bluuebunny/crossref_metadata_2025 huggingface dataset:
Results from three cycles of six-course rotations on light land
Authors: Hanley F. , Ridgman W. J.
Published: March 2009

A rotation experiment comparing the effects of length, type and management of leys on three test crops in six-course rotations during three cycles is described and the results discussed.

Although the yields of the test crops varied from cycle to cycle there were no clear-out trends to suggest that the yield improves or deteriorates as time goes on with these particular rotations; the full benefit of the leys was obtained in the first cycle.

The yield of potatoes immediately following the leys was no greater than the yield in an all-arable rotation receiving adequate nitrogen fertilizer, but the yields of two, barley crops following the potatoes were less in the all-arable rotation than in ley rotations even when 58 kg N/ha/year and 38t dung/ha/cycle had been applied and trefoil ploughed-in in the all-arable rotation. Rotations containing lucerne or lucernecocksfoot leys gave their greatest yields of potatoes and of barley following potatoes without any applied nitrogen fertilizer, but in the second barley crop showed the same sort of nitrogen responses as the all-arable rotation.

Yield data were also obtained on the leys themselves in each cycle. These showed a decline from the first to third cycle in yield of broad red clover grown as 1-year leys and in that of 3-year leys which contained lucerne, both of which could be explained by the build-up of specific diseases. There were also changes in the effect of grazing compared with mowing on the yield of some leys but little change in the effects on leys of applying nitrogen to them. However there was no suggestion that these changes affected the arable crops that followed.
The growth and development of the alimentary tract in Asiatic swamp buffalo and zebu cattle
Authors: Moran J. B. , Wood J. T.
Published: March 2009

The weights of components of the alimentary tract were recorded in 55 swamp buffaloes and 51 zebu cattle slaughtered at Bogor in West Java. These were related to hot carcass weight (HCW) and slaughter live weight (SLW), the latter being calculated from locally developed regressions relating live weight to chest girth. Huxley's (1932) allometric equation was used in its logarithmic form as the basis for covariance analyses of the data. A stepwise regression analysis was also undertaken using a linear model relating HCW and gut component weight to species, sex, age and slaughter condition with SLW as the independent variable.

There were significant differences in dressing percentage between buffaloes (38·1 %) and zebus (44·8%) at 340 kg SLW and these were due to species differences in full gut weight rather than weights of other non-carcass components. The allometric growth coefficients for total gut, or gut component, were generally higher in buffaloes than zebus, but the differences were not statistically significant. Together with other published data, these observations suggest that the gut contents may contribute more to the increase in live weight of buffaloes than in zebus.

At the same SLW or HCW, the buffaloes had the heavier weights of full and empty total gut, full and empty reticulo-rumen and total gut contents. At the same total empty gut weight, buffaloes had the heavier empty reticulo-rumen. It was suggested that Indonesian swamp buffaloes and zebu cattle fed on village-type low-quality diets may also differ in the rate of development of their alimentary tract and this could have implications for their comparative nutritional physiology.
Adjustment for competition between varieties in plant breeding trials
Authors: Kempton R. A.
Published: March 2009

A method is proposed for correcting for competition effects in yield trials by joint regression of plot yields on to the yields of neighbours. Estimation of the variety effects and competition coefficient along with tests of significance are described for a sugar-beet trial with single-row plots where competition effects are assumed to extend only to plants in immediately adjacent rows. For designs which are balanced for neighbouring varieties it is feasible to estimate separate varietal competition coefficients which may be partitioned into components for sensitivity and aggressiveness. An example is given of this extended model fitted to a competition diallel of seven species. While species differed in their sensitivity to competition there was no essential difference between inter- and intra-species behaviour. The model is used to assess comparative varietal performance in monocultures from performance in small plot trials.

(Note that the general term ‘variety’ is used throughout this paper to refer to progenies at any stage in a selection programme.)
The effects of the growth-regulating compounds methyl decanoate and 2, 3, 5-triiodobenzoic acid on potato tuber size
Authors: Wurr D. C. E.
Published: March 2009

Application of methyl decanoate to a potato crop about the time of tuber initiation reduced the total yield and the yield of tubers in the grade 2·5–5·5 cm though neither of these reductions were significant. However, application of 2,3,5-triiodobenzoic acid increased the yield of tubers 2·5–5·5 cm by up to 20% while having no significant effect on total tuber yield. This change in the tuber size distribution was due to a more even partition of photosynthate between tubers and not to an increase in the total number of tubers.
Equations to predict the leaching of nitrate uniformly incorporated to a known depth or uniformly distributed throughout a soil profile
Authors: Burns I. G.
Published: March 2009

Equations to predict the leaching of nitrate either uniformly incorporated to a known depth or uniformly distributed in field soils can be reduced to the approximate form:

where f is the fraction of nitrate leached below h cm in a soil of field capacity Vm (% by volume) after P cm of drainage has passed through the profile. If nitrate is initially incorporated uniformly to a depth of w cm, then x = h – ½w(where h ≥ w); if nitrate is distributed uniformly throughout the whole profile, then x = ½h. For surface-applied nitrate x = h (Burns, 1975).

