bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lucerne investigations: III. Effect of heat treatment on germination and field establishment of lucerne seed
Authors: Zaleski A. 
Published: March 2009

1. Lucerne seed samples of known harvest history were treated by dry heat at various temperatures and durations; their germination capacity, emergence and establishment were tested by laboratory, greenhouse and field establishment tests on heavy Boil during 1952–6 at Cambridge.2. A successful and safe heat treatment was 42° C. for 5 days, increasing the germination by as much as 44% up to about 90% at the cost of hard seed.3. The establishment obtained on heavy soil from treated seed samples, although varying from season to season, was significantly higher (P > 0·001) at all seed rates than that obtained from untreated control samples.4. Significant differences were obtained in germination capacity and establishment between samples harvested at different conditions. High moisture content of seed and high percentage of dark brown seeds was associated with late harvest. Brown seeds had a significantly lower germination capacity than yellow seeds. Only samples with a high initial moisture and high percentage of brown seeds showed a substantial decrease in germination capacity during the storage period of 3 years.5. Although the mean number of plants established is significantly higher for higher seed rates the mean percentage of plants established decreases significantly with higher seed rates and the greatest wastage of seeds occurred at the high seed rate of 15 lb; per acre.6. The viability of seed and speed of germination and of emergence were the most important factors in determining the successful establishment of a crop on heavy soil.7. Hard seed is viable and could germinate and produce seedlings by the end of the season, but only a very small percentage of it could normally be established under field conditions. With untreated seed no significant correlations were established between laboratory germination and field establishment or between laboratory germination and greenhouse emergence, yet there were highly significant correlations in these cases for treated seed. With increased duration of laboratory germination test, corresponding to a decrease in the proportion of hard seed, values of r increased. Correlations between field establishment at three seed rates and greenhouse emergence were significant in the case of both untreated and treated seeds.8. When the hard seeds were added to germination or establishment the relationships between the results of these tests were very close and highly significant correlations were established for both lots of seed, untreated and treated. The high proportion of hard seeds was the main limiting factor preventing a close relation between tests for untreated seed.
The effect of dietary N onin vitrolipolysis and fatty acid hydrogenation in rumen digesta from sheep fed diets high in starch
Authors: Gerson T. , John A. , Sinclair B. R. 
Published: March 2009

SUMMARYFive Romney wethers, fitted with rumen fistulae, were each fed five pelleted diets high in starch (30–50%) containing 0·72, 1·22, 1·72, 2·47 and 3·72% N respectively. Samples of rumen liquor were incubated with glycerol-tri-[1-14C]oleate or with [1-14C]- linoleic acid. The rates of lipolysis or hydrogenation of these substrates were measured. In addition rumen contents of the sheep when fed the 1·22% N diet were incubated with radioactive substrates plus 0, 100 and 200 mg finely ground casein.It was found that there was an approximately linear increase in the rate of lipolysis between 0·7 and 2·5% N. The rate of hydrogenation did not increase below l·2% N and tended to decrease above 2·5% N. The potential for hydrogenation of unesterified linoleic acid was calculated to be 4–6 times greater with all diets except that containing 1·2% N. This may be one explanation for the elevated concentration of the rumen unsaturated fatty acids in sheep fed diets containingca.1–1·5% N.It was also established that the addition of finely ground casein to the incubate was without effect.It was concluded that microbial composition is important in regulating the relative rates of lipolysis and hydrogenation which determined the amount of unsaturated dietary fatty acid present in the rumen.
The availability of iron in certain grass, clover and herb species. I. Perennial ryegrass, cocksfoot and timothy
Authors: Thompson A. , Raven A. M. 
Published: March 2009

1. The availability of iron in three species of grass has been investigated using the rat as the experimental animal.2. Two procedures, namely, the increase in blood haemoglobin concentration, and the gain in total gramme of haemoglobin by nutritionally anaemic rats were employed.3. Inorganic iron, as ferric chloride, was shown to be significantly more available than the iron contained in the three grasses.4. The iron in the grass timothy was found to be significantly more available than that in ryegrass or cocksfoot.5. Possible reasons for the differences in iron availability were discussed.
The magnesium of bone mineral
Authors: Taylor T. G. 
Published: March 2009

