bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors affecting growth and yield of winter oilseed rape (Brassica napus), 1985–89
Authors: Leach J. E. , Darby R. J. , Williams I. H. , Fitt B. D. L. , Rawlinson C. J. 
Published: March 2009

SUMMARYEffects of agronomic factors on yield of winter oilseed rape were examined in multifactorial experiments, with a single-low (low erucic acid, high glucosinolate) cultivar (Bienvenu) in 1984/85 to 1987/88 and a double-low (low erucic acid, low glucosinolate) cultivar (Ariana) in 1986/87 to 1988/89. Establishment of September-sown plots was better than that of August-sown plots in 1984, 1987 and 1988, but not in 1985 when September was very dry. The total dry matter (DM) (kg/ha) of August-sown plots was much greater than that of September-sown plots throughout autumn and winter but by harvest the plant DM of late-sown plots was slightly greater. Combine-harvested yields of late-sown plots were greater than those of early-sown plots in 1984/85 (cv. Bienvenu) but not in 1988/89 (cv. Ariana); effects of sowing date on yields were smaller in other seasons, although late-sown plots generally had larger yields. Insecticide treatments increased combine-harvested yields in 1987/88 (cv. Bienvenu) and 1988/89 (cv. Ariana) and increased hand-harvested yields in 1984/85, by increasing the number of plants/m2. Fungicide spray treatments increased yields in all years except 1989, by increasing 1000-seed weights. Application of growth regulator sprays increased yields in 1986/87 to 1988/89; effects on cv. Ariana were associated with increased numbers of pods/plant. There were no consistent effects of spring nitrogen rates or timing on yield or yield components.
Breed differences in response of wool growth to annual nutritional and climatic cycles
Authors: Doney J. M. 
Published: March 2009

Nine Cheviot and nine ¾ Merino, ¼ Cheviot sheep were fed at similar annual maintenance levels. The annual ration was provided in three ways–in simulation of the ‘natural’ intake cycle, the reversed intake cycle or as a constant daily ration. Liveweight curves for both breeds corresponded fairly closely with the feed intake curves but considerable genotype/environment interaction was found in the response of unscoured wool growth to variation in feed intake.After an extended period of adjustment, the between sheep variation in intake, in the Merino group, was reflected in variation in wool-growth rate at all times. In the Cheviot group, intake and wool growth were related in summer but not in winter. It is suggested that not only is the efficiency of wool growth subject to genetic control but that the modification of efficiency in response to variation in environmentally controlled metabolic processes is also a function of the genetic background.
The sodium and potassium content of some grass genera, species and varieties
Authors: ap Griffith G. , Walters R. J. K. 
Published: March 2009

Data from one field and three glasshouse experiments are presented on the sodium and potassium contents of a number of grasses and on the effect of nitrogen, potassium, and sodium supply on these.Large and consistent differences in sodium content exist between different genera of grasses. Potassium content may also show such differences.Environmental factors which affect sodium content are the supply of nitrogen and potassium. Increasing nitrogen in the growth medium raises the sodium content, increasing potassium lowers it.A grass with a potentially high sodium content will show a wide range in this element depending on the environment. One with a low sodium potential will remain always low, not unaffected by environment but affected within a more restricted range.
The value of liquid digested sewage sludge. II. Experiments on rye-grass in South-east England, comparing sludge with fertilizers supplying equivalent nitrogen, phosphorus, potassium and water
Authors: Coker E. G. 
Published: March 2009

In a factorial trial comparing liquid digested sludge with equivalent water, and inorganic nitrogen, phosphorus, and potassium fertilizers, almost all the effects observed could be attributed to the uptake of nitrogen or potassium.Over the 2-year period of treatment application, liquid digested sludge and equivalent inorganic fertilizer nitrogen and potassium gave similar responses of 22.3 and 23.8 lb. dry matter per lb. of nitrogen, and 59 lb./acre K increased the response to inorganic nitrogen alone by 5.4 lb./lb. of nitrogen.Over the 2-year period of treatment the amount of potassium absorbed by herbage, in excess of that applied, was greater with fertilizer nitrogen than with liquid digested sludge. Added potassium had no direct effect on crude protein production. Liquid digested sludge and inorganic nitrogen fertilizer increased crude protein to a similar extent.
The regrowth of swards of S24 perennial rye-grass subjected to different pretreatments
Authors: Davies Alison 
Published: March 2009

