bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of the value of repeated backcrossing of a pentaploid hybrid ofTriticum vulgare(cult. var. Little Joss) andT. Turgidum(cult. var. Rivett)
Authors: Engledow F. L. , Bell G. D. H. , Lupton F. G. H. 
Published: March 2009

1. Selections from a cross of varieties ofTriticum vulgareandT. Turgidumhave been backcrossed repeatedly to theturgidumandvulgareparents and selections ofturgidumandvulgaretype respectively made within each series.2. The yield and morphological stability ofturgidum-andvulgare-type selections from the straight cross have been compared with those of selections backcrossed up to four times toT. turgidumandT. vulgarerespectively.3. In the case of backcrosses toT. Turgidumthe highest yielding selections have been derived from the most frequently backcrossed material, but thevulgare-type selections from the straight cross have outyielded those from the material backcrossed toT. vulgare.4. An analysis of the yield components of the parents and of the most promising selections, in terms of ears per plant, spikelets per ear, grains per spikelet and 1000-grain weight, has shown no evidence of a combination of the characters determining the high yield of the parents in these high yielding selections.
Effects of stage of maturity, nitrogen application and swath thickness on the field drying of herbage to the hay stage
Authors: Wilman D. , Owen I. G. 
Published: March 2009

SUMMARYHerbage from a grass-white clover sward was dried in the field to the hay stage (< 0·3 g moisture/g dry matter) at four times of year in 2 years comparing, in each case, all combinations of three stages of maturity, three levels of applied nitrogen and three thicknesses of swath; 35, 55 and 75 days' regrowth, 0, 75 and 150 kg N/ha and, on average, 220, 474 and 728 g herbage dry matter/m2 were compared.The least mature herbage had the highest moisture content at the time of cutting and dried most quickly at a given swath thickness, being slightly drier than the more mature herbage at the hay stage. At the cuts in late May-early June and late Juneearly July, when the crop was predominantly grass, the application of nitrogen increased both the moisture content at the time of cutting and the initial rate of drying at a given swatli thickness, so that in the middle and later stages of drying there was no effect of applied N on moisture content. At the cuts in early and late August, herbage from the plots that had received no applied N, which contained a substantial amount of white clover, had the highest moisture content at the time of cutting, dried fastest at a given swath thickness and had the lowest moisture content in the later stages of drying. In the very early stages of drying, herbage in a thin swath lost water much faster than herbage in a thick swath, but subsequently the rate of drying was consistently faster in a thick than in a thin swath so that, by the hay stage, herbage in a tick swath was at least as dry as herbage in a thin swath. There was almost no interaction between the different types, of treatment.Rain during the drying period had little or no effect on the nitrogen content of the crop, but reduced digestibility by about 9 units. Stage of maturity and swath thickness did not affect the extent of this reduction in digestibility.
The digestibility of grass by young calves
Authors: Preston T. R. , Archibald J. D. H. , Tinkler W. 
Published: March 2009

1. The efficiency with which Ayrshire calves digested the dry matter of fresh grass was measured over two trial periods extending from the third to the tenth week of age.2. A statistical method for determining digestibility coefficients is outlined and its advantages over the conventional procedure, particularly for young growing animals, are discussed.3. The mean coefficient of digestibility of the dry matter of the grass for four calves was 74·6%.4. This digestive efficiency was attained immediately the grass was fed and did not vary throughout the experiment.5. Simultaneous feeding of milk in the first trial period did not affect the digestion of grass.
A study of subclinical worm infestation in sheep: I. The effect of level of infestation on the growth of the lamb
Authors: Spedding C. R. W. , Brown T. H. 
Published: March 2009

1. The experiment described confirmed earlier findings that a folding management across wormfree pasture was capable of preventing infection of the lamb by all species except Strongyloides papillosus.2. The growth and productivity of lambs infected at five different levels were compared with those of ‘worm-free’ controls grazing with them.3. Live-weight gain of the total infected group was significantly depressed; within the infected group only level 5 differed significantly from the control group.4. Loss of productivity was, in this experiment, associated with egg counts between 30 and 57 e.p.g.5. The problem of definig a ‘tolerance’ level below which no appreciable damage occurs is discussed in relation to the results obtained.
The problem of assessing strains: A study in grass-breeding technique
Authors: Lazenby Alec 
Published: March 2009

