EFFECTIVENESS OF ONE CYCLE OF PHENOTYPIC SELECTION FOR IN VITRO DIGESTIBILITY IN BROMEGRASS AND ORCHARD GRASS

1977 ◽  
Vol 57 (1) ◽  
pp. 57-60 ◽  
Author(s):  
B. R. CHRISTIE
Keyword(s):  
Dactylis Glomerata ◽  
Phenotypic Selection ◽  
Bromus Inermis ◽  
The Other ◽  
In Vitro Digestibility ◽  
Orchard Grass ◽  
Selection For ◽  
Dactylis Glomerata L

Twenty-seven topcross and nine polycross progenies of bromegrass (Bromus inermis Leyss) were evaluated for in vitro digestibility (IVD) and yield. Two groups of polycross progenies of orchard grass (Dactylis glomerata L.) were also evaluated. Bromegrass plants varied in IVD from 58 to 70%, while their topcross progenies varied from 58.2 to 64.6%. The correlation between parents and progeny was 0.55. Selection for high IVD did not result in any improvement over cv. Saratoga. One group of 10 orchard grass plants was high in IVD (62–66%), while the other was low (50–58%). The polycross progenies of these two groups were similar (68.2% vs. 68.5%). Selection for IVD was not effective in altering progeny IVD values.

VARIABILITY OF IN VITRO DIGESTIBILITY AMONG CLONES OF BROMEGRASS AND ORCHARDGRASS

1968 ◽  
Vol 48 (1) ◽  
pp. 67-73 ◽  
Author(s):  
B. R. Christie ◽  
D. N. Mowat
Keyword(s):  
Dactylis Glomerata ◽  
Bromus Inermis ◽  
In Vitro Digestibility ◽  
Phenotypic Characteristics ◽  
Whole Plant ◽  
Stems And Leaves ◽  
Dactylis Glomerata L ◽  
Whole Plants ◽  
Genotypic Effects

Individual clones of bromegrass (Bromus inermis Leyss) and orchardgrass (Dactylis glomerata L.) were harvested at corresponding stages of maturity within each species. The orchardgrass clones were harvested in 1962, and the in vitro digestibility (IVD) was based on the whole plant. Bromegrass clones, harvested in 1965 and 1966, were separated into leaves and stems. The IVD of each component was determined, and from these, the IVD for the whole plant was estimated.Among 444 orchardgrass clones, IVD values ranged from 49 to 68%. Most of the variation was attributed to genotypic effects. For approximately 250 clones of bromegrass, IVD values ranged from 66 to 75%, 58 to 73%, and 62 to 74%, for leaves, stems, and whole plants respectively. Over the 2-year period, differences among stems and whole plants were significant. Correlations between leaf and stem digestibilities were significant but of low magnitude. Ten clones of bromegrass had stems and leaves of equal digestibility.In bromegrass, IVD values showed no relationship to several phenotypic characteristics.

The in vitro digestibility of parents and hybrids of cocksfoot (Dactylis glomerata L.)

1968 ◽  
Vol 19 (3) ◽  
pp. 373 ◽  
Author(s):  
R Knight ◽  
NG Yates
Keyword(s):  
Combining Ability ◽  
Dactylis Glomerata ◽  
General Combining Ability ◽  
In Vitro Digestibility ◽  
Growth Rhythm ◽  
In Vitro Technique ◽  
Selection For ◽  
Dactylis Glomerata L

The digestibility of a range of genotypes of cocksfoot (Dactylis glomerata L.) and their hybrids was estimated by an in vitro technique at eight harvests over a period of 14 months. The material for analysis was grown in a Mediterranean type environment with summer irrigation and obtained by recurrent defoliation of sward plots. Digestibility values tended to be lower in summer than in winter, although some material showed a fall in digestibility in the middle of winter. Within a harvest there were correlations between general combining ability and parental performance, but there was little uniformity in ranking of parents or their progenies from one harvest to the next, which would make selection for uniform high digestibility very difficult. Reasons for the fluctuations are not known, and were not obviously correlated with any aspect of the growth rhythm apart from a correlation with heading on one harvest occasion.

