Copper and other minerals in herbage species and varieties on copper-deficient soils

The mineral composition of Lolium perenne, Dactylis glomerata, Trifolium repens, Lotus corniculatus and six non-leguminous broadleaved herbs was determined at two sites on copper-deficient soils with and without soil-applied copper sulphate at 2 kg Cu ha^-1. D. glomerata was richer than Lolium perenne in P, Mn and Cu, and T. repens was richer than either grass species in Ca, P, Mg and Cu. D. glomerata cultivars differed in Ca, P, Na and Mg concentrations, and L. perenne cultivars in Ca concentration. Lotus corniculatus contained less Ca, P, Na and Mn but more Zn than T. repens. Achillea millefolium was rich in K, Cichorium intybus in K, Mg and Zn, Petroselinum crispum in Na and Zn, Rumex acetosa in K, P, Mg and Zn and Taraxacum officinale in Na, Mg and Zn. Rumex was low in Na and Plantago lanceolata in Na and Mn. None of these herbs was richer than T. repens in Cu. Copper sulphate application raised the Cu concentration of the herbage only slightly, species or varieties differing little in their response to applied Cu. It is concluded that adjustment of botanical composition, with or without copper sulphate application, will not help to prevent hypocupraemia in grazing stock.     

Response of permanent and reseeded grassland to fertilizer nitrogen. 1. Herbage production and herbage quality

The productivity of permanent swards of mixed species composition was compared with that of sown Lolium perenne , cv. Melle at five fertilizer-N rates (0, 150, 300, 450 and 900 kg N ha⁻¹) and with L. perenne/Trifolium repens , cv. Grasslands Huia at 0 kg N ha⁻¹. The investigation was conducted under two cutting frequencies at sixteen sites in England and Wales, representing a range of grassland environments.
Annual total herbage dry matter (DM) production from both permanent and reseeded swards increased with successive increments of fertilizer-N up to 450 kg N ha⁻¹. Herbage DM production from reseeded swards in the first year after sowing was signficantly higher than from the permanent swards, at all fertilizer-N treatments. In subsequent years the production advantage of the L. perenne reseeds was maintained only at the higher N rates, though sown L. perenne/T. repens was the most productive sward type at 0 N. Average differences in modified acid-detergent fibre suggested small advantages in herbage quality to the reseeded swards.
It is concluded that, while reseeded swards are more productive in the year after sowing, many permanent swards are capable of high levels of production and that reseeding to a L. perenne sward cannot always be justified, particularly for grassland receiving low or moderate inputs of fertilizer-N.     

Concentrations of N, P, K, Ca, Mg and Na in perennial ryegrass and white clover leaves of different ages

Leaf blades of perennial ryegrass ( Lolium perenne ) at five developmental stages, from unemerged to dead, were collected from cut swards grown under field conditions. Similarly, leaflets of white clover ( Trifolium repens ) at four developmental stages, from tightly folded to proximal to the youngest fully developed leaf, were collected. The leaves were analysed for N, P, K, Ca, Mg and Na.
In perennial ryegrass, the concentration of N declined by about half and those of P and K declined by about two-thirds, as leaves aged. By contrast, the concentration of Ca increased more than fivefold and that of Mg about twofold as leaves aged. The concentration of Na initially increased more than twofold but then declined as leaves died. In white clover the concentration of N declined by about 20% as leaves aged, while the concentrations of P and K declined by about 50%; the concentration of Ca increased about fivefold, that of Mg declined by about 15% and that of Na increased by about 15%.
The application of N increased the concentrations of N and K in ryegrass leaf blades at all stages of development. The application of P increased the concentrations of P and Na in the leaves of both species.     