1. This paper reports a study of the behaviour of five strains of ryegrass (Devon Eaver, Irish S. 24 and New Zealand certified mother perennial ryegrass and H.I) under three different conditions of spacing and two types of management. Strain performances are compared on the basis of green and dry-weight data of total herbage, and green weight of sown strain contributions under the three techniques of evaluation.2. Under both managements, the total annual production per unit area was greatest from broadcast and least from single-plant areas. Some individual cut yields were, however, greater than those from broadcast plots, with the drill-row production intermediate.3. Yield differences between the four perennial ryegrasses were greatest as spaced plants and least in broadcast plots. Single plants and broadcast plots of H. 1 were outstanding compared with the perennial strains. Under neither management were there significant interactions between strains and sowing method in 1952, though such interactions were detected in both cases during 1953.4. The relative yield performance of strains under similar spacing conditions were almost identical under both managements.
Studies on lucerne and lucerne-grass leys: IV. The effect of systems of grazing management on the persistence of a lucerne-cocksfoot ley
Authors: Barker M. G. , Hanley F. , Ridgman W. J. 
Published: March 2009

1. Experiments to assess the effects of grazing management on the persistence of a lucerne-cocksfoot ley are described and the results discussed.2. The work confirms the general opinion, based on other experiments in which lucerne was defoliated by cutting, that frequent defoliation causes a reduction in the persistence of the lucerne.3. Defoliation at 8-weekly intervals maintained a satisfactory balance between the sown species in a lucerne-cocksfoot sward, irrespective of whether defoliation was by cutting or by grazing or by combination of the two.4. Grazing at 4-weekly or 2-weekly intervals led to serious reductions in the proportion of lucerne in the sward.5. The provision of a rest period, either early or late in the growing season, had little effect on the amount of lucerne present after 2 years on plots subjected to grazing at 4-weekly or 2-weekly intervals.
The apparent digestibility of crude protein by the ruminant: I. A synthesis of the results of digestibility trials with herbage and mixed feeds
Authors: Glover J. , Duthie D. W. , French M. H. 
Published: March 2009

The apparent digestibility of crude protein by cattle and sheep of different breeds and types, both temperate and tropical, has been studied by means of an analysis of the results of feeding trials with herbages and mixed feeds in many parts of the world. No matter whether herbages or mixed feeds are used the digestibility coefficient (y) is shown to be related to the percentage crude-protein content of the feed (x) by means of an expression of the form y = a + b log x. The particular equation y= 70 log x − 5 is shown to give a reasonable fit of all the available data.The digestibility of crude protein in the feed is shown to increase very rapidly at low protein levels (from about 2 to 9%), and there after it rises more slowly as the crude-protein content increases.There is close agreement between the equations for herbage fed alone and for mixed feed which suggests that the total percentage of crude protein in the feed, irrespective of its nature, determines the digestibility of the protein.
A simple method of using highly saline water for irrigation
Authors: Hussain Z. 
Published: March 2009

SUMMARYHofuf-Alhassa is one of the important agricultural areas of the Kingdom of Saudi Arabia. The water available for irrigation purposes is limited in quantity and saline in nature.To maximize the use of available water sources, a technique is described to mix irrigation water with drainage water, taking into consideration the salt balance effect in the soil under the Alhassa conditions.
Changes occurring in cattle as a consequence of selection for growth rate in a stressful environment
Authors: Frisch J. E. 
Published: March 2009

