bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on Calcium Cyanamide. I. The Decomposition of Calcium Cyanamide in the Soil and its Effects on Germination, Nitrification and Soil Reaction (With Eight Text-figures.)
Authors: Crowther E. M. , Richardson H. L. 
Published: March 2009

1. The work described in the present series of papers was undertaken with the object of ascertaining the best conditions for the use of calcium cyanamide and of comparing it against older nitrogenous fertilisers. Earlier work has in part been repeated so as to ascertain whether the recent improvements in manufacture have overcome the difficulties encountered with the pre-War product.2. The decomposition of cyanamide to urea can be brought about by a number of minerals likely to occur in the coarser fractions of the soil. The decomposition of cyanamide by soil proceeds according to a logarithmic law such that the rate of disappearance is proportional to the concentration of cyanamide in the soil water.
Oestrous behaviour in Bunaji (White Fulani) heifers
Authors: Johnson A. O. , Gambo A. 
Published: March 2009

SUMMARYContinuous observations were maintained on a group of 32 White Fulani (Bunaji) heifers at three periods daily, 06.00–12.00 h, 14.00–18.00 h and 18.00–22.00 h, for 112 days, during which time all heifers were recorded for incidence of standing for mounts for a while by a vasectomized bull but for the whole period by other heifers in the group as well as soliciting for mounts. Thirty heifers were judged as showing oestrus. Of the 62 oestrous cycles recorded, 82·2% had mean length (±S.E.) of 22·4 ± 0·7 days. Average duration of oestrus (±S. E.) in 30 heifers was 3·1±0·2 h. There were no significant differences between the three observation periods for the time spent in mounting activities, the duration cf oestrus commenced at the three periods and for the average oestrous periods.It would appear that closer observation for indicative oestrus between 06.00 and 18.00 h should be valuable for the purpose of oestrus detection in an artificial insemination scheme under the Guinea Savanna condition of Nigeria.
Digestible cell wall and undigested cellular contents of two grasses of low net energy value for growing cattle
Authors: Moir K. W. 
Published: March 2009

SUMMARYIn two grasses of low net energy value for growth and fattening of cattle, digestible cell-wall values were close to 40% of forage organic matter (OM), similar to the expected value for grass. A value of 14% of forage OM for apparently undigested cellular contents in both grasses was just outside the range of values for grass. The data supported previous evidence that total cell wall is the only value that can be used at present to define grass in terms of its digestible dry matter.
Some effects of canopy height on perennial ryegrass and white clover in a field sward
Authors: Wilman D. , Shrestha S. K. 
Published: March 2009

SUMMARYEight canopy heights, maintained by weekly cutting, were compared during summer and early autumn on a perennial ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward.Perennial ryegrass adapted to a taller canopy by increasing the length of its leaf blades much more than it increased the length of its leaf sheaths, and by increasing the length of its blades proportionately more than their width. White clover adapted by increasing the length of its petioles much more than it increased the length of its leaflets. Canopy height did not affect the number of ryegrass leaves emerging or dying per tiller or the number of live, emerged leaves maintained by a tiller. The amount of herbage harvested at the weekly cuts was largely unaffected by canopy height once the swards had adapted to the particular management. Leaf blades in the taller canopies, therefore, lost a much lower proportion of their length to defoliation than those in the shorter canopies. Consequently, the length of blade dying per tiller per week was more strikingly affected by canopy height than was the rate of leaf extension. The increasing amount of material lost by death with increasing canopy height was confirmed by the weights of senescent and dead tissue collected weekly from a fixed area in each plot. Herbage in the lower compared with the upper layers of the taller canopies was much less digestible and lower in N content.
The response of Italian ryegrass to nitrogenous fertilizer at different times of year, with particular reference to residual effects
Authors: Wilman D. , Ojuederie B. M. 
Published: March 2009

