bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in faecal δ13C in response to changing proportions of legume (C3) and grass (C4) in the diet of sheep and cattle
Authors: Coates D. B. , Van Der Weide A. P. A. , Kerr J. D.
Published: March 2009

Feeding studies were conducted in 1986 with penned sheep and cattle fed legume (C3) and grass (C4) hays mixed in different proportions. Large fluctuations in diet δ13C within or between days were associated with much smaller fluctuations in the δ13C of faeces. When the overall daily legume percentage in the diet was held constant, there was little variation in the δ13C of faeces irrespective of when during the day the legume, relative to the grass, was eaten.

Cattle set stocked on Stylosanthes/grass pastures in Queensland showed only minor variations in faecal δ13C within or between days in the short term. All animals within a group showed similar trends when the diet was changing. The changes in the δ13C of faeces from day to day reflected small but real changes in diet selection.

It was concluded that the δ13C of a single faecal sample reliably reflects the integrated diet over the previous 3–4 days of a free-grazing ruminant so that the frequency and pattern of faecal sampling for estimating diet composition may be determined by considerations other than reliability
Effects of sowing a companion grass (Lolium perenne), application of grass suppressant and choice of clover variety on the growth and seed production potential of white clover
Authors: Wilman D. , Fisher A. , Marshall A. H.
Published: March 2009

The growth and seed production potential of white clover (Trifolium repens L.) was studied in field plots in 2 years, with and without a companion grass (Lolium perenne L.). Three rates of grass suppressant, fluazifop-butyl (Fusilade), applied in early June, were compared on plots sown with the companion grass. Two clover varieties, Aberystwyth SI84 and Olwen, were compared.

Sowing a companion grass reduced the amount of clover in the sward in both the first and second harvest years, but did not affect the vigour of individual clover growing points or the number of clover inflorescences when the crop was ready to be harvested for seed.

Fluazifop-butyl, at the highest rate used (125g/ha), reduced the rates of leaf emergence and extension, and the numbers of reproductive tillers, in Lolium, without reducing the rate of leaf emergence in clover, although the weight per clover leaf was somewhat reduced. In the first harvest year, the numbers of SI84 inflorescences in June and July were increased by fluazifop-butyl, but the effect had worn off by harvest (24 August). Seed yield potential was not increased by fluazifop-butyl at the rates used.

Olwen produced heavier leaves, but fewer leaves and fewer growing points/0·1 m2 than SI84. In the first harvest year, Olwen had fewer and smaller inflorescences than S184.

It proved feasible to measure the weight of new leaf produced per week and the nett additions to stolon and inflorescence dry matter (DM). The estimate of nett addition to stolon DM was increased by increasing the number of visible internodes included in the calculation, up to the maximum number recorded (nine). The rate of leaf emergence was slower on young branches than on main axes.
Genetics of seed impermeability in soya bean
Authors: Verma V. D. , Ram H. H.
Published: March 2009

Six parental cultivars (Bragg, Bragg-black seed, Kalitur, Ankur, WT-125 and Glycine formosana), 15 F1's, eight F2's and eight F3's (Bragg × WT-125, Bragg × Glycine formosana, Bragg-black seed × WT 125, Bragg-black seed × Glycine formosana, Kalitur × WT-125, Kalitur × Glycine formosana, Ankur × WT-125 and Ankur × Glycine formosana) were evaluated for seed impermeability. WT-125 and Glycine formosana were identified as impermeable types (92·18, 77·46% impermeability, respectively). The other four varieties, namely Bragg (2·93% impermeable seeds), Bragg-black seed (11·7% impermeable seeds), Kalitur (no impermeable seeds) and Ankur (0·94% impermeable seeds) had soft seed or normal seed.

The segregation pattern for impermeability in the F2 and F3 generations of eight crosses showed the involvement of a pair of dominant genes in Bragg × Glycine formosana, Bragg-black seed × WT-125, and Bragg-black seed × Glycine formosana, three pairs of dominant genes in Bragg × WT-125, Ankur × WT-125 and Ankur × Glycine formosana, and four pairs of dominant genes in Kalitur × WT-125 and Kalitur × Glycine formosana for seed impermeability, assuming maternal control as hard seed was a seed-coat phenomenon.

Vr, Wr graphical analysis also indicated that WT-125 and Glycine formosana possessed mostly the dominant genes for seed impermeability, while the remaining four cultivars contained mostly the recessive genes. The correlation coefficient of Yr (parental mean) and Vr + Wr was negative and high (— 0·907) confirming that most of the dominant genes in the parental cultivars were acting towards high seed impermeability. Thus the overall results obtained through diallel analysis of 15 F1's were in agreement with those obtained through Mendelian analysis.
Studies on the gonadal and epididymal sperm reserves of Mujjafaranagri rams
Authors: Jindal S. K.
Published: March 2009

