bluuebunny/crossref_metadata_2025_split huggingface dataset:
Results from experiments measuring the effects of large amounts of an NPK fertilizer on yield, tuber size and N, P and K contents of three potato varieties
Authors: Widdowson F. V. , Penny A. 
Published: March 2009

SUMMARYExperiments with main-crop potatoes were made at Rothamsted and Woburn in 1971 and 1972 to measure the effects of applying four amounts (1260, 1880, 2510 or 3140 kg/ha) of granular NPK fertilizer (containing 13% N, 13% P2O5 and 20% K2O)for two pairs of varieties (Pentland Crown and King Edward at Rothamsted; Pentland Crown and Record at Woburn) planted either 30 or 45 cm apart in the row.Yields of each variety were greatly increased by the first and second increments of fertilizer at each farm each year (mean increases of 5·5 and 5·2 t/ha respectively), but less by the third (2·1 t/ha); total yields were increased from 35·7 t/ha with 1260 kg/ha of fertilizer to 48·5 t/ha with 3140 kg/ha. As yields increased the proportion of small tubers (< 44 mm) decreased, whilst that of medium (44–70 mm) and large (> 70 mm) tubers increased.The removals of N, P and K by each variety of potato were calculated; for those given 2510 kg/ha of 13·13–20 fertilizer, the mean amounts (kg/ha) removed were 154, 20·6 and 242 of N, P and K respectively, or 47, 14 and 58% of the amounts given. A balance sheet showed the amounts remaining in the soil after potato harvest.Winter wheat was grown after the potatoes to value residual N. In 1972, when average amounts of winter rain fell, grain yields were increased by these residues on the heavy Rothamsted soil, but not on the sandy Woburn soil. In 1973, after an unusually dry winter, the residues consistently decreased yields because of lodging, showing that little N had leached during the winter. % N in the grain was increased by the fertilizer residues each year.
The effect of morphactin on the nutrient concentration of snapdragons
Authors: Asif M. I. , Ergenoglu F. 
Published: March 2009

SUMMARYThe effect of morphactin sprayed at 0, 0·5, 1·0, 1·5 or 2·0 mg/1 on the concentrations of several nutrients in snapdragons (Antirrhinum, majusL.) were studied under glasshouse conditions. Snapdragon plants treated with morphactin increased in K, and Mg but decreased in Ca, Mn, Cu, Fe, and Zn. Action of morphactin and nutrient element relationships are suggested.
An estimate of the energy required for maintenance and live-weight gain by young grazing sheep
Authors: Grimes R. C. 
Published: March 2009

1. The intake of grazing wethers was estimated from the in vitro organic matter digestibility of herbage samples collected from sheep with oesophageal fistulae, and total faecal collections.2. Body water, estimated by isotope dilution, was used to estimate total body energy from estab-lished regressions relating body water to body composition.3. Total body energy was then related to live weight by regression analysis, giving a value of 2044 kcal. per lb. over the range 68-90 lb. empty body weight. From this it was estimated that 2.41 lb. D.O.M. was required per lb. live-weight gain within this range.4. Energy for maintenance was calculated by deducting D.O.M. required for gain from D.O.M. intake. These values were related to live weight by regression analysis to give a value of 1.31 lb. D.O.M./day for the maintenance of a 100 lb. sheep.
The seed productivity of perennial rye-grass varieties
Authors: Roberts H. M. 
Published: March 2009

1. Seed plots of five perennial rye-grass varieties, S23, S24, S321, Melle Pasture and an experimental type, Ba6280, were established in 18 in. rows.2. Each variety was subjected to hard grazing by sheep in September, at ear initiation in spring, and 3 weeks following ear initiation; one series of plots was left ungrazed. Three levels of spring nitrogen, 2, 4 and 6 cwt./acre ‘Nitro-chalk’ (21%N), were applied to subplots.3. S321 produced significantly more seed heads and Ba6280 gave significantly fewer heads than S23, S24 and Melle. September grazing increased head production by 15%, whilst the two spring grazings gave fewer heads than the ungrazed plots. An increase in the rate of nitrogen application in spring favoured head production.
Studies in potato agronomy. I. The effects of variety, seed size and spacing on growth, development and yield
Authors: Bremner P. M. , Taha M. A. 
Published: March 2009