SummaryThe 32 combinations of applying or not applying nitrogenous fertilizer on five dates, with 6-week intervals between dates, during one treatment year were compared in three field experiments with Italian ryegrass (Lolium mvltiflorum). Phosphorus (P)and potassium (K) were applied at a uniform, high rate to all plots. All plots were harvested, by cutting, five times during the treatment year and once in May of the subsequent year.Dry-matter yields and dry-matter yield responses to N were lower at the September and October harvests than at the May, June and July harvests. Where no N was applied 6 weeks before a harvest, N applied 12 weeks before that harvest generally increased yields of dry matter, N, P and K. On the other hand, where N was applied 6 weeks before a harvest, N applied 12 weeks before that harvest tended not to increase dry-matter yield and tended to reduce P and K yields. Applying 420 kg N/ha/year compared with nil approximately trebled the amounts of dry matter, P and K harvested in the treatment year. At the May harvest in the subsequent year dry-matter yield was increased by N applied in the treatment year, for all five application dates, although the previous autumn there had been no positive residual effect of the early applications. Apparent recovery of N was low compared with that recorded with Italian ryegrass in Cambridge. The content of N, as well as P and K, in herbage in May was reduced by the application of N the previous year. In the 1972 experiment the proportion of ‘stem’ in the harvested produce was markedly increased by N application. The size of this effect may have been associated with the rather small amount of soil N available. Applied N increased the number of tillers in the sward, but this effect appeared to be rather short-lived. A major reason for the positive effect of applied N on dry-matter yield, including the positive residual effect, appeared to be the increase in leaf blade length and probably sheath length due to N.
Developmental consequences of two-row and six-row ear type in spring barley: 2. Shoot apex, leaf and tiller development
Authors: Kirby E. J. M. , Riggs T. J. 
Published: March 2009

SummaryLeaf and tiller production, ear development and ear growth were measured on a two-row and a six-row spring barley genotype, on the F1 between them and on the first backcrosses.Among the developmental differences between the parental genotypes the following appeared to be of particular significance: the two-row genotype bore more leaves on the main shoot than the six-row genotype and these were initiated more slowly, but emerged more rapidly; the two-row genotype had a proportionately longer ear initiation phase than the six-row; the apical dome was bigger in the six-row than in t he tworow; the two-row genotype produced more tillers.The association of characteristics with ear type may depend on a pleiotropic effect of the ear type (V – v) locus or, alternatively, some of these characteristics may be under independent genetic control. The latter hypothesis was supported by the developmental pattern of the F1.It may be that well-adapted two-row and six-row genotypes have patterns of development balanced for the particular ear type. Hybridization between ear types may disrupt these balanced developmental patterns producing a high frequency of poorly adapted genotypes in the progeny.
Cold tolerance and winter hardiness in Lolium perenne: II. Influence of light and temperature during growth and hardening
Authors: Lawrence T. , Cooper J. P. , Breese E. L. 
Published: March 2009

SummaryIn the first paper of this series it was shown that Lolium perenne material required hardening periods involving low, but above freezing, temperatures before frost tolerance was achieved. The present experiments show that the light conditions during the hardening and prehardening periods are also important. At both stages a reduction in total light energy reduced subsequent cold tolerance but the relative effects of light intensity and photoperiod differed between the prehardening and hardening treatments. Thus low light input during the hardening period at 2 CC reduced cold tolerance most when given at higher intensities over shorter days (8 h) while during the prehardening growing period at 20 °C the reduction was greatest when the lower light input was given at low intensity over longer days (16 h).Varieties of different climatic origins reacted differentially to the treatments. The Mediterranean variety Fano was particularly adversely affected by low light intensities during hardening and also benefited from higher temperatures during the prehardening growing period. With higher light intensities and higher growth temperatures this Mediterranean variety approached the more northern material in cold tolerance; but as a corollary it was clear that the N. European variety Veja was able to harden under lower light conditions, and lower growing temperatures. The varieties Melle and S. 321 from intermediate latitudes, were intermediate in response.Although water soluble carbohydrate content was increased during the hardening period, except at the lowest light intensity (2·9 W/m2), no simple relationship between the WSC content and the cold tolerance of the different varieties could be detected.The results provide a useful guide to the pre-treatments necessary to discriminate between varieties for cold tolerance in such a way that the results can be correlated with field performance.
The efficiency of some experimental designs used in dairy husbandry experiments
Authors: Taylor W. B. , Armstrong P. J. 
Published: March 2009

