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 …
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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 (1977-2023)
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.
Mechanistic Modelling Of Grassland Energy Balance,
2024
Lincoln University, New Zealand
Mechanistic Modelling Of Grassland Energy Balance, G D. Buchan, B Main, B A. Mckenzie
IGC Proceedings (1977-2023)
No abstract provided.
Radiation Balance And Production Of Forage Crops In A Mediterranean Region,
2024
Instituto Sperimentale Agronomico, Italy
Radiation Balance And Production Of Forage Crops In A Mediterranean Region, G Rana, F Fornaro
IGC Proceedings (1977-2023)
This study is devoted to measure the radiation use efficiency (RUE) and the extinction light coefficient (k) of a sainfoin crop, cultivated in a site of Southern Italy. The same parameters are measured also for the global solar radiation (in this case kg and RUEg, respectively). The crop was maintened in well watered conditions and the measures were carried out during four cut cycles, one during 1994 and three during 1995. Transmitted, incident, soil and canopy reflected radiations were measured continously during the growth season. The results were given a mean of 2.61 and 1.2 …
Use Of Biomass From Reed Canary Grass (Phalaris Arundinacea) As Raw Material For Production Of Paper Pulp And Fuel,
2024
Svalof Weibull, Sweden
Use Of Biomass From Reed Canary Grass (Phalaris Arundinacea) As Raw Material For Production Of Paper Pulp And Fuel, B Andersson, E Lindvall
IGC Proceedings (1977-2023)
Reed canary grass (Phalaris arundinacea) has been investigated as a potential industrial crop in Sweden and other European countries. Reed canary grass (RCG) can be used as raw-material for paper pulp or as biofuel for combustion. A new harvest method, the delayed harvesting system, was developed which makes it possible to get dry, ready to store, material. The method reduces cost and improves quality of the product. The use of RCG as an industrial crop requires a completely different quality compared to forage. The important part is the cellulose while protein and mineral nutrients are disturbing the process …
Tall Tropical Grasses And Leucaena As Energy Crops For Lower South Usa,
2024
University of Florida
Tall Tropical Grasses And Leucaena As Energy Crops For Lower South Usa, G M. Prine, K R. Woodard
IGC Proceedings (1977-2023)
The tropical leguminous shrub/tree, leucaena (Leucaena spp. mainly leucocephala), and perennial tropical tall grasses such as elephantgrass (Pennisetum purpureum), sugarcane, and energycane (Saccharum spp.) are well adapted to the long growing seasons and high rainfall of humid lower South. In much of the area the topgrowth is killed by frost during winter and plants regenerate from underground parts in spring. Selected accessions from a duplicated 373 accession leucaena nursery had an average annual woody stem dry matter production of 31.4 Mg ha-1 and four seasons growth of 78.9 Mg ha-1. The tall perennial grasses have …
Energy Balance Of Different Intensive Forage Cropping Systems In Northern Italy,
2024
Instituto Sperimentale per la Colture Foraggere, Italy
Energy Balance Of Different Intensive Forage Cropping Systems In Northern Italy, M Onofrii, C Tomasoni, L Borrelli, L Bechini
IGC Proceedings (1977-2023)
Five forage crop rotations at two intensification levels have been compared using energy analysis, to have an integrated view on the systems under study. Inputs required by the five rotations ranged from 33 to 72 GJ•ha-1•yr1• Outputs from cropping systems ranged from41 to 153 GJ•ha-1•yr1 and output/input ratios from 1,25 to 2,13. The most efficient rotations in terms of net energy production efficiency have been characterised by reduced length and presence of maize and catch-crops. Low intensification level has caused higher efficiency in three rotations.