1. Growth and development in relation to yield were studied in the two maincrop varieties King Edward and Majestic in 1959 and 1960. The effects of seed size and spacing were also investigated.2. The total tuber yield, and more particularly the ware yield, of Majestic was greater in both years. This was associated with a longer period of tuber bulking in this variety, due, in 1959, to earlier tuber initiation, and in 1960, to earlier tuber initiation and greater persistence of tuber bulking. Large seed outyielded small seed, although the difference, particularly in ware yield, was relatively small. The seed size effect was associated with a difference in the length of the bulking period, in consequence of a difference in the time of tuber initiation. Total yield tended to increase with decrease in spacing distance; ware yield increased as spacing distance decreased from 24 to 18 in., but there was little difference between 12 and 18 in. spacing. In general, low seed rates performed better than might be expected.
The onset of the breeding season in Southdown ewes in subtropical Australia
Authors: Smith I. D. 
Published: March 2009

Observations on the onset of the breeding season in a flock ofSouthdown ewes in subtropical Australia (latitude 27° S.) indicated that the mean date of onset during the years 1962-65 was 3 March, with annual means ranging from 11 February to 17 March. There was evidence that, under some circumstances, ovarian activity may be initiated before the summer solstice.The onset of the breeding season was later in ewe lambs than in yearling and adult ewes and the mean age at puberty was 239 days.
Factors influencing flower and pod development in oil-seed rape (Brassica napus L.)
Authors: Tayo T. O. , Morgan D. G. 
Published: March 2009

SummaryExperiments were carried out on oil-seed rape, variety Zollerngold, to determine the effects on flower and pod development when (1) the supply of carbon assimilates was reduced by shading or leaf removal at different stages of development or (2) the supply of assimilates to the more apically positioned flowers or pods on the terminal raceme was increased by removing 15 of the most basal flowers or pods.A decrease in the production of carbon assimilates led to fewer flowers and pods developing to maturity and when the stress continued over most of the period of pod development the pods were smaller and had fewer seeds which were also lighter in weight.Removal of the 15 basal flowers or pods led to more of the apically positioned flowers developing into mature pods and the other pods becoming heavier with bigger husks, heavier seeds and sometimes a greater number of seeds.The results of a shading experiment in a controlled environment cabinet suggest that stresses in the supply of carbon assimilates around the time of anthesis are particularly harmful since in addition to reducing the number of pods which develop they appear to restrict the capacity for compensatory growth in the pods that remain when the supply returns to normal.
The growth and development of the beef qualities of Angoni cattle (East African shorthorn zebu). Part II. Linear growth and carcass characters
Authors: Walker C. A. 
Published: March 2009

Part I described the growth of Angoni cattle as shown by changes in live weight. This Part deals with proportional growth as shown by linear growth and carcass characters.LINEAR GROWTHA virtually complete summary of the basic work on linear growth has been given by Brody (1945) and specific references will therefore be quoted only as required for discussion.
X-ray diagnosis of pregnancy in sheep with special reference to the determination of the number of foetuses
Authors: Ardran G. M. , Brown T. H. 
Published: March 2009

1. Sixty-four Dorset Horn ewes and sixty Half- Bred ewes were X-rayed in the pelvic region at stages of pregnancy between 51 and 110 days.2. Diagnosis of pregnancy and estimates of the number of foetuses carried were made from the X-ray film.3. Over the range of gestation stages examined, interpretation of the number of foetuses present was found to be most accurate at stages between 91 and 110 days.4. An accurate estimation of whether the ewe is pregnant or barren can be made from 50 days onwards.
Fertilizer experiments on maincrop potatoes 1955–61
Authors: Boyd D. A. , Dermott W. 
Published: March 2009