Records for milk, fat, solids-not-fat and fat percentage over forty-eight complete lactations were used as uniformity data to determine the relative efficiencies of a variety of experimental designs used in dairy husbandry experiments.In general, it was found that:1. Experiments conducted during the earlier part of the lactation are more efficient than those conducted during the later part.2. Three-weekly periods are generally more efficient than 5-weekly periods.3. If 3-weekly periods are used, then extending the time of the experiment over four such periods instead of three reduces the error. The converse is the case with 5-weekly periods since the experiment is carried over into the highly variable later part of the lactation.4. Grouping the animals according to the yields recorded during the first 40 days of lactation does not appear to reduce the error.An analysis of covariance using the pro-experimental records of the performance of the animals has been carried out on ordinary group trials and it is hoped to publish the results at a later date, but investigations on the data have shown that both reversal and Latin square designs are more efficient than ordinary group trials even when such an analysis is performed.
The lamb's tail in relation to wool type in British breeds and crosses of sheep
Authors: Bhattacharya P. , Hammond John 
Published: March 2009

1. Lambs' tails at about a month old have been collected from two or three flocks of several different British breeds and crosses of sheep, and have been classified into ten grades according to the relative amounts of wool or hair extending from base to tip of the tail.2. In general the relative amounts of wool and hair found on the tail of the lamb in the different breeds correspond with the quality of the wool of the adult fleeces of the breeds.3. Considerable variability in tail grade was found between different individuals in the same flock, so that there is scope for selection in this respect to improve the quality of the wool especially on the britch.4. It is suggested that as differences are more obvious on the tail at birth than in the adult fleece, selection for uniformity of fleece might be made at this time.
Effect of giving water intermittently on excretion patterns of water and certain electrolytes in Ghokla sheep during summer
Authors: More T. , Sahni K. L. 
Published: March 2009

SummaryExternal balances of water, sodium and potassium were examined in carpet wool Chokla sheep given water once in 24, 48 and 72 h during the hot months. There was a significant decline (P < 0·01) in feed intake on the third day of dehydration. The water intake of this group approached 30% of body weight and there was also a significant (P < 0·05) decrease in urine volume after 2 days of water deprivation. There was a large balance for potassium in all treatments and most especially when the sheep were given water every 72 h. It is argued that this unusually high balance of potassium was probably a characteristic of sheep adapted to a hot climate.
A relationship between amino acid supplementation of the diet of pigs and the metabolism of N and energy
Authors: Frape D. L. , Tuck Mary G. 
Published: March 2009

SummaryTwo experiments with growing pigs showed that the addition of L-lysine hydrochloride to diets limiting in lysine content raised not only N retention but also true N digestibility as a percentage of the diet. The change achieved in amino acid balance had no consistent effect upon ED (digestible energy, kJ/g diet) and therefore the experiment did not support the hypothesis that non-linear changes in dietary ED, resulting from ingredient substitutions, could be attributed to associated changes in amino acid balance.
Breed and sex effects on the development and proportions of muscle, fat and bone in pigs
Authors: Fortin A. , Wood J. D. , Whelehan O. P. 
Published: March 2009

