Colonization and performance of a pyrene-degrading bacterium Mycolicibacterium sp. Pyr9 on root surfaces of white clover

Some root-associated bacteria could degrade polycyclic aromatic hydrocarbons (PAHs) in contaminated soil; however, their dynamic distribution and performance on root surface and in inner plant tissues are still unclear. In this study, greenhouse container experiments were conducted by inoculating the phenanthrene-degrading bacterium Diaphorobacter sp. Phe15, which was isolated from root surfaces of healthy plants contaminated with PAHs, with the white clover (Trifolium repens L.) via root irrigation or seed soaking. The dynamic colonization, distribution, and performance of Phe15 in white clover were investigated. Strain Phe15 could efficiently degrade phenanthrene in shaking flasks and produce IAA and siderophore. After cultivation for 30, 40, and 50 days, it could colonize the root surface of white clover by forming aggregates and enter its inner tissues via root irrigation or seed soaking. The number of strain Phe15 colonized on the white clover root surfaces was the highest, reaching 6.03 Log CFU⋅g–1 FW, followed by that in the roots and the least in the shoots. Colonization of Phe15 significantly reduced the contents of phenanthrene in white clover; the contents of phenanthrene in Phe15-inoculated plants roots and shoots were reduced by 29.92–43.16 and 41.36–51.29%, respectively, compared with the Phe15-free treatment. The Phe15 colonization also significantly enhanced the phenanthrene removal from rhizosphere soil. The colonization and performance of strain Phe15 in white clove inoculated via root inoculation were better than seed soaking. This study provides the technical support and the resource of strains for reducing the plant PAH pollution in PAH-contaminated areas.

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Grazing management influences on seasonality and performance of ryegrass and red clover in a mixture

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1985.46.1709 ◽

1985 ◽

pp. 71-76 ◽

Cited By ~ 1

Author(s):

G.P. Cosgrove ◽

R.W. Brougham

Keyword(s):

Species Composition ◽

White Clover ◽

Plant Density ◽

Red Clover ◽

Grazing Management ◽

Total Production ◽

And Performance ◽

Clover Pasture ◽

Summer Grazing ◽

Clover Plant

Grazing management influences on the production and species composition of a ryegrass, red and white clover pasture were evaluated over 3 years. Pastures were grazed by cattle frequently in either winter or summer and infrequently for the remainder of the year or grazed infrequently all year. Frequency was determined by the height of herbage pre-grazing and was lo-12 cm for frequent grazing and 15-20 cm for infrequent grazing. Annual herbage production of 15.1 t DM/ha was not influenced by grazing management but seasonal production was. Management caused both instantaneous and longer term effects on production of component species. Lower summer production because of frequent grazing in that season resulted from a reduction in red clover production from 2.75 to 1.3 t DM/ha. However, ryegrass production in spring was increased by 60% and in summer it was more than doubled by this grazing treatment. Frequent grazing in winter also increased ryegrass and reduced red clover production in summer compared with infrequent grazing all year but had no effect on ryegrass production in spring. Red clover plant density was unaffected by the different grazing managements imposed for two and a half years but subsequently was lower under frequent summer grazing. Red clover dominance in summer and its effect on ryegrass production in spring can be controlled by more frequent grazing in summer and a more even species balance results. Emphasis on spring or summer production can be achieved through grazing management without affecting total production. Keywords: Red clover, ryegrass, grazing frequency, cattle grazing, herbage production, seasonal production

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Isolation, identification, and performance studies of a novel paraffin-degrading bacterium of Gordonia amicalis LH3

Biotechnology and Bioprocess Engineering ◽

10.1007/s12257-007-0168-8 ◽

2008 ◽

Vol 13 (1) ◽

pp. 61-68 ◽

Cited By ~ 29

Author(s):

Dong-Hui Hao ◽

Jian-Qun Lin ◽

Xin Song ◽

Jian-Qiang Lin ◽

Yu-Jie Su ◽

...

Keyword(s):

Performance Studies ◽

Degrading Bacterium ◽

And Performance

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SOME ASPECTS OF THE DEVELOPMENT AND PERFORMANCE OF 'GRASSLANDS 4700' WHITE CLOVER

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1969.31.1272 ◽

1969 ◽

pp. 127-134

Author(s):

P.C. Barclay

Keyword(s):

White Clover ◽

Regional Adaptation ◽

And Performance ◽

Better Than

A brief outline is given of the breed'ing of the new clover 'Grasslands 4700'. Reports are made on the performance of 4700 as single plants at Kaikohe, Palmerston North: Lincoln and Gore, and -as motin swards with associated grasses at Palmerston North. ln all trials, 4700 was superior to Hum in wmter, and equal to or better than Huia in the summer, except at Lincoln where it was inferior. Based on these results seed was released for widespread trials in order to assess its regional adaptation and its performance in mixed swards under different systems of management.