Observed mean displacements in published experiments have been compared with predictions from the equations and from equations in which the mean movement of nitrate and water are assumed equal. The new equations give better agreement with the observed data.
Selection for seedling vigour in Festuca arundinacea
Authors: Faulkner J. S. , Johnston Fiona , McAneney D. M. P.
Published: March 2009

Two sets of experiments were carried out to compare methods of selecting Festuca arundinacea (tall fescue) for improved seedling vigour.

In the first, germination and seedling growth of four varieties (Goar, Lironde, S. 170, and ZW 42–6) were compared in hydroponic growth tanks. From each variety, groups of seedlings were selected for each of four vigour characters (speed of germination, leaf length, root length and speed of production of the second leaf) and a fifth group was selected at random as a control. Plants of each group were intercrossed in isolation and their progeny compared.

In the second, S. 170 was studied through two cycles of selection in a soil-based compost. In the first cycle, groups of seedlings were selected for each of five characters (speed of emergence, leaf length, and speed of production of the second leaf, first axillary tiller and coleoptile tiller). Two further groups were selected randomly. In the second cycle, the progeny of each group were reselected for the same character as their parents. Both first- and second-cycle progeny were compared among themselves.

Significant direct responses to selection were obtained in all characters except speed of germination in hydroponics. Indirect responses also occurred but were mostly smaller and in response to selection for a related character, e.g. selection for early tillering resulted in early second leaves and vice versa. Two cycles of selection raised the frequency of coleoptile tillers from about 5 to 55 %, but the concomitant advances in vigour characters were smaller than those achieved by direct selection. It is argued that for practical purposes the basic criterion in selecting for improved seedling vigour should be rapid attainment of a particular growth stage such as appearance of the first tiller. Since speed of emergence itself responded to selection, the attainment of such a stage should be related to date of sowing rather than of emergence or germination.

In the progeny of the hydroponic selections, all characters showed significant varietal differences, some of them the reverse of differences between the parent populations of the varieties. These results illustrated the importance of seed provenance as a determinant of seedling vigour, and suggest that choice of parent material is important in breeding for improved vigour.
Some effects of chloral hydrate on rumen fermentation and digestion in sheep
Authors: Mathers J. C. , Miller E. L.
Published: March 2009

Two experiments were carried out with adult sheep to investigate the effects of chloral hydrate (CH) on rumen metabolism and on the sites and extent of digestion.

Experiment 1 confirmed that CH is a very potent methane inhibitor; doses of 1 or 4 g/day reduced methane production to 4% of that observed in the absence of the drug. In both experiments, CH administration altered the proportions of volatile fatty acids in rumen fluid. The main changes were an increase in propionic acid and a decrease in acetic acid with smaller increases in the proportion of isovaleric, valeric and caproic acids. Stoichiometric calculations indicated that only 21% of the hydrogen saved by prevention of methanogenesis was diverted to the synthesis of additional propionic and butyric acids and the fate of the remaining hydrogen was not determined unequivocally.

CH had little effect on the extent of biohydrogenation in the rumen of the long-chain fatty acids in dried grass.

The apparent digestibility of ether extract was reduced (P< 0·05) by CH but those of other proximate constituents and energy were little affected. There were no s gnificant effects of CH on the extent of digestion of dry matter, organic matter, non-ammonia nitrogen or ash between the mouth and abomasum, abomasum and terminal ileum or ileum and anus.
A note on sampling technique for winter oil-seed rape (Brassica napus L.)
Authors: Scarisbrick D. H. , Clewer A. , Daniels R. W.
Published: March 2009

The response of three spring cultivars of oilseed rape to five levels of nitrogen fertilizer (0 to 200 kg/ha) was studied during 1978–9 (Scarisbrick, Daniels & Alcock, 1981). Sampling problems, practical difficulties of measuring yield components, and the high co-efficients of variation for these data were discussed. During the course of further investigations on the winter cultivar Jet Neuf (established on approximately 75000 ha in the U. K. during 1980–1) within-plot variability for plant weight was assessed in order to indicate the size of sample necessary to compare treatment means.
Lodging studies inLolium perennegrown for seed: 1. Seed yield and seed yield components
Authors: Hebblethwaite P. D. , Burbidge A. , Wright D.
Published: March 2009

The effects of lodging on the seed yield of S. 23 and S. 24 perennial ryegrass were investigated in a series of field experiments from 1973 to 1976. Natural lodging severely reduced seed yield in all years as a result of a decrease in the number of seeds per unit area. Controlled lodging at different stages of crop growth produced more variable results, indicating that lodging may affect both pollination and seed development. Disturbance of the crop during anthesis in order to aid pollination did not improve seed yields, possibly as a result of damage incurred.
Some effects of potassium chlorate administration onin vitroandin vivorumen fermentation
Authors: Barry T. N. , Harte F. J. , Perry B. N. , Armstrong D. G.
Published: March 2009

Hay was fed to anin vitrocontinuous culture of the rumen microbial population and to sheep kept in metabolism cages, and the effects of potassium chlorate addition on the rumen fermentation were studied. The compound was given for 8 daysin vitroand for either 3 or 8 daysin vivo.

