bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparison of the effects of prilled urea, used alone or with a nitrification or urease inhibitor, with those of ‘Nitro-Chalk’
Authors: Rodgers G. A. , Penny A. , Hewitt M. V. 
Published: March 2009

SummaryPrilled urea, with or without a nitrification inhibitor (dicyandiamide, DCD) or urease inhibitor (hydroquinone), was compared with ‘Nitro-Chalk’ as a nitrogen fertilizer for winter oil-seed rape in field experiments on a clay loam soil at Rothamsted in 1984 and 1985. Each was tested when supplying 50 kg N/ha to the seed bed; each was also broadcast in early spring to supply 150 kg N/ha as either a single dressing or two equal dressings, the form of nitrogen being the same as that applied in the seed bed.Seed-bed nitrogen increased plant growth during autumn and winter in both years but increased yield only in 1985.Scorching of plant leaves was severe in spring after application of urea or urea plus DCD given as a single dressing, but was much less with urea plus hydroquinone or when the dressings were divided. DCD inhibited nitrification of fertilizer nitrogen but had little effect on yield compared with urea alone. Ammonia volatilization losses were reduced by urea plus hydroquinone but, irrespective of the type of fertilizer applied, loss was always less than 3% of the nitrogen applied. Soil pH rose rapidly after urea application and thereafter fell slowly, whereas pH fell immediately after application of ‘Nitro-Chalk’. Neither dicyandiamide nor hydroquinone affected the pH changes after urea application. Overall, grain yields from urea were 90%, whereas those from urea plus hydroquinone were 97%, of those obtained from ‘Nitro-Chalk’. Dividing the spring dressings of urea-nitrogen increased yield in 1985 compared with a single dressing, but not in 1984. Yields from divided and single dressings of ‘Nitro-Chalk’ were similar. Oil and protein yields generally showed the same patterns of response to the fertilizer treatments as were shown by grain yields.
Variation in the complete diet composition given during the winter period to an autumn-calving herd
Authors: Kroll O. , Owen J. B. , Whitaker C. J. 
Published: March 2009

SUMMARYAutumn-calving cows on a complete diet system were given a similar amount of concentrates over two winter periods in the years 1980–1 and 1981–2. Two feed allocation systems were examined: step (different diets given at different stages of lactation) and uniform (one single diet given over all the winter period).The yield of fat-corrected milk (FCM) was similar (P > 0·05) in both systems with 5·32 and 5·37 t/cow for the step and uniform system respectively in the 1st year and 4·75 and 4·35 t/cow in the 2nd year.There is an indication that adult cows or cows with a higher potential for yield can respond to the higher energy concentration diet given in early lactation but with the main effect on milk, not in FCM yield.No effect of diet distribution was found on overall weight gain but cows given the uniform system lost less weight in early lactation and this may lead to better conception for cows in such a system.
The response of grass-clover and pure-grass leys to irrigation and fertilizer nitrogen treatment. I. Irrigation effects
Authors: Reid D. , Castle M. E. 
Published: March 2009

1. In an experiment conducted at the Hannah Institute the effects of irrigation and fertilizer nitrogen treatments on four sward types were studied for 3 years. The swards were S 23 perennial rye-grass with S 100 white clover, S 23 rye-grass alone, S 37 cocksfoot with S 100 white clover, and S 37 cocksfoot alone.2. The irrigation treatments were—a control (no water) treatment, and two treatments which were irrigated to planned deficit levels of 2 or 0·5 in. below field capacity.
Some comments on the shape of the gain–stocking rate curve
Authors: Connolly J. 
Published: March 2009

SUMMARYIn this paper the method proposed by Jones & Sandland (1974) for testing the linearity of the animal gain–stocking rate relationship is examined. It is shown that the method cannot be used to establish such linearity. An examination of the biases in estimation of optimum stocking rate and gain per animal and per unit area at the optimum stocking rate arising out of assuming linearity where the true relationship was quadratic led to the following conclusions. Quite large biases can arise. Selection of stocking rates straddling the true optimum reduces these biases. If experimental stocking rates are lower than the true optimum stocking rate the optimum stocking rate is overestimated and the animal gain at optimum is underestimated and vice versa if the experimental stocking rates exceed the true optimum rate.
Experiments on the effect of hormone weedkillers on sugar beet
Authors: Byford W. J. , Prince J. 
Published: March 2009

