bluuebunny/crossref_metadata_2025 huggingface dataset:
Biochemistry of water-logged soils: Part II. The presence of a deaminase in water-logged soils and its rôle in the production of ammonia
Authors: Subrahmanyan V.
Published: March 2009

(1) The ammonia formed in water-logged soils was present mostly in the soil sediment. The surface water contained only a very small portion of the total amount produced.

(2) Added ammonia was in a similar manner retained mostly in the soil itself. It could not be leached out by extraction with water nor volatilised with increase of temperature. There is evidence to show that the ammonia exists in the soil as an exchangeable base.

(3) On allowing the soils to dry out the ammonia disappeared rapidly and corresponding amounts of nitrates were formed. Very little ammonia was lost by volatilisation.

(4) The production of ammonia took place even in presence of volatile antiseptics. The reaction was shown to be brought about by a deaminase.

(5) Studies with a number of proteins and ammo acids showed that only very simple amino compounds (glycine aspartic acid and asparagine) were deaminised. Witte's peptone, which contains amino acids, was also attacked.

(6) An active preparation of enzyme was extracted from the soil with an aqueous solution of glycerin saturated with toluene.

(7) Significant deaminising action was shown by the enzymes from cultures of the mixed microflora of the soils.

(8) By acting on amino bodies that are otherwise resistant to biological action the deaminase probably helps to release readily available plant food. Its action should be of great importance in tropical swamp soils.
The proteins of green forage plants: III. The proteins of forage plants of the natural order Cruciferae (genus Brassica). Comparison with colzalin, a globulin from rapeseed
Authors: Davies W. L.
Published: March 2009

In a previous paper (Davies, 1926) the author studied the differences in the compositions of protoplasmic proteins of plants within a Natural Order (Leguminosae). The Natural Order Cruciferae afforded a means of developing the study in the direction not only of ascertaining differences, if any, of protoplasmic protein of plants within a genus, but also of differences possible within a species. Thus proteins were studied from the following varieties of the cabbage species (Brassica oleracea L.): Cabbage (B. oleracea var. capitata), Marrow stem kale (B. oleracea var.) from the stems and leaves separately, Kohl rabi (B. oleracea var. caulorapa). Also, the proteins from the leaves and roots respectively of white turnips (B. napo-brassica) were isolated and studied. In order to compare the protoplasmic proteins with those of seed of a plant of the same species, a globulin from rapeseed (seed of Brassica Napus L.) was prepared and analysed.
Studies onBacillus amylobacter, A. M. et Bredemann
Authors: Cunningham Andrew , Jenkins Hermima
Published: March 2009

(1) An aerobic coccus has been obtained from cultures of the motile butyric acid bacillus under conditions which exclude the possibility of contamination.

(2) Descriptions of the coccus and the bacillus are given.

(3) The coccus does not fix nitrogen in soil extract containing dextrose.
Studies in mineral metabolism: IV. Determination of phosphorus compounds in blood by dry combustion
Authors: Green H. H.
Published: March 2009

Determination of the phosphorus partition in blood is described, combining dry combustion with the ceruleo-molybdate procedure of Deniges. Advantages in speed and convenience are claimed over the conventional Briggs methods.
Studies in mineral metabolism: V. Composition of bovine blood on phosphorus deficient pasture
Authors: Malan A. I. , Green H. H. , du Toit P. J.
Published: March 2009

Data are recorded concerning the phosphorus partition of the blood of cattle grazing over phosphorus deficient pasture of the Union of South Africa. The outstanding characteristic is low inorganic phosphorus, with a correlated reduction in total phosphorus.

When a small ration of bone meal is given to the cattle, comparatively normal figures are shown. Heifers approaching two years in age, supplied with bone meal from weaning onwards, show a normal inorganic P fraction of 5 mg. per 100 c.c. of blood. Control heifers without bone meal show 2·3 mg., or less than half. Control cows may drop to 1 mg., or even lower. Calves of control mothers are normal so long as milk supply is adequate, but may show reduced inorganic P if aphosphorosis of the mother is acute. In general, low inorganic P in the blood is associated, with poor condition of the animal. Rapid colorimetric determination of inorganic P in the blood of the grazing animal, easily obtained from the jugular vein, provides a simple means of detecting phosphorus deficiency in the pasture.

Although long-continued phosphorus deficiency leads to the clinically recognisable disease “Styfsiekte,” especially in lactating animals, the less pronounced deficiency, manifested as malnutrition and stunting of growth, without direct mortality, is detected by blood analysis with equal certainty.
The determination of the volume and air space of soil clods
Authors: Russell E. W. , Balcerek W.
Published: March 2009

A method is described for determining the field volume and the air space of a clod of any shape by filling its pores with a hydrocarbon oil, such as paraffin or tetralin, and determining its weight in the oil and in air before and after impregnation. The method appears to work well for clods of any moisture content.

This method is shown to give values of these volumes entirely comparable with those given by the other accurate methods described in the literature. Its accuracy for clods of Rothamsted soil, weighing between 20 and 500 g., was probably at least 1 part per thousand, i.e. 0-1%.