SUMMARYSince 1966 a closed line of Hereford × Shorthorn cattle (selected line) has been selected principally for growth rate under conditions of moderate to high environmental stress. Responses in growth rate were measured over the years 1970–5 as differences from an unselected control line. Birth weight declined but live weight at all other ages increased.Groups of animals were taken from each line in 1976 and 1977 and used to determine the reasons for the differences in growth rate. Growth rate of the groups was measured when they were exposed to several different levels of stress, namely, the plane of nutrition, high ambient temperature, infection with bovine infectious keratoconjunctivitis(BIK) or gastro-intestinal helminths. The selected line was shown to be more heat tolerant, to have lower maintenance requirements and greater resistance to infection with BIK and helminths and, in consequence, always had higher growth rates in the presence of these stresses. However, they did not have superior growth rate at low levels of these stresses. Thus, selection had not increased the components associated with growth potential, and the improvement in growth rate was achieved entirely through increases in resistance to environmental stresses which affected growth rate.The application of these findings to selection for growth rate, particularly in harsh environments, is discussed.
The effects of drought on barley: soil and plant water relations
Authors: Day W. , Lawlor D. W. , Legg B. J. 
Published: March 2009

SUMMARYIn a field experiment on the effects of drought on spring barley, the crop was protected from rainfall by automatic rain shelters; a range of drought treatments was achieved by irrigating various plots according to a predetermined schedule. There were 12 treatments which ranged from no irrigation to full irrigation from emergence to harvest; results from seven treatments are discussed in this paper.The rate of water uptake was determined for four soil horizons centred at 0·15, 0·50, 0·80 and 1·10 m. For all treatments, the rate of uptake in each horizon decreased as the soil dried, and although there were large differences in root density between horizons, maximum rates of uptake were similar in all horizons down to 0·80 m. Treatment effects showed that prolonged drought decreased the rate of uptake from the 0·80 and 1·10 m horizons: root density at and below 1·0 m probably differed between treatments.Differences between treatments in leaf water potential (ψL) and osmotic potential (πL) were small, and there was no evidence that osmotic adjustment contributed to the drought response of this crop. Near anthesis, pre-dawn ψL was near zero for irrigated treatments and between – 3 and – 5 bar for unirrigated. During the day, ψL decreased to a minimum of – 15 to – 18 bar for irrigated plants, and was generally 3 bar lower for unirrigated. For all treatments, ψL was greater than π for the major part of the day, i.e. positive turgor was maintained; however, turgor was usually greater for irrigated than for unirrigated plants. The relationship, for leaf 8, between ψL and transpiration flux density was markedly non-linear, and was of a similar form for irrigated and vinirrigated plants. As the form of this relationship was independent of treatment, the non-linearity could not have been caused by variations in soil water potential through the profile.Stomatal resistance differed markedly between treatments. A detailed analysis is presented, relating measured resistance for leaf 8 to ψL and to environmental variables: irradiance (I), water vapour pressure deficit (vpd), and temperature (T). The analysis showed no significant dependence of resistance on ψL or T, but marked dependence on I and vpd; a mathematical model combining a hyperbolic response function for I and an exponential function for vpd fitted the data well. The responses of abaxial and adaxial surface resistances to vpd were similar, but their light responses differed because of their different exposures to incident irradiance.
The effects of irrigation, nitrogen fertilizer and the control of pests and pathogens on spring-sown field beans (Vicia fabaL.) and residual effects on two following winter wheat crops
Authors: McEwen J. , Bardner R. , Briggs G. G. , Bromilow R. H. , Cockbain A. J. , Day J. M. , Fletcher K. E. , Legg B. J. , Roughley R. J. , Salt G. A. , Simpson H. R. , Webb R. M. , Witty J. F. , Yeoman D. P. 
Published: March 2009

