Bromus Stamineus- A Potential New Species For Pastures In Dry Regions Of New Zealand,
2024
Ceres Research Station
Bromus Stamineus- A Potential New Species For Pastures In Dry Regions Of New Zealand, A V. Stewart
IGC Proceedings (1977-2023)
Bromus stamineus Desvaux is a fine-leaved perennial species closely related to prairie grass (B. willdenowil Kunth). It differs primarily by having a greater number of smaller tillers and excellent tolerance to close grazing. Such characteristics provide it with considerable potential in drier east coast districts of New Zealand. The release of the first cultivar of this species, Grasslands Gala grazing brome, is enabling this potential to be developed. Further research is required to determine the precise role of this species.
The Value Of Adapted, Annual Ryegrasses For Subtropical Dairy Production,
2024
Queensland Department of Primary Industries
The Value Of Adapted, Annual Ryegrasses For Subtropical Dairy Production, K F. Lowe, T M. Bowdler, G K. Reason, R J. Moss
IGC Proceedings (1977-2023)
Cutting and grazing experiments were conducted in a subtropical environment to determine whether a relationship existed between differences measured in ryegrass cultivars from cutting experiments and milk production differences under grazing. Differences in dry mauer (OM) production under cutting between the standard annual ryegrass for the subtropics (Grasslands Tama) and a cultivar selected for superior performance under subtropical conditions (Midmar) averaged 31 %, differences in feed on offer under grazing averaged 21 %, while milk production differences averaged 10% in a 2-year study. The results indicate that increases in OM yield measured in cutting experiments will be consistent wlth differences …
Screening Lespedeza Cuneata Accessions For Hypocotyl Elongation,
2024
Auburn University
Screening Lespedeza Cuneata Accessions For Hypocotyl Elongation, J Qiu, J A. Mosjidis
IGC Proceedings (1977-2023)
Poor seedling emergence is one of the major limitations in establishing sericea lespedeza (Lespedeza cuneata (Dumont de Courset) CJ. Don.). The objectives of this study were to screen 2S accessions obtained from the National Plant Germplasm System, USA, for maximum hypocotyl elongation (HE) and to determine the relationship between HE and percentage emergence. Maximum HE of each accession was determined on dark-grown seedlings 9 days after emergence in a growth chamber. Seeds of each accession were planted in the field at depths of 1 and 3 cm in 1990 and 1991. Emergence of 9 accessions (3 with long HE, …
Fertilization Of Unreduced Female Gametes: A Technique For Genetic Enhancement Within The Cenchrus-Pennisteum Agamic Complex,
2024
Texas A&M University
Fertilization Of Unreduced Female Gametes: A Technique For Genetic Enhancement Within The Cenchrus-Pennisteum Agamic Complex, M A. Hussey, E C. Bashaw, K W. Hignight, J Wipff, S L. Hatch
IGC Proceedings (1977-2023)
Genetic enhancement programmes In apomictic species require either the identification of obligate sexual genotypes or facultative apomicts with high levels of sexuality.- Fertilisation of unreduced eggs (2n+n hybridisation) which occurs frequently within agamic complexes has received little attention as a method for breeding apomictic species. This paper describes attempts to obtain 2n+n hybrids within the Cenchrus-Penniseltim agamic complex. Both inter- and intraspecific n+n and 2n+n hybrids have been obtained using facultative accessions of C. ciliaris or P. flaccld11m as female parents. Interspecific 2n+n hybrids, which have been recovered at frequencies approaching 3%, are typically more fertile than interspeclfic n+n hybrids. …
Evaluation Of Dwarf Napiergrass,
2024
USDA, Agricultural Research Service
Evaluation Of Dwarf Napiergrass, W W. Hanna, W G. Monson, G M. Hill
IGC Proceedings (1977-2023)
Napiergrass (Pennisetum purpureum Schum.), a robust perennial bunchgrass with high yield potential, rapidly loses quality and palatability without proper management as it matures. In 1985 and 1986, 2 dwarf napiergrass cultivars (Mott and Tift Nl29) and 2 tall cultivars (Merkeron and Tift N68) were evaluated for yield, quality and agronomic characteristics. Dwarf cultivars yielded about 1/3 as much as tall cultivars. Percentage leaf was 60-76 for dwarf cultivors and 43-46 for tall cultivars. Average In vitro dry matter digestibility (lVDMD) of whole plants was similar among cultivars except for Tift N68 which tended to be lower (605, 594, 610 …