SUMMARYMCPA and 2,4-D sprays at up to 1/20 the dosage normally vised for weed control in cereals severely distorted sugar beet, which subsequently grew at near normal rate but remained distorted. The severity of symptoms and yield depression depended on the stage of growth of the beet when sprayed. Sugar-yield loss was greatest when plants were sprayed at the 6–8 leaf stage.
Removal of phosphorus and potassium from the soil in wheat and barley straw
Authors: Withers P. J. A. 
Published: March 2009

SUMMARYThe median concentration of phosphorus and potassium in a total of 867 samples of wheat and barley straw at harvest in England in 1986–88 was 0·07% P and 1·00% K in the dry matter. Variation was significant between years and between crop species. The concentration of potassium in wheat and barley straw increased with increasing rate of applied nitrogen at 60% of the sites where this was tested. The results have been incorporated into practical recommendation systems for farmers.
Response of rice yields to irrigation and drainage at two phases of growth
Authors: Farah S. M. 
Published: March 2009

In the Sudan, rice has been grown since 1905, but on only a very limited acreage, and information about methods of production are lacking.With the introduction of a large number of rice varieties into the country (Moir, 1965, 1966, 1967, 1968), an irrigation and drainage experiment was initiated by Hack (1968) at Kenana Research Station (KRS). Using the variety H.D.41, he found no advantage from very short watering intervals (1–3 days) in the early stage of growth, i.e. up to the boot stage, whereas better results were obtained from watering every 6 days in the early stage, to obtain a large number of flowers, and every other day in the late stage, to obtain relatively low sterility and large grains.
Flower and pod production at various nodes of Phaseolus vulgaris L.
Authors: Tayo T. O. 
Published: March 2009

SUMMARYIn a glasshouse study, the pattern of flower and pod production at the various flowering nodes of Phaseolus vulgaris (cv. 344) was mapped out. Soft X-radiation techniques were also used to study the development of retained and abscissed pods at the various nodes while varying levels of flower or pod removal were used to study the modification to pod development at each flowering node following organ removal.The period of flower opening over the whole plant spanned an average of 12 days and 90% of the pods retained to maturity were formed from flowers opened within 4 days of anthesis. The terminal inflorescence produced most of the flowers on the plant (25%), but nodes 2 and 3 developed the bulk (50%) of the pods retained. Only 30% of the open flowers on the plant formed pods that were retained to maturity.Pod elongation was initially very rapid in the pods to be retained, following successful fertilization, with the latter period of pod growth devoted almost entirely to seedfilling. A slow growth rate characterizes the development of abscission in Phaseolus pods and the number of seeds per pod is determined later in pod growth.Flower or pod removal prolonged flowering and led to longer leaf retention and more branches on the main stem. The number of mature pods was lower on the treated plants and the more severe the removal the larger were these treatment effects. Plants compensated for fewer pods by having more seeds per pod but these were not enough to prevent significant depression of seed dry weight per plant by the most severe removals. Flower or pod removal led to a shift of emphasis in pod production by the plant from nodes 2 and 3 to other areas of the plant where natural wastage of flower and young pods is high.
Effect of seed rate and application of N fertilizer on grain yield and N uptake of rice under intermediate deepwater conditions (15–50 cm)
Authors: Reddy M. D. , Ghosh B. C. , Panda M. M. 
Published: March 2009

SUMMARYIn an intermediate deepwater (15–50 cm) situation, the number of tillers increased with increase of nitrogen fertilizer from 0 to 40 and 80 kg/ha and of seed rate from 100 to 200, 300 and 400 seeds/m2. The tiller mortality due to higher water depth was higher under no-N treatment and under higher seed rates. The number of panicles and grain yield increased significantly with increase in N. Similarly, an increase in the seed rate increased the number of panicles and decreased the number of grains per panicle and panicle weight. The grain yields of the different seed rates were similar. The interaction between N levels and seed rates was not significant.
Chemotaxis ofCicer Rhizobiumstrains to root exudates of chick pea (Cicer arietinumL.) genotypes and their interaction response on nodulation, nodulins, leghaemoglobin and grain yield in calcareous soil
Authors: Rai R. , Prasad V. 
Published: March 2009