1. Fractionation experiments have been described in which powdered bone materials were extracted with dilute acids using three different techniques. Ethylene diamine tetracetic acid (EDTA) was also used in one series of experiments.2. The results suggested that the magnesium of bone is present in two main forms, one relatively soluble and the other relatively insoluble in dilute acids.3. It appeared that a large proportion (at least 70%) of the total bone magnesium was located on the surfaces of the bone crystals either as Mg2+ or MgOH+ ions adsorbed at the primary cation adsorbing centres (the surface phosphate ions of the apatite crystals) or as Mg2+ ions replacing surface Ca2+ ions of the crystal lattice.4. Evidence that magnesium carbonate does not occur in significant amounts in bone salt was obtained.5. These results were discussed in relation to the hypomagnesaemia of lactating cows.6. The carbon dioxide of bone also appeared to be present in two main forms, one relatively soluble and the other relatively insoluble in dilute acids.
Irrigation of grassland
Authors: Low A. J. , Armitage E. R. 
Published: March 2009

Field experiments are described comparing the yield of herbage on a series of grass-clover plots which were irrigated after various deficits had developed. In addition to the irrigation treatments, different rates of nitrogen were applied.The maximum yields were obtained when only small deficits were allowed (maximum pF 3·3). This applied particularly to grass-clover swards to which no nitrogen fertilizer was applied.There was not much reduction in yield on predominantly perennial ryegrass swards liberally supplied with nitrogen when larger deficits were allowed to develop (pF c. 4·0).Estimates of soil water deficit from meteorological data using Penman's method agreed very well with direct measurements.
Effect of body weight at calving on body-weight changes during early lactation and post-partum reproductive performance in buffaloes
Authors: Bhalaru Surinder S. , Dhillon J. S. , Tiwana M. S. 
Published: March 2009

SUMMARYStudies on the effect of body weight at calving on body-weight losses during early lactation and the post-partum reproductive performance of large, medium and small buffaloes revealed that the large buffaloes (weighing more than 550 kg at calving) lost most weight (45·9 kg) and the small buffaloes (weighing less than 475 kg at calving) least weight (4·9 kg) during the first 5 months of lactation. The body-weight loss was maximal in the 1st month of lactation. The reproductive performance (measured as conception rate, number of services per conception and service period) of small buffaloes was significantly (P < 0·05) better than the large buffaloes. These results indicate that body–weight losses during early lactation are affected by the body weight at calving and these losses play an important role in influencing the post-partum reproductive performance. It is therefore suggested that, to improve the reproductive performance, the feeding regimen of buffaloes during pregnancy and after calving should be such that body-weight losses after calving are small.
The inability of horses to absorb calcium from calcium oxalate
Authors: Blaney B. J. , Gartner R. J. W. , McKenzie R. A. 
Published: March 2009

SUMMARYSix horses were fed Setaria sphacelata var. sericea cv. Narok hay in a mineral balance experiment and were in negative calcium balance. This should have ensured maximum efficiency of calcium absorption. Only 6·3% of calcium from a single dose of 1·32 kg calcium oxalate was retained by the horses, which supports the suggestion that horses cannot utilize calcium in tropical grasses if it is present as calcium oxalate crystals.
Effect of simazine and prometryne on the growth and nodulation of chickpea (Cicer arietinum L.)
Authors: Kumar S. , Pahwa S. K. , Promila K. , Sharma H. R. 
Published: March 2009