Potassium chlorate additionin vitro(13·7 mg/g hay D.M.) depressed the production of CH4and acetate, had little effect on propionate production and caused a small increase in the production ofn-butyrate andn-valerate. The treatment also depressed cellulose digestion and the concentration of DNA in fermentor liquor, but increased the CO2:CH4ratio in fermentor gas.

When givenin vivofor 8 days at 6·7 mg/g hay D.M., potassium chlorate progressively depressed total VFA concentration in rumen fluid, had no effect on VFA molar proportions but caused a small increase in the CO2:CH4ratio in rumen gas. When administeredin vivofor 3 days at 14·4–15·3 mg/g hay D.M. the treatment increased the molar proportions of propionate and depressed those of acetate in rumen fluid without affecting total VFA concentration. There were considerable differences between animals in propionate response, and the maximum responses were generally obtained 2–5 days after dosing had ceased. Potassium chlorate addition also caused a temporary reduction in appetite with some sheep.

It was concluded that potassium chlorate was toxic to the rumen microbial population when given for 8 days, but that large doses given over 3 days could be used to increase the ratio of propionic acid relative to acetic and butyric acids produced from the rumen fermentation.
The effects of moisture, propionic acid, sodium hydroxide and anaerobiasis on the stability of vitamin E in stored barley
Authors: Rice D. A. , Blanchflower W. J. , McMurray C. H.
Published: March 2009

Two experiments were designed to measure the effect of current barley storage systems on vitamin E stability.

Whereas propionic acid and sodium hydroxide treatment of moist barley results in destruction of vitamin E, neither moisture per se nor anaerobic storage has such a detrimental effect. The destruction is most severe and rapid with alkali treatment, the reaction having substantially reached completion by 5 days. All the vitamin E isomers were affected to varying degrees, the order of susceptibility to decay being α-tocopherol > γ-tocopherol > α-tocotrienol > γ-tocotrienol.

Possible explanations are given as to why the findings incriminating propionic acid in vitamin E destruction are at variance with currently held opinion.
The effect of variation in phosphorus intake on salivary phosphorus secretion, net intestinal phosphorus absorption and faecal endogenous phosphorus excretion in sheep
Authors: Scott D. , Whitelaw F. G. , Buchan W. , Bruce L. A.
Published: March 2009

Mature sheep fitted with rumen and duodenal cannulae, and fed a pelleted hay diet, were given supplementary phosphorus by continuous infusion into the rumen and the effects on salivary phosphorus secretion, net intestinal phosphorus absorption and faecal endogenous phosphorus excretion were studied. In control periods little phosphorus was excreted in the urine and little increase was seen in response to supplementation, the faeces being the major pathway for excretion. Increasing phosphorus intake led to an increase in net intestinal phosphorus absorption, a rise in plasma phosphate concentration, an increase in salivary phosphorus secretion and an increase in faecal endogenous phosphorus excretion. Overall net intestinal absorptive efficiency for phosphorus did, however, decrease as intake rose so that changes in faecal endogenous phosphorus excretion were in part due to increased salivary phosphorus secretion and in part to a reduction in overall absorptive efficiency. The significance of these changes in relation to the control of phosphorus balance in ruminants is discussed.
Number of kernels in wheat crops and the influence of solar radiation and temperature
Authors: Fischer R. A.
Published: March 2009

The number of kernels per m2 (K) in well managed and watered wheat crops was studied using results of experiments in Mexico and Australia in which short spring wheat cultivars were subjected to independent variation in radiation, largely via artificial shading, and in temperature. Also crops subjected to differences in weather (year), sowing date and location within Mexico, revealed responses to the natural and simultaneous variation which occurs in radiation and temperature. Responses in K were interpreted in terms of spike dry weight at anthesis (g/m2) and number of kernels per unit of spike weight.

K was linearly and most closely related to incident solar radiation in the 30 days or so preceding anthesis, herein termed the spike growth period; for the cultivar Yecora 70 with full ground cover the slope was 19 kernels/MJ. This response seemed largely due to a linear response of crop growth rate to intercepted solar radiation. The proportion of dry weight increase partitioned to the spike increased somewhat with reduced radiation. Also increasing temperature in the range 14–22 °C during this period reduced K (slope approximately 4% per CC at 15 °C). The cause appeared to be lower spike dry weight due to accelerated development. The number of kernels per unit spike weight at anthesis was little affected by radiation or temperature, and averaged 78±2/g for the cultivar Yecora 70.

With natural variation in radiation and temperature, K was closely and linearly correlated with the ratio of mean daily incident or intercepted radiation to mean temperature above 4·5 °C in the 30 days preceding anthesis. As this ratio, termed the photothermal quotient, increased from 0·5 to 2·0 MJ/m2/day/degree, K increased from 70 to 196 × 102/m2. These responses of K to weather, sowing date and location were closely associated with variation in spike dry weight.

