible causes for this.
Differential Energy Allocation Among 15 New Guineagrass (Panicum Maximum Jacq.) Hybrids,
2024
State University of Campinas, Brazil
Differential Energy Allocation Among 15 New Guineagrass (Panicum Maximum Jacq.) Hybrids, J A. Usberti Jr, R Usberti, R S. Paterniani
IGC Proceedings (1997-2023)
The main aim of this research work was to determine trends of energy allocation among newly developed guineagrass (Panicum maximum Jacq) hybrids, ranging from very-early to late-flowering genotypes. Besides the flowering cycle, eight phenological and two seed quality traits were scored in a greenhouse randomized complete block experiment including plant height (PH), reproductive tiller number/overall tiller number (RTN/OTN), panicle number/reproductive tiller (PN/RT), leaf length (LL), leaf width (LW), panicle length (PL), fresh weight (FW), dry weight (DW), number of seeds/gram (NS/G) and seed sample physical purity (SPP). Very-early and early-flowering hybrids consistently showed the highest correlations values between flowering …
Improvement Of Forage Quality By Means Of Biotechnology: Stable Transformation Of Warm-Season Grasses By Particle Bombardment,
2024
Miyazaki University, Japan
Improvement Of Forage Quality By Means Of Biotechnology: Stable Transformation Of Warm-Season Grasses By Particle Bombardment, C Yuge, R Akashi, O Kawamura
IGC Proceedings (1997-2023)
We have used a simple and inexpensive, self-built particle acceleration apparatus for direct delivery of DNA to cultured cells of warm-season grasses. High levels of transient expression of the b-glucuronidase gene were obtained following bombardment of embryogenic suspension cells and calli of bahiagrass (Paspalum notatum Flügge) and dallisgrass (Paspalum dilatatum Poir). Furthermore, stable transformed calli of both species have been obtained using this simple particle gun.
Transformation In Lotus Corniculatus: Towards Low-Lignin Pasture Through Antisense Rna,
2024
Miyazaki University
Transformation In Lotus Corniculatus: Towards Low-Lignin Pasture Through Antisense Rna, R Akashi, T Uchiyama, Y Sakatani, O Kawamura
IGC Proceedings (1997-2023)
We have developed a rapid and reproducible transformation system for bird’s-foot trefoil (Lotus corniculatus L.) by using Agrobacterium-mediated T-DNA transfer and the incorporation of the antisense gene for cinnamyl alcohol dehydrogenase (CAD) from Aralia cordata into Lotus for lignin reduction. The presence of the transferred antisense gene in regenerated plants has been confirmed by PCR analysis.
Possibility Of Selection For Mineral Concentration In Orchardgrass By X-Ray Microanalysis,
2024
Iwate University
Possibility Of Selection For Mineral Concentration In Orchardgrass By X-Ray Microanalysis, S Saiga, Y Nishimura, K Izumi
IGC Proceedings (1997-2023)
To assess the ability of X-ray microanalysis for screening breeding populations of orchardgrass in mineral concentration, correlations between chemical and X-ray analysis were investigated. Six orchardgrass plants with high- and low-Mg concentrations were examined for three harvest dates in 1995. The samples were separated into leaf blade, leaf sheath, culm and head. Mg concentration in leaf and head were higher than in sheath and in culm. P concentration was highest in the head, and lowest in the sheath. Correlations between chemical and X-ray analysis were r=0.692***, 0.526***, 0.252* and 0.562*** for Mg, Ca, K and P, respectively. Correlation coefficients between …
Aluminum Tolerance Qtl In Diploid Alfalfa,
2024
University of Georgia
Aluminum Tolerance Qtl In Diploid Alfalfa, M K. Sledge, J H. Bouton, J Tamulonis, W A. Parrot, G Kochert
IGC Proceedings (1997-2023)
Aluminum (Al) toxicity associated with acid soils greatly inhibits alfalfa (Medicago sativa L.) productivity throughout much of the world’s major grassland areas. In this paper, we report the identification of quantitative trait loci (QTL) controlling aluminum tolerance in diploid alfalfa (Medicago sativa L). An in vitro callus growth bioassay was used to select aluminum tolerant and aluminum sensitive parents, and to screen an F2 population for aluminum tolerance. Fifty-eight cDNA probes were mapped to nine linkage groups, and the F2 genotypic classes were contrasted with means from the callus growth bioassay using ANOVA. We also used Mapmaker-QTL to …
Selecting Acid-Soil Tolerant White Clover,
2024
USDA, Agricultural Research Service
Selecting Acid-Soil Tolerant White Clover, P W. Voigt, D R. Morris
IGC Proceedings (1997-2023)
A two-stage, tandem, recurrent-selection program is proposed to improve acid-soil tolerance of white clover, Trifolium repens L. In stage one, we evaluate root growth of very young seedlings, grown in an highly-acid Al toxic soil. Although the relationship between the acid-soil response of very young seedlings and that of mature white clover is unknown, the failure of white clover to become established on a highly-acid, Al-toxic soil suggests that establishment is a critical stage of plant development on such soils. In stage two we reevaluate genotypes selected in stage one, in a small-pot study at two lime levels, to separate …
Lodging Resistance Evaluation In Lolium Multiflorum,
2024
Hokuriku Agricultural Experiment Station, Japan
Lodging Resistance Evaluation In Lolium Multiflorum, Katsuo Egara, Kazuhiro Tase, Makoto Kobayashi, Hiroki Fujii
IGC Proceedings (1997-2023)
The objective of this study was to develop a simple technique to evaluate lodging resistance in Italian ryegrass (Lolium multiflorum) for genetic improvement. Significant relationships were recognized between the pushing resistance index and actual lodging degree (ALD), and between the breaking resistance index and ALD, at the 0.1 and 5 percent levels, respectively.
