bluuebunny/crossref_metadata_2025_split huggingface dataset:
An assessment of varietal resistance to chocolate spot (Botrytis fabae) infection of field beans (Vicia faba L.), with some indications of its heritability and mode of inheritance
Authors: Elliott Jennifer E. M. , Whittington W. J. 
Published: March 2009

SUMMARYVarietal differences in resistance to non-aggressive chocolate spot infection were detected in the field, although complete resistance was not observed. Following artificial inoculation under growth-room conditions, a parent–offspring regression of disease scores for the heterogeneous stock Chivers was estimated as 0·51 ± 0·24, and although this cannot be regarded as a reliable heritability estimate, it demonstrates a degree of additive genetic control. AnF2diallel cross, under field conditions, indicated resistance to be controlled mainly by dominant alleles within a system of partial dominance. Detached-leaf tests indicated that within virtually complete dominance systems, dominant alleles facilitate fungal penetration and induce a hypersensitive response within the leaf. Control of further lesion development was indicated to be effected by a virtually complete additive system.
Morphological and physiological variation in wild oats (Avena fatua L. and A. ludoviciana Dur.) and in hybrids between wild and cultivated oats
Authors: Thurston Joan M. 
Published: March 2009

In samples of wild-oat panicles collected in England and Wales in 1951 only two species, Avena fatua L. and Avena ludoviciana Dur., occurred; both were very variable in grain characters but most plants bred true. Plants of all except one type of A. fatua were upright in habit with few tillers and averaged 95% dormant grains at harvest; plants of A. ludoviciana were procumbent or prostrate at the maximum tillering stage with numerous tillers and the percentage dormant grains was lower than in A. fatua.The taxonomy of wild oats is discussed. Chromosome counts on eleven selections showed that 2n = 42.Types intermediate between wild and cultivated oats were compared with wild oats.
Developmental analysis of populations in the cereals and herbage grasses: II. Response to low-temperature vernalization
Authors: Cooper J. P. 
Published: March 2009

A range of populations of cereals and herbage grasses, mainly of Lolium, Phieum and Triticum, have been tested in the greenhouse for response to lowtemperature vernalization. Leaf number before heading was used as the measure of reproductive development.A close correlation was found between the climatic or agronomic origin of each population and its response to low temperature. In the cereals, response to low temperature was found in one ecological group only, namely, the winter wheats from western Europe. In Lolium the duration of the life cycle is closely related to the response to vernalization. The annual strains, such as Westernwolths or Wimmera ryegrasses, head rapidly with little or no response, while most of the perennial strains have an obligatory requirement for low temperature. In Phieum none of the populations tested exhibits any marked response to, or requirement for, low temperature, but the rapidity of heading, as measured by leaf number, varies from strain to strain and shows a high correlation with persistency. Most of the weed species tested are short-lived annuals and show little or no response to low temperature.For each population, the local climate and farming system determine the optimum life cycle, and response to low temperature forms one important mechanism whereby such a life cycle can be attained.The value of these methods for varietal classification and identification was assessed by comparing the behaviour of the same material in two or more seasons or under two or more kinds of equipment. The type of lighting used to provide long-day or continuous illumination, and the date of sowing, have a differential effect only in Phalaris and Phleum. In the other material, while variations in sowing date produce slight differences in the leaf number, the interaction between strain and sowing date is small, and good discrimination between population samples is possible. It is important to keep the greenhouse temperature between 50 and 70° F. to avoid natural vernalization or devernalization of material. The use of probit diagrams for comparing truncated distributions is discussed.It is suggested that the methods can also be used to assess the genetic variation within populations. In the present results, the effect of the breeding system on the storage of variation is well shown. In self-fertilizing species, little or no variation is carried within lines, or, in the one case tested, between stocks of the same variety; it can, however, be carried between lines in a local population. In outbreeding species, each population carries considerable variation, both as genetic differences between individuals and in the heterozygous condition within individuals.
Compensation in spring-sown oil-seed rape (Brassica napus L.) plants in response to injury to their flower buds and pods
Authors: Tatchell G. M. 
Published: March 2009