The method has been applied to the determination of the available water held by a soil and has been used to illustrate the effect of long-continued applications of farmyard manure to a soil in increasing the amount of available water it can hold.
Infertility and neonatal mortality in the sow. IV. Further observations and conclusions
Authors: Pomeroy R. W.
Published: March 2009

During the course of the main investigation the following observations were made on some other aspects of reproduction in the sow.

An examination of the reproductive tract of sows killed at slaughterhouses in East Anglia showed a high percentage of cystic abnormalities in the ovaries (Perry & Pomeroy, 1956). However, the sample of sows necessarily excluded any gilts, so an examination has been made of the incidence of ovarian abnormalities in post-pubertal gilts at two bacon factories. The ovaries of 273 gilts were examined and divided into (a) ovaries containing corpora lutea, (b) ovaries not containing corpora lutea. These were then further classified as normal or abnormal. The chief criteria of abnormality were the presence of cystic follicles, i.e. of greater than ovulatory size (10 mm. in diameter) or cystic corpora lutea, i.e. large flabby corpora lutea with hollow centres. Gilts with numerous haemorrhagic follicles in the ovaries were also classified as abnormal, but it is quite possible that this condition is a common occurrence in gilts just before puberty. However, rather than underestimate the incidence of abnormalities these ovaries were classified as abnormal.
The transport of water through heavy clay soils. II
Authors: Nicholson H. H. , Childs E. C.
Published: March 2009

In a preceding paper(1) were deduced some of the consequences of assuming that water movement in a heavy clay soil is a process akin to diffusion. The only idealisation of the medium was the assumption that the ratio of k, the diffusion coefficient, to σ, the apparent specific gravity of the dry matter in the soil, is constant, independent of depth, and we shall see that this is justified by the experimental evidence. As long ago as 1907, Buckingham(2) showed that the quantity of moisture moving in a given time from a block of wet soil to a drier block in contact with it was dependent mainly on the difference between the respective water contents, and that there was no definite dependence on the actual water contents themselves. Veihmeyer(3), in 1927, placed blocks of wet soil between blocks of drier soil, arranged in a vertical column. Subsequent moisture profiles were typical of a redistribution obeying diffusion laws, and were nearly the same both for upward and downward movement. He demonstrated furthermore that the movement of the water in these conditions was extremely slow, and that the rate of movement was related to the difference in moisture content between the dry and wet soil. Unfortunately insufficient numerical data were given to apply diffusion theory to Veihmeyer's experimental results.
The growth of clover in the presence of ammonium sulphate
Authors: Caldwell J. , Richardson H. L.
Published: March 2009

It has long been held that the treatment of grassland with nitrogenous fertilizers, and especially with ammonium salts, reduces the clover content. This method has been applied also to the treatment of lawns and sports fields with a view to reducing the clover content of the turf. It has been suggested that the effect of the ammonium salts is to encourage the growth of the grass in competition with the clover, and also that the ammonium ions are specifically toxic to the clover plant. Since there is a growing volume of evidence that ammonium ions are, in fact, available to many plants and may be used by them directly, without nitrate-formation, it was thought desirable to examine the effect of the application of ammonium sulphate to clover plants grown in pots, where competition from grasses was not a factor in the consideration of the effect of manurial treatment.
Investigations on the root nodule bacteria of leguminous plants. XVII. Continued investigations on the effect of air content of the medium on the development and function of the nodule
Authors: Virtanen Artturi I. , Hausen Synnöve v.
Published: March 2009

The effect of the air content of the medium on the development and function of the nodule was studied with sterile cultures of peas inoculated with their appropriate strain of nodule bacteria.

In water cultures the plant grows well without added nitrogen, even though all nodules are submerged, if air is bubbled through the medium during the period of growth. Abundant nodulation occurs also in nonaerated liquid cultures; the nodules, however, are much smaller than in aerated cultures, and the plant grows poorly. Subsequent aeration of such cultures results in a distinct increase in the size of the nodules and improvement in the growth of the plant.

Nodulation is completely prevented by passing a stream of gaseous N through the medium. That oxygen is indispensable for the function of the nodules is shown also by the fact that the peas grow excellently on added nitrogen in non-aerated cultures.
Studies in the absorption and excretion of certain minerals by poultry. III. The influence of different levels of dietary calcium upon the retention of calcium, phosphorus, carbonate and chloride
Authors: Tyler Cyril
Published: March 2009

1. The daily retention of calcium, carbonate, phosphorus and chloride was studied using four birds and changing the calcium carbonate content of the ration every 5 days for 15 days.

2. It was shown that high calcium diets result in a much lower retention of calcium and thin-shelled eggs are produced.

3. Retention of calcium was higher in the laying than in the non-laying bird when calcium carbonate was fed.

4. High calcium diets depressed the retention of phosphorus, and in one case the retention was negative, even when no eggs were laid. Laying birds gave negative values for retention because of the heavy phosphorus excretion associated with egg laying.

5. High calcium diets also depressed the retention of chloride, and on occasion led to negative retention values.
Pollination studies with highly-inbred lines of winter beans (Vicia faba L.)
Authors: Toynbee-Clarke Gillian
Published: March 2009

Pollination treatments were carried out on highly inbred lines of winter beans over a period of four years.

