bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of freshly cultured lactic acid bacteria as silage inoculants
Authors: MERRY R. J. , DHANOA M. S. , THEODOROU M. K. 
Published: April 2006

AbstractThe use of freshly cultured lactic acid bacteria in comparison with conventional freeze‐dried preparations as inoculants for grass silage was examined. Perennial ryegrass was ensiled in laboratory silos, either untreated or treated with formic acid, or a commercial freeze‐dried strain of Lactobacillus plantarum, or a fresh culture of the same strain of L. plantarum, or fresh cultures of Pediococcus pentosaceous, or Lactococcus lactis alone or in combination with L. plantarum. All inoculants were applied at a rate of 106 colony‐forming units g−1 fresh matter, with the mixtures containing a 1:l ratio of each species. Herbage treated with freshly cultured inoculants exhibited shorter lag times, in relation to the initiation of pH decline, than those associated with untreated or freeze‐dried inoculant‐treated herbages. Treatment of herbage with inoculants containing L. plantarum increased the initial speed of pH decline. In comparison with silages made with freeze‐dried L. plantarum, in measurements made during the initial 14 d of ensilage, those inoculated with fresh cultures bad significantly (P<0·05) higher lactic acid concentrations and significantly (P·0.05) lower pH values. Both P. pentosaceous and L. lactis initiated a rapid fermentation, but compared to L. plantarum alone, or mixtures of L. plantarum with P. pentosaceous or L. lactis, these cultures demonstrated intermediate rates of lactic acid production and pH decline. All mature (105 d) silages were of good quality with pH values of four or less, low ammonia‐N concentrations (<100gkg−1 total N) and no detectable levels of clostridia or butyric acid. Results suggested that the main advantage of freshly cultured inoculants over their freeze‐dried counterparts may lie in their metabolic state when added to herbage.
The selection of winter wheat varieties for whole‐crop cereal conservation
Authors: WELLER R. F. , COOPER A. , DHANOA M. S. 
Published: April 2006

AbstractTen commercial varieties of winter wheat were sampled at different stages of growth, and dry mailer (DM) yields and potential nutritional quality, as determined by modified acid detergent fibre concentration (MADF), were measured. Maximum yields for the different varieties were spread over a four‐week period, when the DM content was above 350 g kg−1. When the varieties were harvested for conservation as either fermented (DM 380 g kg−1) or alkaline (DM 580 g kg−1) whole crop, the mean MADF concentration was similar at both harvests, with large differences recorded between varieties. At both harvests the quality of the crops was sharply increased by raising the cutting height from 10 to 40 cm above ground level.
Persistence of Ladino white clover ecotypes and its relationship with other agronomic traits
Authors: PIANO E. , ANNICCHIARICO P. 
Published: April 2006

AbstractSixteen landraces and twelve natural populations of Ladino white clover, and six large‐leaved control varieties, were assessed in Lodi (southern Lombardy, Italy) under a mowing regime for persistence, defined as ratio between clover dry matter (DM) yield over the last two years and clover DM yield over the five‐year crop cycle. Clover content in the sward was on average 35·2% in the fourth year and only 5·5% in the fifth year. Natural populations showed greater persistence and larger variation for this feature than landraces. Six natural populations were more persistent and higher yielding in the long‐term than the Italian variety Espanso and one of these populations performed better than the best of the control varieties, namely Lune de Mai and Olwen, at P < 005. Persistence of the ecotypes was positively associated with stolon density and DM yield assessed in the third year, and to intemode length, whilst it was inversely related to seed yield and its components, especially the production of seed heads, so that hardly any ecotype could combine good persistence with high seed yield. This study discusses the potential use of these genetic resources in white clover breeding and suggests stolon density as a low‐cost, approximate indicator of long‐term yield.
Sites of photoperception in white clover
Authors: THOMPSON L. 
Published: April 2006