Hybridization Among Atylosia Species,
2024
Indian Grassland and Fodder Research Institute
Hybridization Among Atylosia Species, S N. Tripathi
IGC Proceedings (1977-2023)
Hybridisations among Atyloslaalbicans (twining shrub),A.scarabaeoides species (herbaceous creeper) and A. cajanlfolia (erect shrub) were carried out. The interspecific cross A. albicans x A. scarabaeoides and trispecific cross (F1 of A. albicans x A. Scarabaeoides) x A. Cajanifolia manifest forage potentially through their various morphogenetic types, erect with profuse branching and high leafiness, semi-erect coupled with profuse branching, semi-erect bushy, and spreading with broadleaves. These hybrids possess desirable gene combinations for tolerance, persistence, vigour and productivity which constitute important attributes for their adaptive fitness in tropical grasslands. Although the 3 Atylosia species were morphogenetically divergent from one another, …
Genetic Improvement And Nutritive Value Of Lucerne: Crude Protein Content,
2024
Instituto Sperimentale per le Colture Forragere
Genetic Improvement And Nutritive Value Of Lucerne: Crude Protein Content, P Rotili, G Gnocchi, C Scotti
IGC Proceedings (1977-2023)
Stratigraphical analysis of a lucerne (Medicago saliva L.) stand was made to show the effect of leaf age and health, and of leaf-stem ratio, on crude protein content, These data show that when the analysis was made on stems of the same age and on leaves of the same age, health and physiological state, the variability of this trait is negligible, which makes it very difficult to breed for crude protein content. Nevertheless ii is possible to improve the protein content by selection for physiological trails such as leaf persistence and tolerance of early culling.
Selfing And Competition Applied To Lucerne Breeding And To Variety Constitution,
2024
Instuto Sperimeimentale per le Colture Foraggere
Selfing And Competition Applied To Lucerne Breeding And To Variety Constitution, P Rotili
IGC Proceedings (1977-2023)
The variety constitution process of the forage Crops Institute of Lodi is characterised by: 1) the exploitation of interference effects (competition): 2) the utilisation of a selfing phase; 3) a synthetic variety formula based on parental clones derived by several parental populations, The phenotypic choice of mother plants and the progeny tests are made in dense swards. The research on competition has allowed the formulation of an ideal model of the lucerne (Medicago saliva L.) stand and of the plant ideotype, The ideal model of the lucerne stand is characterised by the synchrony of the individual plants for the physiological …
Progress In White Clover Agronomic Performance Through Breeding,
2024
AgResearch, NZ
Progress In White Clover Agronomic Performance Through Breeding, J R. Caradus
IGC Proceedings (1977-2023)
White clover (Trifolium repens L.) domestication began in the 16th century in Europe. However, it was not until the early 1920s that broad • agronomic groups were recognised, and not until the early 1930s that selections for improved agronomic performance were made within major ecotypes. Since then more than ·230 cullivars and commercial ecotypes have been developed. Data from 4 trials, 2 from Czechoslovakia, l from New Zealand and I from South Africa, were used io determine whether breeding since the 1930s had significantly improved in white clover performance. Cultivars were coded by decade in which they were developed …
Effect Of Method And Intensity Of Selection For Yield In White Clover,
2024
AgResearch, NZ
Effect Of Method And Intensity Of Selection For Yield In White Clover, J R. Caradus, W M. Williams
IGC Proceedings (1977-2023)
The effectiveness of various strategies of selection for yield was tested using high performing white clover (Trifolium repens L.) lines derived from crosses between elite Grasslands Huia genotypes and elite genotypes from introduced germpiasm. There appeared to be no clear advantage of selecting genotypes, at the same intensity of selection, in the top 12.5% of families compared with the top 50% of families, There was a weak trend towards higher yielding progeny with increasing selection intensity. It was more effective to use individual selection within families based on performance rather than family selection, However, this effect was specific to …
Gene Action And Enhanced Progressive Heterosis In Autotetraploid Alfalfa,
2024
AgResearch, NZ
Gene Action And Enhanced Progressive Heterosis In Autotetraploid Alfalfa, D R. Woodfield, E T. Bingham