SUMMARYSimazine and prometryne applied to the soil surface in pots at 1·6 and 3·2 kg/ha. 2 days after sowing, did not affect germination or early seedling growth of chickpea. Reductions were noticed under all treatments in the leaf dry weight after 28 days and in the length of the main stem after 42 days. Dry-matter accumulation in the shoot was drastically reduced with simazine but not with prometryne. All treatments retarded dry-matter accumulation in the roots with time. Prometryne reduced chlorophyll content during early growth stages and simazine during later stages.Growth of the rhizobial culture was reduced with increasing concentrations (1–20 mg/1) of both simazine and prometryne. Root nodule initiation was not affected by either of the herbicides but the later production of new nodules and growth of the nodules were reduced in different degrees by various treatments. Overall nodulation was drastically reduced with simazine. Reductions in nodulation with simazine and prometryne appeared to be primarily a case of general root growth reduction. The pink pigment, leghaemoglobin, did not develop at all in the nodules of simazinetreated plants and its concentration was not affected in the nodules of prometrynetreated plants. The N2-fixing efficiency (acetylene reduction) of the nodules was more in the case of prometryne-treated plants and was nil in the case of simazine-treated ones.
Comparison of direct drilling, reduced cultivation and ploughing on the growth of cereals
Authors: Pollard F. , Elliott J. G. , Ellis F. B. , Barnes B. T. 
Published: March 2009

SUMMARYThe results are reported of two experiments made on a silt loam soil over chalk on downland in southern England. Three primary tillage treatments (ploughing, deep or shallow tine cultivation) were compared with direct drilling for their effects on the growth of spring barley during the years 1969–74 and winter wheat during 1974–8.No significant differences in barley population density or early growth were recorded. In the first 2 years more grain was produced on the shallow tined and direct-drilled plots than on those that were ploughed, but the differences did not persist into subsequent years. The mean yield of each treatment over the 4 years did not differ.Significant differences in population density and winter mortality of wheat occurred but these were not consistently associated with differences in yield. In this crop also the mean yields of the cultivation treatments over the 4 years were not significantly different.It is concluded that choice of primary tillage system on this chalk downland soil was not a significant factor in the production of either spring barley or winter wheat.
Response of dryland wheat to phosphorus fertilizer as influenced by profile water storage and rainfall
Authors: Singh Ranjodh , Chadha R. K. , Verma H. N. , Singh Yadvinder 
Published: March 2009

SUMMARYEffects of phosphorus fertilizer, initial profile water storage and seasonal rainfall on yield and water use by dryland wheat on loamy-sand and sandy-loam soils were studied for a 2-year period (1973–5). Plant available water at seeding varied from 62 to 205 mm, seasonal rainfall varied from 62 to 154 mm and available P status ranged from 9·5 to 18·5 kg P/ha. Four rates of phosphorus 0, 15, 30 and 45 kg P2O5/ha were tested. Available water at seeding, seasonal precipitation and the available P status of soil determined the yield response to phosphorus fertilizer. Response to P application was observed up to 15 kg and 30 kg P2O5/ha in loamy-sand and sandy-loam soils respectively. Growth and yield of wheat were highly correlated with the available water at planting plus seasonal rainfall. Total water use did not change in loamy-sand soil, but it increased by 16 mm in sandy-loam soil with the application of phosphorus. The profile water depletion pattern, further, indicates that the fertilized crop used more water from layers below 135 cm in loamy-sand and 22·5 cm in sandy-loam soil.
Effect of potassium and magnesium application to soils on the dry-matter yield and cation composition of maize
Authors: Bedi A. S. , Sekhon G. S. 
Published: March 2009

SUMMARYIn a glasshouse experiment, fertilizer potassium and magnesium were applied in various amounts to 20 soils differing in the proportion of exchangeable potassium to the sum of the three exchangeable cations, potassium, calcium and magnesium. Maize, cv. Ganga-5, was grown as the test crop.In soils where the exchangeable cation ratio (K/Σ (K + Mg + Ca), in equivalents) was less than 0·025, potassium fertilizer significantly increased the dry-matter yield of maize. In soils where this ratio was between 0·026 and 0·05, application of potassium fertilizer was beneficial only up to the intermediate amount of 11 mg K/kg soil. Beyond this amount of application, addition of magnesium was necessary to increase yields. In soils where this ratio exceeded 0·05, potassium fertilizer reduced yields.An optimum ratio of exchangeable calcium, magnesium and potassium appears more important than their absolute amount. Magnesium application to high-potassium soils improved the cation equivalent ratio within the plant and the dry-matter yield.
Glutamate and glutamine metabolism in the ovine placenta
Authors: Pell Jennifer M. , Jeacock Marjorie K. , Shepherd D. A. L. 
Published: March 2009