AbstractWhite clover (Trifolium repens) grows both horizontally, via the stolon, and vertically, via the petiole, through its environment. Comparing the effects of clear and opaque paint allowed the localization of two photoperceptive sites. Stolon growth (horizontal) was altered by the radiation environmental the node, and petiole growth (vertical) by radiation perceived at the petiole tip. Photoperception these two sites provides a mechanism by which the plant can direct its growth to exploit its environment maximally.
The influence of cutting date and previous fertilizer treatment on the productivity and botanical composition of species‐rich hay meadows on the Somerset Levels
Authors: KIRKHAM F. W. , TALLOWIN J. R. B. 
Published: April 2006

AbstractThe effects on productivity, botanical and chemical composition of cutting species‐rich hay meadows in Somerset on four different dates between late May and early September in two consecutive years, were measured. Plots that had received 200 kg N ha−1 year−1 with low levels of P and K for the previous 5 years were compared with plots that had previously received no fertilizer.Previous fertilizer treatment increased metabolizable energy (ME) production only with cutting in May. Dry‐matter (DM) yield increased significantly with date of cutting until August, whereas ME value declined correspondingly. There was no difference in either yield or quality of herbage cut between August and September. ME output per hectare increased very significantly between May and July, but showed no further change between cutting dates.Botanical diversity was reduced by cutting in May after 1 year and by cutting in either May or September after 2 years, and was greatest with cutting in August. The dominance of Holcus lanatus on previously fertilized plots increased after cutting in either May or September. The contribution to vegetation cover of species that regenerate primarily by seed, including annuals, was greatly influenced by cutting date in preceding years, whereas species that regenerate vegetatively were not affected.
Analysis of adaptation of grass/legume mixtures to Italian alpine and subalpine zones through an additive main effects and multiplicative interaction model
Authors: ANNICCHIARICO P. , BOZZO F. , PARENTE G. , GUSMEROLI F. , MAIR V. , MARGUERETTAZ O. , ORLANDI D. 
Published: April 2006

AbstractFourteen grass/legume mixtures, mostly including white clover or lucerne, in association with a variable number of other forage species were grown at six Italian alpine and subalpine locations under a mowing regime. The response of the mixtures in terms of dry‐matter (DM) yield and visually estimated legume percentage over the second and third years of crop cycle was investigated through an additive main effects and multiplicative interaction (AMMI) analytical model. Locations and mixture‐location interaction effects were significant whereas mixture was not. The interaction effect was very large, and the first two interaction principal component (PC) axes were significant at P<0·001. PC 1 accounted for 88% and 92% of the interaction variation for DM yield and legume percentage respectively. Both for sites and for mixtures, the ordination on PC 1 for these variables was very similar, indicating that the interaction effects for DM yield tended to parallel those for legume percentage. The adaptive response of the mixtures mainly depended on the response of their legume components. White clover was specifically adapted to locations with high soil clay content, probably through better tolerance to the associated severe waterlogging. Lucerne performed relatively better at high‐yielding, favourable sites, probably because of its greater competitive ability than associated grasses under conditions that emphasize competitive effects. Minor interaction effects were related to the response of cocksfoot and timothy, the latter being indispensable for high DM yield of mixtures at high‐elevation, cool‐summer sites. No clear advantage of having a high number of components in the mixture was apparent, and it was concluded that the association of timothy and cocksfoot with one legume should be adequate for most situations in the given region.
Herbage production from swards containing a range of grass, forb and clover species and under extensive management
Authors: FISHER G. E. J. , BAKER L. J. , TILEY G. E. D. 
Published: April 2006

AbstractThree small plot experiments were conducted to investigate the effects of species of grass and forbs, defoliation regime, inclusion of white clover and forb blend on the herbage dry matter (DM) yield, botanical composition and mineral content of swards managed with zero fertilizer inputs. The results of all three experiments were characterized by decline in herbage production and large variations in treatment effects over the harvest period.When sown singly with a standard grass mix the species that competed well with grasses and produced annual forb herbage yields greater than 20 t DM ha−1 were black knapweed, oxeye daisy, ribwort plantain, burnet, birdsfoot trefoil, chicory, kidney vetch, red clover and white clover. When sown singly with a standard forb mix, grass species significantly affected the annual yield of total (P<005). grass (P<001) and forb (P<0.001) herbage. The species that most surpressed the yield of forbs were common bent, Yorkshire fog and perennial ryegrass. Those that allowed for the highest yield of forbs were rough meadow grass, sweet vernal grass and crested dogstail. Averaged over the three harvest years, defoliation regime did not significantly affect herbage production, but the inclusion of white clover in mixtures increased the yield of grasses (P<0.01) The use of rosette‐type forb blends increased forb yield (P<0.01), compared with erect‐type blends.The effects of treatments on herbage N and mineral contents and yields were inconsistent. However, there was some evidence to support the view that the presence of forb species in swards can result in greater contents of minerals in herbage, compared with grass‐only swards.
Effects of sward type and rest periods from sheep grazing on white clover presence in perennial ryegrass/white clover associations
Authors: GOODING R. F. , FRAME J. , THOMAS C. 
Published: April 2006