SummaryThe development and proportions of muscle, fat and bone were studied in 341 entire male and female Iron Age (European Wild Pig × Tamworth), Pietrain and Large White pigs ranging in live weight from 12 to 370 kg. The number of pigs was: Large White, 138 entire males and 112 females; Pietrain, 41 entire males and 31 females; Iron Age, eight entire males and 11 females. The breeds and sexes were compared in terms of the allometric growth coefficients of tissues (b) and of tissue weights at constant side weight and constant weight of total side bone.At the geometric mean for side weight (26·5 kg), Pietrain carcasses had the most muscle (16 kg), followed by Large White (15kg) and Iron Age (11 kg), but the least fat (6 kg). Large White and Iron Age carcasses had 7 and 12 kg of fat, respectively. Relative to side weight, the earliest maturing tissue, bone, was particularly slow growing in Iron Age pigs (b = 0·627) and relatively fast growing in Large Whites (b = 0·801). The opposite was true for fat, the latest maturing tissue, and consequently Iron Age (b = 1·345) and Large White (b = 1·164) pigs were identified as early and late maturing, respectively. Pietrains had a higher growth coefficient for fat relative to side weight (b = 1·249) and lower growth coefficient for bone (b = 0·713) than Large Whites. The difference in percentage fat between Pietrains and Large Whites decreased slightly between 65 and 120 kg live weight. In terms of tissue growth patterns, Pietrains therefore demonstrated early maturing characteristics compared with Large Whites, and it is possible that a low voluntary feed intake under ad libitum feeding conditions prevents them from expressing these characteristics in terms of percentage of fat in the side. Pietrains had a particularly high muscle:bone ratio (6·2 at the mean side weight) compared with Large White (5·2) and Iron Age pigs (5·3).The difference in carcass composition between entire males and females was breeddependent. Entire male carcasses were slightly leaner overall and had a lower muscle: bone ratio than those of females, but tissue allometric growth patterns were similar in the two sexes.
Soluble and slow-release nitrogen fertilizer effects on grass forage, as influenced by rate and placement
Authors: Allen S. E. , Terman G. L. , Hunt C. M. 
Published: March 2009

SUMMARYSoluble ammonium nitrate (AN) and urea were compared with slow-release oxamide and sulphur-coated urea (SCU) as N sources for clipped annual ryegrass (Lolium multiflorum) or common bermuda grass (Cynodon dactylon) in four greenhouse experiments. Mixed and surface applications of a wide range of N rates were evaluated for 9 to 14 cuttings of grass forage. Both granular oxamide and SCU exhibited slow-release N properties, especially when surface-applied. Uptake distribution of N with high application rates of AN and urea tended to resemble that with the slow-release sources. Slow-release properties of oxamide and SCU were accentuated at high application rates. Lower N recovery from surface-applied urea than from AN indicated volatilization loss of urea N. Volatilization loss also occurred with oxamide, but low N recovery from oxamide and SCU resulted largely from incomplete dissolution of the granules during the 18- to 34-week experimental periods. Very low N recovery was obtained from urea formaldehyde having an activity index of 42.
The effect of interval between harvests and nitrogen application on the proportion and yield of crop fractions in four ryegrass varieties in the first harvest year
Authors: Wilman D. , Droushiotis D. , Koocheki A. , Lwoga A. B. , Shim J. S. 
Published: March 2009

SUMMARYThe effect of six intervals between harvests and three levels of N application on the proportion and yield of green leaf, dead leaf, ‘stem’ and inflorescence was studied in four ryegrass (Lolium) varieties during a 30-week period in the first harvest year in a field experiment. In one variety, S.23, the ‘stem’ was divided into true stem, leaf sheath, unemerged leaf and unemerged inflorescence.There was a bigger yield of ‘stem’ and a bigger total herbage yield response to doubling the interval between harvests in S.321 and S.22 than in S.23 and S.24.In the absence, but not generally in the presence, of applied N, S.321 outyielded the other varieties. S.24 was particularly responsive to applied N, especially in terms of green leaf yield.There was a large positive effect on yield of doubling the interval (from 3, 4 or 5 weeks to 6, 8 or 10 weeks respectively) during the main period of stem development. During the subsequent period, however, doubling the interval produced very little extra yield of total herbage and reduced green leaf yield substantially.The percentage increase in yield due to the application of N progressively decreased as the interval was increased.Maximum net production of green leaf was obtained by harvesting every 4 or 5 weeks for most of the season, extending to 6 weeks at the end. Harvesting every 3 weeks, by comparison, resulted in a slightly lower annual green leaf yield, but with a distinctly higher proportion of green leaf in the crop.Applied N generally had little effect on the proportion of crop fractions, but reduced the proportion of green leaf and increased that of' stem' in S.23 and S.24 at the August and September harvests.
Growth and yield of sugarcane and potato in companion cropping system
Authors: Verma R. S. , Yadav R. L. 
Published: March 2009