SUMMARYTwoRhizobiumstrains were studied for their chemotaxis, nodulation, nitrogenase activity and other endosymbiotic N2-fixing characteristics with two genotypes ofCicer arietinum. Root exudates were found to attractRhizobiumstrains. Nodule-specific root proteins (nodulins) and leghaemoglobin were found to be host-range specific between two strains ofCicer Rhizobium. Physiologically active iron content was more important for nodule functioning than total iron concentration of nodules.
Effects of nitrogen fertilizer applied to seed crops on seed yields and regrowth of progeny tubers in potatoes
Authors: O'Brien P. J. , Allen E. J. 
Published: March 2009

SUMMARYThree experiments, carried out in 3 years (1972–5), which examined the effects of a wide range of rates of nitrogen fertilizer applied to seed crops of Home Guard on seed and progeny crop growth are reported. There was little effect of increasing rate of N application over the range 0–300 kg/ha on seed yield, and the results suggested that very low rates of nitrogen fertilizer (< 75 kg/ha) were required for maximum seed yield in mid-Wales. Increasing the rate of nitrogen fertilizer above 304 kg/ha delayed growth and decreased yield in seed crops. Although increasing the rate of nitrogen fertilizer in seed crops delayed senescence and increased the nitrogen concentration of tubers, there were few consistent effects on sprouting or growth of progeny crops.Close negatively quadratic relationships were found between the dry-matter content of tubers and their size. The dry-matter content of all sizes of tubers increased during growth, but there were no effects of nitrogen on dry-matter content.
Genetic conservation of rare British sheep: the Portland, Manx Loghtan and Hebridean breeds
Authors: Hall S. J. G. 
Published: March 2009

SUMMARYPedigree analyses were conducted of the Portland, Manx Loghtan and Hebridean sheep. These breeds are kept in small flocks, usually with only one ram active. Total population, and number of flocks have grown since registration started in 1975. Gene flow among flocks arisesfrom transfers of rams and of ewes: about 70% of breeding rams and 40% of breeding ewes have been transferred. Between half and three-quarters of the 1984 lamb crop were measurably inbred. More ram lambs are registered than would be expected in commercial practice.About a third of flocks supplied rams to other flocks showing that these breeds do not have a very hierarchical structure. There is, however, a tendency towards hierarchical structure in the Manx Loghtan. A high proportion of the animals registered as foundation stocks in the earlyyears of the Combined Flock Book were represented in the pedigrees of recent lamb crops, i.e. genetic conservation has, on the whole, been achieved.
Adaptation of Medicago rigidula to a cereal–pasture rotation in north-west Syria
Authors: Abd El-Moneim A. M. , Cocks P. S. 
Published: March 2009

SUMMARYThe ley-farming system (integrated cereal and livestock production in which cerealsrotate with self-regenerating pastures) is considered to be of great potential benefit to north Africa and west Asia. In the colder parts of this region (of which north Syria is typical) its application is limited by poor adaptation of commercial medic cultivars (mainly Medicago truncatula and M. littoralis). An extended selection programme hag identified M. rigidula as adapted to the soils and climate of the region but nothing is known of its adaptation to the ley-farming system itself.An experiment which included 23 selections of M. rigidula and one each of M. rotata and M. noeana was conducted over 3 years during which herbage production, seed yield, and the fate of seeds were observed during the 1st year when pastures were established, the 2nd year when wheat was sown, and the 3rd year when the pasture regenerated. Of the 400–800 kg seed/ha produced in the 1st year an average of 87% remained in the soil in spring of the 3rd year. The weight of seed regenerating in the 3rd year varied from 30 to nearly 170 kg/ha, and herbage production, especially in winter, depended heavily on the number of regenerating seedlings. The most productive regenerating pastures produced nearly 2 t/ha of dried herbage by 1 January, and more than 6 t/ha for the whole growing season.The results showed that there was sufficient residual and newly produced seed at the end of the 3rd year to be sure that subsequent regeneration would result in similar herbage yields in the 5th year, and that the pasture was assured of long-term persistence. The significance of this for livestock production is discussed, and it is concluded that the results should encourage further investigation of grazing management and socioeconomic factors seen as constraints to introducing the ley-farming system to north Syria.
Estimation of genetic differences between Mashona bulls from different production systems using an animal
Authors: Khombe C. T. , Hayes J. F. , Tawonezvi H. P. R. , Khombe M. 
Published: March 2009