SUMMARYThe concentration of glutamate and of glutamine was measured in whole blood obtained from a maternal artery, a uterine vein, a foetal artery and an umbilical vein of chronically catherized ewes and foetuses from 100 to 140 days after conception. The activities of glutamate dehydrogenase, phosphate-dependent glutaminase, phosphateindependent glutaminase, glutamine synthetase, γ-glutamyl transferase and glutamine-oxo-acid aminotransferase were measured in placentomes obtained from ewes during a similar period of gestation.The concentrations of glutamate in blood from maternal vessels remained constant, whereas there was a significant decline (P< 0·001) in the concentration of glutamate in foetal blood. Glutamine concentrations declined significantly (P< 0·05) in maternal blood and in foetal arterial blood (P< 0·001), whereas the concentration of glutamine in umbilical venous blood remained constant.Mean arterio-venous differences for glutamate indicated that there was no net uptake from or release into maternal blood by the uterus. However, there was a significant (P< 0·02) uptake of glutamate by the placenta from the foetal circulation. Glutamine release from the placenta into the foetal circulation increased as the foetus matured.Significant activities of glutamate dehydrogenase, γ-glutamyl transferase, glutamine synthetase and phosphate-dependent glutaminase were found in the placenta but there was no significant relationship between the activities of these enzymes and the gestational age of the foetus. The enzyme profile indicated that the placenta has a substantial potential for net glutamine synthesis.It is concluded that, for a 140-day foetus, the release of glutamine from the placenta accounts for more than half of its nitrogen requirement. Direct placental transfer of glutamine from maternal blood accounts for only one-third of the glutamine released by the placenta into the foetal circulation of a 140-day foetus. Therefore, the remainder of the glutamine is synthesized in the placenta from glutamate. Only one-third of the glutamate required for this placental glutamine synthesis is from the glutamate released by the foetus. The remainder must be derived either from 2-oxoglutarate, as the result of aminotransferase or glutamate dehydrogenase activities, or from glutathione by the action of γ-glutamyl transferase.
The development of winter wheat in the field. 2. The control of primordium initiation rate by temperature and photoperiod
Authors: Baker C. K. , Gallagher J. N. 
Published: March 2009

SUMMARYA scheme was developed to describe how the rate at which apical primordia are initiated in cereals depends on temperature and photoperiod. It was used to analyse initiation in field crops of winter wheat (Triticum aestivum L., cv. Maris Huntsman).For the initiation of leaves and spikelets, a straightforward linear regression of initiation rate R against mean air temperature (Ta) gave base temperatures (Tb) close to 0 °C for leaves and for spikelets. However, initiation rate was also correlated with mean photoperiod (P) and base photoperiods (Pb) of –0·5 h and 4h were established for leaf and spikelet initiation. When R was correlated with the index (T – Tb) (P – Pb), r2 was 0·62 for both leaves and spikelets.
The growth and development of cowpeas (Vigna unguiculata)under tropical field conditions: 2. Accumulation and partition of dry weight
Authors: Littleton E. J. , Dennett M. D. , Monteith J. L. , Elstonff J. 
Published: March 2009

SUMMARYThe pattern of dry weight accumulation and partition of cowpea crops grown in Nigeria is described. For the first 50 days, increase in dry matter was proportional to intercepted radiation. Differences in dry weight between crops were due equally to variations in incident solar radiation, the fraction of this radiation intercepted, and the efficiency with which it was used. The variation in total pod weight from 206 to 312 g/ma resulted from differences in number of pods, mean pod weight being constant. The pod weight ratio was relatively constant and there was a strong relationship between final number of pods and total plant dry weight.
Differential susceptibility to pest damage in agricultural grasses
Authors: Henderson I. F. , Clements R. O. 
Published: March 2009