Herbage productivity of brome grass (Bromus carinatus)

Herbage production and quality of swards of brome grass (Bromus carinatus. Hook and Am) were compared with other commonly sown grasses at two sites in Scotland. At Ayr, the comparison was with perennial ryegrass ( Lolium perenne L.), cocksfoot ( Dactylis glomerata L.) and timothy ( Phleum pratense L.) under 6-cut (experiment 1) and 4-cut (experiment 2) regimes over 3 years with 360 kg ha⁻¹ fertilizer N applied annually in each experiment. At Edinburgh, brome grass was compared over 3 years with perennial ryegrass and cocksfoot under a 7-cut system given 3(X)-35O kg N ha⁻¹ year⁻¹ (experiment 3) and with perennial ryegrass, cocksfoot and Italian ryegrass ( Lolium multiflorum Lam.) under a 4-cut system given 250–325 kg N ha⁻¹ annually (experiment 4).
Over the 3 years, brome grass gave 1.18, 6.19 and 1.3% less dry matter (DM) production than the other grasses in experiments 1, 2 and 3 respectively; in experiment 4, it was 1 % less productive than Italian ryegrass but 1.2% more productive than the other grasses. The organic matter digestibility (OMD) of brome grass was lower than that of perennial ryegrass but higher than timothy at Ayr, similar to perennial and Italian ryegrasses at Edinburgh but markedly superior to cocksfoot at both sites. N concentrations in brome grass were higher than in the ryegrasses but lower than in cocksfoot. Mineral composition data showed brome grass to be high in P and K, low in Ca and Mg and very low in Na compared with corresponding concentrations in the other grasses.
The variable performance of this brome grass species ( B. carinatus ) against commonly used grasses in the reported experiments, together with similar evidence from the literature, leads to the conclusion that it is unlikely to be suitable for widespread use in the UK; nevertheless, it has shown some promise in drought-prone situations.     

South-west England grassland survey 1983

A survey of grassland on 127 farms in south-west England was conducted in order to investigate the cutting and grazing management of grassland, botanical composition and the use of fertilizer N, and to quantify recent trends in reseeding and the age structure of swards. Twenty-six percent of the grassland surveyed was classified as arable grassland (in rotation with crops) and 74% as permanent grassland. Only 37% of the established grassland on dairy farms was aged over 20 years compared with 53% on livestock farms. Mowing was practised on 52% of the grassland, two-thirds of it every year, and virtually all grassland was grazed for part of the year. The average fertilizer N input was 168 kg ha⁻¹ with considerable variation with sward age (average 113 kg ha⁻¹ for over-20-year-old swards) and between dairy farms (average 217 kg ha⁻¹) and livestock farms (100 kg ha⁻¹)- The average proportion of sown species (mainly Lolium perenne) ranged from 90% in young swards to 36% in swards aged over 20 years, with considerable variation within age groups. L. perenne was associated with high inputs of fertilizer N, good drainage, sheep grazing and organic manures, e.g. among swards aged over 20 years it contributed 38% on average where >250 kg N ha⁻¹ were applied, but only 12% where no fertilizer N was applied. A continuous network of Trifolium repens occurred in 27% of the grassland–this was associated with low inputs of fertilizer N, good drainage and sheep grazing. Agrostis spp. were the most abundant unsown species and Cirsium arvense, Ranunculus spp. and Rumex spp. the most common broad-leaved weeds. Features of the sample are compared with those in the south-west England region and in England and Wales as a whole.     

Botanical composition of permanent grassland in England and Wales in relation to soil, environment and management factors

Grassland in England and Wales accounts for nearly 60% of the enclosed agricultural land and approximately 50% is at least 20 years old. Botanical composition, especially amongst older grassland, is extremely variable.
A survey of 502 grassland farms was conducted in the 1970s. Factors affecting botanical composition of individual fields have been investigated using correlation and regression analyses and swards of similar botanical composition grouped using cluster analysis. Lolium perenne, Agrostis spp. and Holcus lanatus were numerically the most important species, contributing, on average, 35%. 21% and 10%, respectively. Most older swards contained Lolium perenne and Agrostis spp. in varying proportions depending on drainage, soil fertility and management. Swards containing a significant proportion of Trifolium repens were associated with adequate drainage, good soil nutrient status, low inputs of fertilizer nitrogen and hard grazing. Of the other common species Holcus lanatus was associated with poor drainage, low soil fertility, hay cutting, short-season grazing and low fertilizer N. Festuca rubra was mainly in older swards, at higher elevations and with low fertilizer N but heavy stocking. Swards containing Rumex spp., Poa trivialis and other sown grasses were associated with mowing together with reasonably high soil fertility.     