It was concluded that the ratio of solar radiation to temperature could be very useful for estimating K in wheat crop models. Also the analysis of K determination in terms of spike dry weight appeared promising, and suggests that wheat physiologists should place greater emphasis on the growth period immediately before anthesis.
Characterization of climatic factors affecting chilling injury in field-grown ratoon cotton
Authors: Sachs M. H. , Zilkah S.
Published: March 2009

text abstract

The response of cotton (Gossypium hirsutum L.) to chilling temperatures has been documented mainly for germinating seeds and young seedlings (Christiansen, 1963; Christiansen & St John, 1981; Guinn, 1971; Sellschop & Salmon, 1928). Ratoon (known also as stub or biennial) cotton offers an opportunity to study the chilling injury of mature plants under field conditions. Observations showed that ratooning plants suffer stand loss during the winter. However, the surviving plants recover and start growing vigorously when temperatures rise, early in the following spring (Ellern, 1966; Evenson, 1970; McClintic, 1981).
The availability of copper to grazing ruminants in parts of North Yorkshire
Authors: Givens D. I. , Hopkins J. R.
Published: March 2009

A total of 225 herbage samples were taken from two areas with a history of bovine hypocupraemia and examined for their Cu, Mo, total S, Zn, Fe and Cd content.

In general, the concentrations of Cu and Mo (mean values 10·4 and 1·6 mg/kgD.M. respectively) were normal, as were those of Zn, Fe and Cd (mean values 43, 255 and 0–59 mg/kg D.M. respectively). The total S concentrations (mean value 3·5 g/kg D.M.) were, however, higher than found by some other workers.

The concentrations of available herbage Cu were calculated using the following relationship of Suttle & McLauchlan (1976):

logTA Cu = –0·0019 Mo–0·0755 S–0·0131 Mo × S–1·153,

where TA Cu is the true availability of Cu, and Mo and total sulphur (S) are dietary concentrations as mg/kg D.M. and g/kg D.M. respectively. Animal requirements for available Cu were derived from estimates of the factorial Cu requirements of various classes of livestock, and when these were compared with the calculated concentrations of available Cu in the herbage they provided a possible explanation for the widespread hypocupraemia experienced in these areas.
Storage stability of DDT/Lindane emulsifiable concentrates and reworking deteriorated stocks
Authors: El Attal Z. M. , Moustafa Omayma K. , Said A. A. A.
Published: March 2009

Investigations of the reasons for the instability of emulsifiable concentrates (ECs) during storage and a study of reprocessing insecticide ECMs whose emulsification propertieshad deteriorated during storage is reported. Bioassay showed that very stable emulsions, although physically perfect, leave inadequate residues on the treated leaves. When a deteriorated EC was reprocessed, its emulsification properties were restored, resulting in better adherence of the insecticides on the leaves' surfaces; the residual toxicity was increased.
Effect of mulching and kaolin foliar spray on mung (Vigna radiata) – rapeseed (Brassica campestris) double cropping system under rainfed conditions
Authors: de Rajat , Giri Gajendra
Published: March 2009

Results are described of an experiment made at the Indian Agricultural Research Institute, New Delhi, for 4 years under semi-arid seasonally dry tropical conditions to explore the possibilities of double cropping in the traditionally monocropped areas. Use of straw mulch did not increase mung yield in the monsoon season with welldistributed rainfall but increased its yield in a year when the monsoon receded early. Irrespective of rainfall pattern, mulching helped conserve enough moisture in the top 30 cm of soil to enable germination and quick establishment of the rapeseed crop. Mulching continued in the rapeseed crop conserved soil moisture until the flowering stage and increased the yield of rapeseed by 23%. Kaolin, a reflectant material applied at the preflowering stage, also increased seed yield of rapeseed.
Number of fibres in the skeletal muscle of miniature pigs
Authors: Stickland N. C. , Goldspink G.
Published: March 2009

There is evidence that selection for small body size in mice results in a decrease in the total number of muscle fibres in a given muscle (Luff & Goldspink, 1967; Hanrahan, Hooper & McCarthy, 1973). It has also been shown that small chickens have fewer muscle fibres in certain muscles than larger chickens (Smith, 1963). This type of work has not, however, been extended to a study of the larger domestic animals. At Göttingen in Germany, Haring et al. (1966) have developed a breed of miniature pig which, at 6 months of age, was about a third of the body weight of commercial pigs. We therefore decided to investigate the muscles of these miniature pigs and compare them with commercial pig muscles, paying particular attention to the number of muscle fibres.
The storage of ware potatoes in permanent buildings I. Storage in bins in an uninsulated store, 1946–7
Authors: Wager H. G. , Burton W. G. , Mann G.
Published: March 2009