SUMMARYThis paper reports genetic differences between 20 Mashona bulls from smallholder farms, 14 from Makoholi Research Station, three from commercial farms and two reference sires, in Zimbabwe. An animal model, fitted through the derivative free Restricted Maximum Likelihood program (DFREML), was used to analyse 707 birth weight and 623 weaning weight records. Both the mean breeding values of the reference sires and the ranch bulls were significantly (P < 0·05) higher than the mean breeding values of smallholder bulls for birth weight (by 1·6 and 1·7 kg, respectively) and weaning weight (by 10·4 and 11·0 kg, respectively). However, seven of the 20 bulls from smallholder farms were among the top 45% of bulls with high breeding values for both birth and weaning weight. The mean breeding value of bulls from Makoholi was not different from any of the other groups, for all traits studied. It was proposed that future efforts to form nucleus herds to improve the weaning weights of indigenous cattle should include the genetic pool in smallholder farms.
Rumen fermentation of fresh herbage
Authors: Williams V. J. , Christian K. R. 
Published: March 2009

1. On twelve occasions covering a complete seasonal cycle rumen mierobial end-product concentrations were measured in a group of sheep allowed to graze a pasture for 1 hr. Considerable differences were obtained in the rises in total volatile fatty acid and ammonia after feeding, in average rumen protein nitrogen and in free mierobial count.2. Seven samples of fresh herbage wfere fed to groups of sheep in pens at different levels of intake. Increase in feed intake with five of the herbages produced significant increases in rumen ammonia and total volatile fatty acid and with one herbage there was a significant increase in protein nitrogen. Free mierobial count was measured after feeding three herbages and was found to be independent of intake level.
The value of liquid digested sewage sludge. III. The results of an experiment on barley
Authors: Coker E. G. 
Published: March 2009

In a trial laid out to compare the effects of liquid digested sludge with equivalent nitrogen and phosphate fertilizers as ‘Nitra-shell’ and superphosphate, growth data, and data of grain and straw yield were obtained.Liquid digested sludge increased the dry weight and shoot number at the ‘tillering’ stage, and dry weight and ear number at the flowering stage, more than equivalent fertilizer.By 13 May, sludge-treated plants had absorbed more nitrogen than fertilizer-treated plants. By 19 June this was reversed for the sludge-treated plants had then absorbed 81% of the nitrogen absorbed by fertilizer-treated plants; ripe grain from sludge plots had a lower nitrogen percentage than grain from fertilizer plots.
Time of application and chemical form of potassium, phosphorus, magnesium and sodium fertilizers and effects on the growth, yield and quality of sugarbeet (Beta vulgaris)
Authors: Allison M. F. , Jaggard K. W. , Armstrong M. J. 
Published: March 2009

SummarySummary Between 1985 and 1988, 14 field experiments at different sites in the UK assessed the effect of applying P, K, Na and Mg in autumn, early spring, late spring or as a split application in both autumn and late spring on the growth, yield and processing quality of sugarbeet. Supplementary experiments compared Kaynitro and Chilean nitrate of soda. None of the treatments had any effect on plant population densities, and any differences in sugar yield could be explained by the leaching of Na. The effects on processing quality were inconsistent and unlikely to be of agronomic or economic significance. Generally, Kaynitro and Chilean nitrate of soda performed no better than the other fertilizers so it is unlikely that their extra cost would be justified. Apart from Na, the timing of nutrient application appeared to be unimportant, even on soils of low fertility. However, Na, being very mobile, was best applied in spring.
Variation in seasonal stocking rate and the dynamics of Lotononis bainesii in Digitaria decumbens pastures
Authors: Fujita H. , Humphreys L. R. 
Published: March 2009

