bluuebunny/crossref_metadata_2025 huggingface dataset:
The Composition of Irrigated and Non-Irrigated Apples
Authors: Jones J. S. , Colver C. W.
Published: March 2009

Expression is frequently given to an apparently widespread belief that irrigated in comparison with non-irrigated fruits are flat in taste and less resistant to the various agencies which effect decay. In support of that belief this statement in substance is almost invariably advanced: “The irrigated fruits contain abnormally high percentages of water and consequently low percentages of solid or dry matter; they are, therefore, deficient in the particular compounds upon which taste and body or solidity of structure depend.” We do not presume to say that from analyses alone can the many questions relating to quality in fruits be definitely settled, but since those alleged characteristics of irrigated fruits are charged by this statement to radical deficiencies in certain compounds, it would seem that analytical data would be of material service in the settlement of questions relating to quality. This view of the matter and the fact that here in the north-west, in both the irrigated and the non-irrigated sections, the hardy fruits are grown extensively and shipped to distant markets induced us to undertake some two years ago extensive analyses of fruits grown with and without irrigation. We wish to report here in summarised form the results of that work on the apple; for it, in point of commercial importance, stands pre-eminent among all other fruits grown in the north-west.
The Humus of Acid and Alkaline Peats
Authors: Hanley J. A.
Published: March 2009

The necessity for a method of comparing and, if possible, distinguishing chemically between the different classes of peat, and especially between alkaline or normal peats and acid peats, was suggested by a collection of soils received at the Rothamsted Laboratory.
Note on the increased Nitrate Content of a Soil subjected to Temporary Drying in the Laboratory
Authors: Buddin Walter
Published: March 2009

An interesting factor governing the nitrate content of a soil has been brought out in the course of the preceding work on the treatment of soil with volatile compounds.
Some Observations on the Flora and Fauna of Flooded Fenland
Authors: Petherbridge F. R.
Published: March 2009

On January 3rd, 1915, the Little Ouse burst its right bank not far from the Feltwell 2nd District Pumping Station, and as a result thousands of acres of fenland became flooded. The portion of the flooded land on which the following observations were made is a part of Southery fen situated near Southery, Norfolk. It lies between Peckett's Farm and Turf Fen Farm, and belongs to the Norfolk County Council. This land is some distance from the place where the burst occurred, and as a consequence there was no deposit of silt. The height of the flood here was about nine feet. The water was gradually pumped off and the land cleared by September, 1915.
The Maintenance Ration of Oxen and the Starch Equivalent Theory
Authors: Halnan E. T.
Published: March 2009

Within recent years, Kellner's system of starch equivalents has received much criticism from various quarters, and its value as a practical feeding system has been called into question. That the system is far from perfect in its working is universally admitted, and the recent work of W. Bruce with oxen has done much to emphasise this fact. In a series of practical feeding trials with oxen, Bruce obtained results contrary to those expected from the theoretical consideration of the Kellner system of starch equivalents, and largely on account of this work, and partly on account of the demonstration of the importance of the part played by certain unknown chemical compounds in the normal metabolism of animals, many workers have been led to suggest a total abolition of the Kellner system. It is, however, inconceivable to the author that a system based on 30 years continuous research upon feeding problems, should be condemned without the fullest possible enquiry. Furthermore it is supported by many experimental results. In a critical comparison of the values of certain foods for milk production theoretically computed by the Kellner system, Crowther has shown that the results obtained with one exception agree very well with those obtained in actual feeding practice. Moreover, with regard to the food deficiency factors which play such an important role, in the normal metabolism of animals, Hopkins has shown that those factors are hardly likely to be missing in normal dietaries, and consequently the results obtained in ordinary feeding trials will rarely be affected by lack of these factors.
Soil Gases
Authors: Leather J. Walter
Published: March 2009

At page 5 of their recent communication on the composition of soil gases Messrs Russell and Appleyard give some data regarding gas which was extracted from portions of soil which had been placed in flasks, the air pumped out and the soil then allowed to stand for one or more days. The authors state that “the total amount of gas given up is not great.” As a matter of fact a little consideration shows that the volume of this gas was indeed comparatively very large.
The determination of the number of bacteria in soil. II. Methods for the disintegration of soil aggregates and the preparation of soil suspensions
Authors: Whittles C. L.
Published: March 2009

1. An apparatus is described which has been designed to impart a known number of vibrations per minute to a suspension of soil or other material.