Permanent buildings of a variety of designs have been in widespread use for many years as potato stores on the Continent of Europe and in the United States of America. (For a summary of recent literature, with references, see Rose & Cook, 1949.) There are examples of buildings being used as potato stores in this country (e.g. Keith, 1941), but the bulk of the crop is stored in clamps. Because the climates of the U.S.A. and the Continent of Europe differ markedly from that of Great Britain, it is not possible to use the types of store developed in those regions as models for British stores. Over much North America and the Continent of Europe the stores are designed to withstand severe winter frosts, and the main problem is to keep the temperature of the tubers high enough to prevent freezing, the metabolic heat being readily removed if necessary by a small amount of controlled ventilation. Under British conditions the mean daily temperature for most of the storage season, above the optimum for potato storage (40·42° F.), and therefore the main problem is that of keeping the tubers cool. This could, of course, be achieved by using a cold store, but cold storage is considered too expensive. To design a store, information is required about the temperatures attained by stacks of potatoes at different times of the year, the effectiveness ventilation in controlling the temperature, the relation of temperature in different parts of the stack to dimensions of the stack, and to the insulation both of the bin and of the building. To obtain this data a programme of work was initiated, and the results of the first year's work in a building of very low insulating capacity are described in this paper. The climatic conditions during this year, i.e. 1946–7, were very abnormal, a very cold winter followed by a hot spell in the spring which provided an abnormally severe test of an uninsulated store. Later papers will consider storage in an insulated building with adequate ventilation.
Regrowth characteristics of an S. 23 perennial ryegrass sward defoliated at early stages of reproductive development
Authors: Davies Ieuan
Published: March 2009

Patterns of stem development in late spring/summer regrowths after initial cuts at three growth stages are described. The stages at which the initial cuts were taken were: (a) before stem apices were raised to defoliation level (5 cm), (b) two weeks later when the apices of about 90% of the stem tillers were raised above this height, and (c) four weeks after (a), when the apices of all stem tillers were raised well above cutting height.

Following an initial cut at stage (a) stem development was quickly resumed, the most advanced tillers being devoid of leaf blades. After initial cuts at the later stages there was virtually no stem development until after the fourth week of regrowth.

The greater proportion of stem tillers in the earlier regrowth was not reflected in reduced digestibility during the first six weeks from cutting.

Reproductive (apical) development was generally weak in tillers in which stems developed in midsummer (after cutting at stages b and c); at least two-thirds of these tillers were indeterminate.

The significance of the distinct batch of stem tillers developing in spring is discussed, and the data are also considered in relation to (i) avoiding stemmy regrowths in spring, (ii) stem development and herbage quality, and (iii) summer stem extension and the perennation of the sward.
The effect of quality and quantity of carbohydrate and protein in the ration of the sheep on the digestibility of cellulose and other constituents of the ration, with a note on the effect of adding vitamins of the B-complex on the digestibility and retention of the nutrients of a hay ration
Authors: Head M. J.
Published: March 2009

1. The effects of various starch and protein supplements on the digestibility of cellulose determined by the Norman-Jenkins technique and other constituents of the ration were studied in sheep.

2. The addition of small amounts of maize or potato starch or flaked maize to a ration of about 1 lb. of poor hay was associated with a depression in the digestibility of (Norman-Jenkins) cellulose.

3. When tested separately at varying levels, the addition of nearly pure maize protein, casein, white fishmeal, decorticated groundnut cake meal, urea or urea + DL-methionine, had no effect on the digestibility of cellulose, at any particular level of starch equivalent.

4. The digestibility of nitrogenous nutrients was depressed by the addition of maize starch or flaked maize to the ration except when urea was the nitrogen supplement. The depression was even greater when potato starch was added to the ration instead of maize starch.

5. The retention of nitrogen was not decreased by the addition of starch to the ration, although the digestibility of nitrogen-containing material was depressed. The retention was increased when starch was added to a ration containing casein.

6. The retention of nitrogen was poor from rations containing urea and starch, but it was slightly improved by the supplementation with 1 g. DL-methionine per day.

7. The addition of the various supplements had no marked effect on the digestibility of the dry matter or ‘other nutrients’ of the ration.

8. It is suggested that the growth of the microorganisms digesting cellulose in the rumen is not dependent on the supplementary feed nitrogen when the substrate they are digesting contains a reasonable amount of nitrogen. This amount appears to be about 1%.

9. The addition of vitamins of the B-complex to a daily ration of 1100 g. of hay did not affect the digestibility of the dry matter or nitrogencontaining substances or the retention of nitrogen by sheep.
The relationship in acid soils between base saturation and phosphorus uptake by grasses
Authors: Birch H. F.
Published: March 2009

Analyses of grass samples from seventeen fertilizer trials on acid soil showed that both the percentage phosphate in the grass and the amount of phosphate removed by the crop were significantly and directly related to the percentage saturation of the b.e.c. of the soil. The amount of acid-soluble phosphate by difference (Table 1, A — B) was also significantly and directly related to the percentage phosphate in the grass but not to the amount taken up by the crop. The amounts of exchangeable bases, exchangeable calcium and acid-soluble, adsorbed and watersoluble forms of phosphate showed no significant relationships with phosphate uptake and percentage phosphate in the grass.

The percentage saturation of the b.e.c. was found to be, on the average, about five times as effective a contributory factor to the percentage phosphate in the grass as the amount of acid-soluble phosphate by difference. The results confirm previous work, which indicated that in acid soils the main form of available phosphate is that associated with the exchangeable bases the effective presence of which is governed by the percentage saturation of the b.e.c. It is considered that phosphate availability and response in acid soils are best assessed by considering the percentage saturation of the b.e.c. rather than the amounts of some form or forms of phosphate in the soil.