Assessment of contrasting perennial ryegrasses, with and without white clover, under continuous sheep stocking in the uplands. 5. Herbage production, quality and intake in years 4–6

Herbage characteristics were studied over years 4–6 (1988–90) in three perennial ryegrass ( Lolium perenne L.) varieties as grass-only (200 kg N ha^-1) and grass/clover ( Trifolium repens L.) swards which received 75kg N ha^-1 in 1988 and 0kg N ha^-1 in 1989 and 1990 when continuously stocked with sheep. Mean total annual herbage production of Aurora, a very early flowering variety, was 11% more than that of late-flowering Aberystwyth S23 due to 21% higher growth as grass/clover pasture. The grass/clover sward of Meltra, a tetraploid late-flowering variety, out-yielded S23/clover by 17%. Herbage production of grass/clover was 86% of that of grass only in 1988 but only 54% of the grass-only swards averaged for 1989 and 1990.
In vitro organic matter digestibility (OMD) of Meltra was 38g kg^-1 OM and 27g kg^-1 OM higher than that of S23 and Aurora respectively. OMD of grass/clover was 15g kg^-1 OM higher than that of grass only during the post-weaning period. Herbage intake was positively correlated with OMD of herbage.
The herbage attributes were related to lamb performance reported previously. Lamb output was positively correlated with intake of digestible organic matter.
Differences between the three varieties in herbage characteristics were greater as grass/clover than as grass-only swards, reflecting their compatibility with white clover. In this respect Meltra was the best and S23 the poorest variety.     

The fitting of frequency distributions to height measurements on grazed swards

Herbage height was measured in ryegrass/white clover ( Lolium perenne/Trifolium repens ) swards grazed by cattle using the rising plate meter or the sward stick. Ordinary single normal and double normal distributions were fitted to the data obtained. After the first 6 weeks of continuous grazing the double normal distributions fitted data for the taller swards better than the single normal distribution did, but for a short sward there was no improvement. There was no improvement due to the use of the double normal distribution with data for swards grazed by sheep.     

氮磷钾肥对稻米铁、锌、铜、锰、镁、钙含量和产量的影响

 采用田间试验，在四川省西昌市用两个水稻品种研究了氮、磷、钾肥施用量对稻米中铁、锌、铜、锰、镁、钙含量和产量的影响。结果表明，稻米中铁、锌、铜、锰、镁、钙含量均随着施氮量增加先上升后下降，滇屯502的铁、锌、铜、锰、镁、钙含量和产量都以施用90 kg/hm2 N最高，稻谷产量以施用180 kg/hm2 N最高；而合系39的铁、锌、铜、锰、镁、钙的含量以施用180 kg/hm2 N最高，稻谷产量以施用270 kg/hm2 N最高，说明供试籼型品种滇屯502对氮肥的敏感性较粳型品种合系39强；磷肥明显降低了稻米中铁、铜、锰、钙的含量和产量，适量增施磷肥有利于增加稻米中镁的含量和产量；适量施用钾肥有利于提高稻米中铁、锌、铜、锰含量和产量，两供试品种铁、锌、铜、锰含量均以90 kg/hm2 K2O时最高，而钾肥明显降低了稻米中镁、钙的含量和产量。     

Effects of application of nitrogen fertilizer on concentrations of P, K, S, Ca, Mg, Na, Cl, Mn, Fe, Cu and Zn in perennial ryegrass/white clover pastures in south-western Victoria, Australia

Effects of timing and rate of N fertilizer application on concentrations of P, K, S, Ca, Mg, Na, Cl, Mn, Fe, Cu and Zn in herbage from perennial ryegrass/white clover pastures were studied at two sites in south-western Victoria, Australia. Nitrogen fertilizer (0, 15, 25, 30, 45 and 60 kg ha^–1) was applied as urea in mid-April, early May, mid-May, early June and mid-June 1996 to pastures grazed by dairy cows. At Site 1, N fertilizer resulted in a linear increase in P, K, S, Mg and Cl concentrations in herbage and a linear decrease in Ca concentration. For all times of application, concentrations of P, K, Ca, Mg and Cl in herbage increased by 0·0048, 0·08, −0·010, 0·0013 and 0·053 g kg^–1 dry matter (DM) per kg N applied respectively. For S concentration, maximum responses occurred in mid-May (0·012 g kg^–1 DM per kg N applied). At Site 2, N fertilizer resulted in a linear increase in P, S and Na concentrations in herbage, a linear decrease in Ca concentration and a curvilinear increase in K and Cl concentration. The maximum responses for P, S and K concentrations in herbage occurred for the N application in mid-June and were 0·015, 0·008 and 0·47 g kg^–1 DM per kg N applied respectively. For Cl concentration, the maximum response occurred for the N application in early June and was 0·225 g kg^–1 DM per kg N applied. Overall, applications of N fertilizer up to 60 kg ha^–1 did not alter herbage mineral concentration to levels that might affect pasture growth or animal health.     