AbstractThe effects of the imposition and timing of a rest period from continuous sheep stocking, for a conservation cut, on white clover presence in forty perennial ryegrass/white clover associations were studied over two full grazing seasons. Each association consisted of one grass variety along with one white clover variety, the grasses being diploid and tetraploid ryegrasses from each of five maturity groups and the white clovers from each of four leaf size categories. The presence of white clover within each association was assessed at the beginning and end of both seasons by means of a 0–64‐m2 quadrat subdivided into 100 squares, each 80 mm × 80 mm, the number of squares in which any part of a white clover plant was visible being recorded. Complementary point quadrat data were also collected.Although continuous sheep stocking did not necessarily have an adverse effect on white clover presence, a July to mid‐August rest period increased white clover proportions in the swards (means: unrested, 48–1; April to late May rest, 32.7; July to mid‐August rest, 67.3 ‐ s.e.d. 7.59; P < 0.05) the benefit increasing with increasing white clover leaf size. The early rest period (April to late May) reduced white clover presence and the late rest period (July to mid‐August) increased white clover presence, these effects being intensified with increasing white clover leaf size (very large‐leaved clover: unrested, 20.6; April to late May rest, 8.3;July to mid‐August rest, 41.1 and small‐leaved clover: unrested, 96.3; April to late May rest, 84.8; July to mid‐August rest, 97 ‐ s.e.d. 9.2; P <0001). Tetraploid ryegrass/white clover associations had consistently and significantly more white clover than diploid ryegrass/white clover associations of similar ryegrass maturity group (tetraploid, 53.4; diploid 44.8 ‐ s.e.d. 2.12; P <0.001) and associations with early maturing ryegrass contained more white clover than those with late maturing ryegrasses, the effect of maturity group being greater than that of ploidy. Overall, white clover presence increased with increasing openness of grass growth habit.
The response of mini‐swards of perennial ryegrass/white clover to simulated rainfall following slurry application
Authors: WIGHTMAN P. S. , FRANKLIN M. F. , YOUNIE D. 
Published: April 2006

AbstractPerennial ryegrass/white clover mini‐swards were used lo determine whether sward responses to slurry were modified by subsequent simulated rainfall (SR). Combinations of two SR volume rates (6.5 and 13 mm), three SR timings (3, 24 and 48 h after slurry application) and two slurry types (cattle, pig) were compared with a fertilizer control (no SR). Scorch, smother and growth of marked stolons and tillers were monitored after slurry application, and yields of both species were recorded. Slurry coverage of plastic squares indicated that smother may be greater on horizontally orientated leaves (clover). Reduced grass leaf growth and numbers of clover growing points in the week following slurry application were attributed mainly to smother, and possibly other phytotoxic effects of slurry. Reasons for the superior clover growth with cattle slurry arc unknown, although its higher P and K content may have contributed. Timing of rainfall is important in influencing sward responses to slurry application. Results suggest that application of slurry may be most beneficial when it immediately precedes rainfall and that longer intervals between slurry application and rainfall reduce grass and clover growth through either greater ammonia loss or slurry negative effects.
The effect of plane of winter nutrition and sward height on the performance of steers grazing grass/white clover swards
Authors: YARROW N. H. , PENNING P. D. , JOHNSON R. H. 
Published: April 2006

