bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of leaf and flower removal on seed yield of lentil [Lens esculenta(L.)]
Authors: Pandey R. K. 
Published: March 2009

SUMMARYField studies were carried out to determine the sources of photosynthate for developing pods and to assess the effect of defoliation and flower removal at different stages on the performance of lentil. The leaves of flowering nodes were the primary source of assimilate to pods. Removal of 25–75% of leaves reduced seed yield by varying degrees depending on crop growth stage. The plants compensated for the loss of foliage to some extent, possibly through increased efficiency of the remaining leaves. One complete or 50% defoliation reduced seed yield to different extents at the vegetative, flowering, early pod formation and late pod formation stages, the greatest effect being seen at flowering and early pod formation. Plants compensated considerably by production of new leaves when defoliated at the vegetative phase. Increased moisture supply greatly enhanced the compensation ability of the lentil plants.Removal of all flowers up to 1–2 weeks after an thesis under unirrigated conditions and up to 3 weeks after anthesis in irrigated conditions did not adversely affect the seed yield. Flower removal beyond this period resulted in a significant reduction in seed yield. Little seed yield was obtained when flower removal was continued for either 6 or 8 weeks under unirrigated conditions. The plants compensated for the loss of earlier-formed flowers by setting pods from later-formed flowers. Compensation was greatly enhanced when the crop was irrigated during the reproductive phase. There was relatively little or no effect of the deflowering treatments on the number of seeds per pod or weight per seed. The flowering period of the deflowered plants was extended and their senescence was delayed. When 25% of the flowers were removed at different intervals during the reproductive phase, seed yield was not adversely affected. An increased intensity of flower removal decreased yield but the decrease was not proportional to the degree of flower removal. The plants apparently compensated by setting new pods.
The digestibility of Rhodes grass (Chloris gayana) in relation to season and proportion of the diet of sheep
Authors: Tagari H. , Ben-Ghedalia D. 
Published: March 2009

SUMMARYDigestibility trials were carried out to study the digestibility of Rhodes grass fed alone and in mixed concentrate diets. Twelve Awassi rams were used to examine the seasonal effect on the digestibility of Rhodes grass harvested at 21-day intervals.A consistent increase in the content of crude protein up to the 6th harvest was observed, being accompanied by an increase in crude protein digestibility and voluntary feed intake.In the second experiment Rhodes grass and concentrate mixed diets were examined. Sixteen Awassi rams were allocated to four diets which included 16, 32, 52 and 100% Rhodes grass. Dry-matter digestibility was found significantly different between the all-grass diet and the rest. The digestibility of crude fibre in the whole diet decreased significantly with the increase in concentrate content. The digestibility of crude fibre of Rhodes origin was calculated. It appears that the detrimental effect of concentrate on the digestibility of crude fibre of Rhodes grass origin is limited. This finding is supported by the high C2/C3 ratios in rumen liquor which were maintained up to 68% concentrate in the diet.This study indicates that Rhodes grass may serve as a highly efficient roughage component in dairy rations.
The growth and carcass composition of strains of mice selected for large and small body size
Authors: Fowler Ruth E. 
Published: March 2009

The growth and carcass composition of two strains of mice (N- andC-strain), which had both been selected for large and small body size by Falconer, have been studied.Differences in body weight between mice of theN-strain and their controls were apparent at birth and were fully maintained up to 30 weeks of age. The patterns of growth were similar in all three lines, although the large line grew at a faster rate than the small line, the controls being intermediate. Differences in absolute and relative rates of growth between the three lines reach a maximum from 21 to 35 days of age and declined thereafter.Growth in the large line of theN-strain from 14 to 40 days of age was largely due to an increase in body protein and water; after this age, increase in weight was caused mainly by fat deposition. In the small line of this strain, protein, water and fat were deposited at a more constant rate during the whole growing period. Differences in rates of growth may account for the differences in the percentage composition found between mice of the large and small lines of theN-strain at the same age.
Studies on the nutritive value of some common Egyptian feedingstuffs. II. Effect of concentrates rich in proteins on cellulose and dry-matter digestion
Authors: Akkada A. R. Abou , El-Shazly K. 
Published: March 2009