2. The problem of the calibration of the apparatus is briefly discussed.

3. A new method for the comparison of the mechanical composition of suspensions is described.

4. Various preliminary treatments of samples of soil for mechanical analysis are compared, and it is shown that:

(a) The rate of wetting is an important factor.

(b) A combination of triturition and vibration gives a satisfactory degree of dispersion.

(c) The use of acids is not advisable.
A note on the colorimetric estimation of humic matter in mineral soils
Authors: Eden T.
Published: March 2009

Odén has shown that colour intensity comparisons between alkali extracts of peat soils of varying origin can be made since, despite the possible difference in the nature of their humic matter, the absorption spectra are almost identical within the visible range. These absorption spectra are also comparable with that of Merck's Acidum Huminicum, which is a standard preparation. Odén developed his colorimetric method as a means of measuring the degree of humification of the organic matter of peat soils, that is to say, the proportion of the total organic matter which could be classed as humic matter. In this way the disadvantages of Grandeau's method, in which there is no discrimination between the coloured and the colourless parts of the soil organic matter, are obviated.
A chemical study of the development of the wheat grain
Authors: Woodman Herbert Ernest , Engledow F. L.
Published: March 2009

The connection which has been shown to exist between the strength of wheat flour and the chemical individuality of the glutenine fraction of the wheat protein (Woodman, 1922) (1) led the writers to institute an enquiry into the manner in which the individual wheat proteins are developed and stored during the progress of the grain from the early stages after flowering to ripeness. The immediate object of the investigation was to secure information in regard to the stages at which the different proteins made their appearance in the grain and to determine at what point the character of the grain contents was such as to enable a tenacious gluten to be obtained by grinding up the kernels with successive quantities of dilute NaCl solution. It was also intended to follow the rate of alteration of the amounts of the several proteins during the growth of the grain and to attempt to elucidate as far as possible the relationships which exist between the simple and complex forms of nitrogen at the various stages.
The chemical composition of animal bodies
Authors: Mureay J. Alan
Published: March 2009

Animal bodies are composed of fat and non-fatty matter. The relative proportions of these two ingredients vary within wide limits but can be controlled by food. The non-fatty matter consists of water, protein and ash. The percentage of water varies with the age of the animal in a definite manner. This has been determined with tolerable certainty for cattle. The available evidence indicates that the same formula is applicable to pigs and, with slight modification, also to sheep, but these inferences require confirmation. The ratio of protein to ash is the same in sheep as in cattle but in pigs it is higher. In any case it does not alter with the age of the animal but it may be influenced to a certain extent by the food. Individual variation is wider in pigs than in ruminants. The average composition of the whole body at any stage can be calculated when the live weight and percentage of fat in it are known.
The citric solubility of mineral phosphates
Authors: Tocher J. F.
Published: March 2009

The Fertilisers and Feeding Stuffs Act 1906, Section 10, defines the expressions “soluble” and “insoluble” to mean that the fertilising constituent is soluble or insoluble in water, or, if specified in the invoice, to mean that the fertilising constituent is soluble to the extent guaranteed in a solution of citric acid, or other solvent, of the prescribed strength. In particular the section defines the percentage of soluble phosphate and the percentage of insoluble phosphate to mean respectively the percentage of tribasic phosphate of lime equivalent which, has been, or that which has not been, rendered soluble. “Citric solubility” under the Act is further and more definitely defined in the Fertilisers and Feeding Stuffs General Regulations 1906 as follows:

“When, in an invoice relating to basic slag or basic superphosphate, it is specified that a certain percentage of the phosphate contained in the basic slag or superphosphate is soluble in citric acid, this shall be taken to mean that it is capable of being dissolved to the extent of such percentage when 5 grams of the fertiliser and 500 cubic centimetres of water, containing 10 grams of citric acid, are continuously agitated in a flask or bottle of about 1 litre capacity for the period of half an hour at the ordinary temperature.”
An investigation of the chemical changes taking place in the mixed lime sulphur-lead arsenate spray
Authors: Goodwin WM. , Martin H.
Published: March 2009

1. The reaction between lime sulphur and acid lead arsenate is shown to be small and to have little effect on the chemical properties of either material as a spray.