In an experiment in which plots of S24 perennial rye-grass grown at a 2 in. spacing were subjected to pretreatments involving two different nitrogen levels and three different cutting frequencies it was found that subsequent regrowth was most strongly related to total stubble weight. Other significant correlations were obtained with root weight, tiller number and weight of water-soluble carbohydrates in roots and stubble.The relationships between cultural treatments and sward condition, and between sward condition and regrowth are discussed in the light of the results from this and other experiments.
Nitrogen mineralization, nitrate leaching and crop growth after ploughing-in leguminous and non-leguminous grain crop residues
Authors: Francis G. S. , Haynes R. J. , Williams P. H. 
Published: March 2009

SummaryA field experiment was conducted in Canterbury, New Zealand to investigate the effect of six leguminous and non-leguminous grain crops on soil N fertility over a 12 month period (March 1989 to March 1990). All crops had an overall negative N balance during their growing season. A greater amount of soil N was removed by barley, rape and lupins (104–119 kg N/ha) than by field beans, field peas or lentils (50–74 kg N/ha).Net N mineralization was measured in all treatments between residue incorporation and the start of winter. With the exception of the lupins, accumulation of mineral N in the soil profile before the start of winter drainage was greater following leguminous (mean 124 kg N/ha) than non-leguminous crops (mean 80 kg N/ha).Cumulative apparent leaching losses over the autumn/winter were largely a reflection of the mineral N content of the profile before the start of drainage. Excluding lupins, leaching losses declined in the order fallow > legumes > non-legumes (110 > 72 > 37 kg N/ha respectively). The anomalous results for the lupins were attributed to the incorporation of a large amount of woody residues after harvest which may well have resulted in extensive net N mineralization occurring later in the autumn.Over a 12 month period, all treatments showed a decline in N fertility (110–160 kg N/ha), although compared with barley, the total loss of soil N was 10–40 kg N/ha less following leguminous crops.Growth of the following spring wheat test crop was affected by the preceding crop. Grain yield, grain N yield and total N yield were significantly related to the mineral N content of the soil at the end of leaching, and to a measure of net N mineralization during the growing season of the test crop.
Influence of sucrose supplementation on nitrogen kinetics and energy metabolism in sheep fed with lucerne hay cubes
Authors: Obara Y. , Fuse H. , Terada F. , Shibata M. , Kawabata A. , Sutoh M. , Hodate K. , Matsumoto M. 
Published: March 2009

SummaryThe effects of sucrose supplementation on nitrogen kinetics and energy metabolism were examined in sheep fed lucerne hay cubes using a15N isotope dilution method and balance and respiration trials in Tsukuba, Japan in 1988. Sheep were fed lucerne hay cubes (1183 g DM/day), with or without 204 g/day sucrose, at 2 h intervals from continuous feeders. Supplementation with sucrose decreased urinary N excretion (P< 0·01), resulting in an increase in N retention from – 1·1 to + 2·0 g N/day (P< 0·01). Supplementation with sucrose resulted in no change in faeces and methane energy, a decrease in urinary energy (P< 0·01) and an increase in heat production and energy balance (P< 0·01). Sucrose supplementation also resulted in lower rumen ammonia (P< 0·05) and plasma urea concentrations (P< 0·05) and reduced urinary urea excretion (P< 0·01). The fermentation of sucrose in the rumen resulted in a decrease in rumen pH (P< 0·01) and in the acetate: propionate ratio (P< 0·05). Sucrose supplementation increased the proportion of urea transferred to the rumen (P< 0·05), non-ammonia N (NAN) concentration in the rumen (P< 0·001) and NAN flow from the rumen to the lower digestive tract (P< 0·001). Urinary allantoin excretion rate increased with sucrose supplementation (P< 0·05). The plasma glucose concentration was unchanged but plasma insulin concentration was increased with sucrose supplementation (P< 0·05). The influence of energy-rich supplements, such as sucrose, on N kinetics and the mechanism of the increase in N retention with sucrose supplementation are discussed.
Comparative productivity and drought response of semi-tropical hybrids and open-pollinated varieties of sorghum
Authors: Blum A. , Golan G. , Mayer J. , Sinmena B. , Obilana T. 
Published: March 2009