Tripping produced an inferior seed-set compared with all treatments involving emasculation and hand pollination with either cross or self-pollen. It is suggested that with highly inbred lines the stigmatic surface requires some form of scarification to improve the seed-set. Most lines showed no preference for cross or self-pollen, and there was no evidence of self-incompatibility. Bud and mature flower pollination gave an improved seed-set over tripping in all lines.

One inbred line gave a high seed-set in all pollination treatments. Results from another line were consistent with a short period of ovule receptiveness.

Using data obtained from three experiments, two self-pollination treatments were used to screen breeding lines for their suitability as components of synthetic varieties. Significant differences in seed-set were found between the lines.
Complete diets given ad libitum to dairy cows—the effect of the level of inclusion of milled straw
Authors: Owen J. B. , Miller E. L. , Bridge P. S.
Published: March 2009

Complete diets were given ad libitum to dairy cows over a whole lactation in order to study the voluntary intake of food, lactation performance and efficiency of feed conversion. The effect of including four levels 16, 24, 32 and 40 % of coarsely milled barley straw in the loose mix was studied for diets based mainly on barley or on sugar beet pulp, using a double 4 × 4 Latin square design.

The results confirmed that cows can perform normally when given complete diets for extended periods. Dry matter and digestible energy intake was depressed at the higher levels of straw inclusion and milk butterfat content at the lowest level. The net efficiency of conversion of metabolizable energy (M.E.) into milk was higher at the higher levels of straw. It is concluded that complete diets for the self-feeding of dairy cows should contain a minimum of about 24 % of coarsely milled straw and that estimated metabolizable energy intake and production were depressed by including straw at higher levels.
The interaction between nitrogen and water in the growth of grass swards: II. Leaf area index and net assimilation rate
Authors: D'aoust M. J. , Tayler R. S.
Published: March 2009

The effect of nitrogen fertilizer and irrigation treatments on the leaf-area index (L) and net assimilation rate (E) of a monthly cut sward of Italian ryegrass (Lolium multifolium) is considered.

Response to nitrogen was due to increase in both L and E, whereas response to irrigation was largely due to increase in L.

The data show little evidence of a seasonal decline in E. This may have been due to the mid-season replacement of old tillers by new, and by the encouragement to new leaf production caused by periodic harvesting.
Statistical research on the digestibility in the cow: III. Carbohydrates
Authors: Paquay R. , Baere R. De , Lousse A.
Published: March 2009

The results obtained for the digestibility of the carbohydrates with 116 different rations fed to 242 non-pregnant dry cows and 96 lactating cows were studied.

Except for some roughages, reducing sugars, non-reducing sugars, and starch digestibility is always very high. Reducing-sugars digestibility is related to starch content and starch digestibility to crude-fibre content.

Pentosans and crude-fibre digestibility is related to dry-matter intake and to starch, pentosans and crude-fibre content. When the ration contains less than 12% protein, a significant correlation coefficient also exists between crude-fibre digestibility and protein content. But pentosans and crude-fibre digestibility depends above all on the nature of the feeds and on the stage of maturity of the forage.
Effect of straw bedding, crude protein content of cereals and of latitude in balancing daily rations of growing pigs
Authors: Braude R. , Lerman P. M.
Published: March 2009

Results of a co-ordinated trial carried out at twenty centres indicated that performance of growing pigs (20–90 kg) was not affected by straw bedding in pens, or by small differences in the protein content of barley meal which was used as the main cereal in the diet. Also, no adverse effects were observed when cereals only were fed in the morning and an appropriately balanced compound mixture was fed in the afternoon.
Milk-fed calves: 3. The milk intake, herbage intake and performance of suckled calves
Authors: Le Du Y. L. P. , Baker R. D. , Barker J. M.
Published: March 2009

Two trials were conducted to measure the herbage intake of South Devon cross calves suckling Hereford × Friesian cows and to test the validity of applying the relationships established between milk and herbage intake and milk intake and live-weight gain for artificially fed calves to suckled calves. In Expt 1 the milk and herbage intakes of eight calves were monitored. Their average milk consumption was 2250 kg and their growth rate was 1·14 kg/day. Both milk consumption and growth rate were higher than those recorded in other studies with artificially-reared calves. Nevertheless, it was possible to predict the herbage intake and growth rate of the calves from the relationship previously established for artificially reared calves. The nutrition of cows in Expt 2 was manipulated to induce changes in milk production and the consequent effect on the herbage intake of their calves assessed. Milk consumption was at a lower level and herbage intakes fell within the expected range. Herbage intake also responded to changes in the milk production of the cows. The observed herbage intakes and live-weight gains were similar to those predicted from previously established relationships with artificially fed calves.
Retardation of hypocotyl growth by prior heat stress in seedlings of cowpea, melon and tomato
Authors: Onwueme I. C.
Published: March 2009