Testicular and epididymal sperm reserves were determined in six sexually mature Mujjafaranagri rams. The testes and epididymides weight were 151·4±5·49 and 20·7±0·164 g respectively. The total spermatids/g were 78±21·8×106, while daily sperm production per ram was estimated to be 4·46×109 when corrected for tunica albuginea weight. The number of spermatozoa in the caput, corpus and cauda epididymides were 3·18, 2·56 and 16·29×lO9 respectively and they represented 14·4, 11·6 and 73·9% respectively of the sperm reserves on that side. The total epididymal sperm reserve per male ram was about 44·06×109 spermatozoa.
A study of field drain ochre deposits. 1. Abiotic chemical precipitation
Authors: Dewi I. Ap , Kelso W. I. , Johnson D. B.
Published: March 2009

It was demonstrated that abiotic chemical precipitation could account for a major proportion of iron hydroxide deposition in drainage water. In filter-sterilized (0·22 μm) drainage water samples from ochreous sites 84% of the total iron in solution was precipitated within 48 h. It was also shown that ferric hydroxide precipitates could catalyse the precipitation of ferric hydroxides in drainage water exposed to the atmosphere.
Precision drilling combining peas (Pisum sativum L.) of contrasting leaf types at varying densities
Authors: Heath M. C. , Hebblethwaite P. D.
Published: March 2009

Field experiments were conducted in 1983–4 to investigate the effect of precision drilling and plant density on establishment, growth, radiation interception and yield of combining peas of varying leaf phenotype (Varieties ‘Birte’, leafed; ‘Filby’, leafless; and ‘BS3’, semi-leafless). Precision drilling established a more uniform plant distribution than øyjord drilling; visual differences observed soon after emergence were not observed at flowering. Precision drilling resulted in more radiation interception early in the season for semi-leafless but not leafed peas; dry-matter production and photosynthetic area index (PAI) were not increased. Yield data indicated that precision drilling produced similar yields to øyjord drilling at similar densities. Increasing plant density increased radiation interception, dry-matter production and PAI during vegetative growth; density treatment effects were less marked post-flowering. Pea leaf phenotypes differed in their yield response to increasing density. Radiation interception was related to dry-matter production and PAI to obtain an estimate of photosynthetic efficiency (ε) and the attenuation coefficient (k), respectively, ε and k were constant irrespective of spatial arrangement, leaf phenotype and plant density. The relative importance of spatial arrangement and plant density in increasing radiation interception and PAI and influence on yield is discussed; other potential agronomic advantages of precision drilling are described.
Control of berry production of potato plants
Authors: Wedgwood R. B.
Published: March 2009

A trial to investigate possibilities of berry control by cultivation depth is described. Tubers planted at 10 cm produced significantly more potato plants in flower than those planted at 30 cm at the commencement of flowering. However, 3 weeks later the difference in numbers of flowers had disappeared. Emergence of overwintered tubers was about 53%, and of spring-planted tubers about 97%. Depth of planting did not affect emergence. A comparison of overwintered and spring-planted potato tubers showed earlier flowering and berry production by the overwintered tubers of about 1 week on average compared with the spring-planted tubers.

Six chemical treatments were compared at different concentrations and growth stages of potatoes and peas to assess potential control of berry production in potato volunteers growing in a vining pea crop.

Best control was found to be achieved with a combination of 4-(2-methyl-4-chlorophenoxy) butyric acid (MCPB) at 8300 mg a.i./l and Bentazone at 7300 mg a.i./l applied with the potato volunteers at full foliage to flowering stage, and before the pea crop reached the flowering bud stage, or by application of MCPB alone at 8300 mg a.i./l with the potato plants at full foliage to the pre-flowering stage. No chemical treatment either totally destroyed potato foliage, or completely suppressed potato flower and berry production, but it is argued that growers may reduce the effects considerably by careful observation and use of the appropriate chemical at the appropriate time.
Effect of contrasting tillage procedures on the emergence of onions in relation to measured physical properties of seed beds
Authors: North P. F.
Published: March 2009

A new tillage procedure was examined for the improvement in physical environment it might provide during the establishment of a vegetable crop, particularly in a dry spring. This procedure, of cultivating the soil mainly in autumn, was compared with the conventional method of cultivating in the spring on a sandy loam soil. The physical condition of seed beds prepared by the two methods was assessed by in situ measurements of soil temperature, water retention characteristics, hydraulic conductivity and surface roughness. Plant responses were compared by monitoring the emergence of onion seeds. Dry spring conditions were simulated by sheltering some plots from rain.

Final emergence, emergence time and rate of emergence were all superior following autumn cultivation for both dry and wet seed beds. The major factor affecting emergence was the coarseness of the seed bed which influenced the mechanical impedance to shoot growth. Differences in soil temperature between treatments were small, as were hydraulic conductivities under dry conditions. Preparing a seed bed in autumn rather than spring resulted in a good tilth with lower mechanical strength. This minimized the constraints on emergence when soil strength increased under dry conditions.
The effect of protein infusion on urinary excretion of purine derivatives in ruminants nourished by intragastric nutrition
Authors: Fujihara T. , Ørskov E. R. , Reeds P. J. , Kyle D. J.
Published: March 2009

Two experiments were carried out to determine endogenous excretion of purine derivatives in steers and lambs, and to investigate the relationship between microbial nucleic acid input and urinary excretion of purine nitrogen.