RESPONSE OF ORCHARD GRASS TO MULTIPLE HARVESTS AND RATES OF NITROGEN IN POST-SEEDING YEARS

1977 ◽  
Vol 57 (3) ◽  
pp. 763-770
Author(s):  
H. T. KUNELIUS ◽  
MICHIO SUZUKI
Keyword(s):  
Dry Matter ◽  
Dactylis Glomerata ◽  
Late Summer ◽  
Total N ◽  
Orchard Grass ◽  
Nitrate N ◽  
Dactylis Glomerata L ◽  
N Rates

Frode orchard grass (Dactylis glomerata L.) was fertilized with 99–495 kg N/ha/yr in three equal applications and harvested three or four times per season over a 3-yr period to determine the productivity, quality of forage and persistence of stands. The application of N resulted in significant (P =.001) linear and quadratic increases in dry matter (DM) yields. Higher DM yields were obtained with the 3-harvest system while the yield distribution within the season was more uniform for the 4-harvest system. Total N concentrations of orchard grass increased linearly with the N rates. Total N yields were dependent on the rates of applied N with the recovery of applied N ranging from 39 to 70% at 99–297 kg N/ha/yr, respectively. The in vitro disappearance of DM was slightly reduced by the high N rates in the 1st and 2nd harvests. The nitrate-N concentrations were highest in the early and late summer ranging from.11 to.29% at 297–495 kg N/ha/yr, respectively. The persistence of orchard grass was better under the 4- than the 3- harvest system.

PERFORMANCE OF HYBRIDS IN ORCHARD GRASS

1973 ◽  
Vol 53 (4) ◽  
pp. 783-789 ◽  
Author(s):  
B. R. CHRISTIE
Keyword(s):  
Forage Yield ◽  
In Vitro Digestibility ◽  
Average Yield ◽  
Male Sterile ◽  
Orchard Grass ◽  
Hybrid Superiority ◽  
Single Cross ◽  
Dactylis Glomerata L ◽  
Single Cross Hybrids

Single-cross hybrids of orchard grass (Dactylis glomerata L.) were evaluated for yield, in vitro digestibility (IVD), and relative maturity in three trials. All trials were planted broadcast, using seed produced on male-sterile clones. All trials were harvested for 2 yr. The average yield of the 48 hybrids tested was 98% of that for the cultivar Frode in the first cut each year, and 103% over the season. The most productive hybrid produced 28% more forage than Frode in the first cut, and 15% more over the season. For IVD, there was no evidence of hybrid superiority. The results indicate that the use of hybrids can result in an increase in forage yield.

SEEDING YEAR YIELDS AND QUALITY OF ORCHARD GRASS AS INFLUENCED BY N RATES AND HARVEST SYSTEMS

1977 ◽  
Vol 57 (2) ◽  
pp. 427-431
Author(s):  
H. T. KUNELIUS ◽  
MICHIO SUZUKI
Keyword(s):  
Dry Matter ◽  
Dactylis Glomerata ◽  
Total N ◽  
Orchard Grass ◽  
Application Systems ◽  
Nitrate N ◽  
Dactylis Glomerata L ◽  
N Rates

Frode orchard grass (Dactylis glomerata L.) was seeded at 20 kg/ha without a companion crop in 1971 and 1972. Nitrogen was applied at 37–185 kg/ha at seeding and after the first harvest, and the stands were subjected to three harvest systems. Total dry matter (DM) yields increased up to 74 kg N/ha/application. Systems with the latest first harvest and longest regrowth intervals produced highest DM yields. Early seeding was important for the production of high DM yields. Late fall harvest in October resulted in poor winter survival. The total N concentrations of orchard grass ranged from 2.58 to 4.40%, with small or no increases beyond 111 kg N/ha/application. In vitro disappearance of DM was not affected by N rates but varied from 60.7 to 69.8% with the highest readings for the early or short regrowth interval harvests. Nitrate-N concentrations of orchard grass were < 0.15% at 37 kg N/ha/application. At or above 74 kg N/ha/application, nitrate-N usually exceeded 0.15% level which might be potentially toxic to livestock consuming the forage.

scholarly journals Recurrent restricted phenotypic selection for forage yield in timothy and orchardgrass

1995 ◽  
Vol 75 (4) ◽  
pp. 871-875 ◽  
Author(s):  
D. Shateryan ◽  
B. E. Coulman ◽  
D. E. Mather
Keyword(s):  
Recurrent Selection ◽  
Dactylis Glomerata ◽  
Phenotypic Selection ◽  
Phleum Pratense ◽  
Forage Yield ◽  
Correlated Responses ◽  
Plant Persistence ◽  
Selection For ◽  
Dactylis Glomerata L ◽  
Phleum Pratense L