Seeds of cowpea, melon, and tomato were planted in moist soil and subjected to a heat stress of 45 °C for 10 h on the day of sowing (day 0), 1 day after sowing or 2 days after sowing. The heat stress subsequently resulted in retarded hypocotyl elongation for all the crops, but the greatest retardation was due to heat stress applied on day 1 for cowpea, day 2 for melon, and day 0 for tomato. The growth-retarding effect of heat stress was associated with a delay, by 1 day, of the maximum rate of elongation of the seedlings.
Seasonal variation in oestrogenic activity, coumestrol and formononetin content of white clover
Authors: Saba N. , Drane Hilary M. , Hebert C. Nancy , Holdsworth R. J.
Published: March 2009

The oestrogenic activity, coumestrol and formononetin content of white clover collected during the months May to December 1970 and 1971 was assayed in mice. The results showed considerable variations in oestrogenic activity which did not seem to be associated with a specific time of year or quantitatively related to the coumestrol content of the pasture.
Rumen fermentation studies on two contrasting diets. 1. Some characteristics of the in vivo fermentation, with special reference to the composition of the gas phase, oxidation/reduction state and volatile fatty acid proportions
Authors: Barry T. N. , Thompson A. , Armstrong D. G.
Published: March 2009

Rumen fermentation characteristics were studied using sheep fitted with rumen cannulae. Diets of 100% hay and 20% hay:80% cooked flaked maize (concentrate diet) were fed at the maintenance level of energy intake as two equal portions per day. Both the gas and liquid phases of the rumen were continuously sampled over 33-h periods.

Concentrations of O2 and N2 in rumen gas inoreased during feeding, whilst concentrations of CO2 and CH4 decreased. Thereafter the concentrations of both CO2 and CH4 rapidly increased. The CO2: CH4 ratio increased rapidly following feeding; it declined to baseline levels 2–4 h after feeding the hay diet, but with the concentrate diet the decline took longer. O2 concentration declined rapidly following feeding and was stable within the range 1–3% for long periods. At no stage was O2 absent from the rumen gas phase. H2 comprised 100–1500 μ1/1 and 100–6000 μ1/1 of the gas phase in sheep fed the hay or concentrate diets respectively and its concentration increased very rapidly with the onset of eating. CO concentration varied between 2 and 16 μ1/1 in the rumen gas of hay-fed animals and was not related to time after feeding. In concentrate-fed animals CO comprised 0—130 μ1/1 of rumen gas and increased very slowly after feeding.

Eh and rH values ranged between —150 and —260 mV and 8·0 and 5·0 units respectively for rumen contents from animals fed the two diets. A diurnal cycle was evident, with the most oxidizing state being attained just before feeding, and the most reducing state just after feeding. The diurnal cycles were better denned by rH than by Eh. The magnitude of the decrease in rH (and pH) during feeding was greater for animals fed the concentrate than the hay diet. At no stage during feeding did Eh or rH change towards more oxidizing conditions. Changes in the concentration of H2 in rumen gas were related to changes in the rH of rumen contents.

VFA molar proportions showed no changes during the 24-h cycle with hay-fed animals but showed erratic variation with concentrate-fed animals. When two sheep fed the concentrate diet were sampled daily for 21 days, it was shown that VFA molar proportions were not constant.

It was concluded that the gas phase of the rumen was never completely O2-free, and that whilst a stable rumen fermentation existed in sheep fed the hay diet the fermentation appeared to be continuously changing in the concentrate-fed sheep, and on this last mentioned diet abnormal values for rumen gas composition and VFA proportions were produced from time to time.
Response of perennial and Italian ryegrass cultivars to temperature and soil water potential
Authors: Keatinge J. D. H. , Garrett M. K. , Stewart R. H.
Published: March 2009

The rate of leaf extension (LER) in swards of perennial and Italian ryegrass was examined in relation to daily mean air temperature. Cultivars studied were an Italian, an Italian-perennial hybrid, a tetraploid perennial and diploid perennial cultivars in three maturity groups. A range of response to temperature was apparent. The Italian, the hybrid and the tetraploid perennial cultivar showed higher LER values than those of the diploid perennials. Amongst perennial cultivars the tetraploid cv. Reveille was shown to have a lower rate of photorespiration than the diploid cv. Gremie. These data are discussed in relation to the use of daily temperature observations in predicting leaf growth.
Development of Microplitis rufiventris Kok at different temperatures
Authors: Hegazi E. M. , Kolaib M. O. , Fattah M. I. Abd-El
Published: March 2009

The solitary larval parasite Microplitis rufiventris Kok was recorded for the first time in Egypt by El-Minshawy (1963), parasitizing the lesser cotton leafworm, Spodoptera exigua Hbn. Since it could be an effective summer parasite of the cotton leaf-worm, Spodoptera littoralis Boisd., studies on aspects of its biology by Hegazi (1976), and Hegazi, Hammad & El-Minshawy (1977) have been extended to include the effect of temperature on its development.
A note on the effect of different amounts of NaOH application on digestibility by cattle of barley, oats, wheat and maize
Authors: Ørskov E. R. , Barnes B. J. , Lukins B. A.
Published: March 2009