1. In a series of digestibility trials using two Rahmany ewes (see previous publication, el-Shazly, 1958), protein supplements in the form of concentrates, pure proteins or green roughage, supplying 10.16 g. N per day, did not affect significantly the digestibility of cellulose in wheat straw.2. Decorticated cottonseed cake given at three different levels, i.e. 10.16, 20.32 and 30.48 g. N, did not produce a significant change in wheat-straw cellulose digestibility.3. The digestibility of dry matter was significantly improved by all supplements used except fish meal and decorticated cottonseed cake at a level of 10.16 g. N per day.4. Total volatile fatty acids were estimated just before feeding and at different intervals after feeding.5. The implication of these results for microbial activity are discussed.
Nitrogen, sulphur and carbon uptake from some nitrogenous fertilizers using 15N, 35S and 13C as tracers
Authors: Low A. J. , Piper F. J. 
Published: March 2009

1. Pot culture experiments are described comparing the recovery of nitrogen, and sulphur by the difference and ‘labelled atom’ methods and the recovery of carbon by the latter method. Italian ryegrass was used as the test crop with ammonium sulphate, calcium nitrate and urea as the fertilizers.2. The recovery of fertilizer nitrogen was less using the ‘labelled atom’ technique than the conventional difference method.3. The recovery of sulphur from ammonium sulphate ‘labelled’ with 35S was measured. It was considerably less than the nitrogen, but not inconsiderable especially as a basal dressing of ‘unlabelled’ K2SO4 was applied.4. Using urea ‘labelled’ with 13C there was no evidence that any of the carbon was in the ryegrass four weeks after application.
The analysis of yield-density relationships in binary mixtures using inverse polynomials
Authors: Wright A. J. 
Published: March 2009

SUMMARYThe reciprocal relationship commonly used in the analysis of plant yield-density relationships in monoculture is extended to allow a similar treatment of binary mixtures, using the model:w–1a = Aa × Baapa × Babpbwhere wa is the plant weight of component a in mixture with component b, and pa and pb are the plant densities of a and b respectively. The model gives a good fit to fresh weights taken from a glasshouse experiment involving monocultures and mixtures of red clover (T. pratense L.) and Italian ryegrass (L. multiflorum L.) in different proportions, all grown at a range of plant densities. The interpretive and predictive uses of the model are discussed.
Availability of magnesium to ryegrass from soils during intensive cropping in the glasshouse
Authors: Sinclair A. H. 
Published: March 2009

SUMMARYTen Scottish soils were cropped in a glasshouse with three sowings of perennial ryegrass (Lolium perenne, cv. Dutch Barenza) without added magnesium. After 25 cuts (185 weeks) growth was poor in some soils, but soil Mg was not limiting growth in others.Uptake of Mg and the Mg concentration in the ryegrass correlated well over the entire cropping period with the equilibrium Mg-concentration ratio Mg/(Ca, Mg) = CR0, determined from the Mg quantity/intensity isotherms measured before cropping in 0·01 m chloride solutions. A CR0value of 0·16 was required in the early stages of cropping to give 0·2 % Mg in grass dry matter.Seven soils released 12–37 mg non-exchangeable Mg/kg, between one-fifth and one-third of the total Mg uptake. These reserves probably came from vermiculite minerals, but the release was too slow to maintain Mg concentrations of 0·2 % in the ryegrass.
Aspects of the water relations of spring wheat (Triticum aestivum L.) in response to induced drought
Authors: Jones H. G. 
Published: March 2009