IGC Proceedings (1977-2023)
Two-allele populations (TAPs) of autotelraploid alfalfa (Medicago sativa L.) were used to evaluate whether progressive heterosis can be enhanced through accumulation of favourable- alleles._ Comparisons involved 4 TAPs per se, and single- and double-crosses produced by hybridising the TAPs, at both the original (OG) and advanced generation (AG) levels. When the different progenies were compared as a percentage of the "Vernal" check, AG crosses exhibited consistent improvements in breeding value over their OG counterparts and also show enhanced progressive heterosis. These improvements occurred despite higher inbreeding levels (decreased heterozygosity) in the AG progenies and indicate that heterosis can be …
Plant Improvement: The Evaluation And Extension Processes,
2024
Queens University- Belfast
Plant Improvement: The Evaluation And Extension Processes, A S. Laidlaw, K.F M. Reed
IGC Proceedings (1977-2023)
Registration and evaluation systems throughout the world range from voluntary registration to compulsory schemes involving assessment of taxonomic and agronomic characteristics. Evaluation can be confined to agronomic tests simulated under grazing management or extended to feeding-value trials. Criteria include adaptation to climate and soils, persistence and seasonal growth, annual dry matter production, resistance to pests and diseases, and association with beneficial organisms. The need for stress (e.g. drought, low nutrients, acidity, salinity, heat or cold) to be given more emphasis in programmes in specific localities is suggested. In developing regions the emphasis is screening a wide range of grasses and …
Achievements And Perspectives In The Breeding Of Forage Grasses And Legumes,
2024
Vanderhave Research
Achievements And Perspectives In The Breeding Of Forage Grasses And Legumes, A.J P. Van Wijk, J G. Boonman, W Rumball
IGC Proceedings (1977-2023)
Successful breeding progrnmmes on forage grasses and legumes have in common that they made seed and plant material of superior genetic and physical quality available to the end-user at competitive prices. This was achieved by government- and privately-funded breeding programmes. A distinction between these two types of breeding organisations is made and discussed. Achievements in various areas are presented and the constraints the breeder is faced with ore given. It is felt that highly advanced genetic designs are not directly applicable, but that progress can continue to be made by applying classical procedures at a greater level of efficiency.
Nutritive Value Of Regrowth Of Pennisetum Parents And Hybrid Progeny,
2024
University of Florida
Nutritive Value Of Regrowth Of Pennisetum Parents And Hybrid Progeny, S C. Schank, D A. Diz, R L. Smith
IGC Proceedings (1977-2023)
Low forage nutritive value of the giant forms of elephantgrass (Pen,1isetum purpureum Schum.) has limited its production In tropical areas. A dwarf cultivar, Motl ·(released In 1988), has given convincing evidence of much higher forage quality. A tall elephantgrass (cv. Kinggrass, USDA PI 300086) was hybridised with Moll. Over 400 lntraspecific hybrids were obtained in 1988 and evaluated. Yield and forage 11utrillve value of the two parents and selected progeny were compared. Dry matter production was measured at 6-week regrowth and 12-week regrowth during 1990. Samples collected were analysed for in vitro digestible organic matter (IVDOM) and crude protein (CP), …
Divergent Selection For Forage Yield Components In Switchgrass,
2024
South Dakota State University
Divergent Selection For Forage Yield Components In Switchgrass, R Bortnem, A Boe, K D. Kephart
IGC Proceedings (1977-2023)
The objective of this study was to evaluate half-sib families of 30 plants each of Summer and Sunburst switchgrass (Panicum virgatum L.) from a divergent selection for forage yield components programme. Highly significant differences were found among families within each cullivar for blade weight, stem weight, sheath weight and blade-to-stem ratio (BSR) at anthesis. The family x year interaction was significant only for BSR for Summer. Highly significant differences were found nmong families from "high" and "low" parents for each of the 4 traits. Genetic variances were higher for Summer than Sunburst for 3 of the 4 traits. Phenotypic …
Alfalfa Stem Architecture Effects On Forage Quality,
2024
South Dakota State University
Alfalfa Stem Architecture Effects On Forage Quality, K D. Kephart, A Boe, R Bortnem