Results are given of 124 factorial experiments testing N, P and K fertilizers for maincrop potatoes; the experiments were done by N.A.A.S. Soil Chemists in the years 1955–61. The experimental sites were in sixteen groups, corresponding to particular soil series or complexes.There were substantial differences in mean yield and in response to the lower levels of P and K between soil series; the influence of soil was less at higher rates of application. Alternative methods of soil classification which appeared to be associated with response were texture, experiments on the lighter-textured soils showing higher responses to K; and depth of freely drained soil, soils with impeded drainage being associated with larger P responses. Responses to P and K were particularly large on soils in Wales and N.W. Cumberland.
Results from experiments on winter barley measuring the effects of amount and timing of nitrogen and some other factors on the yield and nitrogen content of the grain
Authors: Penny A. , Widdowson F. V. , Jenkyn J. F. 
Published: March 2009

SummarySeven experiments on winter barley, made during 1979–81, measured the effects of several amounts of nitrogen, applied at different times in spring, on grain yield and nitrogen content. All of these experiments also tested a growth regulator applied in spring, and five of them tested fungicide sprays. In 1980 the experiment at Rothamsted also tested sowing dates, and an eighth experiment, also at Rothamsted in 1980, tested sowing dates and mildew fungicides applied in autumn or spring. In all the experiments treatments were tested in factorial combination.N applied in February was less effective than N applied in March and both were less effective, in terms of grain yield, than N applied in April. Divided dressings were best applied in February and April or March and April; effects on % N in grain followed the same pattern and so, therefore, did the efficiency of uptake of fertilizer N. The growth regulator consistently reduced the length of the straw and diminished lodging; it increased yields in five of the seven experiments in which it was tested.Responses to fungicides were inconsistent from year to year. Sowing in September rather than in October 1979 increased yield in both of the experiments at Rothamsted in 1980, especially of the 6-row variety Hoppel.
Food intake in sheep following intraruminal infusion of extracts from lucerne silage with particular reference to organic acids and products of protein degradation
Authors: Buchanan-Smith J. G. , Phillip L. E. 
Published: March 2009

SummarySheep were infused intraruminally with iso-osmotic solutions of saline, organic acids or lucerne silage extracts with or without additional acids and products of protein degradation found in silage. The post-ingestive effects of silage constituents on food intake were assessed by measuring the voluntary consumption of high dry matter silage over a 20 h period following feeding. In Expt 1, three different silage extracts each depressed food intake up to 4 h following feeding. In Expt 2, one of these extracts, to which 40 g of γ-amino butyric acid (GABA) was added, depressed intake up to 4 h following feeding; with the further addition cf 10 g α-amino butyric acid (AABA) and 28 g amines to this extract, intake was enhanced within 0·5 h but depressed from 4 to 8 h following feeding. In Expt 3, infusion of organic acids alone did not significantly depress food intake relative to saline, nor was there a discernible effect on food intake when graded levels of nitrogenous constituents from silage were added to the infusates. In Expt 4, infusion of an extract, to which only AABA and four other amines were added, depressed cumulative intake up to 8 h following feeding and had a more pronounced effect on food consumption than infusion of the extract with these constituents together with GABA. It was concluded that soluble constituents in silage can inhibit intake but no single constituent is primarily responsible.
Male sterility in field beans (Vicia faba L.). IV. Use of cytoplasmic male sterility in the production of F1 hybrids, and their performance in trials
Authors: Bond D. A. , Fyfe J. L. , Toynbee-Clarke Gillian 
Published: March 2009

1. A method of producing hybrid beans with the aid of a cytoplasmic male-sterile is described.2. Most of the requirements of large scale production of hybrid seed can be met: use of genetic markers showed that the male sterility allowed 100% cross fertilization; there was no evidence of a deficiency of insect pollinators near Cambridge; and fertility restoring lines are available.3. The importance of being able to maintain a high level of sterility in the female parent line is emphasized. Methods of improving the proportion of sterile plants in the sterile phase of an inbred are discussed. The tolerable level of fertility in progenies of sterile parents depends on the level of sterility necessary in the female parent of the final cross. Five inbreds are being handled with less than 2% of fertile plants in their sterile phase.
Relationships between organic-matter digestibility, dry-matter intake and solute mean retention times in sheep given a ground and pelleted diet
Authors: Faichney G. J. , Gherardi S. G. 
Published: March 2009