SUMMARYPastures of Digitaria decumbens (pangola grass) previously oversown with Lotononis bainesii at Mount Cotton, south-east Queensland, Australia, were grazed by sheep for 3 years (1985–87), using a factorial combination of seasonal variations in stocking rate.Lotononis behaved as a short-lived plant with a mean half-life of 4·2 months (range 1·6–10·3); rate of mortality was positively related to initial seedling density. The proportion of lotononis remained very low for the first 2 years of the experiment, when conditions were unsuitable for large-scale seedling regeneration, which was also limited by the hardness of the seed reserves. Subsequently, lotononis regenerated well in treatments which combined the following features: (i) light grazing (5 sheep/ha) during the main flowering period of spring-early summer, (ii) heavy short-duration grazing in mid-summer to create a ‘gap’ and (iii) medium or heavy (18 or 27 sheep/ha) grazing during late summer-autumn to reduce competition from pangola grass.The ecological niche of lotononis and the possible use of complementary pastures are discussed.
Moisture transport under cyclic trickle irrigations in different textured soils
Authors: Pal D. , Sen H. S. , Dash N. B. , Bandyopadhyay B. K. 
Published: March 2009

SUMMARYMoisture movement through soil under trickle irrigation was studied in the laboratory at the Central Soil Salinity Research Institute, West Bengal, in 1988/89. Using a cylindrical flow model, the finite difference technique was used to compute the 2-dimensional moisture distributions and wetting front advancements in soils with clay contents ranging from 22·1 to 51·8%. Seven-day cyclic irrigations, each day having one on-cycle (infiltration) with a constant trickle discharge of 0·3 litre/h for 12 h and one off-cycle (redistribution) for 12 h, were used with two water qualities, EC 0·15 and 0·64 S/m. Moisture distributions were measured in artificially packed soil columns 60 cm high and 56 cm in diameter. The degree of agreement between the theoretical and observed values was expressed by Relative Error Percent (REP), defined as the difference between the two, divided by the observed value and expressed as a percentage. The mean REP ranged from 0 to 30, 62·5% of the values falling in the range 0–10, 22·5% from 10 to 20, and 15% from 20 to 30, irrespective of soil texture, water salinity or the irrigation cycle used. It was concluded that the theoretical data closely matched the experimental results. The wetting front in the soil columns was defined as the minimum detectable increase in moisture (10-3 cc/cc) from the initial content, and its advancement was calculated over the entire period of on-off cycles. This model was also used to calculate, for one soil, the theoretical moisture distribution under trickle irrigation with simultaneous loss by evaporation, which is an essential component of field moisture balance.
Breed and sex differences in body composition of sheep in relation to maturity and growth rate
Authors: Gaili E. S. E. 
Published: March 2009

SUMMARYTwenty-four lambs (equally representing males and females), born in December 1986, were obtained from each of the Najdi, Awassi and Hejazi sheep breeds kept at the Experimental Station of King Faisal University in Saudi Arabia. The lambs were reared on their dams and fed after weaning on the same diet up to slaughter at 9 months of age. Slaughter and carcass data were analysed for breed and sex differences using the degree of body maturity and growth rate as covariates. After the effects of differences in body maturity and growth rate were removed, significant breed but not sex effects were recorded in skin, feet, carcass and carcass to bone proportions. In Najdi lambs the feet and bone nproportions (g/kg empty body weight) were higher than in Awassi or Hejazi lambs, whereas Awassi lambs possessed lower carcass but higher skin proportions than the other two native breeds.Breed but not sex affected fat distribution. Awassi lambs had higher tail but lower intermuscular fat content (g/kg total body fat) than Najdi or Hejazi lambs. Most body components were significantly related to the degree of body maturity but not to growth rate.