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Effects of ratio of white clover to grass in silage and concentrate supplementation on intake and performance of ewes in late pregnancy

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s030822960003511x ◽

1987 ◽

Vol 1987 ◽

pp. 76-76

Author(s):

R.J. Orr ◽

T.T. Treacher

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Crude Protein ◽

Late Pregnancy ◽

Crude Protein Content ◽

Fresh Weight ◽

Concentrate Supplementation ◽

Grass Silage ◽

Voluntary Intake ◽

And Performance

Widespread adoption of sheep systems based on mixed swards of white clover and grass may result in conservation cuts with a high proportion of clover, which will affect the intake of the silage or hay. The effect of proportion of clover in silage on voluntary intake was measured by offering mixtures of clover and grass silage with clover proportions of 0, 0.20, 0.40 and 0.60 with (S) and without (U) a ration of 600 g fresh weight per day of a barley, soya and fishmeal concentrate to 78 Finn Dorset ewes. The concentrate was formulated to have a crude protein content (CP) of 160 g per kg DM with 30 g per kg DM derived from fishmeal. The silages were made separately in 1984, with formic acid added at approximately 3.51 per tonne, from uninterrupted spring growths of perennial ryegass (Loliua perenre cv. Melle) cut on 16 June and white clover (Trifolium repens cv. Blanca) cut on 17 July and both were chopped. Mixtures of the two silages were made for each individual ewe separately each day, immediately prior to feeding.

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Effect of sward surface height of mixed swards of ryegrass/white clover on the intake and performance by ewes and their twin lambs

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600034759 ◽

1987 ◽

Vol 1987 ◽

pp. 37-37

Author(s):

R.J. Orr ◽

P.D. Penning ◽

A.J. Parsons ◽

T.T. Treacher

Keyword(s):

Lolium Perenne ◽

Perennial Ryegrass ◽

White Clover ◽

Trifolium Repens ◽

Continuous Variable ◽

Stocking Rate ◽

Animal Performance ◽

And Performance ◽

Grass Sward

Mixed swards of perennial ryegrass (Lolium perenne cv. S23) and white clover (Trifolium repens cv. Huia) were maintained at sward surface heights (SSH) of 3 (GC3), 6 (GC6) and 9 cm (GC9) by continuous variable stocking to examine effects on sward and animal performance. In addition, a pure grass sward of S23 was kept at 6 cm (G6) and fertilized with 14 applications of 30 kg N per ha at fortnightly intervals, beginning on 25 March. The swards were sown in August 1983, cut twice in 1984, in May and June, and then grazed thereafter. Fertilizer was applied to the seedbed at 40 kg N per ha, 20 kg P205 per ha and 20 kg K20 per ha. In March 1984 and 1985, 20 kg per ha each of P205 and K2O were applied to all plots.Dry sheep grazed the paddocks (0.69 ha) to the required SSH's with grazing starting on 4 April, 9 April, 12 April and 24 April for treatments GC3, G6, GC6 and GC9, respectively. On 24 April, two days after lambing, core groups of 8 Scottish Halfbred ewes with twin lambs were put on the plots. Additional ewes, kept on swards similar to the treatment areas, were used to adjust the stocking rate to maintain the SSH's. These were measured three times each week with 200 readings per plot.

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Investigations into suitability of Trifolium occidentale as a host plant for two common pasture pests

New Zealand Plant Protection ◽

10.30843/nzpp.2014.67.5788 ◽

2014 ◽

Vol 67 ◽

pp. 250-255

Author(s):

P.J. Gerard ◽

K.M. O'Donnell

Keyword(s):

Host Plant ◽

White Clover ◽

Trifolium Repens ◽

Stress Factors ◽

Strong Preference ◽

Choice Test ◽

Sitona Lepidus ◽

Clover Root ◽

And Performance ◽

Trifolium Occidentale

Western clover (Trifolium occidentale) is a diploid perennial clover that is reported to be one of the progenitors of white clover (Trifolium repens) The ability to produce hybrids between T repens and T occidentale provides an opportunity to introduce factors to improve white clover tolerance to common stress factors A series of assays was undertaken to compare the feeding and performance of two contrasting pests on two T occidentale lines and two T repens cultivars Clover root weevil (Sitona lepidus) adults showed a preference for T repens but this diminished if weevils had been previously exposed to T occidentale Weevil longevity feeding levels and oviposition were comparable over 32 days indicating T occidentale is a host plant for adult S lepidus Clover flea (Sminthurus viridis) showed a strong preference for T repens over T occidentale in a choice test and higher feeding levels on T repens in the nochoice test