2. It is shown that the oxidation of lime sulphur proceeds according to the empirical formula:

CaS.Sx + 30 = CaS2O3 + Sx-1

and that the calcium sulphides are hydrolysed in aqueous solution.

3. The addition of lead arsenate has no effect on the amount of sulphur precipitated from the lime sulphur by oxidation or by the action of carbondioxide.

4. Lead arsenate is only slightly decomposed by lime sulphur or by the oxidation products of lime sulphur, the main decomposition being due to the action of sulphuretted hydrogen formed by the hydrolysis of the calcium sulphides. This decomposition becomes marked in the presence of carbon dioxide which reacts on the calcium sulphide to form sulphuretted hydrogen.

5. The fungicidal value of the mixed spray—as judged by the mildew killing properties of the polysulphides—is not less than that of lime sulphur alone. Additional fungicidal properties may be expected from the presence in the spray of soluble arsenates and thioarsenates.

6. Judging by the chemical changes which take place in the mixed spray the insecticidal value of the lead arsenate would not appear to be greatly affected by the addition of lime sulphur.

7. There is an increased amount of soluble arsenic formed by the action of carbon dioxide on the mixed spray which may prove sufficient in amount to cause spray injury.

8. The A.O.A.C. method for the determination of sulphate sulphur in lime sulphur solutions is shown to be inaccurate. A method yielding more concordant results is proposed.
Note on the Occurrence of Elementary Carbon in Soils
Authors: Robinson G. W. , McLean W.
Published: March 2009

In the course of determinations of organic carbon in soils, some unexpectedly high figures suggested the possibility that free carbon in the form of fragments of coal or cinder might affect appreciably the results obtained. The soils in question were from the Coal Measure district of Flintshire, and the presence of notable amounts of coal was not surprising. Even in soils from other districts, however, it is not unusual to find small carbonaceous fragments, which are generally noticeable in the coarse sand separated in mechanical analysis. Their presence is not difficult to explain, for domestic ashes containing unburnt coal or cinders are often thrown on to the manure heap, and thus get carted on to the soil where they persist unaltered. The highest proportions of elementary carbon may be expected in heavily manured soils such as those of gardens.
Mineral composition of leaflets in relation to the chlorosis and bronzing of oil palms in West Africa
Authors: Hale J. B.
Published: March 2009

Some disorders causing chlorosis and necrosis of the foliage of oil palms from three West African estates have been investigated by spectrochemical analysis of the dry leaflets for potassium, calcium, magnesium and manganese.

Statistical examination of the chemical analyses of leaflets from fronds of different ages, and from different positions along the frond, shows that it is important to sample and analyse separately at least upper, middle and lower fronds from each tree. Little is gained by analysing separately samples from different positions along the length of the frond.

The ‘bronzing’ diseases are tentatively ascribed to deficiency of potassium. One palm is probably a case of combined magnesium and potassium deficiency. One disease, ‘lemon frond’, cannot be attributed to a deficiency of any of the elements determined.

The differences in mineral composition of the leaflets between palms from the three estates are greater than those due to the diseases and a further survey is proposed to determine the range of variation of composition of healthy trees and the levels below which deficiencies set in.
The effect of pregnancy on the live weight of dairy cows
Authors: Bartlett Stephen
Published: March 2009

The figures analysed in the subsequent pages were obtained (by the kind permission and help of Prof. S. Pennington) during the five years, May 1920 to May 1925, from the College Farm dairy cows at University College, Reading, and before proceeding, a few notes on the herd and its management are desirable.