The endogenous excretion of allantoin after conversion of hypoxanthine, xanthine and uric acid to allantoin, was calculated to be 72 and 26 mg/kg W0·75per day in steers and lambs, respectively, when the dietary protein contained no nucleic acid nitrogen.

The excretion of purine derivatives increased linearly with increasing microbial nucleic acid input in lambs. The excretion of purine derivatives in excess of endogenous contribution was closely related to the theoretically expected values. The average recovery was calculated as 0·96 for one sheep and 1·0 for the other.
Genetic analysis of yield and yield components in field peas
Authors: Singh B. B. , Singh U. P. , Singh R. M. , Rai B.
Published: March 2009

The genetic parameters controlling the expression of seed yield and the yield components have been studied using both generation mean and triple test cross (TTC) analyses in two crosses of field pea. From generation mean analysis, it is obvious that in addition to significant estimates of additive and dominance components, epistatic components of mean [(i) and (I) types] were also important and duplicate type of epistasis was predominant for all the traits in both sets of crosses. In the TTC analysis, the major genetic component of variance was the additive component, though the dominance component was also found to be significant. There was evidence of epistasis for most of the characters studied. In fact, the overall epistasis (i type) was the major component of epistasis, but the parameter F was found in the non-significant range. The mean performance of the characters studied was higher in randomly-mated biparental progenies (BIPs) but there were more desirable transgressive segregants in the TTC population. Thus the genetic information obtained from both analyses seems to be complementary rather than alternative modes of inheritance in governing the expression of these useful economic traits.
Description and evaluation of a telemetry system for measuring body temperature in cattle
Authors: Hetzel D. J. S. , Bennett I. L. , Holmes C. R. , Encarnacao R. O. , MacKinnon M. J.
Published: March 2009

A telemetry system based on calibrated radio transmitters implanted in the right sublumbar fossa of cattle is described. It was evaluated in different situations. Rectal temperature was used as a standard measure of body temperature. Implant temperatures were on average 0·2 °C higher than rectal temperatures. The magnitude of changes in the two temperatures in response to environmental stimuli were very similar but the implants changed faster in response to heat stress, feeding and exercise. When cattle were confined in unshaded yards the repeatability (within-animal correlation) of implant temperatures measured at different times of the day was 0·41 ± 0·05, compared with 0·30 ± 0·05 for rectal temperatures. It was concluded that there was less extraneous variation associated with telemetric measurement.

The telemetry system proved effective for monitoring the body temperature of grazing cattle within a range of 300 m. The repeatabilities of individual daily maximum and minimum temperatures were 0·43 ± 0·12 and 0·43 ± 0·11 respectively. Observations confirmed that cattle in part regulate their body temperatures by behaviours such as shading, grazing and exposure to wind. Thus body temperature whilst grazing was alone not a good index of physiological heat tolerance.
Investigations into the use of indicator methods of estimating the digestibilities of feeds by ruminant animals
Authors: Sein T. , Todd J. R.
Published: March 2009

This paper describes a comparison of acid insoluble ash (AIA) and acid detergent lignin (ADL) ratio techniques for estimating digestibility with the conventional total collection method using sheep fed a range of feeds. In only two of 17 digestibility trials were the results obtained by AIA ratio techniques significantly different from those obtained by the total collection method. In the case of ADL no significant differences occurred between the results obtained by the ratio technique and total collection method.

In a trial using sheep in metabolism cages the AIA and ADL contents of faeces excreted in consecutive 4 h periods covering 48 h did not show any significant variation either within or between the two 24 h periods.

The results obtained from ‘grab’ samples of faeces (25–40 g) taken per rectum or from faeces bags attached to sheep fed communally can be expected to give acceptable agreement with total collection provided the marker concentration in the faeces represents a number of sheep sampled on several days, since variation between individual samples of faeces may be high.
Reduction in soya-bean yield after a brief exposure to nitrogen dioxide
Authors: Gupta G. , Sabaratnam S.
Published: March 2009

The most harmful of gaseous air pollutants include ozone (03), sulphur dioxide (SO2) and nitrogen dioxide (N02). These three pollutants are responsible for up to 90% of the total crop losses due to air pollution (Hecket al.1981). Reduction in crop yield is one of the most common consequences of pollutant-crop interaction (Koziol & Whatley, 1984; Treshow, 1984). Mean yields of four soya-bean cultivars, York, Dare, Cutler and Clark, grown in open-top chambers with non-filtered air, were reduced by 20% compared with those grown in carbon-filtered air (Kohutet al.1982). The major components affected were number of pods, number of seeds per filled pod and weight of seeds; a linear reduction in seed weight per plant was reported with increasing concentration of O3.
Minimizing volatilization and leaching losses of nitrogen by different nitrogen carriers in Japanese mint (Mentha arvensisL.)
Authors: Ram Muni , Chatterjee B. N. , Yadav R. L. , Singh D. V.
Published: March 2009