Assessment of contrasting perennial ryegrasses, with and without white clover, under continuous sheep stocking in the uplands. 3. Herbage production, quality and intake

Herbage characteristics were monitored over 3 years (1985–1987) in three perennial ryegrass ( Lolium perenne L.) varieties as grass/only (200 kg N ha⁻¹) and grass/clover ( Trifolium repens L.) (75 kg N ha⁻¹) swards when continuously stocked with sheep. Although mean total annual herbage production was similar from the grass varieties, growth of Aurora, a very early-flowering variety, was higher than that of Aberystwyth S23 and Meltra (tetraploid) late-flowering types in spring. Herbage production from grass-only swards was 15% higher than from grass/clover swards.
In vitro organic matter digestibility (OMD) of Aurora and Meltra was 34 g kg ⁻¹ and 26 g kg ⁻¹ higher ( P < 0·01) than that of S23. Averaged over varieties, the OMD of grass/clover was 25 g kg ⁻¹ higher ( P < 0·05) than grass-only during the post-weaning period. Individual lamb digestible organic matter intake (DOMI) was 22% higher ( P < 0·05) on grass/clover than on grass-only during this period. Water-soluble carbohydrates content of Aurora was 42% higher ( P < 0·001) than that of both Meltra and S23.
Herbage characteristics were related to lamb performance reported previously. Lamb production was positively correlated with DOMI. However, the magnitude of differences in lamb performance between treatments was much greater than the extent of differences detected in herbage characteristics.     

A comparison of two cultivars of Holcus lanatus with Lolium perenne, under cutting

This work examined whether or not Holcus lanatus, cv. Massey Basyn, is an improvement on plants from German Commercial seed of this species and whether either could outyield Lolium perenne cv. Aberystwyth S23. The three grasses were sown in monoculture in a field near Oxford and received a total of either 250 or 500 kg N ha^-1 over two years. They were also sown with Tri-folium repens cv. Blanca. The plots were cut 11 times over the 2-year period at a height of 50 mm from ground level.
At the high rate of nitrogen Lolium perenne always gave the highest yields of DM and DOM. In the second year, both types of H. lanatus gave higher yields than L. perenne at the low level of N. The L. perenne and T. repens mixture yielded more than that with H. lanatus and T. repens. H. lanatus depressed the yield of T. repens more than did L. perenne. H. lanatus h lanatus; Massey Basyn was affected less by rust infection than was German Commercial H. lanatus. At the final harvest, plots with r. repens contained more unsown grass than did N-fertilized plots sown to grasses only.     

Sodium fertilizer application to pasture. 4. Effects on mineral uptake and the sodium and potassium status of steers

Mineral availability and status in body tissues was examined with four rumen-fistulated steers arranged in a Latin-square change-over design. The steers were fed perennial ryegrass herbage from a pasture fertilized with four Na treatments: 0 (Nil), 32 (Low), 66 (Medium) or 96 (High) kg Na ha^-1 yr^-1. Na fertilizer increased herbage contents and intakes of Na, Mg and Ca but did not affect intakes of K, P and S. Herbage K:Na and K:(Ca+Mg) decreased in direct proportion to the amount of Na fertilizer applied. With increasing dietary Na intake, the Na content of saliva increased and the K content decreased. There was an increase in Na and a reciprocal decrease in K contents of rumen fluid with increasing dietary Na. Blood plasma Na contents were greater when the Na-treated herbages were fed than in the Nil treatment. There was no effect of treatment on blood plasma K content. Increasing dietary Na increased urinary Na but did not affect urinary K. Faecal mineral concentrations of Na, Ca, P and S were increased by increasing dietary Na, whereas K content was reduced and the Mg content was unaffected. There was no difference between treatments in the proportion of mineral rapidly solubilized, except Na which increased with increasing dietary Na content. The fractional rate of degradation was greater for Na, K, and Mg than for Ca and P. Based on effective solubilization, minerals were ranked in the order K > (Mg = Na) > Ca > P, and treatments were in the order Medium > (High = Low) > Nil. Increasing Na intake increased Ca but not P or Mg availability and increased the uptake of all three minerals.     