SUMMARYThe relationships between organic-matter digestibility (OMD), dry-matter intake (DMI) and the mean retention time (MRT) of unabsorbed solutes in the gastrointestinal tract were examined using six fistulated, cross-bred, castrate male sheep. Measurements were made on each sheep at two different DMIs within the range 28–81 g D.m./(day. kg0·75). There were negative, curvilinear relationships between MRTs (both rumen and total) and DMI and positive, curvilinear relationships between OMD and MRTs. As a consequence, there was a negative, rectilinear relationship between OMD and DMI. OMD declined by 0·022 when DMI increased from calculated maintenance to twice maintenance. The proportion of the total MRT accounted for by rumen MRT did not change significantly; the mean value was 0·364 ( ± S.e. 0·010).
Exploiting the pasture capacitance probe in agricultural research: a comparison with other methods of measuring herbage mass
Authors: Crosbie S. F. , Smallfield B. M. , Hawker H. , Floate M. J. S. , Keoghan J. M. , Enright P. D. , Abernethy R. J. 
Published: March 2009

SummaryThe precision of the capacitance probe in detecting herbage mass differences between treatments has been assessed on a cross section of field trials in Otago-Southland, New Zealand. Used thoughtfully, the probe appears at least as good as any other alternative. Corrected meter readings from the probe may be used directly for relative ranking of treatments although calibration is desirable for interpretation purposes, and becomes essential when swards of widely differing composition are to be related. Considerable overall time savings, especially in the laboratory, are possible in comparison with other methods.
Influence of cotton-seed meal and barley grain supplements on intake, digestion, live-weight gain and wool growth in sheep fed NaOH-treated oat and wheat straw diets
Authors: Amaning-Kwarteng K. , Kellaway R. C. 
Published: March 2009

SummaryGrowth and digestibility trials were conducted to investigate responses of young cross-bred sheep to alkali-treated straws and supplements. Oat and wheat straws were coarsely milled, sprayed with NaOH solution and then sprayed with a solution containing N, S, P, Cu and Co, and mixed with powdered limestone. The treated straws were fedad libitumwith no supplement (0) or with 150 g/day of either cotton-seed meal (CSM) or whole barley grain (B). In a preliminary trial to study the effect of frequency of ort collection on intake of treated straw, consumption decreased (P< 0·05) when frequency of ort collection was reduced from once daily to once weekly. This was associated with an increase in the neutral detergent fibre content of the orts. During the growth trial, which lasted 105 days, intake of treated straw increased by 34%.When no supplement was fed, digestibility of treated oat straw was higher (P < 0·05) and dry-matter intake lower (P< 0·05) than that of treated wheat straw. However, calculated intakes of metabolizable energy (ME) and measurements of growth and wool production were similar on the two straws (P> 0·05).When supplements were fed, there was no effect on intake of the treated straws. Mean live-weight gains were 51·4, 80·2 and 77·3 g/day on treatments 0, CSM and B respectively (P< 0·01). This was associated with higher intakes of ME (P< 0·01) which accounted for 73% of the variation in live-weight gains. Mean clean wool growth was 7·6, 10·5 and 9·3 g/day on treatments 0, CSM and B respectively (P< 0·01). This effect was associated more with nitrogen (N) absorption than with ME intake (80 and 48% of the variation in wool growth respectively).It was concluded that the treated straws provided sufficient nutrients for modest growth in young sheep, that the supplements had no effect on intake of the treated straws and that additional live-weight gain and wool growth obtained by feeding CSM and B were associated with energy intake and nitrogen absorbed respectively.
Studies on Awassi sheep in Lebanon:I. Production traits of a flock
Authors: Rottensten Knud , Ampy Franklin 
Published: March 2009

SUMMARY1. The Awassi ewes reached an average live weight of 45 kg at two years of age and a mature weight of 57 kg at four years of age.2. The average yearly production of grease wool has been 2·2 kg.3. When rams were kept with the flock throughout the year approximately 60% of the lambings occurred during January–February. It declined rapidly during the following months and no lambs were born in July–August.4. Single lambs had an average birth weight of 4·6 kg for males and 4·3 for females. Twin lambs were about 20% lighter than singles. The corresponding weaning weight at two months of age was 17·9 and 16·8 for singles and 13·4 and 12·4 for twins.5. The twinning rate increased from 5% at first lambing to 30–35% at 6th lambing, when the ewes were about seven years old.
The relationship between rumination and the amount of roughage eaten by sheep
Authors: Gordon J. G. 
Published: March 2009