Japanese mint, an important essential-oil-bearing crop, is cultivated for menthol used in cosmetic and pharmaceutical industries. It requires a high level of nitrogen fertilizer, between 150 and 250 kg N/ha depending on the agro-climatic conditions (Ghosh & Chatterjee, 1976; Yadav, Mohan & Ram, 1983). During the crop cycle (January–August), frequent irrigations and high intensive rains result in poor N recovery especially on light-textured soils. With a view to reduce losses of N and improve N recoveries, the relative efficiency of neem-cake-coated urea, laccoated urea and urea supergranules has been investigated in comparison with prilled urea in Japanese mint.
Phosphorus and calcium metabolism in growing calves with special emphasis on phosphorus homoeostasis: 1. Studies of the effect of changes in the dietary phosphorus intake on phosphorus and calcium metabolism
Authors: Challa J. , Braithwaite G. D.
Published: March 2009

Calves were fed continuously at 4 h intervals a low P basal diet with or without P supplementation to give three levels of dietary P intake: one was deficient in P (2·5 g/day), the second adequate (6·0 g/day) and the third contained an excess of P (10·0 g/ day) according to Agricultural Research Council (1980) recommendations. Once steadystate conditions were achieved (after 2–3 weeks on the diet)32P and46Ca kinetic studies were carried out, together with measurements of P flow rates at the reticulorumen and P and Ca balances. With increased dietary P intake, the amount of dietary P absorbed increased as initially did the efficiency of P absorption. Both the serum P concentration and the rate of P retention increased in direct relation to increased P intake and increased P absorption. Salivary secretion of P increased with increased P absorption and in direct relation to serum P concentration. Endogenous faecal losses of P were also directly related to P intake and P absorption and results suggest that increased loss with increased P intake is inevitable.

Despite a constant and adequate Ca intake, the rate and efficiency of Ca absorption, which was low on the low-P diet, increased significantly on the adequate and high-P diets. Similarly, Ca retention increased substantially on the higher P diets, showing that Ca metabolism can be controlled according to P status.
The performance of Ongole heifers grazing native and introduced pasture species at Sumba, Indonesia
Authors: Rudolf I. G. W. , Blair G. , Orchard P. W. , Til A. R. , Hunt M.
Published: March 2009

An experiment was conducted to examine the effect of fertilizer (triple superphosphate) and stocking rate on animal and pasture productivity on Sumba Island, Eastern Indonesia. The Ongole heifers used in the 1-year experiment gained weight during the wet season and lost weight during the dry season at stocking rates of 0·5 and 1·0 head/ha when grazing nativeThemedapasture. The dryseason weight loss was arrested when a prepared seed-bed pasture, which contained 21 % Siratro at the start of the experiment was grazed at a stocking rate of 1·5 head/ha. Increasing the stocking rate to 2·5 head/ha on this pasture resulted in an increase, in the weed component of the pasture from 12 to 84% in 1 year.

The mineral content of plucked samples of pasture indicated that levels of Ca and Mg were generally adequate for growing beef cattle and that Na supplementation would be beneficial. Plant N concentration was below 1·5% in theThemedaandImperatacomponent but above this in the legume at the prepared seed-bed site. The P concentration in theThemedaandImperatawas always below the 0·24 % level required by cattle, as it was in the legume at the end of the experiment.

The introduction of herbaceous legumes into pastures under set stocking conditions can lead to pasture instability.
Effects of native vesicular–arbuscular mycorrhizal fungi and phosphate fertilizer on red clover growth in acid soils
Authors: Sainz Maria J. , Arines J.
Published: March 2009

The effect of P applications and native vesicular-arbuscular mycorrhiza (VAM) on the growth and P nutrition of red clover plants was studied in two acid hill soils with similar edaphic characteristics.

Mycorrhizal and non-mycorrhizal plants were compared under sterilized soil conditions. Plant growth increased on P addition in both soils, but the effect of mycorrhiza in improving drymatter production and P uptake was significant only in one of the soils. Fourteen and twenty-five mg/kg Olsen-P were needed in this soil to obtain the same yields by mycorrhizal and non-mycorrhizal plants, respectively. Results are explained in terms of a different effectiveness of the two fungal populations, and the possible effect of the soil sterilization process on percentage VAM infection is discussed.
Yield stability of selected forage vetches (Vicia spp.) under rainfed conditions in west Asia
Authors: Moneim A. M. Abd El , Cocks P. S. , Swedan Y.
Published: March 2009

With the current high prices for livestock, forage legumes are increasingly attractive to farmers in west Asia. There has been very little genetic improvement of the main species, of which three vetches, Vicia saliva (common vetch), V. villosa subsp. dasycarpa (woollypod vetch), and V. narbonensis (Narbon vetch), show promise. As a first step in genetic improvement 23 genotypes of common vetch and one each of woollypod vetch and Narbon vetch were grown at four sites in Syria and one in Lebanon over three seasons. Since local climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment, to give 15 environments in all. genotype × environment (G × E) interactions were analysed using linear regression.

There was considerable variation in herbage and seed yields within both genotypes and environments, and G × E interactions were highly significant. In the case of herbage yield good environments could be defined as those receiving high rainfall and low incidence of frost. Several genotypes appeared to possess wide adaptation, in terms of both yield and stability. Climate, except for late spring rains, had little effect on seed yield, nor were any of the genotypes widely adapted. However, in the broad sense heritability was much higher for seed than for herbage yield.