The effect of different amounts of NaOH sprayed on whole grain on their digestibility by cattle was examined for barley, oats, maize and wheat. For all cereals the digestibility of fibre, dry matter and organic matter (OM) increased with increasing application of NaOH solution but responses were small at the highest levels used. The digestibility of OM was increased from 61 to 83% for barley, from 61 to 76% for oats, from 83 to 89% for maize and from 79 to 92% for wheat. The optimum amount of NaOH required differed between cereals, being about 3·0–3·5% for barley, 4·5–5·0% for oats, and 2·5–3·0% for maize and wheats. With oats, wheat and maize the digestibility was apparently increased more with NaOH treatment than by physical processing.
The growth and yield of winter cereals after direct drilling, shallow cultivation and ploughing on non-calcareous clay soils, 1974–8
Authors: Cannell R. Q. , Ellis F. B. , Christian D. G. , Graham J. P. , Douglas J. T.
Published: March 2009

The effects of direct drilling, shallow cultivation and ploughing on the growth of winter cereals (wheat and oats) are reported for the first 4 years of long-term experiments on two non-calcareous clay soils (stagnogleys), representative of soils occupying a large proportion of the cereal growing area of the U.K. These 4 years have been characterized by extreme contrasts in rainfall and wetness of the soil.

On a Lawford series soil, with 35% clay, although the treatments affected average grain yields none of the differences was large. With additional nitrogen fertilizer, the yield after direct drilling was significantly heavier by 6% than after ploughing. On the Denchworth series, with 50% clay, 4 year average yields were also similar after direct drilling and ploughing, but in individual years the treatments had large effects. In two wet years grain yields after direct drilling were 89 and 82% of those after ploughing, but in another year they exceeded by 16% those after ploughing, where lodging had restricted grain filling. In the unusually dry season of 1975–6 yields of winter wheat after direct drilling exceeded those after ploughing (by 14 and 6% on the Lawford and Denchworth soils respectively) and this was attributed to greater availability of water and deeper rooting in the spring. In a year of heavy wheat yields (1977–8) about 10t/ha was achieved on both soils irrespective of the method of cultivation. In this year, after prolonged wet soil conditions in winter, the response to additional nitrogen fertilizer was greater after direct drilling and shallow cultivation than after ploughing.

The concentration of nitrogen in the crops tended to be smaller throughout the growing season after direct drilling than after ploughing, especially on the Denchworth soil in the wettest season. The method of cultivation had no effect on the uptake of either phosphorus or potassium except on the heavier soil in the wettest year, when potassium uptake was restricted after direct drilling.

The results are discussed in relation to information on soil conditions and root growth also being obtained in these experiments.
Some factors affecting voluntary food intake in buffaloes. 3. Effect of concentrate feeding on intake of roughages fed to lactating buffaloes
Authors: Taparia A. L. , Sharma V. V.
Published: March 2009

Three experiments, each with six lactating Mehsana-Surti buffaloes, were conducted to investigate the effect of supplementary feeding of concentrates on intake of basal rations of berseem hay, maize silage or wheat straw and on the total intake of feeds in 3 × 3 latin square designs.

In the berseem hay experiment, concentrate feeding at 16·8 or 26·1% of hay drymatter intake (DMI) resulted in a decrease of hay DMI by 0·77 and 0·65 kg/kg concentrate D.M., respectively. Intake of total digestible nutrients (TDN) and digestible crude protein (DCP) of buffaloes receiving concentrates in addition to hay were not different from those receiving hay alone. The possibility of some chemical factor limiting feed intake has been indicated for these rations in buffaloes. Supplementary feeding had a little effect on milk production.

In the maize silage experiment, concentrate feeding at 14·5 and 27·7% of the silage DMI resulted in a similar increase of total DMI, thereby increasing the TDN intake and DCP intake. Appreciable increases in milk yield and solids-not-fat (SNF) content due to supplementation were noted, although milk-fat content tended to be low.

Voluntary intake of rations comprising wheat straw fed free choice with three levels of concentrates at 28·7, 48·0 and 68·8 % of straw DMI was studied in the third experiment. Concentrate supplementation had little effect on straw DMI with the result that intakes of total D.M., TDN and DCP on the medium and high proportions of supplements were higher than those on the low proportion. The milk yield, of buffaloes receiving medium and high proportions of concentrates with wheat straw increased significantly over those receiving the low proportion of concentrates. The SNF and milk-fat contents were similar on all the three treatments. The implication of physical factors limiting intake is discussed in the case of maize silage and wheat straw diets.

The lactating buffaloes failed to maintain their weights on either sole berseem hay or sole maize silage rations. Supplementary feeding helped buffaloes to register small weight gains on hay rations and substantial gains on silage rations. The buffaloes on wheat straw fed with three proportions of concentrates tended to put on a little weight. Multiple regression using pooled data of Expts 1 and 3 showed that the partial regression coefficient of metabolic body weight (kgW0·76) on TDN intake was not significant but that of 6% fat-corrected milk on TDN intake was, suggesting a close relationship between milk yield and food intake.
The effect of some factors on growth, development and yield of winter wheat
Authors: Holmes J. C. , Tahir W. M.
Published: March 2009

1. The effect of three factors (nitrogen level, time of nitrogen application and weed control) and their interactions on three different plant densities of winter wheat have been measured. Data concerning the growth, development and yield have been examined.