SUMMARYExperiments started in 1976, 1977 and 1978 on Clay-with-Flints soil at Rothamsted tested the effects of combinations of eight two-level factors on spring-sown field beans. Factors tested, presencev. absence, were irrigation, nitrogen fertilizer, aldicarb, fonofos (dieldrin in 1976), benomyl to the seed bed, permethrin (fenitrothion in 1976), pirimicarb, benomyl foliar spray (not tested in 1976).The main pests and diseases present were nematodes of the genusPratylenchus, the pea aphidAcyrthosiphon pisum, the pea and bean weevilSitona lineatus, root blackening associated with the fungal generaPythiumandFusarium, the foliar diseases chocolate spot,Botrytisspp., rust,Uromyces fabaeand bean leaf roll virus.Incidence of these pests and diseases varied between years. Controlling those present increased yield by about 0·7 t grain/ha each year. The difficulty of apportioning this increase to particular pests and diseases is discussed.Irrigation increased total dry-matter production and grain yield in 1976 and 1978 but only total dry-matter production in 1977, when grain yield was lost because of lodging. Nitrogen fertilizer had little or no effect.The most favourable combinations of treatments gave yields of 3·4, 5·0 and 6·4 t grain/ha in the 3 years respectively. Small yields in 1976, despite irrigation, were attributed to premature senescence caused by exceptionally high temperatures. It is suggested that with good control of pests and diseases yields of at least 5 t/ha should be attainable on Clay-with-Flints soil without irrigation in years of average temperature and rainfall and yields in excess of 6 t/ha when the soil-moisture deficit is lessened by either above-average rainfall or irrigation.Treatments applied to the beans had little or no effect on two following crops of winter wheat.
Effects of nitrogen and its carriers with different topping heights on growth, yield and quality of tobacco
Authors: Mahadik S. R. 
Published: March 2009

SUMMARYIn this investigation the largest amount of nitrogen used, 44 kg per hectare, increased leaf size, yield and amount of nicotine in the leaf. The three carriers of N had similar effects on growth and yield at each amount applied but calcium ammonium nitrate produced tobacco inferior in quality to that with ammonium sulphate and urea. Increasing topping height from 8 to 10 and to 12 leaves increased the total leaf area per plant and yields, delayed maturity and lowered the quality of the tobacco. The greatest yield was produced by using 44 kg of N and topping at 12 leaves, but the best quality resulted from using 44 kg of N and topping at 8 leaves.
Ryegrass populations from intensively managed leys III. Reaction to management, nitrogen application and Poa trivialisL. in field trials
Authors: Charles A. H. 
Published: March 2009

SUMMARYPopulations of Lolium perenneL. derived from fields where the management was paddock grazing were compared with plants from breeder's seed of the cultivars originally sown at the collection sites. In the first trial the ‘survivor’ population derived from an S. 24 ley was better adapted to withstand intensive sheep grazing and high nitrogen application (672 kg/ha/ annum) than either S. 24 or Stormont Zephyr. Extra treading by sheep in addition to that involved in the high stock density (1186sheep/ha) used at the time of grazing produced only a small reduction in yield of dry matter. In the second trial, the ‘survivor’ population derived from an S. 23 ley had a higher yield of dry matter than S. 23 at the high level of N application (672 kg/ha/annum). There was no difference in the yields when 168 kg N/ha/annum was applied. In both field trials yield in the year of sowing was high for all swards, although the survivor populations were slower to establish than the original cultivars. The evaluation of the ryegrass populations in terms of dry-matter yield was affected by the small quantity of Poa trivialispresent when this grass was sown with the ryegrasses. In the second trial this conclusion also applied to yield of nitrogen in the herbage.
Ripening of grain maize in England: varietal differences in ripening patterns
Authors: Bunting E. S. 
Published: March 2009

SUMMARYChanges occurring during ripening in dry weight and percentage dry-matter content of grain and rachis (cob) have been studied in Inra 200, and comparable data obtained for a U.S.A. dent hybrid, Minnesota 803, a Canadian flint × dent hybrid, OX 302, and a range of European flint × dent hybrids (Prior, Kelvedon 59A, De Kalb 202, Maris Carmine, Pioneer 131 and Anjou 210).In Minnesota 803, OX 302 and, to a lesser extent, Prior, loss of water from the grain was more rapid than in Inra 200 during later stages of ripening. OX 302 reached a harvestable stage (40% grain water content) 10–12 weeks after silking, about 7 days earlier than Inra 200 in favourable seasons, and nearly 14 days earlier when conditions for ripening were less satisfactory. The patterns of changes occurring in the cob were quite different from those in ripening grain. Maximum dry weight of cob was reached when the grain was in the milk stage, and then declined throughout the period of rapid grain development; in the ripe ear, cob dry weight was 15–20% below its earlier maximum. At comparable grain water contents, the cob in Inra 200 was wetter than in Prior, Minnesota 803 and, even more markedly, OX 302. In contrast, water content in the cob of Maris Carmine and Anjou 210 was slightly higher than in Inra 200. The possible relationship between the differing varietal trends in ripening grain (and cob) and resistance to stalk rot is discussed.The dry weight of the cob in ripe ears of Inra 200 was barely half that found in OX 302 and Minnesota 803, and lower than in other European flint × dent hybrids. Shelling percentage in ripe ears of Inra 200 was 88–90; it was 84–86 in other European flint × dent hybrids, about 80 in Minnesota 803 and 75 in OX 302. Mention is made of the relevance of this information to choice of variety for production of ground ear maize.
Reproduction in the buffalo-cow: pH of the vaginal secretions
Authors: Shalash M. R. 
Published: March 2009