The grass analyses also showed that when the amount of phosphorus (P) hi the dry grass exceeds 0·33% no response to phosphate is to be expected. When the percentage in the grass is less than 0·23% responses of 10% or more are likely.
Methods of applying fertilizers for herbage crops
Authors: Cooke G. W. , Widdowson F. V.
Published: March 2009

Phosphate-potash fertilizer was drilled in bands 20 in. apart and 3 in. below the soil surface and compared with similar dressings broadcast on the surface for established crops of sainfoin. On unmanured plots yields were not reduced by cutting grooves for the fertilizer bands. Broadcasting fertilizer on the surface produced consistently more sainfoin hay than dressings placed in bands. In similar experiments on permanent grass broadcast fertilizer also gave consistently more hay than bands of fertilizer placed 10 in.apart. Intheabsence of fertilizer small decreases in yields of grass were caused by cutting grooves. The advantages of an equal supply of nutrients to all the plants in an established sward, obtained by broadcasting fertilizers, outweighs any disadvantage from confining the application to the soil surface.

Two experiments on lucerne in 1950–51 compared broadcast dressings of phosphate-potash fertilizer harrowed into the seed-bed with the same quantities of fertilizer placed in one band 2 in. to the side of the seed. Side-band placement did not give better early growth than broadcasting. Broadcast fertilizer gave higher yields of hay than placed fertilizer at one centre in the first year. There were no significant differences at either centre between yields of hay given by broadcast and placed fertilizer in the second year. When the dressings were divided, half being applied at sowing-time and the remainder in the spring of the following year, slightly lower yields were obtained than from dressings applied wholly at sowing.

A further experiment on lucerne was laid down in spring 1952. Superphosphate, muriate of potash and a mixture of the two fertilizers were compared both when broadcast and ploughed in and when broadcast on the seed-bed. All the dressings of broadcast fertilizer were tested in the presence and absence of a ‘starter-dose’ of superphosphate drilled directly beneath the seed. The ‘starter-dose’ gave much better early growth and higher yields of lucerne than any of the dressings of broadcast phosphate and potash. Broadcast fertilizer ploughed in tended to give higher yields at the first cutting than seedbed dressings. At the second cutting there was little difference between yields given by ploughed-in dressings and dressings broadcast on the seed-bed.

There is no case for introducing special equipment to place fertilizer in bands below the surface of established swards. For establishing lucerne and other ley crops, where fertilizers may be applied at or before sowing, there are no advantages from using special drills to place the full dressing of fertilizer at a safe distance to the side of the seed. Where combine-drills are used for sowing herbage crops they should be modified to place a small quantity of superphosphate directly beneath the seed and the remainder of the fertilizer should be broadcast before sowing.
Population dynamics of the Dexter breed of cattle
Authors: Young G. B.
Published: March 2009

1. It is possible for a breed of cattle to persist and to expand slowly, despite the existence of a genetic defect which prevents 50% of the calves born being used for breeding. Moreover, it is possible to exert a certain amount of selection in such a breed. The Dexter breed provides an example.

2. Before 1924, about 64% of entrants to the breed were from inspected animals. Between 1924 and 1939 the breed contracted. From 1940 to 1947 the breed expanded.

3. During the period of decline almost every Dexter-type female born was registered and raised. The wastage rate and age distribution of the cows are similar in Dexters to those of other breeds. There would appear to have been comparatively little breeding from Kerry types. The average registered reproductive rate of Dexter-type females was about 0·8.

4. While it was not possible to examine the breed structure in the period of expansion, this was probably accomplished by lengthening the average productive life of the female, and possibly also by breeding from Kerry types.

5. The possibility of exercising selection in Dexters is shown to exist. Only about 13% of the females registered are used for producing registered bulls. Of the total bull crop, only about 7% are used to produce registered females, but the bulls selected have different numbers of offspring. The use of bulls selected after progeny testing is hardly feasible in Dexters. The increased numbers of females necessary in order to produce an adequate number of heifers, renders this technique almost impossible.

6. There has been little inbreeding in Dexters. This is possibly due to deliberate policy, as some of the breeders associate inbreeding with the production of monstrous calves.

7. It would, therefore, appear that the damaging effect of a lethal in a breed could be overemphasized.
Fatty acid composition of tail, subcutaneous and kidney fats of fat-tailed Awassi sheep
Authors: Al-Shabibi M. M. A. , Juma K. H.
Published: March 2009

Fatty acid composition of tail fat (TF), kidney fat (KF) and subcutaneous fat from the rumps (SCF) of docked and intact fat-tailed Awassi sheep was studied.