SUMMARYThis paper describes a field study of the variation in leaf water potential (ѱL), leaf conductance (gL) and other aspects of crop water relations in a set of ten spring wheats. The two main soil moisture regimes used were irrigation and drought; the latter being imposed by placing rainwater gutters between the crop rows to intercept a proportion of any rainfall. The development of plant stresses, the changes in leaf conductances during the growing season and the relationship between these variables and soil moisture depletion are described. Mean daytime leaf water potentials declined during much of the season even in well irrigated plots. There was also evidence that stomata tended to be most open during the period just prior to anthesis. Data on variation of ѱL and gL within the crop are also presented and indicate that most evaporation occurs from the flag leaf in the spring wheat canopy.Although genotypic variation was found for the mean values of ѱL and gL, interactions between variety and water regime were generally non-significant. Although yields were not well correlated with most aspects of crop water relations measured, partly because of the dominance of other factors such as maturity and disease susceptibility, a strong negative correlation was observed between yield and gL for the period 7–14 days before anthesis.Stomatal frequencies were not related to leaf conductances and there was no evidence that the stomatal behaviour adapted to previous drought stress. The growth responses observed, however, could be regarded as adaptations for reducing evaporation. The results are discussed in relation to the breeding of drought tolerant varieties of wheat.
Field comparison of West African planting and harvesting practices in yam (Dioscorea rotundata): pre-sprouting, dry season planting, and double-harvesting
Authors: Onwueme I. C. 
Published: March 2009

SUMMARYExperiments were made to compare the practices of planting yam at the onset of the dry season (November) or at the beginning of the rains (February). Setts were also planted in February after pre-sprouting either outdoors from November/December, or indoors without water from November. Comparisons were also made between plots that were harvested first in mid-season and again at the end of the season (doubleharvesting), and plots that were harvested only at the end of the season (singleharvesting).Setts that were pre-sprouted outdoors had low percentage emergence, produced weak plants, and yielded poorly whether double-harvested or single-harvested. Setts prepared and planted in the field in November emerged over a very long time, and attained half-maximum emergence only 10–19 days earlier than setts prepared and planted in February. Whether in double-harvesting or in single-harvesting, tuber yield/sett for the November planting was significantly greater than for pre-sprouted plantings, but not greater than for the direct February planting. The first harvest of the November planting had more mature tubers and a higher percentage of marketable tubers than the others. In all treatments, single-harvesting resulted in slightly greater yield than double-harvesting, but the differences were not significant. Each second-harvest tuber from double-harvesting was more amorphous in shape, more woody, and had more eyes (buds) on it than the single-harvest tuber. It is concluded that for efficiency of land utilization, February planting is preferable to November planting, and that singleharvesting is likely to be more economical than double-harvesting.
Some effects of conservation of grass upon magnesium metabolism in sheep
Authors: Powley G. , Johnson C. L. 
Published: March 2009

SUMMARYMetabolism trials were conducted with sheep to study the effects of conservation of herbage as silage, frozen or artificially dried grass upon the magnesium and calcium availabilities in the conserved products.When the diet was changed, approximately isomagnesaemically, from hay and barley to each of the conserved products, there was a highly significant (P < 0·001) decrease in the plasma magnesium concentration. However, the plasma magnesium concentrations of the ewes eating the artificially dried grass were significantly lower (P < 0·05) than the corresponding values when they ate the frozen grass or silage. No changes were seen in the plasma calcium concentrations.The apparent availability of magnesium in the silage was significantly higher (P < 0·05) than that in the frozen and artificially dried grasses. Also, the apparent availability of magnesium and calcium was lower in the dried grass than in the other two products, whilst the retention of both magnesium and calcium was significantly lower (P < 0–05) when the dried grass was eaten as compared with the frozen grass and silage. The percentage urinary loss of magnesium was greatest on the silage and least on the dried-grass diet.It was concluded that artificially drying grass caused a reduction in magnesium availability.
Fibre medullation in Blackface lambs and hoggs
Authors: Pilkington J. M. , Purser A. F. 
Published: March 2009