AbstractAn experiment was carried out over 2 years to examine the interactions between two planes of winter nutrition and summer gracing at 5.5 and 7.5 cm compressed sward height on the performance of Limousin X Friesian steers grazing grass/white clover swards. Diets were offered in winter to give liveweight gains of either 0.5 (low) or 0.8 (high) kg d−1. The experiment was repealed over 2 years. Liveweights gains (low 0.50 vs. high 0.84 kg d−1 s.e.d. ±0.044) were achieved in winter 1 and (low 0.55 vs. high 0.91 kg d−1, s.e.d. ±0.041) in winter 2. These differences resulted in animals from the high treatment being 44 and 60 kg head−1 heavier at turn‐out than the low‐treatment animals in years I and 2, respectively. There was evidence of compensatory growth with animals from the low treatment subsequently tending to grow faster than those from the high treatment, with liveweight gains during the period from turn‐out to 84 d of 1.27 vs. 1.18 s.e.d. ±0.65 kg d−1; P= 0–213 and 1.11 vs. 0.95 s.e.d. ±0.062 kg d−1; P=0.015 in summers I and 2 respectively. In general, animals grazing the short sward tended to grow more slowly than those on the tail swards (1.18 vs. 1.27 s.e.d. ±0.065 kg d−1; P= 0.166 and 0.93 vs. 113 s.e.d. ±0.062 kg d−1, P = 0.002) for years 1 and 2 respectively. Growth rates in year 1 were significantly higher than those in year 2. However, increased summer growth rates did not compensate for the differences in live weight established during the winter, and more animals reached slaughter weight in a shorter time from the high than the low treatment. Mean stocking rate on treatments 5.5 and 7.5 over the 2 years were 5.2 and 4.3 animals ha−1: differences were significant in year 2 (P <0.01). The 5.5 cm sward treatment also gave a greater liveweight gain ha−1 than the 7.5‐cm sward treatment in both years with a mean for the two years of 670 vs. 572 kg ha−1 but differences were not significant.
Effects of different levels of fertilizer application to veld on growth of steers and chemical composition of the herbage
Authors: Cilliers J. W. , Van Biljon P. L. , Tolmay E. , Coertze C. 
Published: April 2006

The effects of different levels of N fertilization (no N, 40 kg N and 80 kg N ha−1 year−1), P fertilization (no P, 21 kg P ha−1 year−1 and 21 kg P plus 53 kg K ha−1 year−1) and stocking rates (0·52 large stock units (LSU) ha−1, 0·78 LSU ha−1 and 1·56 LSU ha−1) on the chemical composition and in vitro dry matter digestibility of the herbage and the liveweight gains of steers were determined in the western variant of the Bankenveld in South Africa.The average daily liveweight gains (ADLGs) of the steers increased with increasing level of N fertilization. Fertilization with P had a positive effect on ADLG only when 53 kg of K was applied with 21 kg of P ha−1. Higher stocking rates reduced ADLGs. The liveweight gains ha−1 increased as the rates of N and P fertilization increased. The medium stocking rate (0·78 LSU ha−1) gave a higher liveweight gain ha−1 than the lowest stocking rate (0·52 LSU ha−1), but the highest stocking rate (1·56 LSU ha−1) reduced liveweight gain ha−1.In general, in terms of chemical components, a higher nutritive value of the veld herbage resulted from N fertilization. The higher crude protein (CP) content of the herbage, resulting from higher stocking rates, should be seen against the background of lower liveweight gains ha−1 at the highest stocking rate.On pasture with similar contents of CP and acid detergent fibre (ADF), higher ADLG of steers was found as a result of P and K fertilization, especially for herbage with a lower CP and a higher ADF content, implying better utilization of the nutrients in such herbage with P and K fertilization, although P was also supplemented through a lick.
Effects of an autumn defoliation on overwintering, spring growth and yield of a white clover/grass sward
Authors: FRANKOW‐LINDBERG B. E. , SVANÄNG K. , HÖGLIND M. 
Published: April 2006