SUMMARYThe extent and possible mechanism by which spring-sown oil-seed rape plants can compensate for insect or artificial injury to flower buds and pods were investigated by examination of the yield, and its components, of plants collected from commercial fields and those grown in field cages and glasshouses. Plants were able to compensate and in some instances overcompensate for all observed levels of M. aeneus injury or artificial bud removal by the production of more axillary racemes, which may be due to the loss of apical dominance. Artificial injury to the pods or infestation by C. assimilis larvae did not result in a significant reduction in the yield of seed and was compensated for partly by a slight increase in the number of axillary racemes and by slight increases in the number of pods on each axillary raceme and in the 1000-seed weight, and resulted mainly from the diversion of nutrients to other yield-bearing organs. Injury by D. brassicae larvae was partly compensated for in 1975 and at lower injury levels in 1974 and involved a similar mechanism to compensation for C. assimilis injury. These results are discussed in relation to the observed infestation levels in field surveys and current control practices.
Effects of several nitrification inhibitors, when injected with aqueous urea, on yields and nitrogen recoveries of ryegrass leys
Authors: Rodgers G. A. , Widdowson F. V. , Penny A. , Hewitt M. V. 
Published: March 2009

SUMMARYSeveral nitrification inhibitors were compared with nitrapyrin, which was taken as the standard, when injected with aqueous urea into ryegrass leys at Rothamsted during 1977–81 and at Liscombe Experimental Husbandry Farm, Dulverton, Somerset, during 1977–9. Injection was done in either autumn or winter or spring.All the inhibitors slowed down the rate of nitrate formation from the injected urea. Sodium trithioearbonate (STC) was less effective than nitrapyrin and potassium ethyl xanthate (KEtX) less effective than STC. A mixture of nitrapyrin and carbon disulphide was better than nitrapyrin alone, and a mixture of STO and KEtX was better than STC alone.At Rothamsted, injecting inhibitors in autumn or winter improved yields and N uptakes, probably because they prevented loss of nitrate N by leaching and perhaps by denitrification. STC, STC-KEtX mixture and etridiazole were as good as, and nitrapyrin–CS2 mixture better than, nitrapyrin alone. Injecting inhibitors in spring frequently decreased yields, perhaps because NH4:NO3 ratios were too large, and increased them only when more than 150 mm of rain fell afterwards.At Liscombe, where rainfall was higher, but soil temperatures were similar to those at Rothamsted, the benefits from using inhibitors in autumn were larger, but there were none from using them in spring.
The effects of fertilizers and drought on the concentrations of potassium in the dry matter and tissue water of field-grown spring barley
Authors: Leigh R. A. , Johnston A. E. 
Published: March 2009

SUMMARYThe effects of N, P, K and Na silicate fertilizers, and drought on the concentrations of K in the dry matter and tissue water of field-grown spring barley crops have been investigated. Percentage K in dry matter depended on the amounts of N, P, K or water received by the crops and was linearly related to fresh weight to dry weight ratio, but the slope of this relationship depended on whether or not the crops received K. Expressing K concentrations on the basis of tissue water eliminated differences between crops, except for those given insufficient K. Barley crops given fertilizer K maintained K concentrations in their tissue water of about 200 mmol/kg tissue water for most of the growth period but crops grown without K had only 50–70 mmol/kg tissue water. The results indicate that K concentrations in the tissue water are a more reliable indicator of tissue K status than % K in dry matter.Decreases in crop K content resulting from poor K supply were balanced by increases in Na and Ca (but not Mg) contents so that total cation concentrations in the tissue water were similar in low and high K crops. The extra Na and Ca are probably primarily involved in maintaining charge balance for anion absorption but once in the plant they may also substitute for K in its osmotic role.
The effect of variation in the storage temperature of seed potatoes on sprout growth and subsequent yield
Authors: Wurr D. C. E. 
Published: March 2009

SUMMARYExperiments, conducted over 3 years, investigated the effect of all combinations of two storage periods at low temperature (0 or 2 °C) and two storage periods at 10 °C on the sprout growth, numbers of stems per tuber, foliage development and subsequent tuber yield of the two maincrop varieties Maris Piper and Désirée.Although the number of day-degrees accumulated during sprouting was the same for all treatment combinations, there were large effects of treatments on the number of sproutlets per tuber and the total sprout length per tuber. However, there was no effect on the number of stems per tuber, foliage development or saleable ware yield inany year.
Mineralization and field effectiveness of ordinary and coated urea, urea-aldehyde condensation product and urea treated with nitrification inhibitor
Authors: Nair K. P. P. , Sharma P. B. 
Published: March 2009