Docking had no effect on the composition of KF. Kidney fat possessed harder characteristics due to its relatively higher content of saturated fatty acids as compared with SCF or TF.
Effect of feeding water-soaked and dry wheat straw on feed intake, digestibility of nutrients and VFA production in growing zebu and buffalo calves
Authors: Chaturvedi M. L. , Singh U. B. , Ranjhan S. K.
Published: March 2009

Experiments were conducted on 12 male growing calves of zebu cattle (Bos indicus) and buffalo (Bos bubalis) to study the effect of feeding wheat straw presoaked with water on the voluntary feed intake, digestibility coefficients of nutrients and volatile fatty acid concentration and production. The feed intake was improved significantly (P < 0·05) in both the species as a result of soaking. The digestibility of crude protein and crude fibre was depressed (P < 0·05), whereas the nitrogen-free extract utilization increased significantly (P < 0·01) on soaking of straw. The availability of digestible energy and metabolizable energy was also more as a result of water treatment of wheat straw. The production rates of total volatile fatty acids and acetic acid were higher in both the species fed on water-soaked wheat straw. It is concluded that pre-soaking of wheat straw for 1–2 h with ordinary tap water may give an overall beneficial effect in both zebu and buffalo calves.
A note on the influence of the pattern of live-weight and body condition recovery between weaning and mating on food consumption and reproductive performance of Scottish Blackface ewes
Authors: Gunn R. G. , Doney J. M.
Published: March 2009

Previous studies on the Scottish Blackface breed have shown that ovulation rate and lambing performance are closely related to body condition at mating. Ovulation rates greater than two were achieved from ewes in good body condition (grade 3·0 on a scoring system described by Russel, Doney & Gunn, 1969) and this performance was not affected by condition either rising or falling to the pre-determined grade at mating (Gunn, Doney & Russel, 1969). Ewes in lower body condition at mating (described by grades 1·5, 2·0 and 2·5) were found to have correspondingly lower mean ovulation rates (Gunn et al. 1969; R. G. Gunn and J. M. Doney, unpublished). In these, and other experiments giving similar results, the experimentally controlled changes in nutrition and hence body condition were imposed for only a few weeks prior to mating, i.e. during late October and November. However, in traditional hill grazing systems, ewe recovery may be expected earlier and may be followed by a considerably longer period of live-weight and condition maintenance. In situations where some degree of grazing control can be used to modify the nutrient intake cycle, it is important to know if food consumption and subsequent reproductive performance can be influenced by the long-term pattern of recovery.
Studies in grazing management. III The behaviour of dairy cows grazed under the close-folding and rotational systems of management
Authors: Waite R. , MacDonald W. B. , Holmes W.
Published: March 2009

1. Two groups, each of six Ayrshire dairy cows, have been watched in the field for a total of twentytwo 24 hr. periods during the months May to September. No supplementary foods were fed at any time. One group grazed under a system of close-folding and the other in small rotational paddocks.

2. The effect of the different systems of management was small. It was clear, however, that closefolding increased the time spent in grazing and decreased the weight of herbage eaten. The milk yields from both groups were very similar.

3. A very constant pattern of behaviour over the 24 hr. period, similar for both groups, was observed. The most prolonged grazing period always occurred immediately after the cows returned from evening milking.

4. The amount of grazing during the hours of darkness was small at all times of the season but tended to increase as the evenings shortened and the nights lengthened. The cessation of evening grazing was closely linked with the fall of darkness at all times of the year.

5. The activities during the ‘day’ period were less regular but, nevertheless, showed a marked division into three main spells of grazing, of which one occurred immediately after morning milking, separated by two main spells of rest.

6. Stage of lactation, individual milk yield and live weight appeared to have no direct relation to the amount of time spent in grazing. Cows watched in both 1949 and 1950 grazed for very similar times despite differences in their stage of lactation.

7. Increasing defoliation of the paddock resulted in an increased grazing time by the rotationally grazed cows.

8. Close-folded cows grazed for a shorter time on herbage of low moisture content than on herbage of high moisture content, whilst eating virtually the same weight of dry matter.

9. Climatic changes to the extent met with in south-west Scotland had only a limited effect on the general pattern of grazing.

10. The physiological activities of dunging, urinating and drinking showed only small day to day variations.

11. The distance walked during grazing in the 24 hr. by one individual cow from each group showed only a slightly longer track for the rotationally grazed animal, the average distance being about 2000 yards.
Effects of growth regulators and controlled atmosphere on stored carrots
Authors: Abdel-Rahman M. , Isenberg F. M. R.
Published: March 2009

Preharvest sprays with 6-hydroxy-3-(2H)-pyridazinone (MH), or immersion in solutions of MH, 2,4-dichlorophenoxyacetic acid (2,4-D), 2-chloroethylphosphonic acid (ethephon), coumarin or (2-chloroethyl) trimethylammonium chloride (CCC) inhibited both sprouting and rooting of treated carrots during storage at 0 °C whencompared with water-dipped or untreated carrots, while N-6-benzyl-adenine (BA) dips stimulated extensive rooting and sprouting. In contrast, immersion in gibberellic acid (GA3) solutions had very little effect.

Storage atmospheres containing 1, 2.5, 5 or 10% oxygen inhibited both sprouting and rooting but increased mould infection. Atmospheres containing 21% (air) or 40% oxygen reduced mould infection, but increased sprouting and rooting of stored carrots. Washing carrots in water before storage did not significantly affect mould infection, while washing in 0.5% clorox increased it. However, washing in water followed by immersion in MH inhibited both sprouting and rooting and also reduced mould infection. ‘Jumbo’ and large-size carrots stored better than medium and small carrots.
Effect of sowing date and soil type on yield, yield components and survival of dry beans (Phaseolus Vulgaris L.)
Authors: Ishag H. M. , Ayoub Ali T.
Published: March 2009

Field experiments were conducted on clay and sandy clay-loam soils to investigate the effects of sowing date on the incidence of plant losses. Early sowing dates from 2 to 23 September resulted in very low seed yield (360 kg/ha) mainly because fewer plants survived. High air temperature increased the rate of plant death which was highly correlated with degree days, r = +0·95.