There is a need to define good and bad environments for seed yield. Based on observations during the study it is likely that good environments for Narbon vetch are those where broomrape (Orobanche crenata) is absent, while root-knot nematode (Meloidogyne artiella) may affect seed yield of common vetch. In view of its high seed yield the possible role of Narbon vetch as a grain legume is briefly discussed.
Distribution of14carbon-labelled assimilates in flowering plants of oilseed rape (Brassica napusL.)
Authors: Keiller D. R. , Morgan D. G.
Published: March 2009

A study has been made of the distribution of14carbon-labelled assimilates in flowering oilseed rape plants. Up to 10 days after anthesis individual flowers were strong sinks for assimilates for 2 days after opening but thereafter became weak sinks for a period of 24 h. This period coincided with pollination and subsequent fertilization. After fertilization the young pods again became strong sinks. Between 13 and 16 days after anthesis other flower buds, flowers and young pods which had previously been strong sinks failed to attract assimilates and aborted. This fall in sink capacity occurred at about the same time on all branches and appeared to be co-ordinated on a whole-plant basis.
The effect of plant raising and cultural factors on the curd initiation and maturity characteristics of summer/autumn cauliflower crops
Authors: Wurr D. C. E. , Elphinstone E. D. , Fellows Jane R.
Published: March 2009

Experiments were conducted in 1986 and 1987 to determine the influences of plant raising temperature, transplant age, N top-dressing and irrigation regime on the curd initiation and maturity characteristics of the cauliflower variety White Fox. The prime objective of this work was to determine whether changes in crop production practice had an influence on the period between curd initiation and maturity, in order to aid the development of techniques predicting when curds will reach a specific size.

The duration of the period from curd initiation to curd maturity was not significantly affected by any treatment in either year and treatment effects on curd size at maturity were of no practical importance provided that the recommended level of N top-dressing was achieved. It is therefore concluded that changes in production practices within the normal commercial range are unlikely to have any significant practical effect on the use of techniques to predict the timing of crop maturity.

There were large differences between the experiments in the mean number of leaves formed at curd initiation, which ranged from 22·0 to 36·7. In order to interpret these data a relative vernalization stimulus was calculated from 12 leaves onwards. It had a maximum rate of vernalization between 5 and 17 °C and a reduced rate at lower and higher temperatures and adequately accounted for the differences in the number of leaves at curd initiation.
An approach to the determination of rumen degradability of nitrogen in low-grade roughages and partition of nitrogen therein
Authors: Negi S. S. , Singh B. , Makkar H. P. S.
Published: March 2009

Rumen degradability of dry matter (D.M.) and N in wheat straw, rice straw and local grass hay, containing 5·16, 6·37 and 4·58 mg N/g D.M. respectively, was estimated by rumen fermentation measurements at 3, 6, 9, 12, 24 and 48 h using the nylon bag technique. The degradability of D.M. at an assumed rumen outflow rate of 0·025/h was 21·7, 34·9 and 22·4 for wheat straw, rice straw and grass hay, respectively. Theestimation of degradability of N was confounded by thedeposition of ruminal microbial nitrogen in the nylon bag. A correction was made by measuring the accumulation of N when N·free fibre and cellulose were incubated in the nylon bags. The effective degradability of N in the roughages at the assumed rumen outflow rate was 54·5, 36·9 and 42·8% respectively, showing that the roughages contain rumen-degradable N for microbial nutrition. The undegradable nitrogen (UDN) values in wheat straw, rice straw and grass hay were 2·35, 4·02 and 2·62 mg/g D.M., and after correction for unavailable acid detergent-linked N, the available UDN values were 0·58, 2·95 and 1·32 mg/g D.M., respectively.
Response of soya bean (Glycine max (L.) Merr.) to phosphorus, potassium and molybdenum applications
Authors: Pal U. R. , Olufajo O. O. , Nnadi L. A. , Singh L.
Published: March 2009

Field experiments during the wet seasons of 1981–1985 determined the response of soya bean to the application of P, K and Mo at four locations in the Nigerian savanna. Soya bean was grown at factorial combinations of four rates of P (0, 13·2, 26·4 and 396 kg P/ha) and two rates of K. (0 or 41·5 kg K/ha) in 1981, but in subsequent years two or three rates of Mo (0, 0·5 or 1·0 kg ammonium molybdate/ha) were included in a randomized complete block design with three replications at all locations.

Significant yield increases due to the application of P were recorded in 10 out of 11 trials. Yield increases due to 13·2 or 26·4 kg P/ha were from 29 to 210% over the control. The effects of K and Mo application were not significant in 10 out of 11 trials and eight out of nine trials, respectively. Whereas P x Mo interaction effects were significant in three trials only, highest yields were recorded due to application of 26·4 or 39·6 kg P/ha in combination with 0·5 kg ammonium molybdate/ha.