1. The jaw movements of four sheep were recorded while they were consuming a daily diet consisting of a constant concentrate allowance along with a hay intake varying from 25 or 50 g. daily by daily differences of 25 or 50 g. up to maximum voluntary intake.2. Rumination increased with hay intake in a characteristic way. The actual time devoted to chewing when plotted against hay intake produced a curve consisting of a rapid rise, a fairly level part, a further gradual rise and a final levelling-off. This was less clear when the total rumination time or the total number of regurgitations were compared to the hay eaten.
The oxygen requirement of crop roots and soils under near field conditions
Authors: Brown N. J. , Fountaine E. R. , Holden M. R. 
Published: March 2009

1. Agricultural crops can be grown to maturity with their root systems and associated soil sealed into 1680 1. respirometers. The crops appeared to grow normally and produced the expected agricultural yields.2. The mean daily oxygen consumption at maturity of the roots of the following crops grown at normal agricultural spacings were: potatoes 2·8 l./m2, marrowstem kale 5·6 l./m2 and tobacco 3·0 l./m2.
A comparison of the deep-body temperature of Hereford and zebu cows recorded continuously by radio-telemetry under similar field conditions
Authors: Bligh J. , Lampkin G. H. 
Published: March 2009

1. A radio-telemetric system linked to a thermistor- probe embedded in deep muscular tissue has been used to record continuously variations in deep-body temperature during 46–66 hr. in three Hereford (temperate) and three East African zebu (tropical) cows under similar temperate field conditions.2. The limitations of the ‘probe’ technique for measuring deep-body temperature are discussed.
The use of ‘worm-free’ sheep in grazing experiments
Authors: Spedding C. R. W. , Large R. V. , Brown T. H. , Wilson I. A. N. 
Published: March 2009

1. It has proved possible to operate a ‘worm-free’ area in which sheep grazing experiments can be carried out, without significant interference from disease.2. The organization of such a unit is described and the results are presented in terms of the problems and difficulties which have been encountered during 4 years of continuous and increasing use. There is no apparent reason why these problems should increase with time.
Effect of urea and ammonium sulphate applied before sowing on sudangrass seedlings
Authors: Worker G. F. 
Published: March 2009

SUMMARYStudies were conducted to determine possible leaching or fixation problems in growing sudangrass (Sorghum Sudanese Stapf.) when urea, ammonium sulphate plus triple superphosphate, and ammonium polyphosphate fertilizer were applied as a seed-bed application to the very sandy soils of the Libyan Sahara near the Kufra Oasis. The effectiveness of the nitrogen source was measured by plant colour, leaf analysis, and seedling height.The urea nitrogen plus single superphosphate when applied and watered-in did not supply enough nitrogen to obtain a vigorous green seedling compared with ammonium polyphosphate (21% N, 53% P 2O6), which produced excellent vigorous green seedlings. The ammonia source supplied more nitrogen than the urea imder the conditions of these trials.The application of urea 1, 2, 4, and 8 days before sowing was inadequate in supplying nitrogen to meet the early demand of the sudangrass seedlings. Sudangrass seedlings after 26 days were only 5–6·3 cm tall. With a seed-bed application of 36–72 kg N/ha as ammonium sulphate under comparable circumstances, sudangrass seedling height was 21·7 cm. The plants receiving no nitrogen applied before sowing were 6·7 cm high, similar to those which received urea.Under these virgin sandy soil conditions, the ammonium sulphate and ammonium polyphosphate (21% N, 53% P2O5) fertilizers applied to the seed bed were retained within the root zone in sufficient amounts to give a vigorous, non-deficient sudangrass seedling. Nitrogen from urea was deficientand presumed leached beyond reach of the seedling root when applied to the seed bed. Applied post-emergence, however, urea was a very satisfactory source of nitrogen.