SUMMARYTwo potato genotypes, Kufri Sindhuri (KS) and Kufri Chandramukhi (KC), were grown in association with sugarcane (cv. Co 1148) at 1:1 (SP) and 1:2 (SPP) sugarcane (S): potato (P)row arrangements. Growth behaviour and yield of both crops in companionship were compared with those of their sole cropping. Initially, KC accumulated more dry matter in tubers than KS. At harvest, the contribution of tubers to total dry matter was the same in both genotypes. However, KS produced significantly higher absolute tuber yields than KC. Potato row arrangements in sugarcane did not significantly affect the proportion of dry matter in different plant components. However, SPP gave significantly higher tuber yields than SP and was the same as with sole potatoes. Drymatter accumulation, canopy development and yield of sugarcane were not affected significantly by potato row arrangements in the companion cropping system. Sugarcane was unaffected by KC in companion cropping but KS exerted an adverse effect on all the growth characters and yield of sugarcane. Similarly, in sequential cropping, sugarcane yielded significantly less when planted after KS than after KC.
Effects of fungicides, applied in autumn, and a growth regulator, applied in spring, on the growth and yield of winter barley grown on contrasting soil types
Authors: Jenkyn J. F. , Gutteridge R. J. , Todd A. D. 
Published: March 2009

SUMMARYExperiments in 1985 and 1986, at Woburn Experimental Farm in Bedfordshire, tested the effects of fungicides, applied in autumn, and a growth regulator, applied at GS3O–31 or GS32–33 in spring, on winter barley grown on two contrasting soil types in each year. Leaf diseases did not become severe in any of the experiments but take-all (Gaeumannomyces graminis var. tritici) was prevalent in 1985. Triadimenol (‘Baytan’) was more effective than flutriafol (‘Ferrax’) in decreasing the severity of takeall and its activity against the disease was related to earliness of sowing.Mean responses in grain yield to the fungicide treatments were mostly small and not significant but did not conflict with the hypothesis that crops on lighter soils benefit more from autumn fungicides than those on heavier soils. Mean effects of the growth regulator sprays were also small but they interacted with both soil type and season. Over the 2 years the later spray applied to crops on the heavier soil gave the largest mean response. Sprays applied to crops on lighter soils were often detrimental to yield, especially in 1985.
Effects of sample preparation on nitrogen degradability of pangola grass (Digitaria decumbens) and tropical tree legumes
Authors: Aumont G. , Saminadin G. , Cerneau P. , Xandé A. 
Published: March 2009

SummaryThe effects of particle size on the nitrogen degradability of four tropical forages were studied in 1991 in Guadeloupe. Samples of pangola grass (Digitaria decumbens) 22 and 47 days old, Gliricidia sepium and Leucaena leucocephala were prepared as follows: grasses were (1) freshly cut with scissors to 0·5–1·0 cm in length and frozen at – 18 °C; or for later study were dried at 80 °C and ground to pass a (2) 0·5 mm, (3) 10 mm or (4) 20 mm screen. Nitrogen degradability (ND) was determined by placing samples in nylon bags with two different pore sizes (25 and 46 μm) which were then put into the rumen of cows for 2, 4, 8, 16, 24 and 48 h. The kinetics of nitrogen degradation were examined using Ørskov's model. Particle losses through the nylon bags, dry matter (DM) and nitrogen solubility of the samples were also measured in vitro. The sample preparation and the type of forage were the main sources of variation in the rapidly degradable nitrogen fraction, the slowly degradable nitrogen fraction, the degradation rate, the potentially degradable nitrogen fraction and ND. Nitrogen degradability was 55·8,46·7, 640 and 46·5% for pangola grass (at 22 and 47 days regrowth), Gliricidia and Leucaena samples, respectively. Mean ND was 47·9, 59·4, 56·1 and 49·6% for freshly cut and 0·5, 1·0 and 2·0 mm dried ground samples, respectively. Sample preparation had little effect on nitrogen solubility. For samples dried and ground at 0·5 and 1·0 mm, particle losses were 18·8 and 15·0% of DM, respectively. The insoluble but degradable fraction was 60·8, 51·9, 42·5 and 42·7% for freshly cut and 0·5, 1·0 and 2·0 mm dried ground samples, respectively. The freshly cut material appeared to be suitable for the estimation of ND in tropical forages.