Application of P increased the percentage of P in soya-bean leaves significantly and a range of 0·275–0·330% P appears to be the critical nutrient range of P in soya-bean leaves at full bloom stage. Application of K had no effect on K concentration in leaves.
Inheritance and breeding significance of two floral morphological traits in cowpea (Vigna unguiculata)
Authors: Emebiri L. C.
Published: March 2009

Variations in floral morphology have been observed by most breeders involved in cowpea (Vigna unguiculata (L.) Walpers) improvement. Usually, the most successful pod set is achieved following hand pollination when plants with large flowers are used as female parents because these are easy to manipulate. In breeding work involving wide crosses, unconscious selection of female parents on the basis of flower size could lead to correlated changes in pod and seed characteristics which may or may not be desirable. This would depend on the heritability of flower size and its correlation with the pod and seed characteristics.
Effects of chlormequat application on stem characteristics, yield and panicle conformation of winter oats
Authors: Leitch M. H. , Hayes J. D.
Published: March 2009

The responses to treatment with chlormequat of winter oats at various rates of applied N were investigated in field experiments over two seasons. Chlormequat, applied at crop growth stage (GS) 32, significantly reduced stem length by an overall average of 25·3% in 1985/86 and 27·4% in 1986/87. The percentage reduction was not significantly influenced by variety or by the rate of N applied. All intcrnodes apart from the basal one were significantly shortened. The third internode from the base showed the largest percentage reduction and the uppermost internode the largest actual reduction in length, in all three varieties. Stem shortening was always associated with an increase in the weight per unit length of stem. In 1985/86 lodging in untreated control plots became more severe as N rate increased, but was completely controlled by the application of chlormequat at all but the highest rate (150 kg N/ha).

Combine-harvested grain yields of the variety Pennal in 1985/86 and of Bulwark and Pcnnal in 1986/87 were reduced where chlormequat had been applied. Hand-harvested samples from these treatments did not show the same reductions in yield, but revealed a significant increase in the number of grains per panicle and a significant reduction in their mean individual weight. The grain characteristics of Peniarth were unaffected.

The lengths of the main-stem panicles and primary branches in the panicle were shortened as a result of chlormequat application. In addition, the degree of branching and the number of spikelets were increased in the lower third of the panicle but reduced in the upper two thirds. In both Bulwark and Pennal the numbers of sterile grains were increased by the application of chlormequat and, in Bulwark only, the number of fertile grains was reduced. In Peniarth the numbers of fertile and sterile grains were unaffected.
Effect of thin layer drying rate and swath architecture on the rate of grass swath drying under controlled conditions
Authors: Lamond W. J. , Spencer H. B. , Graham R. , Moore A. B.
Published: March 2009

A total of 51 grass swaths was dried in a wind tunnel under controlled conditions of temperature and humidity. The swath treatments covered a range of conditioning treatments, crop types, maturities and porosities. Drying rates of the swaths were related to crop and swath properties to establish which variables were important in influencing the overall drying rates of the swaths. Multiple regression analysis was used to assess the statistical dependence of drying rate on variables reflecting crop and swath properties: the dependence on swath structure was approximately four times greater than the dependence on crop conditioning. Improved swath drying rates could be achieved by lesssophisticated machinery than the current mower conditioners.
Photoperiodic control of breeding activity in the Southdown ewe with particular reference to the effects of an equatorial light regime
Authors: Thwaites C. J.
Published: March 2009

1. Oestrous activity was studied in three groups of eight Southdown ewes exposed respectively to natural lighting (30½° S.), accentuated reversed seasonal lighting, and equatorial lighting for a period of 2 years.

2. Control ewes exhibited a restricted breeding season confined to the autumn and winter months of each year. The breeding season averaged 102–5 days in length and during it the ewes experienced an average of 7·14 ± 0·47 oestrous periods.

3. The natural breeding season was almost completely reversed by artificial reversal of the normal seasonal variation in daylength. This constitutes presumptive evidence that daylength is the major factor controlling seasonality of oestrus in Southdown ewes.
Change of skeletal dimensions during growth in sheep: the effect of nutrition
Authors: Searle T. W. , Graham N. McC. , Donnelly J. B.
Published: March 2009

Measurements of skeletal size were made at 2–3-month intervals on 30 Border Leicester × Merino castrate male (wether) sheep between 2 and 27 months of age. Fifteen sheep were fed ad libitum on a high-quality diet and the other 15 half the average amount consumed by the first group, age for age. The ad libitum group grew faster and were larger in all body dimensions on each occasion, except for leg length at 27 months which showed no statistical difference between groups. When the groups were compared over the live-weight range common to both (16–44 kg) the unrationed animals were consistently wider at the shoulders but smaller in leg and chest dimensions.