AbstractAn established sward of binary mixtures of meadow fescue (Festuca pratensis) and white clover (Trifolium repens) (either AberHerald, Grasslands Huia or Sandra) was subjected to (A) no further defoliation, (B) a defoliation in late September or (C) a defoliation in late October after four harvests had been taken during the grazing season. About a tonne of dry matter (DM) was removed by the autumn defoliations. There were two levels of nitrogen application in spring, either 0 or 90 kg ha−1. The development of grass and clover morphology and population sizes from early autumn until the first harvest the following year was followed by regular sampling of the above‐ground material. Stolons were analysed for total non‐structural carbohydrates (TNCs), and the temperature at stolon level was continuously recorded. There were no interactions between autumn defoliation, clover cultivar or nitrogen treatments on any of the parameters studied. White clover growing‐point numbers and stolon morphological characteristics were reduced in size during the winter and did not recover during the spring. A defoliation in late September resulted in the greatest reduction, whereas there were no differences between the other two treatments. The grass tiller population increased from early autumn until the last sampling occasion in May, but both autumn defoliations resulted in a smaller increase. Defoliation in late September had the greatest impact. The TNC content of white clover stolons fell from about 350 g kg−1 to 150 g kg−1 DM from late autumn until late April. There were small differences between the treatments, but a defoliation in late September resulted in a significantly lower level in late autumn. The temperature amplitude at stolon level was consistently greater in plots defoliated in late September. Total DM harvested in spring was 4367, 2564 and 3536 kg ha−1, of which 388, 352 and 460 kg ha−1 was white clover, from treatments A, B and C respectively. It is concluded that an autumn defoliation may affect the overwintering of white clover negatively, but that the effect on the grass may be even more detrimental.
Prediction of the shoot production of heather under grazing in the uplands of Great Britain
Authors: PALMER S. C. F. 
Published: April 2006

AbstractAn empirical model for the annual shoot production of heather Calluna vulgaris in the absence of grazing in the uplands of Great Britain is presented. Production is modelled as a function of the growth phase of the heather and weather conditions during the summer growing season and the previous winter.The effects of grazing, principally by sheep, on changes in heather cover after burning are reviewed. A simple model of annual cover change is proposed, and fitted to data from dry and wet heaths in Scotland.A model of the influence of grazing on annual heather shoot production is developed for dry heath.The models indicate that previously published estimates of the utilization levels that heather can tolerate without a reduction in shoot production may be too high. For pioneer and early building heather, estimated threshold utilization levels are 16% in summer and 24% in autumn. Furthermore, it is suggested that any level of utilization will reduce the rate of increase of heather ground cover after burning.
Investigating the basis of substrate recognition in the pC221 relaxosome
Authors: Caryl Jamie A. , Thomas Christopher D. 
Published: April 2006

SummaryThe nicking of the origin of transfer (oriT) is an essential initial step in the conjugative mobilization of plasmid DNA. In the case of staphylococcal plasmid pC221, nicking by the plasmid‐specific MobA relaxase is facilitated by the DNA‐binding accessory protein MobC; however, the role of MobC in this process is currently unknown. In this study, the site of MobC binding was determined by DNase I footprinting. MobC interacts with oriT DNA at two directly repeated 9 bp sequences, mcb1 and mcb2, upstream of the oriT nic site, and additionally at a third, degenerate repeat within the mobC gene, mcb3. The binding activity of the conserved sequences was confirmed indirectly by competitive electrophoretic mobility shift assays and directly by Surface Plasmon Resonance studies. Mutation at mcb2 abolished detectable nicking activity, suggesting that binding of this site by MobC is a prerequisite for nicking by MobA. Sequential site‐directed mutagenesis of each binding site in pC221 has demonstrated that all three are required for mobilization. The MobA relaxase, while unable to bind to oriT DNA alone, was found to associate with a MobC–oriT complex and alter the MobC binding profile in a region between mcb2 and the nic site. Mutagenesis of oriT in this region defines a 7 bp sequence, sra, which was essential for nicking by MobA. Exchange of four divergent bases between the sra of pC221 and the related plasmid pC223 was sufficient to swap their substrate identity in a MobA‐specific nicking assay. Based on these observations we propose a model of layered specificity in the assembly of pC221‐family relaxosomes, whereby a common MobC:mcb complex presents the oriT substrate, which is then nicked only by the cognate MobA.