2. Plant populations of 104,000, 155,000 and 281,000 per acre produced on the average of all treatments 21·3, 22·4 and 23·2 cwt. grain per acre, respectively.

3. An increase in nitrogen fertilizer to the 2 cwt. sulphate of ammonia per acre level increased the grain yield of all populations. This response followed an increase in the number of tillers and an increase in the percentage of tillers producing ears. There was no significant interaction between nitrogen level and plant density. The nitrogen content of the grain increased with nitrogen level.

4. Time of nitrogen application did not affect the grain yield, although it did cause considerable differences in the growth and development of the plants. There was no significant interaction betweentime of application and plant density. The late application of nitrogen produced a lower yield of straw and a higher nitrogen content in the grain.

5. Weed control increased the grain yield of all plant populations, this increase following an increase in the number of ears per plant. There was a significant interaction between weed control and plant density. Weed control raised the yield of the low plant population by 3·9 cwt. per acre compared with 0·9 and 2·0 cwt. for the medium and high populations. Weed control also increased the nitrogen content of the grain.

6. The only other interaction concerning grain yield which was significant was that of weed control with time of nitrogen application. Weed control increased the yield of the early and late applications but inexplicably reduced the yield of the intermediate date.

7. It is concluded (a) that the experiment provided no evidence that the yield of a thin stand of winter wheat can be increased further by altering normal nitrogen fertilizer application or by altering the time of application of the fertilizer; (b) that for good results weed control is essential where the plant population is low.
The nutritive ratio/crude-protein relationships in ruminant and non-ruminant digestion
Authors: Glover J. , Duthie D. W.
Published: March 2009

In both ruminant and non-ruminant digestion, the nutritive ratio of a feed is shown to be very significantly related to the crude-protein content of that feed.

This confirms that there is a relationship between the total crude protein and digestible protein in a ruminant feed, and strongly suggests that there should also be a relationship between these two components in non-ruminant feeds.
Barley production from seeds treated before sowing
Authors: Chatterjee B. N. , Singh A. I.
Published: March 2009

Barley (Hordeum vulgare L.), an important cereal crop in India, is grown mostly under rainfed conditions on about 3 million hectares. Vigorous and rapid development of roots of cereals contribute considerably to drought resistance (Genkel, 1961; May, Milthorpe & Milthorpe, 1962; Abdel Rahman, Batanouny & Ezzat, 1967; Bhan, Singh & Singh, 1973; Chang & De Datta, 1975). Many workers (e.g. Abdou & El-Kobbia, 1976; Basu & Gupta, 1974; May et al. 1962; Bozhenko, 1965; Woodruff, 1969; Salim & Todd, 1968; Hussain, May & Aspinall, 1968; Shkolnik & Bozhenko, 1974) have reported that pre-sowing seed treatments increase plant vigour and grain production. The production of barley under rainfed conditions in winter (November–February) depends greatly on the extent to which it can exploit the stored soil moisture after the harvest of the previous crop grown with monsoon rains in India during June–October. The main objective of the study was to dermine to what extent the increase in seedling vigour caused by pre-sowing treatments of seeds can be exploited for increasing the production of barley which has to depend mainly on the continuously depleting soil moisture, after the cessation of monsoon rains, and to investigate the possible reasons for such variations.
Diagnosis of multiple pregnancy in ewes on a field scale
Authors: Rizzoli D. J. , Winfield C. G. , Howard T. J. , Englund I. K. J. , Goding J. R.
Published: March 2009

A radiography unit was developed with which two technicians and two assistants were able to diagnose number of foetuses in 400–600 ewes per day on farms. Diagnoses made between 100 and 120 days of gestation in flocks where weekly mating records were made were 95–98% accurate as judged by lambing records. In most flocks more than 90% of twin pregnancies were correctly diagnosed. Agreement between diagnoses and lambing records was reduced when weekly mating records were not available. The radiographic examination had no detrimental effects on ewes or lambs.
Thermal adjustments of steers (Bos taurus) to abrupt changes in environmental temperature
Authors: McLean J. A. , Downie A. J. , Jones C. D. R. , Stombaugh D. P. , Glasbey C. A.
Published: March 2009

Body heat storage changes of cattle were measured by means of simultaneous direct and indirect calorimetry and by thermometry in an environment that alternated in temperature between 12 and 25 °C. When the calorimeter temperature was increased deep body temperature (Tc) increased by approximately 0–5 °C, mean surface temperature (Ts) by 3 °C and mean body temperature (determined from calorimetry, Tb) by 1 °C, but these increases were not fully sustained during the next 24 h. Changes in the three temperatures were related by the equation: δTb = αδTc+(1-α) δTs where a was found to be 0·89±0·027 (S.E.).
Free proline accumulation during development of two wheat cultivars with water stress
Authors: Karamanos A. J. , Drossopoulos J. B. , Niavis C. A.
Published: March 2009