The herd is small (14–18 animals), and was established in 1908 by purchasing non-pedigree Dairy Shorthorn heifers which have since been “graded up” by the use of Pedigree Dairy Shorthorn bulls. The cows are typical Dairy Shorthorns, of a fairly large size, and the degree of fatness normally maintained might be described as good thriving condition, and probably better condition than average dairy cows.
Observations on the survival time of the spermatozoa in the genital tract of the cow and its relation to fertility
Authors: Laing J. A.
Published: March 2009

1. Experiments were carried out to determine the period of survival of spermatozoa in the genital tract of the cow.

2. No reliable results were obtained by searching, post-mortem, the genital tracts of two cows and three heifers killed at various intervals after insemination.

3. An attempt to induce ovulation at a definite time to which insemination could be related, in order that the survival time of the spermatozoa might be determined by the recovery of the ova post-mortem, was not successful. Of four cows and one heifer given pregnant mare's serum followed by pregnancy urine, one ovulated. To one animal, where a large follicle was present in one ovary, pregnancy urine was given. Ovulation occurred but could not be definitely attributed to the pregnancy urine.
Early reproductive failure of ewes in a hot environment. II. The uterus
Authors: Ryle Margaret
Published: March 2009

1. A balanced factorial experiment was carried out with forty-eight Merino ewes. There were two levels each of the four factors: environmental temperature, thyroxine status, vitamin A intake and progesterone status. Each ewe was killed at 25 days' pregnancy; its uterus was weighed and portions were prepared for histological examination. A number of morphological indices were then measured.

2. With respect to uterus weight there were significant interactions between thyroxine level, environmental temperature and progesterone level, and between thyroxine level and vitamin A intake. In the absence of thyroxine injections, heat and supplementary vitamin A increased mean uterus weight; in the absence of either of these, thyroxine injections increased it. Heat or vitamin A with thyroxine injections maintained normal mean weight. Progesterone influenced the temperature effect only in the presence of thyroxine.

3. Where thyroxine injections were given at normal temperatures uterus weight was significantly correlated with plasma vitamin A concentration. There was a similar correlation where thyroxine injections were given in the absence of dietary vitamin A.

4. There were no significant treatment effects or interactions on any of the histological indices examined. The height of the glandular layer of the endometrium, however, increased with increasing uterus weight, while the density of transected glandular tubules declined. There was no correlation between height of the stratum compactum or of the glandular epithelium and uterus weight.

5. In ewes with dead embryos the means of the following indices were significantly greater than in ewes with live ones: height of the stratum compactum, height of the glandular layer, height of the gland epithelial nuclei; the density of glandular tubules was less.

6. In the hot-room, gland epithelium height was correlated with mean rectal temperature.

7. Expansion of the glandular layer is not associated in all subgroups with more embryonic deaths and cannot therefore be their main cause. The observations do not indicate that early embryonic deaths are due to insufficiency of ovarian hormones; nor do they account for the marked improvement in viability associated with thyroxine injections.
An investigation of the method of Page and Williams for the determination of the saturation capacity of soils
Authors: Turner P. E.
Published: March 2009

1. The value of the knowledge of the saturation capacity of a soil as an aid in its characterisation and classification is briefly stated.

2. A short account is given of the more important methods in use for determination of saturation capacity.

3. The theory underlying the method of Page and Williams, and the possible defects of the method are discussed.

4. The results of an investigation of this method lead to the following conclusions:

(a) Leaching the mixture of soil and calcium carbonate to 2 litres is in sufficient to displace from the soil all its exchangeable bases.

(b) In view of this, it is recommended that 3 litres or more of filtrate be obtained, or preferably, the amount of soil employed be reduced to 10 grm.

(c) The leaching solution remains in contact with the soil mixture for a period adequate for the normal sodium chloride solution to be saturated with calcium carbonate.

(d) The difference in the amount of calcium, derived by solution from the carbonate, in the first and second litres of filtrate, is sufficiently small to be neglected.

(e) The tardiness with which the reaction proceeds to completion is probably due to the difficulty experienced in displacing the final amounts of adsorbed ions, rather than to the presence of calcium ions in the leaching solution.

(f) The incompleteness of the reaction renders the method of Hissink inaccurate for the calculation of the saturation capacity.