Number of plants/m2 was the predominant factor determining seed yield and number of pods/plant could not compensate for loss of plants.
Effects of differences in date of ear emergence and height on yield of winter wheat
Authors: Innes P. , Hoogendoorn J. , Blackwell R. D.
Published: March 2009

Early and late, and short and tall lines were selected from a cross between the winter wheat varieties Norman and Talent. All short selections carried the Rht2 dwarfing gene while the tall ones did not. The selections were compared in field experiments at the Plant Breeding Institute in Trumpington and at The Murrays Experimental Farm of the Scottish Crop Research Institute near Pathhead. In one of the experiments at Trumpington the plots were automatically sheltered from rain and the effects of withholding water before anthesis and withholding water during grain filling were studied.

In all trials the early selections gave grain yields equal to or greater than the late selections. There were no differences in number of ears/m2 or in number of grains per ear between the early and the late selections. Mean weight per grain of the early selections was greater than that of the late selections.

The short selections gave grain yields equal to or greater than the tall selections, except when water was withheld during grain filling in the sheltered experiment. There were no differences in number of ears/m2 between the short and the tall selections. The number of grains per ear was greater and mean weight per grain was less for the short selections than for the tall selections.

It is concluded that for general fitness to U.K. conditions, new varieties should be semi-dwarf, but earlier than current varieties.
The digestibility by sheep and goats of five roughages offered alone or with concentrates
Authors: Antoniou T. , Hadjipanayiotou M.
Published: March 2009

The digestive efficiency, rumen fermentation pattern, nitrogen balance, water intake and urine excretion were compared using four mature vasectomized Chios rams and four Damascus goats for each of five roughages (barley, lucerne or sudax hay, barley straw and leaves and twigs of acacia) offered alone or with concentrates (1:1 ratio), at approximately the maintenance energy level.

There were no species differences in the apparent digestibility of nutrients when the roughages were offered alone except for the significantly higher digestibility of dry matter, organic matter (OM), and gross energy (GE) of straw by goats. Sheep exceeded goats significantly in the digestibility of D.M., OM, GE and crude protein (CP) of lucerne hay plus concentrate and of CP when barley hay or sudax hay were supplemented with concentrate.

Compared with sheep, goats tended to consume more D.M. per kg W0·75 and drink less water and excrete less urine, but significant differences for water were obtained only with barley straw plus concentrate and for urine with barley hay and acacia.

Daily protein retention (g/kg W0·75) was consistently lower in goats than sheep but significant difference was obtained with acacia and with lucerne hay or straw plus concentrate. These results would suggest that Damascus goats require more protein for maintenance than sheep.

Compared with sheep, goats had significantly higher rumen NH3·N concentration with both acacia diets but lower with lucerne hay.

Total VFA concentration tended to be higher in sheep with all diets, but significance was observed only with barley hay although rumen pH was lower (acacia diets) or similar compared with goats. The molar proportion of acetic was significantly higher in sheep than goats with barley hay plus concentrate. Goats exceeded sheep significantly in the proportion of propionic with straw, of butyric with both barley hay and sudax hay plus concentrate diets, and of isobutyric with barley hay or acacia plus concentrate; with the other diets goats tended to have higher proportions of butyric and isobutyric.
The effects of consolidating the soil beneath potato seed tubers and of inter-row grubbing on the growth and yield of the crop
Authors: Beveridge J. L. , Hanley F. , Jarvis R. H.
Published: March 2009

1. Three experiments designed to investigate the effects of consolidation and aeration of soil beneath potato seed tubers before planting, and inter-row grubbing after planting, on the growth and yield of potatoes are described and the results discussed.

2. Consolidation of furrows beneath seed tubers by tractor wheels at planting had no effect on total weight of ware-size tubers produced but increased the weight of mis-shapen waresize tubers. It is argued that this effect was related to soil moisture content and tilth at planting time.
Seed ripening in grasses. I. Changes in carbohydrate content
Authors: Stoddart J. L.
Published: March 2009

1. In grass seed crops accurate assessment of the optimum harvest date is made difficult by the lack of knowledge of seed ripeness. In order to define ripeness in physiological terms studies have been initiated the first of which is described in this paper.

2. Samples of Aberystwyth S. 321 perennial ryegrass (Lolium perenneL.), S. 143 cocksfoot (Dactylis glomerataL.), S. 48 and S. 352 timothy varieties (Phleum pratense L.) were taken at 3-day intervals from inflorescence emergence to seed harvest. These were analysed for total 80 % ethanol soluble carbohydrates (TSC) reducing sugars, sucrose and starch, whilst duplicate samples were air-dried for determination of thousand seed weight and percentage germination.