The relationship between each body component and age is described by a Mitscherlich equation and the relationship with live weight by a linear equation in which both variables are log transformed. Separate relationships were determined for each sheep and tested for differences within and between groups.
Glomerular filtration rate and blood and urinary urea concentrations in Barmer goats of the Rajas than desert
Authors: Khan M. S. , Sasidharan T. O. , Ghosh P. K.
Published: March 2009

Khan, Ghosh & Sasidharan (1978a) and Khan, Sasidharan & Ghosh (1978b) have reported on Barmer goats' efficiency in water economy under the conditions of the Rajasthan desert, India. Some earlier reports also pointed to the superiority of dosert-adapted goats of other breeds in this respect (Maloiy & Taylor, 1971; Shkolnik, Borut & Choshniak, 1972; Dawson et al. 1975). Recently, Khan, Sasidharan & Ghosh (1978 c) have recorded evidence which indicates that Banner goats' management of the body's water balance is decidedly superior to that of desert sheep. However, just as these two species exhibit wide divergence in their behavioural responses to environmental stresses, they appear to exhibit physiological responses of different types in combating such stresses. In the present note, information on a few important indices of adaptation to water insufficiency conditions, namely, glomerular nitration rate (GFR) and blood and urinary urea concentrations in Barmer goats are presented.
Genotypic and phenotypic variances and correlations in field beans (Vicia fabaL.)
Authors: Yassin T. E.
Published: March 2009

Estimates of genotypic and phenotypic variances and covariances were determined for yield and yield components in ten field beans varieties grown at two locations over three seasons.

Substantial amounts of genotypic variance were obtained for yield/plot, 1000-seed weight and number of pods/plant. Variability in number of seeds/pod and much of the variation in yield/plant was attributable to environmental effects and their interaction with the varieties. Seed yield/plot was closely and positively correlated with number of pods/plant and yield/plant, while it was closely and negatively correlated with 1000-seed weight.

The implications of these correlations for selection are discussed.
Sources of magnesium for grassland
Authors: McIntosh S. , Crooks P. , Simpson K.
Published: March 2009

In a 3-year field experiment, calcined magnesite, Epsom salt, magnesium ammonium phosphate and magnesian limestone gave only small and non-significant increases in yield of a mixed sward but increased the concentration of magnesium in the herbage at all 11 cuts. Magnesianlimestone increased plant magnesium concentrations less than calcined magnesite, magnesium ammonium phosphate or Epsom salt, all of which had a similar effect; each increment of calcined magnesite gave additional increases in magnesium concentration.

Concentration of magnesium in the plant dry matter increased as each season progressed and was linearly related to exchangeable magnesium. At an exchangeable soil magnesium of 1·4 m-equiv./100g soil, Mg concentrations doubled between the first and last cuts. Changes in magnesium concentrations caused by increasing the exchangeable soil magnesium from 0·7 to 1·4 m-equiv./100g soil were less than the seasonal effects.
Effect of dense, stratified sandy soil on crop roots
Authors: Worker G. F. , Ayers R. S. , Karah M. A. , Thomason R. E.
Published: March 2009

A study was conducted to determine root development in a stratified and mixed sandy soil in the Sahara sands of Libya. Lucerne (Medicaqo sativa L.), millet (Pennisetum typhoides Burn.)> wheat (Triticum activumL.), grain sorghum (Sorghum bicolor L.), and several other crops were grown on soil that varied in depth to the stratified layers. Root depth and growth were measured by excavating along a representative root at intervals until the crop was mature or until no further root penetration into the subsoil occurred.

Trial plantings showed that none of the root systems of the plants tested could penetrate the stratified layers to any important extent, even with the application of adequate water and fertilizer, although all the layers were sufficiently porous to allow surplus water to drain through them freely. However, a few roots of lucerne, sudangrass, grain sorghum, and millet penetrated 2—3 cm into these layers, and many roots, especially of lucerne, grew into any natural cracks that occurred in these layers. If the compacted layer was loosened by cultivation, all the crops tested rooted normally in the loosened zone.
Metabolic and endocrine responses of pregnant and lactating ewes to intravenous glucose or insulin
Authors: Bassett J. M.
Published: March 2009

To investigate whether late pregnancy results in increased resistance to insulin action in ewes, a group of 18 crossbred ewes (six with twin foetuses) were given intravenous injections of glucose (0·25 g/kg) and insulin (0·25 U/kg) about 18days before full term and again during lactation, about 36 days after delivery. Before the injections, basal plasma concentrations of glucose, free fatty acids and growth hormone were lower during pregnancy than during lactation, but insulin concentrations were similar on the two occasions and cortisol concentrations were higher during pregnancy.

Rates of glucose removal and insulin secretory responses to the glucose injection were similar on the two occasions, both in ewes with single lambs and in those with twins. Insulin injection also resulted in similar decreases in glucose concentration on the two occasions in all ewes. Recovery from hypoglycaemia was somewhat delayed during pregnancy whencompared with lactation, but less so than in wether sheep given a similar injection of insulin. The plasma free fatty acid concentration decreased more slowly after glucose injection during pregnancy than in lactation. Responses of plasma cortisol concentration toinsulin-induced hypoglycaemia were similar on the 2 days, but plasma growth hormone concentration increased far more in lactating ewes after both injections.