IGC Proceedings (1977-2023)
Forage quality in alfalfa (Medicago sativa L.) may be improved by selection for increased branching to dilute stem bases with less lignified branch tissue. This research was done to determine the effects of selection for branching on growth and forage quality of alfalfa stems. Divergent selection for the mass ratio of aidllary. to main stems (AMR) was done within 2 alfalfa cultivars and tested at 2 locations. High-AMR genotypes had about 16% greater AMR than low-AMR genotypes. Although differences in AMR existed, i11 vitro digestible dry matter (IVDDM) concentration of total stems and stem branches did not differ between …
Assessment Of Freezing Tolerance And Changes Of Protein Pattern In Italian Ryegrass After Cold Hardening,
2024
Hokuriku National Agricultural Experiment Station, Japan
Assessment Of Freezing Tolerance And Changes Of Protein Pattern In Italian Ryegrass After Cold Hardening, K Tase, M Kobayashi
IGC Proceedings (1977-2023)
The objective of the present study was to assess the freezing tolerance using LT50 (temperature at which 50% mortality occurs) and to get information on changes of protein pattern in Italian ryegrass (Lolium multiflorum Lam.) after cold hardening. The correlation coefficient between LT50 and percentage of survival plants under field conditions was significantly high at 0.701 ". LT50 was considered to be useful to assess different genotypes and change of freezing tolerance during the winter. This technique will be used in breeding programmes to improve the freezing tolerance. Soluble proteins extracted from hardened and non-hardened seedlings were analysed by …
Breeding And Selecting Of New Improved Cultivars Of Trifolium Subterraneum Spp. Brachucalucinum,
2024
South Australian Department of Agriculture
Breeding And Selecting Of New Improved Cultivars Of Trifolium Subterraneum Spp. Brachucalucinum, C T. De Koning, I D. Kaehne, P.G H. Nichols, R L. Tuckwell
IGC Proceedings (1977-2023)
A national programme for the improvement of Trifolium subterraneum ssp. brachycalycinum has been instigated by the National Subterranean Clover Improvement Programme (NSCIP), Australia. At present there are only 2 commercial cultivars,·Ctare and Rosedale. The overall aim of the programme is to develop and release well-adapted early- to mid-season cultivars of ssp. brachycalycinum which are persistent in farming systems and resistant to pests and diseases. Bight crosses were made in 1988. The parents used for the crosses were selected for their earliness, general good performance and strong vigour. Preliminary characterisation of breeding lines in 1991 has shown that early flowering, strong …
Intergeneric Hybrids Of Male Sterile Italian Ryegrass Crossed With Tall Fescue,
2024
National Grassland Research Institute
Intergeneric Hybrids Of Male Sterile Italian Ryegrass Crossed With Tall Fescue, K Suginobu, T Takamizo, T Komatsu, F Akiyama, Y Tominaga
IGC Proceedings (1977-2023)
Seed fertility and yield of male sterile Italian ryegrass (Lolium multiflorum Lam.) crossed with tall fescue (Festuca arundinacea Schreb,) varied from 2.8 to 100% and from 0.04 to 9.45 g, respectively. Significant positive correlations were found between seed fertility and seed yield per plant and between seed fertility and Pl percentage of the harvested seed, Spike type and plant type were very similar to those of tall fescue. By contrast, more than SO% of Pl plants tillered In the second crop were unlike tall fescue; however, persistency of the Pl was similar to that of tall fescue. In …
Evaluating Germplasm Collections Of Subterranean Clover For Plant Characteristics Influencing Seed Yield,
2024
lnstituto Sperimentale per le Colture Foraggere
Evaluating Germplasm Collections Of Subterranean Clover For Plant Characteristics Influencing Seed Yield, E Piano, L Pecetti, M Romani, F Spanu
IGC Proceedings (1977-2023)
Strains of Trifalium brachycalycinumm (B) and Trifolium subterraneum • (S) were evaluated for burr burial ability and capacity to set seed when ' burial was artificially prevented. In one experiment S buried a higher • number of burrs and more deeply in the soil relative to B. There was evidel)ce that unburied burrs were undeveloped in S while a higl\ proportion of them developed in. B. In a second experiment prevention of burial drastically reduced seed yield in both species but the reduction was higher in S. Effects on yield components were. also differen.1 in the 2 species, Seeds/burr declined …