The course of free proline accumulation in leaves, stems, roots and ears was examined during the development of the wheat cultivars Yecora and Generoso grown in the field with or without irrigation. More negative values of leaf water potential were associated with higher amounts of free proline in the various organs. In most cases, proline accumulated more readily with increasing water stress before heading than after ear emergence in the leaves, stems and roots of both varieties. Differences between the two cultivars concerning the sensitivity of the mechanisms inducing proline accumulation to water stress existed mainly in the reproductive phase: Generoso accumulated proline more readily than Yecora. There is evidence that the increased amounts of free proline in Generoso can be associated with more effective dehydration and drought avoidance mechanisms.
Magnesium phosphate as a dietary supplement for lactating cows at spring pasture
Authors: Ritchie N. S. , Fishwick G.
Published: March 2009

A total of 76 cows in seven, trials over a 3-year period were given a supplement of 53 g magnesiiun phosphate (supplying 11 g Mg and 10 g P/day) in 1 kg of concentrate for 21 days after starting to graze spring pasture. In contrast with 79 comparable cows given no supplement, there were significant improvements in the concentrations of magnesium and phosphorus in the blood of the cows, and significant reductions in the incidence of individual cows with low values.
Seedling vigour and grain yield of cereals grown from seeds of varying protein contents
Authors: Welch R. W.
Published: March 2009

The effect of seed protein content on grain yield has been studied in varieties of spring barley, oats and wheat grown under differing cultural conditions. Grain yield was affected by seed protein content in one experiment where very low yields were attained, but the effects were inconsistent. No effect was observed in two other experiments made in a glasshouse and the field. In a growth-room experiment, seed with high protein content produced more vigorous seedlings than low-protein seed; these differences were accentuated by increasing seedling age at very low nutrient levels, but decreased with seedling age at normal nutrient levels. It is concluded from the results that variations in seed protein content are unlikely to have a significant effect on yield under practical conditions.
The effect of sire breed on the partitioning of dissectible fat in steer carcasses
Authors: Thompson J. M. , Barlow R.
Published: March 2009

Differences in the partitioning of fat in the carcass may affect ‘carcass quality’ and depending upon the particular market requirements the optimum partitioning of fat may vary. Differences in fat partitioning may also affect the accuracy with which total carcass fat can be predicted from an assessment of subcutaneous fat (Pomeroy & Williams, 1974).
Increase of numbers of cereal aphids by insecticide application as an aid to plant breeding
Authors: Lowe H. J. B. , Benevicius Lydia A. D.
Published: March 2009

Increase of pest populations to abnormal levels following application of pesticides is a well-known phenomenon which has been turned to advantage in work on host-plant resistance to insect pests. For example, increases in numbers of aphids followed treatment of potato with carbaryl (Sevin), DDT and other chemicals which killed aphid predators (Peterson, 1963) and carbaryl has been used where enhancement of populations of Myzus persicae was achieved deliberately (Radcliffe & Lauer, 1971; Tingey & Van de Klashorst, 1976). Interest in the possibility of breeding for resistance to cereal aphids, especially Sitobion avenae (F), has increased as more examples of differences between varieties have been reported (e.g. Kolbe, 1969; Hinz & Daebeler, 1974; Lowe, 1978, 1980; Stokes, Lee & Wratten, 1980). This aphid occurs sporadically in the field and natural enemies, notably predaceous and parasitic insects, may contribute significantly to this variation (Vickerman & Wratten, 1979), so the use of insecticides to reduce the effects of the latter appears a promising technique in the development of reliable field screening methods for plant breeding.
Effects of manipulation of number of tillers and water supply on grain yield in barley
Authors: Jones H. G. , Kirby E. J. M.
Published: March 2009

Summaey

The effects of several detillering treatments on dry-matter production and grain yield in barley were investigated in a series of pot experiments using two water regimes. When ample water was provided, even quite severe reductions in the number of tillers only slightly reduced grain yield in spite of large effects on total shoot dry weight. When all the plants were grown with the same amount of water, however, the plants with few tillers tended to have greater grain yield, higher water use efficiency (in terms of grain yield) and higher harvest index than the plants permitted to tiller freely. This effect was probably related to the greater transpiration rates from the freely tillering plants which led to their suffering a greater degree of water stress than the plants with few tillers. This led to the freely tillering plants having a greater proportion of sterile ears and a lower harvest index. Water stress apparently had no effect on the grain yield of the main shoot or first tiller. It is concluded that genotypes which produce few large tillers having a high rate of survival should be able to achieve relatively high yields in drought conditions without sacrificing yield potential under optimal conditions.
A Comparison of Herbicide-Treated and Handweeded Sugar Beet
Authors: Wilcockson S. J. , Scott R. K.
Published: March 2009

Experiments at Sutton Bonington in 1973 and 1974 compared the growth and yield of sugar beet which was handweeded at different stages with that where weed control was entirely by pre- and post-emergence herbicides, used alone and in various combinations. Data from the series of handweeding treatments enabled the crop's minimum weed control requirements to be specified. They indicated that an ideal herbicide would kill all the weeds present when applied at the six-leaf stage, persist in the soil to prevent weed infestation for 4 weeks, but not check the crop to the extent that recovery was incomplete. That the crop was capable of recovering from a degree of early check was clearly evident from the handweeded treatments; it proved possible for crops whose weights had been depressed by 25–30 % when first weeded to recover completely by harvest.