(g) The variation in the character of the colloidal material of soils i s to some extent reflected in the value of the ratio of the calcium passing into solution through exchange reactions in the second litre, to that dissolved in this manner by the total volume of filtrate.
Soil studies in relation to geology in an area in north-east Scotland. Part II. The soils and their development
Authors: Hart R.
Published: March 2009

Discussion and Summary

There are many areas throughout Britain where soil parent materials cannot be differentiated on the basis of solid geology alone, and difficulties are frequently experienced in classifying and mapping the soils. The object of this investigation was to study the parent materials and soils in a complex area of this kind.

The area selected is in north-east Scotland, and about half of it is covered by acid igneous and metamorphic rocks and the rest by sedimentary rocks of Old Red Sandstone age. The geology is complicated by three glaciations giving rise to diverse soil parent materials.

Five main groups of parent materials have been recognized, based on origin, texture and mineralogical composition. The first group consists of drift derived from acid igneous rocks and schists; the second of boulder clay from similar material plus an admixture of sedimentary rocks; the third of fluvioglacial deposits of varied textures; the fourth of conglomerate or thin drift from Old Red Sandstone rocks; and the fifth of boulder clay derived from Old Red Sandstone rocks where the influence of marls and shales in the drift is strong. Groups 1 and 5 are of major importance in this region and also elsewhere because of their widespread distribution. The others are more local.
The carotene and protein in oats and barley at different stages of growth
Authors: Smith A. M. , Robb W.
Published: March 2009

The amounts of nitrogen and β-carotene have been determined in oat and barley plants at different stages of growth and with and without a late top dressing of nitrogenous fertilizer. The nitrogen decreases steadily until the kernels begin to fill; it is markedly increased throughout by the extra dressing. The β-carotene, which accounts for about 80% of the ‘crude’ carotene in the oven-dried material, continues to fall until it reaches very low values when the crop is ripe. There is a very close correlation between total nitrogen and carotene in the plant.
The nutrition of the carrot: III. Grown in a gravel soil
Authors: Woodman Rowland Marcus , Johnson Delphine Ainslie
Published: March 2009

The nutrition of the carrot in a light gravel soil of known analysis with high available phosphate has been studied by statistical pot-culture methods, and the responses, linear and curvature components, etc., due to nitrogen, phosphate, and potash, have been calculated.

No hard and fast rule can be made as to the adequacy or otherwise of any particular fertilizer in a soil, as the different parts of the plant (top and root) were shown to be capable of responding quite differently to that fertilizer.
Oestrogenic activity in legumes
Authors: Drane Hilary M. , Saba N.
Published: March 2009

The teat-length increases observed in wether lambs grazing pure legumes have been compared directly with the oestrogenic activity demonstrated in mice fed samples of these pastures.

In the case of red clover, the mouse assay gives a good indication of the oestrogenic effect to be expected in the wethers. There was no such correlation when samples of clover and lucerne were tested. These were much more active in the wethers than would have been anticipated from the mouse assay, where lucerne and white clover appeared almost entirely lacking in oestrogenic activity.
Variation in the duration of gestation in the goat
Authors: Asdell A.
Published: March 2009

(1) A large series of data on the duration of gestation in the goat has been analysed and the constants calculated.

(2) The frequency curve is unimodal and symmetrical, suggesting a single factor or a variety of factors acting simultaneously as the cause for birth.

(3) Slight breed differences exist in the duration of gestation in the goat as in other species examined.

(4) There is a continuous variation in the duration of gestation with the time of year at which conception occurs. Spring conceptions give shorter gestations than autumn conceptions.

(5) There is a distinct difference in the duration of gestation for young and older dams. This is related to the age of the dams and not to the order of the births. Gestation is shorter in the young animal than in the older.

(6) In the goat the size of litter has little or no effect on the duration of gestation.

(7) Constants for duration of gestation in other species have been obtained. Variability increases with the duration of oestrus and about half the variability in any species with a long oestrous period may be ascribed to this cause.