SUMMARYPlots were sown with six varieties of perennial ryegrass, one each of Italian, Westerwolds and hybrid ryegrass, and one each of cocksfoot and timothy, in April 1974. D.M. yield was assessed at four cuts each year, on plots receiving 300 kg N/ha annually, for 4 years. Invertebrate populations and plant survival were monitored at intervals. Half the plots were treated regularly from sowing onwards with the systemic insecticide, phorate. Insecticide treatment increased output generally, but the extent varied from year to year and between grass varieties. The persistence of Italian and hybrid ryegrass varieties was dramatically improved by insecticide treatment. The three diploid varieties of perennial ryegrass studied appeared to be less susceptible to pest damage than the three tetraploid varieties. Shoot-fly larvae (Diptera: Chloropidae) were the major obvious cause of damage.
The effect of nitrogen on cereal yields
Authors: Bullen E. R. , Lessells W. J. 
Published: March 2009

This paper provides a general review of the effect of nitrogenous fertilizers on the yields of wheat, barley and oats. The results of 270 experiments carried out during the last decade in England and Wales have been examined.With the exceptions noted below wheat and barley crops have produced a grain response of 3·0–3·5 cwt./acre to a standard dressing of 0·25 cwt. N/acre; this agrees well with earlier results obtained by Crowther & Yates. The widely grown winter wheat varieties, Hybrid 46, Cappelle Desprez, Bersée, Nord Desprez and Atle each produced an average response of more than 4·0 cwt./acre to the standard dressing. Of the spring barleys, Kenia, Proctor and Herta are also of greater than average responsiveness. The average response of spring oats to the standard dressing was only 1·2 cwt./acre.The number of experiments is insufficient to allow precise conclusions to be drawn on the effect of autumn dressings, but the evidence suggests that in the drier eastern counties autumn nitrogen may give as good a response as the equivalent spring application. Small dressings of nitrogen provide equal responses whether applied early or late in spring; larger applications need to be applied early in spring (March or April) to obtain the highest yields. There is no evidence that divided dressings are more efficient than a single dressing applied in early spring.For highly responsive varieties of winter wheat and spring barley mentioned above a dressing of 0·6–0·7 cwt. N/acre is recommended, producing a net return of approximately £10 per acre. For other varieties of winter wheat, and for spring wheat and spring barley, the recommended dressing of 0·5 cwt. N/acre produces a net return of about £5 per acre.
The effect of formaldehyde treatment of soya-bean meal and rapeseed meal on the amino acid profiles and acid-pepsin solubility of rumen undegraded protein
Authors: Varvikko T. , Lindberg J. E. , Setälä J. , Syrjälä-Qvist Liisa 
Published: March 2009

SUMMARYSoya-bean meal and rapeseed meal treated with 0, 0·4 or 0·8 g formaldehyde/100 g crude protein (N × 6·25) was incubated in the rumen in nylon bags with 10 and 40 μm aperture.Disappearance of dry matter and nitrogenous compounds was reduced with increasing formaldehyde treatment.The proportion of acid-pepsin soluble nitrogen in the undegraded residues of untreated and treated soya-bean meal was similar to the original samples. For rapeseed meal the proportion of acid-pepsin soluble nitrogen in the undegraded residues decreased with increasing rumen incubation time. This reduction decreased with increasing formaldehyde treatment.Concentration of amino acids in the undegraded residues did not generally deviate from those in the original samples. However, a distinguishable decrease in the methionine concentration was observed in all the rapeseed meal samples and in glutamic acid concentration in rapeseed meal treated with 0 and 0·4 g formaldehyde/100g- crude protein.Most of the changes due to rumen incubation were smaller using the 10 μm bags than using the 40 μm bags. However, the bag pore size did not play a decisive role in the conclusions of the results given.
Nitrogen nutrition and canopy temperature in field-grown spring wheat
Authors: Seligman N. G. , Loomis R. S. , Burke J. , Abshahi A. 
Published: March 2009

SUMMARYThe canopy of spring wheat grown with an ample supply of nitrogen was generally cooler than the canopy of a nitrogen-deficient crop. The warmer canopy matured 3–5 days earlier. The accumulated temperature difference was sufficient to account for the different times taken to reach maturity.