SUMMARYWhile the relative advantage of hybrids over open-pollinated varieties has long been established for temperate sorghums in developed countries, similar information for semi-tropical sorghums used in Africa and India is relatively scant, especially under conditions of drought stress. This study compared 23 hybrids with 21 open-pollinated varieties, all developed in India and/or Southern Africa. Materials were field-tested under conditions of stored soil moisture at two levels of drought stress (dryland or one supplemental irrigation) at Bet Dagan, Israel in 1989.Irrespective of the water regime, grain yield and harvest index increased and leaf area index decreased with a shorter growth duration of the genotypes. Hybrids were earlier, had a larger leaf area index, more than double the harvest index and produced more grain compared with varieties. In spite of their longer growth duration, varieties were less water-stressed than hybrids, as judged by their midday leaf water potential, relative water content and the extent of leaf rolling. The relatively poor plant water status of the hybrids could be partly ascribed to their larger leaf area index. Hybrids produced more biomass per day than varieties under low stress while varieties produced more biomass per day than hybrids under high stress. Thus, in terms of plant water status and mean daily biomass production, varieties were more drought resistant than hybrids. However, the physiological superiority of the varieties under drought stress did not result in a higher grain yield because of their inherent relatively poor harvest index, typical of the tall and late African sorghums. The superior physiological resistance to drought stress of these varieties could be translated into a yield advantage under drought stress if their potential harvest index is improved.
Yellow rust (Puccinia striiformisWestend.) of barley in England, 1960–65
Authors: Macer R. C. F. , Driessche M. Van Den 
Published: March 2009

Yellow rust of barley has been observed more frequently at Cambridge in the period 1960-65 than the previous five years. The disease occurs in most parts of England but appears to be prevalent and more damaging in the south and west of the country. The increased incidence of the disease is probably associated both with the greatly increased acreage of barley now being grown and with the introduction of more susceptible barley varieties.Two isolates ofPuccinia striiformisdiffering in virulence characteristics have been found to be representative of the population of the pathogen in England. These isolates are similar to, if not identical with, physiologic races 23 and 24 which are widespread in continental Europe.A survey of the seedling resistance toP. striiformisof the currently cultivated barley varieties showed that, of the twelve varieties tested, nine were susceptible to both isolates of the pathogen and three were susceptible to one isolate and resistant to the other. No varieties were resistant to both isolates.
Analysis of maize–common bean intercrops in semi-arid Kenya
Authors: Pilbeam C. J. , Okalebo J. R. , Simmonds L. P. , Gathua K. W. 
Published: March 2009

SummaryMaize (Zea mays L.) and common bean (Phaseolus vulgaris L.) were each sown at four plant densities, including zero, in a bivariate factorial design at Kiboko Rangeland Research Station, Kenya during the long and short rains of 1990. The design gave nine intercrops with different proportions of maize and beans, and six sole crops, three of maize and three of beans. Seed yields in both the sole crops were not significantly affected by plant density, so the mean yield was used to calculate the Land Equivalent Ratio (LER), which averaged 1·09 in the long rains but only 0·87 in the short rains. These low values were apparently due to the fact that beans failed to nodulate and fix nitrogen in the study area. The difference in LER between seasons was probably caused by differences in the amount and distribution of rain in relation to crop growth. Maize was more competitive than bean, each maize plant being equivalent to between 0·7 and 3·4 bean plants depending upon the treatment and the season.
Response of late-sown mustard (Brassica juncea) to irrigation and nitrogen
Authors: Yadav S. K. , Chander Krishan , Singh D. P. 
Published: March 2009