STUDIES IN RESPONSE TO NITROGEN

Data are presented demonstrating the effects of applying fertilizer N at 59, 118 or 177 kg/ha on 16 Apr. on uptake of K, P. Ca, Mg and Na in primary growth (PG) harvested 8, 12, 16, 23, 29, 45 and 57 days afterwards, and residual effects in two successive regrowths (RG1 and RG2) harvested on 12 June and 13 Aug., respectively. Significant residual responses as uptake of K, P, Ca, Mg and Na were shown in RG1 and RG2 after all dates of harvesting PG. The residual responses compensated for poor uptake in PG. Thus, low uptakes to the second increment of N were followed by high residual responses in both regrowths; and low uptakes in PG harvested shortly after applying the fertilizer N were followed by high residual responses. Averaged over the seven dates of PG harvest, the sum of responses (PG+RG1+RG2) to the second N increment was greater than total response to the first increment in P and Mg, considerably greater in Ca and Na and slightly lower in K. These marked residual responses to the second N increment were most noticeable where PG was harvested 23 days after applying fertilizer N and became less marked as date of PG harvest was advanced. Percentage K, P, Ca, Mg and Na in DM of the PG and of RG1 increased as N application was raised. By RG2, the residual effects of fertilizer N on percentage K. P and Mg were reversed to give reduced percentages with increased N application to PG. indicative of deficiencies in availability of these elements. The application of 177 kg N/ha to PG resulted in the release of additional soil N and of other mineral elements which could lead to their depletion.     

Multivariate analysis of relationship between potato (Solanum tuberosum L.) yield,amount of applied elements,their concentrations in tubers and uptake in a long-term fertilizer experiment

The aim of this study was to investigate how potato yield, the concentrations of elements (N, P, K, Ca, Mg, S, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in tubers and their uptake are affected by mineral N, P and K fertilizers, straw and pig slurry application.     

铜与锌对茶树生育特性及生理代谢的影响Ⅲ．施铜对茶树体内铜及其他矿质元素吸收的影响

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Potential of imaging spectroscopy as tool for pasture management

The use of imaging spectroscopy to predict the herbage mass of dry matter (DM), DM content of herbage and crude fibre, ash, total sugars and mineral (N, P, K, S, Ca, Mg, Mn, Zn and Fe) concentrations was evaluated. The experimental system used measured reflectance between 404 and 1650 nm at high spatial (0·28–1·45 mm²) and spectral resolution. Data from two experiments with Lolium perenne L. mini‐swards were used where the degree of sward damage or N‐fertilizer application varied. Regression models were calibrated and validated and the potential reduction in prediction error with multiple observations was estimated. The mean prediction errors for DM mass, DM content and N, total sugars, ash and crude fibre concentrations were 235–268 kg ha^?1, 9·6–16·8 g kg^?1, 2·4–3·4 g kg DM^?1, 16·2–27·7 g kg DM^?1, 5·8–6·5 g kg DM^?1 and 8·4–10·4 g kg DM^?1 respectively. The predictions for concentrations of P, K, S and Mg allowed identification of deficiency levels, in contrast to the concentrations of Na, Zn, Mn and Ca which could not be predicted with adequate precision. Prediction errors of DM mass may be maximally reduced to 95–142 kg ha^?1 with 25 replicate measurements per field. It is concluded that imaging spectroscopy can provide an accurate means for assessment of DM mass of standing grass herbage. Predictions of macronutrient content and feeding value were satisfactory. The methodology requires further evaluation under field conditions.     