The results did not indicate increased antagonism to insulin action in ewes during late pregnancy, but did show that changes in the counter-regulatory hormones after the disturbances to glucose homeostasis may differ markedly in the two situations and suggest that hyper-responsiveness of the system regulating growth hormone secretion contributes to the increased plasma growth hormone concentration observed in lactating animals.
Concentrations of blood constituents from 12 to 72 weeks of age in genetically high and low milk production lines of Friesian and Jersey cattle
Authors: Gibson J. P. , Wiener G. , Field A. C.
Published: March 2009

Blood samples were collected at 12-week intervals from 12 to 72 weeks from a total of 221 growing Friesian and Jersey calves and assayed for plasma concentrations of free fatty acids (FFA), ketones, glucose, calcium, phosphorus, magnesium, copper, albumin and globulin. Sixty-six of the animals could be allocated to genetically high and 73 to genetically low milk producing lines on the basis of being sired by the ‘best’ or ‘worst’ nationally available progeny tested sires. All animals were housed indoors and fed a complete pelleted diet ad libitum. There were no differences between genetically high and low milk production lines for any blood constituent and no useful indicators of genetic merit for milk production in later life. There were no differences between breeds for metabolites related to energy status (FFA, ketones, glucose). Friesians bad higher magnesium and lower mean copper concentrations than Jerseys and had higher phosphorus concentrations up to 36 weeks. Differences between breeds and ages in mineral concentrations were not related to breed differences in the discrepancy between observed intakes and predicted requirements of minerals. Concentrations of globulins were higher and of albumin lower in Jerseys than in Friesians at 12 and 24 weeks possibly owing to slightly higher disease incidence of Jerseys in early life. There were changes with age in concentrations of all constituents except FFA. There was evidence of genetic variation within breeds and lines for mean plasma concentrations of ketones, copper and globulin. There was no evidence for differences between females and castrates for any blood constituent.
Dispersal of Pyrenopeziza brassicae spores from an oil-seed rape crop
Authors: McCartney H. A. , Lacey M. E. , Rawlinson C. J.
Published: March 2009

Spores of Pyrenopeziza brassicae, which are mostly dispersed by rain splash, were trapped 4 m above and 20 m downwind of an oil-seed rape crop. This suggests that not all trapped spores were transported in ballistic splash droplets (100–2000 μm); indeed some were airborne during periods of dry weather following closely after rain. Vertical and horizontal spore concentration gradients corresponded to the gradients expected for spores with fall speeds of between 2 and 5 cm/sec. Atmospheric dispersal calculations suggest that such spores have the potential for transport over considerable distances to other susceptible crops.
Effect of cultivar, carbofuran and row spacing on the incidence of stem and leaf nematodes (Ditylenchus dipsaci and Aphelenchoides ritzema-bosi) in lucerne (Medicago sativa) and on lucerne herbage yield
Authors: Whitehead A. G.
Published: March 2009

In a clay loam at Rothamsted, inoculated with lucerne stem nematode (Ditylenchus dipsaci) and a leaf nematode (Aphelenchoides ritzema-bosi), lucerne herbage yields were increased on average by 17 and 59% respectively, in the first and second years of a 4-year experiment (1988–91), by carbofuran granules applied around the seeds at sowing in spring 1988. In seven-row plots over the 4 years of the experiment, 1·65 kg a.i./ha increased total yield as much as did 3·3 kg a.i./ha (11 and 12%, respectively). In four-row plots over the same period, 1·9 kg a.i./ha increased total yield by 9%. The cultivars Euver and Vertus, which are partially resistant to D. dipsaci, yielded 44·3 and 48·5 t dry matter/ha, respectively, whereas Europe and Vela, which are susceptible to the nematode, yielded less (36·3 and 28·6 t/ha, respectively). When sown in summer 1990 in four-row plots, cultivars Europe and Euver yielded larger crops in 1991 in plots given 1·2 or 2·3 kg a.i. carbofuran/ha in 1990 (on average 34 and 48%, respectively) than in untreated plots. As little as 0·6 kg carbofuran/ha increased the yield of cv. Europe in infested soil.

The stunting of lucerne plants, associated with D. dipsaci infestation, was greatly decreased by carbofuran, which prevented infestation of the first crop by D. dipsaci and A. ritzema-bosi. Stem nematode infestation of lucerne plots was adequately and quickly assessed by measuring the lengths of rows stunted by D. dipsaci. Other methods of assessment were laborious and no more reliable.
Use of para-amino hippuric acid to measure blood flows through portal-drained-viscera, liver and hindquarters in sheep
Authors: Ortigues I. , Durand D. , Lefaivre J.
Published: March 2009

The objectives of this study were (i) to evaluate a new surgical procedure to catheterize hepatic vessels as well as the posterior aorta and vena cava, (ii) to test a modification of a downstream dilution technique in order to measure blood flows through splanchnic tissues and hindquarters in rapid succession, and (iii) to improve the reliability of splanchnic blood flow measurements using paraamino hippuric acid (PAH). Ten adult ewes were used. The transhepatic surgical approach used proved successful; it was relatively easy to set up and a good recovery of hepatic functions was obtained. The attempt to measure splanchnic and hindquarters blood flow in rapid succession by alternating the sites of PAH infusion was unsuccessful, probably because of transient modifications in infusion rates due to different blood pressures in veins and arteries. Indeed, arterial PAH concentrations changed with infusion site. Finally, a better reproducibility of splanchnic blood flow measurements was obtained in sheep, fed every 3 h, by infusing the required amount of PAH partly via the mesenteric vein and partly via a ruminal vein.