A method has been described of assessing the average degree of medullation in fleece samples. This method combines information about the various fibre types and the proportion of each present in the sample, by assigning 100 fibres to classes with scores 1–5 according to the degree of medullation. A weighted mean score was determined, ten times this mean being defined as the ‘medullation index’. The index has been used for 2 years on samples taken from 2-month-old lambs and 14-month-old hoggs of the Blackface breed. Drawings of fibre types showed that the internal and external diameters and their ratio all increase with the score.The mean medullation index for the 2-month-old lambs in the 2 years was 25·6 and 24·8. The effects of sex and type of birth of lamb and age of dam were assessed by fitting constants, but their contribution to the total variance was very small. The regression of medullation on age of lamb when sampled was −0·11 units per day in both years, and was highly significant. Possible explanations for this decline of medullation are discussed.The mean medullation index for 14-month-old hoggs was 16·1 in both years. Estimate of correlation between lamb and hogg for the 2 years were + 0·45 and + 0·33. It is probable that variation in medullation within the fleece and in fibre shedding account for these low values.
Yield response of rice to root inoculation withAzospirillum
Authors: Rao V. Rajaramamohan , Nayak D. N. , Charyulu P. B. B. N. , Adhya T. K. 
Published: March 2009

SUMMARYResponse of rice to root inoculation withAzospirillumunder different N fertility levels was studied over three consecutive seasons under tropical conditions. The response toAzospirillumwas more pronounced at lower levels (30 and 45 kg N/ha) of fertilizer N than at a higher level (60 kg N/ha). Although the root inoculation withAzospirillumresulted in a significant increase in mean yields of both grain and straw especially at low levels of N (30 and 45 kg N/ha), the interaction between the N fertilizer and inoculation was not statistically significant.
Environmental temperature, energy metabolism and heat regulation in sheep. III. The metabolism and thermal exchanges of sheep with fleeces
Authors: Blaxter K. L. , Graham N. McC. , Wainman F. W. 
Published: March 2009

1. Fifteen calorimetric experiments were made with three sheep which had fleeces varying in thickness from 2·5 to 12 cm. All sheep received a constant ration, which corresponded in amount and kind to that given to closely clipped sheep in previous experiments (Graham et al. 1958).2. The metabolizable energy of the food increased with increasing environmental temperature by 2–3 Cal./24 hr./° C.3. Heat production remained constant throughout the range of 15–35° C. environmental temperature. Above 35° C. an increase occurred. At 11° C. a slight rise in heat production occurred in the sheep with a 2·5 cm. fleece. These results show that sheep with fleeces, in contrast to closely clipped sheep, have very wide thermoneutral zones.4. Heat losses by vaporization of water converged to an identical value irrespective of fleece length at 40° C. The rate of increase of vaporization with environmental temperature at lower temperatures decreased as the fleece length increased.5. Respiratory frequencies for given total watervapour losses were the same whether or not the sheep had a fleece.
Sweating in cattle. II. Cutaneous evaporative loss measured from limited areas and its relationship with skin, rectal, and air temperatures
Authors: Taneja G. C. 
Published: March 2009

1. Three female calves (Shorthorn, Zebux Australian Illawara Shorthorn, and American Brahman) of about 7–8 months old were exposed to different combinations of wet- and dry-bulb temperatures in the psychrometric chamber at the Physiology Department of the University of Queensland.2. A capsule method has been developed for measurement of cutaneous evaporation from limited areas. This method has been described in detail.3. Cutaneous evaporation from the shoulder area of the Zebu cross was significantly higher than that of the Shorthorn. There was, however, no difference between the two animals in their cutaneous evaporation from the belly area.4. In the Zebu cross the cutaneous water losses from the shoulder area, on the average, increased linearly with increase in skin temperature. In the Shorthorn, there was no important increase in the cutaneous evaporation from the shoulder area, although the skin temperature increased by about 2–3/ F.5. The Zebu cross had lower skin temperatures of the shoulder area when compared with that of the Shorthorn. These lower skin temperatures were associated with higher cutaneous evaporation.6. Increase in rectal temperature was not accompanied by increase in cutaneous evaporation in all the three animals studied.7. In all the three calves the cutaneous evaporation increased with increase in air temperature.
Preference thresholds for taste discrimination in goats
Authors: Bell F. R. 
Published: March 2009