SUMMARYA laboratory incubation study followed by a field experiment was made in a silty clay loam soil (pH 6·9) at Pantnagar, India, on the effectiveness of ordinary urea, coated urea (sulphur and shellac-coated), urea-isobutyraldehyde condensation product (isobutylidenediurea, IBDU) and urea blended with nitrification inhibitor AM (2- amino-4 chloro-6-methylpyrimidine) and neem (a non-edible oil seed obtained from Azadirachta indica) cake. Whereas untreated urea and IBDU hydrolysed rapidly leaving no trace of urea-N after 2 weeks, sulphur-coated urea mineralized quite slowly and retained urea-N for as long as 4 weeks after incubation. Urea blended with neem cake was intermediate. Of all the materials tested, sulphur-coated urea showed maximum nitrification inhibition. A combination of one third sulphur-coated urea at planting + two thirds ordinary urea 30 days later yielded 12·3% more maize grain than ordinary urea in the same proportion at the same times of application.
The effect of planting density, inorganic nitrogen fertilizer and supplementary carbon dioxide on yield of Vicia faba L.
Authors: Day J. M. , Roughley R. J. , Witty J. F. 
Published: March 2009

SUMMARYVicia faba cv. Minden was planted at densities ranging from 6 to 98 plants/m2. Nitrogen was applied to the soil as split dressings or as a foliar spray. CO2 concentration in the canopy was increased in some plots to 0·22% for 3 weeks during the early pod-filling stage.Yield and number of seeds per plant varied inversely with plant spacing between 9 and 98 plants/m2. Mean seed weight increased up to 13 plants/m2 and then remained constant between 13 and 98 plants/m2. Yield/ha was unaffected by plant density above 18 plants/m2.Application of 200 kg N/ha as ‘Nitro-Chalk’ (mixture of NH4NO3 and CaCO3) to the soil as split dressings did not affect yield or its components but 80 kg N/ha as urea applied in four foliar sprays increased yield by 361 kg/ha (8·6%). Recovery of the labelled nitrogen in the grain varied from 28% when applied during vegetative growth to 8% when applied in the reproductive phase and 15% in the foliar spray.The highest yield (5·12 t/ha) was obtained by supplementary CO2. The results suggest that there is no advantage in applying fertilizer nitrogen to well-nodulated spring beans.
The effects of time of weed removal on growth and yield of sugar beet
Authors: Scott R. K. , Wilcockson S. J. , Moisey F. R. 
Published: March 2009

SUMMARYField experiments at Sutton Bonington between 1970 and 1974 tested how crop yields were affected by hand weeding at different stages in the life of early- and latesown crops. Losses where weeds were never controlled ranged from 95% where tallgrowingChenopodium albumL. predominated to 50% whenStellaria media(L.) Vill. andTripleurospermum maritimumL.) Koch ssp.inodorumHyl ex. Vaarama (T.inodorum) were most involved.In five of the seven crops examined the latest date (X) at which weeding had to commence to prevent irreversible effects on growth and yield and the earliest date at which weeding could cease without yield loss (Y) coincided. For late March/early April sowings this occurred 6 weeks after crop emergence, while for late April/early May sowings in which events were more rapid the same stage was reached 4 weeks after emergence. For an early-sown crop in 1973, when rainfall was frequent and heavy andC. albumprolific, X preceded Y with an interval of 4 weeks between the two dates (4–8 weeks after crop emergence, mid-May to mid-June). In complete contrast for a late-sown crop in 1974, when the weather was exceptionally dry andC. albumvirtually absent, Y preceded X and a single weeding at any time between 2 and 8 weeks after emergence would have prevented yield loss.Sugar beet had generally reached the late singling stage (4–6 true leaves) by the time weeding must have commenced. During the next 6 weeks, final yield was depressed by 120–150kg/ha (1·;5%) with each day that weeds were allowed to remain. However, leaf production continued throughout the season and the crop was capable of recovering from early checks caused by weed competition. It proved possible for crops whose weights were depressed by 25–30% when first weeded to recover completely by harvest.
Reproduction in farmed red deer. 1. Hind and stag fertility
Authors: Hamilton W. J. , Blaxter K. L. 
Published: March 2009