(8) The factors involved in fixing the duration of gestation in the species examined are evidently the same in all cases, and probably culminate in a single agency responsible for terminating gestation.
The duration of pedigree herds in three breeds of cattle in relation to selective breeding.
Authors: Donald H. P. , El Itkiby A. A.
Published: March 2009

In the breeding of animals like cattle which reproduce slowly relative to the working life of a breeder, time is a factor of major importance. A study has therefore been made of the duration of samples of pedigree herds in order to obtain some indication of the time actually spent by breeders in the selective breeding of dairy cattle.

The samples consisted of pedigree Ayrshire, Jersey and Shorthorn herds, (a) established at various fixed times in the past; and (b) existing in 1939. The former were traced forwards, and the latter backwards, by means of herdbook registrations. Each sample contained not less than 300 herds, and the distribution of durations in each was considered in relation to the movement of population numbers in the whole breeds from which they were drawn.
The fungicidal properties of certain spray-fluids, V
Authors: Goodwin W. , Martin H. , Salmon E. S.
Published: March 2009

(1) A solution of dicalcium hydrogen arsenate at a strength of 0·0125 per cent. As2O5 was fungicidal to the conidial stage of Sphaerotheca Humuli, while at 0·006 per cent. As2O5 it was not quite fungicidal.

(2) Lime casein containing calcium hydroxide when added as a spreader to calcium arsenate was shown to reduce the fungicidal properties of the calcium arsenate spray.

(3) A solution of calcium thioarsenate at a strength equivalent to 0·006 per cent. As2O5 was fungicidal to the above fungus, while at 0·003 per cent. As2O5 it was below fungicidal strength.

(4) It is suggested that the increased fungicidal properties of the mixed lime sulphur-lead arsenate spray are due to the presence of calcium thioarsenates.
The effect on lactation of the length of the preceding calving interval and its relation to milking capacity, to age and to other factors of influence
Authors: Matson J.
Published: March 2009

Herd statistics of cattle in India suggest that for animals of about 3500 lb. yield capacity a calving interval of rather less than a year will give the best results in the following lactation. For cattle whose yield capacity is 6000 lb. an interval of 420 days is desirable while one of less than 335 days is seriously injurious.

Study of individual cows and their recorded histories reinforces the above conclusions and also suggests that the interval should be longer in early lactations than in late and progressively longer as the milking capacity increases.

It also indicates that unrestricted access to the bull may prevent the real yield capacity of a cow being discovered.
Quality of potatoes in relation to soil and season II. The colour of the cooked potato
Authors: Wager H. G.
Published: March 2009

Samples of potatoes were collected in three successive seasons from a wide range of soil types and their liability to stem-end blackening determined.

Variety and season of growth affected the amount of stem-end blackening which developed.

All soil types gave samples with a wide range of stem-end blackening, but the average amounts of blackening in samples from different soil types were shown to differ significantly. Samples from fen, blackland, sand, gravel, limestone and chalk blackened more than those from skirt, silt, warp, clay and boulder clay.

The pH of the expressed sap of tubers was independent of the type of soil in which they were grown, but dependent on variety and locality of growth. No evidence that the pH of the tubers influenced the amount of stem-end blackening pigment was obtained.

The yellowness of the flesh of tubers showed an approximately normal distribution. Slight evidence for an effect of soil type on the amount of yellow pigment was obtained.

The work described above was carried out as part of the programme of the Food Investigation Board of the Department of Scientific and Industrial Research.
The value of urea as a substitute for protein in the rations of dairy cattle: I. Field trials with dairy cows
Authors: Bartlett S. , Blaxter K. L.
Published: March 2009

1. A large-scale experiment with 274 dairy cows has been carried out to determine whether urea can be a substitute for part of the protein requirement of the lactating. dairy cow.

2. It has been emphasized that any proteinsparing effect of urea or other sources of non-protein nitrogen can only be determined in the proteindeficient animal and one of the experimental treatments was therefore designed to supply well below that minimum requirement of protein compatible with milk production.