1. Fifty buffalo-cows were used for studying the pH of the vaginal secretion at different stages of the sex cycle.2. Highly significant differences were found in the pH value of the vaginal secretions during the different stages of the sex cycle. The average was 7·3 during oestrus, 8·1 during dioestrus and 8·3 during pregnancy.
Studies on forage cell walls: 4. Flow and degradation of alkali-treated rice hull digesta in the ruminant digestive tract
Authors: McManus W. R. , Choung C. C. , Robinson V. N. E. 
Published: March 2009

SummarySheep weighing 27 kg live weight were fed ad libitum three pelleted diets containing alkali-treated ground rice hulls (0, 5 and 15 g NaOH/100 g rice hull dry matter) in a 1:1 ratio with ground non-alkali-treated lucerne and were fed a fourth diet comprising the above control pellet fed ad libitum with a wheat grain supplement to determine the effects of alkali treatment and of energy supplementation on the digestion of cell walls and to assess the dynamics of flow of digesta through the gastrointestinal tract.Flows of organic matter (OM) and nitrogen (N) to the duodenum were not different for the four diets, but daily whole digesta flow past the duodenum was greater (P < 0·01) for the two alkali-treated diets. Alkali treatment of rice hulls increased the percentage of total digestion of OM that occurred in the foregut (68%) compared with non-alkali-treated diets (52%), did not increase total volatile fatty acid concentration in rumen liquor, or adversely increase rumen pH. The capability of rumen microbiota to synthesize ammo acids was not adversely affected by alkali treatment. The percentage unit digestibility of cell wall constituent OM in the whole tract was increased approximately 1·6-fold by alkali treatment. Grain supplementation increased diet digestibility.Scanning electron microscope studies revealed confirmatory visual evidence of enhanced degradation of alkali-treated rice hulls in the tract. It is clear from these studies that alkali treatment has caused sheets of silicified cuticle on the outside of rice hulls to dissolve and to lift away from the underlying lignocellulosic (palisade) matrix. It is also clear that this matrix material is itself heavily mineralized. Disappearance of silica across the gut wall was greatest for animals fed alkali-treated diets. No clinical signs of urolithiasis were seen. Sheep readily coped with the sodium intake (33 g/day) associated with alkali-treated diets, partially by an increased water consumption and a greater ruminal and intestinal absorption of this electrolyte.It is calculated that the OM intakes recorded and nutrients released from alkalitreated rice hull diets provided between 500 and 600 kcal net energy/day.
Evaporative water loss in domestic fowls and its partition in relation to ambient temperature
Authors: Richards S. A. 
Published: March 2009

SummaryThe rate of evaporative water loss has been studied in domestic fowls in the ambient temperature range from 0 to 40°C.Results for whole-body evaporation were similar when obtained by the open-flow and direct-weighing methods. At low levels of absolute humidity the rate increased by 0·03 mg/(g.h.°C) from 0 to 22 °C and by 0·17 mg/(g.h.°C) from 23 to 40 °C. Wholebody evaporation decreased with rising ambient water vapour pressure by 0·7 mg/(g.h.kPa).Cutaneous water loss was greater than respiratory water loss below 21 °C; it accounted for 78% of whole-body evaporation at 0 °C, falling to 25% at 40 °C.The rates of respiratory and whole-body evaporation could both be expressed as linear functions of respiratory frequency.