1. The technique for assessing rejection and acceptance thresholds for gustatory sense in goats is described.2. Quinine dihydrochloride is rejected at a level of 125 mg./100 ml. and accepted at 12·5 mg./100 ml.3. Sodium chloride has a rejected threshold of 5·0 g./100 ml. and an acceptance threshold of 1·25 g./100 ml.4. Acetic acid is rejected at 5 ml/100 ml. but is accepted at 1·25 ml./100 ml.5. Glucose does not provide data for the assessment of thresholds, since all the goats consume solutions containing the highest concentration of glucose offered, viz. 40 g./100 ml.
Potentialities of producing lean meat by restricting both energy intake and water consumption of pigs
Authors: Skipitaris C. N. 
Published: March 2009

SUMMARYAn experiment was made with growing pigs, to investigate the effect of water restriction in combination with self-fed diets of reduced energy content upon carcass quality.The diets compared contained 5 and 30% of lucerne hay and the water treatments were ad libitum or progressively restricted amounts during the finishing period (60–90 kg live weight).Both increasing the proportion of lucerne meal and restricting water intake reduced significantly depth of backfat and the weight of total subcutaneous fat. There was no interaction between the treatments.The results are discussed in the light of the findings of Cunningham & Friend (1966).
Composition of body-weight change during lactation in Hereford × British Friesian cows
Authors: Trigg T. E. , Topps J. H. 
Published: March 2009

SUMMARYMeasurements were made of changes in body water, estimated by the dilution of deuterium oxide, in six Hereford x British Friesian lactating cows in their second lactation and in four of the same animals in their third lactation. The animals were subjected to a prolonged period of underfeeding followed by a period of realimentation. Milk yields were measured twice daily whilst measurement of live weight and certain blood constituents were made at 7-day intervals during the experimental periods in both years. During underfeeding milk yield differed markedly among the cows and it appeared that the cows with a higher milk potential maintained a higher yield but in doing so they incurred a greater loss of body weight. On refeeding there was little or no response in milk yield. Weight losses during the second lactation consisted mainly of body fat (calculated by difference) but the four higher yielding cows lost appreciable amounts of body water and probably significant amounts of body protein. In the third lactation all four cows lost less body fat but more body water and probably body protein than they did in the second lactation. On refeeding all animals in both years except the two lowest yielders in the second lactation gained substantial amounts of body water and probably protein but relatively little or no body fat. Significant negative and positive correlations were obtained between plasma glucose and loss of body water and between plasma free fatty acids and loss of body fat respectively.
Efficiency of nitric phosphates and Mussoorie rock phosphate in three cycles of clusterbean–wheat and groundnut–wheat rotations
Authors: Hundal H. S. , Arora B. R. , Sekhon G. S. 
Published: March 2009

SUMMARYNitric phosphates containing 80, 50 and 30% water-soluble phosphorus, and Mussoorie rock phosphate, alone or with Amjhore pyrites, farmyard manure or straw, were compared relative to concentrated superphosphate for each of three cycles of a clusterbean–wheat and a groundnut–wheat rotation. Both the field experiments were made on alkaline P-deficient Samana sands. All phosphatic fertilizers were applied to each crop at the rate of 10, 20 and 30 kg P/ha. Dry forage of clusterbean, groundnut pods and grain yield of wheat were measured. The model of concurrent straight line response was employed to calculate availability coefficient ratios which express the relative effectiveness of the different phosphatic fertilizers.Nitric phosphate containing 80 % water-soluble phosphorus and concentrated superphosphate were almost equal in their effectiveness in both 3-year rotational studies of clusterbean–wheat and groundnut–wheat. The relative efficiency of the nitric phosphates increased with the amount of water-soluble phosphorus they contained. Mussoorie rock phosphate was the least effective source of fertilizer phosphorus, although its efficiency is considerably higher for the legume clusterbean and for groundnut than for the cereal wheat. The efficiency of Mussoorie rock phosphate increased when it was mixed with the soil together with Amjhore pyrites, farmyard manure and straw respectively. These materials were more effective for clusterbean and groundnut than for wheat.