Three cycles of recurrent restricted phenotypic selection for forage yield were carried out in orchardgrass (Dactylis glomerata L. 'Avon' and 'Pennlate') and timothy (Phleum pratense L. 'Salvo' and 'Drummond'). The objectives of this study were to measure the effectiveness of this selection and to assess whether the selection produced any correlated responses on other characters. The three selected cycles and the original populations (cycle 0) were evaluated in both sward and space-planted experiments over a period of 4 yr. For the majority of the years of evaluation, there were no significant (P < 0.05) differences in forage yield among the different selection cycles. Under space-planted evaluation, cycle 3 of Drummond timothy was lower in both forage and seed yield than the other populations. In general, there was a trend to taller plants with greater circumferences in orchardgrass, and shorter, smaller plants in timothy over selection cycles. Selection had little effect on plant persistence and maturity. In conclusion, three cycles of recurrent restricted phenotypic selection were not effective in improving the forage yield of timothy or orchardgrass. Key words: Timothy, Phleum pratense, orchardgrass, Dactylis glomerata, recurrent selection

Performance of tetraploid progeny derived from 2x–4x intersubspecific crosses in Dactylis glomerata L.

Genome ◽  
1988 ◽  
Vol 30 (4) ◽  
pp. 591-596 ◽  
Author(s):  
M. D. Casler ◽  
P. M. Hugessen
Keyword(s):  
Dactylis Glomerata ◽  
Forage Yield ◽  
Neutral Detergent Fiber ◽  
Heritable Variation ◽  
Dry Matter Digestibility ◽  
Orchard Grass ◽  
Dactylis Glomerata L ◽  
Tetraploid Progeny ◽  
Tetraploid Parent

The Dactylis glomerata L. species complex is a genetically diverse group of naturally occurring diploid (2n = 2x = 14), tetraploid (2n = 4x = 28), and hexaploid (2n = 6x = 42) subspecies. The diploid subspecies tend to be geographically isolated and genetically distinct. Each subspecies probably possesses alleles for adaptation to specific environmental regimes. The objective of this research was to evaluate tetraploid progeny from 2x–4x intersubspecific crosses for forage yield and quality relative to their tetraploid parent. Progeny were developed by two stages of hybridization; intra- and inter-subspecific hybrids were generated from 2x–2x crosses, after which selected diploid progeny were mated, as females, to adapted tetraploid genotypes. From 14 2x–4x crosses, utilizing diploids known to produce 2n eggs, 59 tetraploid progeny were identified. These tetraploid progeny and their parents were vegetatively cloned and established in pots in two greenhouses. Forage was harvested from two replicates of each plant in each greenhouse for a total of six cuttings. Vigor, in vitro dry matter digestibility (IVDMD), and neutral detergent fiber (NDF) were determined. Parent–progeny regressions indicated evidence of heritable variation for vigor and IVDMD, but not for NDF. Favorable heterosis (relative to the tetraploid parent) on a family mean basis was significant only for IVDMD in one family. When selection among progeny within families was possible (in six families), favorable transgressive segregants were observed for all traits in at least one family and in a total of five families. The favorable performance of some tetraploid progeny, combined with the diverse nature of the species, indicate that improvements to cultivated orchard grass are possible. Selection at both the diploid and tetraploid levels will be necessary to achieve these goals.Key words: Dactylis glomerata L., gametic nonreduction, heterosis, heterozygosity, orchard grass, polysomic polyploids.

NITROGENASE ACTIVITY OF ALFALFA GROWN ALONE AND IN MIXTURE WITH GRASS UNDER GREENHOUSE CONDITIONS

1985 ◽  
Vol 65 (3) ◽  
pp. 787-791
Author(s):  
H. A. BURITY ◽  
B. E. COULMAN ◽  
M. A. FARIS
Keyword(s):  
Medicago Sativa ◽  
Nitrogenase Activity ◽  
Dactylis Glomerata ◽  
Phleum Pratense ◽  
Bromus Inermis ◽  
Smooth Bromegrass ◽  
Medicago Sativa L ◽  
Dactylis Glomerata L ◽  
Phleum Pratense L ◽  
Nodule Tissue

A greenhouse experiment has shown that total nitrogenase activity of alfalfa (Medicago sativa L.) is not significantly affected when grown in association with timothy (Phleum pratense L.), smooth bromegrass (Bromus inermis Leyss) or orchardgrass (Dactylis glomerata L.) except after initial harvest when decreased alfalfa activity was associated with smooth bromegrass or orchardgrass. It was concluded that mixed cultures of alfalfa with timothy, smooth bromegrass or orchardgrass have no effect on alfalfa N2 fixation. The results also suggest the occurrence of N transference from alfalfa to associated grasses. It is speculated that this transfer is not primarily due to the death of roots and nodule tissue (after harvest), but involves some degree of N excretion during the period before initial harvest.Key words: Alfalfa-grass mixtures, N2-fixation, nodule activity, N-transference

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