SummaryThe response of late-sown mustard (Brassica juncea L.) to four rates of irrigation (ratio of irrigation depth to cumulative pan evaporation, ID:CPE = 0·2, 0·4, 0·6 and 0·8) and nitrogen (0, 30, 60 and 90 kg/ha) was investigated at Haryana Agricultural University, India, in the winter seasons of 1986/87 and 1987/88. Increases in the amounts of water and N fertilizer applied increased leaf water potential, stomatal conductance, light absorption, leaf area index, seed yield and evapotranspiration and decreased canopy temperature. Water-use efficiency was highest for the 0·4 ID:CPE irrigation treatment in both seasons, and for the 60 kg N/ha N treatment in 1986/87 and the 90 kg N/ha treatment in 1987/88. The combination of 0·6 ID:CPE with 60 kg N/ha gave a significantly higher seed yield than lower rates and equalled that from the highest irrigation and N treatment combinations. The amount of water used by the mustard crop decreased with increasing soil depth irrespective of treatment. In the deeper soil layers, the percentage of total moisture use was greater under less irrigated than under more frequently irrigated plots. Leaf area index showed a significant positive linear relationship with evapotranspiration and light absorption and a negative linear relationship with canopy temperature. Seed yield was linearly related to leaf area index and light absorption coefficient.
Growth and light interception in field bean (Vicia faba) infected by Ascochyta fabae
Authors: Madeira A. C. , Clark J. A. , Rossall S. 
Published: March 2009

SummaryThe effects of inoculation by Ascochyta fabae Speg. on growth and light interception in field bean (Vicia faba L.) were studied. Measurements were made in a field trial using cv. Ticol, a cultivar vulnerable to this disease during early vegetative growth and at the beginning of the flowering stage. Infection reduced leaf area duration, light interception and dry matter yield of energy (light use efficiency) and, consequently, the dry matter production of the crop. Reductions in seed yield ranged from 12 to 30% compared with a prophylactic fungicide treatment.
Potential rates of denitrification in two field soils in southern England
Authors: Iqbal M. M. 
Published: March 2009

SUMMARYPotential rates of denitrification from two field soils, differing in past history, were measured by anaerobic incubation of fresh samples in a glasshouse maintained at 15–25 °C at ARC Letcombe Laboratory, Wantage, Oxfordshire in 1981. Nitrate was not limiting. The topsoils (0–20 cm) from both sites denitrified more than the subsoils (20–60 cm). The production of nitrous oxide was positively correlated with the carbon content of the soils while potential rates of denitrification in the two soils were similar. The total accumulated loss of nitrogen was greater from the soil with the greater organic carbon content. The use of acetylene showed that the denitrification losses were underestimated by measuring only nitrous oxide. N2O was still being reduced to N2 even after 100 h continuous exposure to acetylene.
Some factors affecting apparent nitrogen digestibility of roughage diets fed to cattle
Authors: Moran J. B. , Vercoe J. E. 
Published: March 2009

SUMMARYPublished and unpublished results for apparent nitrogen digestibility from 107 digestibility trials with Zebu (Africander, Brahman and their crosses with British cattle) and British breeds of cattle were analysed by regression analyses to determine its relationship with dry matter intake and dietary nitrogen content.The linear regression of apparent nitrogen digestibility on the reciprocal of dietary nitrogen content was an adequate mathematical description of the relation (r = 0·92) and the addition of the reciprocal of nitrogen intake as an independent variable improved the description (r = 0·95) particularly for diets with a low nitrogen content. Both these equations have a physiological basis.Estimates of the true nitrogen digestibility and metabolic faecal nitrogen from the linear regression of apparent nitrogen digestibility on the reciprocal of dietary nitrogen content were 86·8% and 0·49 g/100 g dry-matter intake. Independent estimates of these parameters from a multiple regression of total faecal nitrogen on dry-matter intake and nitrogen intake were 88·7% and 0·46 g/100 g dry-matter intake. The analyses on the breeds suggested that the Zebu cattle may have a higher true digestibility and a lower metabolic faecal nitrogen than the British cattle, although the differences were small and could not be subjected to statistical tests.
Effect of inoculation and nitrogen fertilization on nodulation, seed yield and quality of soya beans
Authors: Abu-Shakra S. , Bassiri A. 
Published: March 2009