粳稻“龙锦1号/香软米1578” F3家系群糙米矿质元素含量变异及相关性分析

 利用粳稻品种间杂交组合“龙锦1号/香软米1578”的196份F3家系,对糙米中Fe、Se、Zn、Cu、Mn、Ca、Mg、K、Na和P等10种矿质元素含量的变异及其相关性进行了分析。 10种矿质元素在F3家系间均有较大的变异,其中Na含量变异最大,Zn含量变异最小,变异系数分别为77.69％和12.04％。各矿质元素含量的变异系数大小顺序为Na>Se>Cu>Fe>Mg>Mn>Ca>P>K>Zn。不同矿质元素含量也有较大的差异,F3家系群各矿质元素含量平均值高低排序为P>K>Mg>Ca>Fe>Mn>Zn>Na>Cu>Se。糙米中10种矿质元素含量在F3家系群中均表现为正态分布,为由多基因控制的数量性状。Zn与Fe、Cu,Mn与Mg、Ca、K、P,Ca与Mg、K、Na、P,Mg与K、P,P与K、Na含量呈显著或极显著正相关,而Fe与Se、Mn与Na、Mg与Na含量呈显著或极显著负相关。Mn、Ca、Mg、K、P含量与其他矿质元素含量间的相关关系较Fe、Se、Cu、Zn含量与其他矿质元素含量间的相关关系更为密切。     

1986 survey of upland grassland in England and Wales: changes in age structure and botanical composition since 1970–72 in relation to grassland management and physical features

A sample of 10000 ha of grassland in seven upland districts originally surveyed in 1970–72 was re-surveyed in 1986. Forty percent of the area was above 240 m elevation, 38% had gradients above 81/2°, 29% had poor or bad drainage and 54% was classified as having difficult or severe limitations to management. Twelve percent had been reseeded within the previous 5 years and 39% within 20 years; 6% was classified as arable grassland (in rotation with crops). Thirty-four percent was usually mown, two-thirds of it for silage. In most years 72% of grassland received fertilizer N (average application 123 kg N ha⁻¹) and 35% received organic manure; nearly 20% received neither. Older swards tended to receive lower rates of fertilizer N than reseeds, hay fields and grazed fields less than silage fields, and fields on beef/sheep farms less than those on dairy farms. The proportion of sown species in swards averaged 35%, of which Lolium perenne accounted for 23%. A good contribution of Trifolium repens was recorded in 15% of the grassland. Herb species were recorded in 30% of the grassland, mostly in situations with low fertilizer N under hay or grazing. Agrostis spp., Poa spp., Holcus lanatus and Festuca rubra were the main unsown grasses. The average contribution of L. perenne had increased since 1970–72; it was also present in two-thirds of the area from which it was absent in 1970–72, whilst the contribution of T. repens had decreased. The incidence of Cirsium arvense and Ranunculus spp. had also decreased, whilst that of Pteridium aquilinum had increased.     

Animal production evaluation of herbage varieties. 1. Comparison of Aurora with Frances, Talbot and Melle perennial ryegrasses when grown alone and with clover

Comparative herbage characteristics and sheep production (ewes and lambs until weaning and lambs thereafter) from swards of Aurora (very early flowering), Frances (early flowering), Talbot (intermediate flowering) and Melle (late flowering) varieties of perennial ryegrass ( Lolium perenne ) were studied under a continuous variable stocking management based on sward surface height guidelines. The varieties were assessed as grass-only (215 kg N ha⁻¹ fertilizer) and grass/clover (83 kg N ha⁻¹ fertilizer) pastures.
Over 2 years (1985-86) total annual lamb production per hectare from grass-only swards of Aurora was 19% more than that from Frances despite similar herbage productivity. Differences between the varieties in lamb output were more pronounced as grass/clover swards, with Aurora producing 29 and 18% more lamb than Melle and Talbot respectively and with Frances also giving 16% more than Melle. Overall lamb production from grass/clover swards was 10% more than that from the grass-only pastures, mainly due to 69% advantage in individual lamb growth rates after weaning. Herbage organic matter digestibility, during the post-weaning period, was higher on grass/clover than on grass-only swards, and similarly with Aurora versus the other varieties. Under a frequent cut simulated grazing regime the relative herbage productivity of the four varieties differed, with Aurora 13% less productive than Frances.
The results are discussed in relation to the limitations of assessing performance under cutting, and the significance of the interaction in animal productivity between the two sward types.