SUMMARYThe fertility of a stock of red deer kept under farming conditions on hill land over a period of 7 years has been assessed. The stock consisted of five cohorts of hinds born in successive years from 1971 to 1975. The fertility of hinds was related to their body weight by the general relationship P = 1 – exp(– 0·085(W– 52)) where Pis the probability that a hind will calve and W is her weight in kg at the time of the rut. When body weight was taken into account in this way, age had no effect on hind fertility. Fertility was, however, poor in one year following a rut which occurred in bad weather. Separation of calves from hinds at the time of the rut had no effect on fertility, and under the farm conditions there was no increase in fertility of hinds which had been barren the previous year above that expected from their body weight. Date of calving was slightly skewed, but 63 % of all calves were born in the first 20 days of June. Smaller hinds calved later; 1 kg body weight increased date of calving by about 0·3 days. Evidence of stag infertility was obtained and it was shown that one stag could effectively mate with 28 hinds such that they mostly calved within a 20-day period. It was possible to run 60 hinds with three stags and obtain calving rates which were similar to those for the hind population as a whole. There were no differences in fertility between matched groups of hinds exposed to one or two stags. The results are compared with those obtained by observation of wild stocks in Scotland.
Growth and development of bush tomatoes in relation to temperature
Authors: Gray D. , Ward J. A. , Steckel Joyce R. A. 
Published: March 2009

SUMMARYData are presented relating various stages of growth of field-grown bush tomatoes cv. Sleaford Abundance established from dry and pre-germinated seeds and from transplants to accumulated day-degrees. In general, Ontario units predicted the dates of 50% flowering, of the first harvest and the date when 37·5 t/ha of ripe fruit had been picked, more accurately than day-degrees above 10 °C or calendar days. The number of Ontario units from sowing to 50% flowering for dry and pre-germinated seeds were 956 ± 35 and 871 ± 85, respectively. The corresponding figures from sowing to first harvest were 1958 ± 59 and 1867 ± 85. For transplanted crops the number of Ontario units from planting to 50 % flowering and from planting to first harvest were 322 ± 62 and 1352 ± 133, respectively. For transplanted crops the number of Ontario units required to give a yield of ripe fruit of 37·5 t/ha (the minimum level currently necessary on economic grounds for tomatoes for processing) was 1937 ± 112. Using this figure in conjunction with long-term meteorological records it was estimated that crops established from transplants at East Mailing, Kent (latitude 51° N), would fail to give yields of ripe fruit of 37·5 t/ha by late September on only 1–6 occasions in 100 whereas at Wellesbourne, Warwickshire (52° N) and Warsop, Nottinghamshire (53° N) crops would fail to reach this yield on 13–53 occasions in 100. Crops established directly from seeds would fail to give this yield on more than 50 occasions in 100 at all three sites.
The effect of changes in the intestinal flow of nucleic acids on allantoin excretion in the urine of Sheep
Authors: Antoniewicz Anna M. , Heinemann W. W. , Hanks E. M. 
Published: March 2009

SUMMARYThree ewes were intraduodenally infused with yeast RNA (15, 20 and 30 g/day) or control solutions for 3 days and the net changes in urinary allantoin excretion determined. Four mature wethers fitted with a re-entrant cannula in the proximal duodenum were fed two levels (0·66 and 1 × maintenance) of pelleted lucerne hay. Allantoin excretion was compared with total nucleic acid (NA) flow in the small intestine.The average proportion of the recovery of the infused RNA-N dose as urinary allantoin–N amounted to 0·119 ± 0·0046. The values of the net increase of allantoin-N (Y, g/day) above control levels were highly significantly correlated (n= 12,r= 0·98) with amounts of RNA-N infused (X, g/day):y= 0·1185 (± 0·0086)X–0·004 (P< 0·001). The average ratio of urinary allantoin-N to NA-N passing the duodenum during 24 h was 0·173. A difference between the two conversion factors is discussed in relation to endogenous allantoin excretion and purine base composition of yeast and bacterial RNA.
The digestibility of the carbohydrate complex of barley, wheat and maize by adult fowls
Authors: Bolton W. 
Published: March 2009