SUMMARYSoya beans grown on land planted the previous year with inoculated soya beans produced more nodules, lodging, seed yield, 1000 seed weight, and protein content and less seed oil concentration as compared to those grown on land that was planted with non-inoculated soya beans. Nitrogen fertilization (120kg N/ha) reduced the total number of nodules per plant. Increasing inoculation rates of the seed increased the dry weight of nodules per plant. Location, nitrogen fertilization, and inoculation increased or decreased the levels of certain amino acids but had no significant effect on the sulphur amino acids, cystine and methionine.
Culture and fertilization of sheep ovarian oocytes I. Effect of culture medium on resumption of meiosis
Authors: Quirke J. F. , Gordon I. 
Published: March 2009

SUMMARYOocyte recovery was conducted in 329 slaughtered sheep; from 3072 vesicular follicles ruptured, 1210 oocytes were obtained (av. 3·7 per sheep). After recovery or culture in various media, 801 oocytes were examined for developmental stages. In cattle follicular fluid, little evidence of resumption of meiosis was found. In sheep follicular fluid, meiosis was resumed in many oocytes, but was arrested at the pro-metaphase to metaphase-I stage. A high proportion of oocytes matured to metaphase-II when cultured in growth medium.
Ovine ill-thrift in Nova Scotia:I. The possible regulation of the rumen flora in sheep by the fungal flora of permanent pasture
Authors: Brewer D. , Calder F. W. , MacIntyre T. M. , Taylor A. 
Published: March 2009

SUMMARYThe growth of ewe lambs of the Shropshire breed declined and in some cases ceased at the end of July, when they grazed permanent pastures at the Experimental Farm, Nappan, Nova Scotia. This decline in growth coincided with a decrease of about three orders of magnitude in the numbers of viable rumen bacteria. At the end of July an increase of one to two orders of magnitude was observed in the numbers of viable fungi collected from the pastures. Lambs grazing pastures developed from tidal marsh of the Bay of Fundy had a better growth performance than lambs grazing adjacent pastures developed from mixed conifer-deciduous forest. The forest soils supported a greater fungal population than the marshland soil, and several species were found predominantly on the forest soil.
Milk production in Awassi and Hungarian Merino sheep in Iraq
Authors: Karam H. A. , Juma K. H. , Al-Shabibi M. , Eliya J. , Al-Ma'ali H. N. Abu 
Published: March 2009

SUMMARYOn the Abu-Ghraib Experiment Station, milk production was investigated in 31 Awassi ewes of different ages and 12 newly imported Hungarian Merino ewes, two years old, together with the effect of age, lactation period, number of lambs born and reared and stage of lactation on milk production in the Awassi ewes. The relationships between milk production, birth weight and weaning weight of lambs were also investigated.First-lactation milk yield during the suckling period (90 days) based on 12 h milking interval was 114·58 kg in the Merino and 75·29 kg in the Awassi.Age had no significant effect on milk production in Awassi ewes although first-lactation yield was lower than that from subsequent lactations. Ewes that produced and nursed twins gave significantly more milk than ewes that produced and nursed single lambs.Milk yield in Merino and Awassi ewes increased with the decrease of milking interval from 12 to 4 h. The correlation coefficients between milk yield during 12 and 4 h were positive and significant.Correlation coefficients between birth and weaning weights and milk production were positive in both breeds. The correlation coefficient between weaning weight and milk production was 0·78 in the Awassi (P <0·01) and 0·65 in the Merino (P <0·05). The multiple correlation coefficient between weaning weight and birth weight and milk production was 0·67 in the Awassi and 0·43 in the Merino.
An evaluation of the field performance of the progeny of plants regenerated from embryos of Hordeum vulgare cv. Golden Promise
Authors: Dunwell J. M. , Cornish M. , Powell W. , Borrino E. M. 
Published: March 2009

SUMMARYThe study was designed to compare the agronomic performance of progenies of barley plants (cv. Golden Promise) regenerated from immature zygotic embryos (IE) with these originating from embryos produced after chromosome elimination (Hordeum bulbosum technique). Conventionally derived seed material was used as control.In a randomized complete block design with two replicates, plants were scored for mildew reaction (Erysiphe graminis f.sp. hordei), number of days to awn emergence, height and yield. Data showed no evidence of variation for mildew reaction and although significant differences between lines for the other three characters were observed in the IE-derived sample these were not significantly greater than that observed in the control samples.