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An evaluation of pure-bred and cross-bred dairy ewes in a commercial sheep milking operation

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600022868 ◽

1992 ◽

Vol 1992 ◽

pp. 176-176

Author(s):

N J Brown ◽

P R English ◽

J A Roden ◽

G Burgess

Keyword(s):

Milk Yield ◽

White Clover ◽

Milk Fat ◽

Alternative Route ◽

Commercial Unit ◽

Machine Milking ◽

Dairy Ewes ◽

Sheep Milk ◽

And Performance ◽

The Uk

Sheep milk and its products are regaining popularity with approximately 15,000 sheep currently being milked in the UK. Extreme dairy type ewes such as the Friesland are expensive compared to commercial genotypes and the crossing of dairy type sires with commercial ewes to produce cross-bred daughters for milking offers an alternative route of entry into milking sheep. An investigation was carried out on a commercial unit in Aberdeenshire milking around 150 ewes to assess the relative suitability and performance of pure-bred and cross-bred dairy ewes under commercial conditions.The study involved first lactation ewes, 5 Friesland x Scotch Halfbreds being compared with 5 pure-bred Frieslands. The ewes lambed at 15 months of age between 20 and 27 May and the ewes were grazed on ryegrass/white clover swards. Ewes nursed their lambs for four weeks after lambing and machine milking started on day 29 of lactation. Milk yield was recorded weekly while milk fat and protein were measured at two weekly intervals.

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Comparison of drought resistance in strawberry clover and white clover

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2007.69.2658 ◽

2007 ◽

pp. 219-222 ◽

Cited By ~ 2

Author(s):

R.W. Hofmann ◽

W. Lin ◽

S.A. Stilwell ◽

R.J. Lucas

Keyword(s):

Drought Resistance ◽

White Clover ◽

Dry Matter ◽

Water Status ◽

Leaf Water Status ◽

Leaf Quality ◽

Nitrogen Levels ◽

Trifolium Repens L ◽

And Performance ◽

Leaf Parameters

This study set out to compare plant function and performance of strawberry clover to that of white clover. To test this, the two species were exposed to drought for 4 weeks under controlled environmental conditions. Water stress reduced the size and dry matter of white clover leaves by more than 50%, whereas strawberry clover leaves remained unaffected. White clover photosynthesis decreased by nearly 50% under drought, accompanied by a reduction in leaf water status (water potential) by more than one third. In contrast, strawberry clover maintained a higher water status, photosynthesis and transpiration rate under drought than white clover. In addition, we observed drought-induced reductions in white clover leaf quality, including lower nitrogen levels. We conclude that strawberry clover displays drought resistance in a number of key leaf parameters. The findings suggest value in testing strawberry clover as a complement or alternative to white clover in droughtprone pasture environments. Keywords: drought, strawberry clover, Trifolium fragiferum L., Trifolium repens L., white clover

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Global-scale structure of the eelgrass microbiome

10.1101/089797 ◽

2016 ◽

Cited By ~ 3

Author(s):

Ashkaan K Fahimipour ◽

Melissa R Kardish ◽

Jonathan A Eisen ◽

Jenna M Lang ◽

Jessica L Green ◽

...

Keyword(s):

Microbial Communities ◽

Spatial Scales ◽

Metabolic Modeling ◽

Global Scale ◽

Functional Roles ◽

Spatial Turnover ◽

Sulfur Oxidizing ◽

And Performance ◽

Occurrence Patterns ◽

Root Surfaces

AbstractPlant-associated microorganisms are essential for their hosts' survival and performance. Yet, most plant microbiome studies to date have focused on terrestrial plant species sampled across relatively small spatial scales. Here we report results of a global-scale analysis of microbial communities associated with leaf and root surfaces of the marine eelgrassZostera marinathroughout its range in the Northern Hemisphere. By contrasting host microbiomes with those of their surrounding seawater and sediment communities, we uncovered the structure, composition and variability of microbial communities associated withZ. marina. We also investigated hypotheses about the mechanisms driving assembly of the eelgrass microbiome using a whole-genomic metabolic modeling approach. Our results reveal aboveground leaf communities displaying high variability and spatial turnover, that strongly mirror their adjacent coastal seawater microbiomes. In contrast, roots showed relatively low spatial turnover and were compositionally distinct from surrounding sediment communities — a result largely driven by the enrichment of predicted sulfur-oxidizing bacterial taxa on root surfaces. Metabolic modeling of enriched taxa was consistent with an assembly process whereby similarity in resource use drives taxonomic co-occurrence patterns on belowground, but not aboveground, host tissues. Our work provides evidence for a coreZ. marinaroot microbiome with putative functional roles and highlights potentially disparate processes influencing microbiome assembly on different plant compartments.

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