1. The digestibility of the carbohydrates in barley, wheat and maize has been determined, using both conventional methods and individual methods for sugar, starch, pentosan, cellulose and lignin.2. Sugar and starch were completely digested; cellulose and lignin were indigestible and the pentosan was about one-third digested.3. Digestible pentosan accounted for about 3% of the total digestible carbohydrate.4. The ratios of the available carbohydrate, i.e. the total of sugar plus starch expressed as starch, was almost exactly the same as that of the digestible carbohydrate and could be used as a measure of the relative amounts of digestible carbohydrate in the foods.
Studies on lucerne and lucerne-grass leys III. The effect of variety of lucerne and strain of grass
Authors: Ridgman W. J. , Hanley F. , Barker M. G. 
Published: March 2009

1. An experiment comparing the growth and productivity of six varieties of lucerne representing a wide diversity of ecological conditions grown in association with S 37 Cocksfoot, S143 Cocksfoot and a commercial cocksfoot/timothy mixture is described and the results discussed.2. Variety of lucerne had a marked effect on establishment, persistence, recovery from defoliation, early spring growth, yield of total dried produce, proportion of lucerne in that produce and on yield of nitrogen.3. There was no evidence of differing degrees of compatibility of varieties of lucerne with the three strains of grass used.
Repeated backcrossing and hybrid vigour in poultry
Authors: Blyth J. S. S. 
Published: March 2009

Using two inbred lines of Brown Leghorns, B and I, a backcrossing experiment was set up to test whether inherent rate of production was a simply inherited trait. Female progeny of each generation, selected for high rate, were mated to males of the B (lower rate) line. The pullet records now available, for 2 full years' production and to 31 March in the third generation, have yielded unexpected results.In each backcross generation mean egg production has been at least as good as in the better parent, line I. This is not wholly accounted for by the behaviour of rate, since measurements of the trait in the cross approximate to the average of the two inbreds in each year. High viability and absence of very poor layers were also determining factors.Backcross egg weight remained intermediate between the widely differing parent lines, and the cross produced the greatest total weight of egg material in each set of comparisons. Body weight was also intermediate, but sexual maturity was comparable with that of line B.It was deduced that selecting the backcross breeding females for high rate had led to the retention of a greater proportion of the original I genotype than would normally have been expected, and so maintained continued heterozygosity in succeeding generations.Practical implications of the results and interpretation are discussed.
Synthetic soil conditioners
Authors: Emerson W. W. 
Published: March 2009

The ability of various high polymers to stabilize soil crumbs has been investigated using the sodium saturation technique. The soil used came from two plots on the Rothamsted classical fields, Barnfield and Hoosfield, which have received no fertilizer either organic or inorganic for 80 years, but whereas the former contains free CaCO3 the latter is acid.The polymers tested were poly vinyl alcohol, sodium alginate, a vinyl acetate-maleic acid co-polymer, polyacrylic acid and a dextran. It was necessary to add 0·2–0·5% weight of the polymers in solution to the calcareous soil to produce crumbs of maximum stability, i.e. not dispersing the distilled water. The alginate, however, was effective only if the crumbs were first sodium saturated. With the acid soil, the amount of polyvinyl alcohol necessary for maximum stability was slightly reduced, corresponding to the lower clay content of the soil, whereas only one-tenth the concentration of the maleic acid co-polymer was required. Sodium alginate had no effect on the acid soil.From the swelling pattern of the sodium-saturated crumbs in dilute salt solutions it was inferred that the non-ionic polymers, polyvinyl alcohol and the dextran form interlamellar complexes, whereas the carboxylated polymers are joined to the edge faces of the crystals. The presence of divalent cations is unnecessary for this edge linkage, as the polymers are equally effective when sodium ions only are present. It is suggested that the polymers form a series of hydrogen bonds with the exposed oxygen and hydroxyl atoms of the octahedral layer. Since these atoms have a greater tendency to co-ordinate a hydrogen ion as the pH is lowered, the carboxylated polymers would be expected to be more efficient on acid soils.A simplification of the sodium saturation technique for the evaluation of potential soil conditioners is given.