The performance of all post-emergence treatments fell short of these requirements. When the crop was at the six-leaf stage, the earliest emerging weeds were too far advanced to be killed by the herbicide. By themselves, pre-emergence herbicides gave weed control equivalent to only 2 or 3 weeks of handweeding but they did pave the way for more effective use of post-emergence treatments by restricting the spectrum of weed sizes present and sensitizing those plants which did establish. The most effective herbicide regime used in the experiments was the sequence of chloridazon applied pre-emergence followed by two post-emergence applications of phenmedipham. However, phenmedipham clearly checked the crop. Two weeks after application crop dry weight was usually depressed by one-third. Provided weed control was adequate, recovery was usually complete by the end of the season.
Yield Potential of Heterozygous Seedling Lethal Mutants of Barley (Hordeum vulgare L.)
Authors: Rahman M. M.
Published: March 2009

The effects of homozygous and heterozygous loci of 20 seedling lethal mutants on yield and yield components of barley (Hordeum vulgare L.) were studied. Nine of the 20 populations studied exhibited one locus heterosis (positive or negative advantages of Aa genotype compared with AA genotype) for yield per plant or one or more components of yield. In five instances of significance all showed positive single locus (Aa) heterosis for number of seeds per spike. Seedling lethal mutants, Ac ac and Alb,, p alb,, p showed three yield-component-heterosis. These two mutants might be suitable for hybrid barley production.
Tillering of wheat as influenced by nitrogen and seed rate in the Sudan
Authors: Mahmoud Z. M. , Osman A. M.
Published: March 2009

SUMMAY

The pattern, production and survival of tillers was studied in two spring wheat varieties in field and pot experiments for two seasons.

The time-trend of tillering was such that tiller production reached a peak well before ear emergence, then death reduced the number of vegetative shoots to a level determined by seed rate (in the field) and nitrogen level (in field and pot experiments), and thereafter the number of live shoots remained more or less constant. In field experiments plants grown at high seed rates and low rates of N application attained their maximum numbers of shoots at an earlier date. Number of shoots perm2 increased with an increase in seed rate and N level. However, the number of fertile shoots per plant at harvest decreased with an increase in seed rate and were composed mostly of main shoots. The high mortality rate of shoots was attributed to the high temperatures prevailing in this country during the growth period. Mortality of shoots started earlier at high seed rates and low rates of N application.

In pot experiments, giving the N fertilizer in doses throughout the growth period reduced the rate of mortality of tillers rather than increasing their rate of initiation. A lower dose of N, given in portions over a long period, resulted in a higher number of live tillers than a dose double this amount given once at sowing. Numbers of spikelets and grains increased to a greater extent as a result of split application of N than did grain weight per ear of main shoots and of primary + secondary tillers. Mexipak had fewer spikelets per ear than Giza 155 and yet its number of grains was greater, particularly in ears of primary and secondary tillers.
The effect of soil physical conditions and nitrogen fertilizer on the yield of Italian ryegrass
Authors: El-Karouri M. O. H. , Gooderham P. T.
Published: March 2009

An experiment is described in which plots of a silt loam soil and a clay soil were compacted by ploughing when the soil was ‘wet’ or ‘dry’. Further plots were thoroughly loosened by hand digging. These treatments resulted in a wider range of soil physical conditions than had been obtained in a previous experiment.

A 2-year ley of Italian ryegrass was grown on the plots and was harvested twice in each year. Marked effects on crop yield were found at the first harvest but relative effects at subsequent harvests were much smaller. Yield responses to differences in soil physical conditions depended on stage of crop, levels of applied nitrogen fertilizer, inherent chemical fertility of the soil and distribution of rainfall during the growing season.
Effect of irrigation, pyrites and phosphobacteria on the efficiency of rock phosphate applied to lentils
Authors: Sharma S. N. , Ray S. B. , Pandey S. L. , Prasad R.
Published: March 2009

A field experiment was made at the Indian Agricultural Research Institute, New Delhi, during the autumn-spring season of crop years 1979–80 and 1980–1 to study the effects of irrigation, pyrites and phosphobacteria on the efficiency of Mussoorie rock phosphate(north-western Himalayan deposits) for lentils (Lens culinaris Medic), and residual effects were studied in maize (Zea mays L.). Response to phosphate was observed only when the crop received irrigation. Mussoorie rock phosphate was only 40·5% as effective as ordinary superphosphate; its efficiency was increased to 50·4% when it was mixed with 25% (by weight) pyrites. When the lentil seeds were treated with the culture of Pseudomonas striata (phosphate solubilizing bacteria) the efficiency of rock phosphate was increased to 79·7%. Rock phosphate together with seed treatment with phosphobacteria also showed residual effects on the succeeding maize crop which were equal to those obtained with ordinary superphosphate. Our results thus show that use of phosphobacteria can considerably increase the efficiency of rock phosphate on neutral soils.