3. The addition of protein to such a ration increasing the percentage of crude protein in the production rations from 12·9 to 17·9 and the protein equivalent from 9·5 to 14·5 resulted in a significant increase in milk production. This gave ample confirmation of the protein deficiency of the low protein ration.
The effect of feeding iodinated casein to pigs
Authors: Braude R.
Published: March 2009

Seven experiments are reported in which iodinated casein was fed to pigs. The daily doses varied from 0·25 to 1·5 g. of iodinated casein per pig daily for periods of several weeks. While the higher doses adversely affected the rate of growth of the pigs, the smaller doses were not sufficiently effective to have any practical importance.

The thyroid glands of the pigs receiving the iodinated casein appeared to be slightly smaller in size, but their histological picture was not affected.
Seed disinfection: VII. Mechanical principles
Authors: Dillon Weston W. A. R. , Eric Taylor R.
Published: March 2009

1. Substantial control of covered smut of wheat, Tilletia caries, was obtained when seed was treated with an approved organo-mercury seed disinfectant using both rotational and gravitational machines for mixing.

2. Good control of leaf spot of oats, Helminthosporium Avenae, was also obtained, using an approved organo-mercury seed disinfectant and mixing grain and powder together in a model rotational-type machine.

3. The model rotational machine gave an even mixing of grain and seed disinfectant with as few as forty-eight turns. Twenty-four turns was almost as effective but the mixing was much less even.

4. The gravitational machine was not so efficient in producing an even mixing as the rotational machine as assessed by the control of covered smut of wheat.

5. There was an indication that the rotational machine gave a better disease control.

6. Improvement was effected in the efficiency of mixing with the gravitational machine by the addition of a felt lining to the feed hopper.
Magnesium deficiency in some crop plants in relation to the level of potassium nutrition
Authors: Walsh Thomas , O'Donohoe Thomas F.
Published: March 2009

While numerous studies have demonstrated the essential role of magnesium in the normal development of plants, the information as to the soil conditions governing the availability of this nutrient is relatively limited. In general it is considered that a true lack of magnesium in the soil, such as might result from leaching or overcropping, is the main cause of magnesium deficiency in plants. This aspect of the problem has received considerable attention (Imp. Bureau, 1940). It has become evident in recent years, however, that the absorption of magnesium by plants may be depressed under the influence of an excess of other nutrients, notably potassium and calcium, in the soil. In some instances this has been noted to result in the onset of magnesium deficiency in plants, despite an apparently adequate concentration of this element in an easily available form in the soil as shown by chemical methods.

The literature having a bearing on the inducement of magnesium deficiency in this manner has been reviewed by Walsh & Clarke (1944). These workers, from a study of magnesium deficiency chlorosis in tomatoes, showed that it was induced by heavy dressings of potassium causing a depression in magnesium uptake. While the effect of potassium alone in this respect was sufficient to induce the deficiency, it was also found that the sulphate radical played a prominent part. Where potassium was added other than in the form of the sulphate salt, the onset of the chlorosis was retarded and the symptoms were reduced in severity.
Inheritance of plant growth characters and their relation to yield in wheat substitution lines
Authors: Monyo J. H. , Whittington W. J.
Published: March 2009

Attempts were made to relate various parameters of growth in wheat substitution lines to final yield of grain and assess the extent to which such relationships could be useful as early predictors of yield. The associations were measured by calculating correlation coefficients, partial regression coefficients, standard partial regression coefficients and independent contribution to yield. Significant correlation coefficients were common but significant partial regression coefficients were rare. The remaining estimates provided a ranked order of characters associated with yield. Those parameters of vegetative growth showing most association with final yield were themselves related fairly directly to ear and grain size. It was concluded that direct estimates of yield must remain the most appropriate character on which to base selection in cereals.
The losses in the tower silo
Authors: Woodman Herbert Ernest , Amos Arthur
Published: March 2009

An investigation has been described in which an attempt has been made to measure the losses of dry matter in a number of regularly spaced layers of silage contained in a tower silo, the immediate object being to determine theaverageloss of nutrient matter in the entire mass of material. The work was continued over the period of two silage seasons. The more important findings are summarised below:

1. It is usually asserted by writers on ensilage that the attainment of such high temperatures as are necessary for the production of “sweet” silage necessarily involves an excessive loss of the dry matter of the crop as a consequence of the oxidation of carbohydrate. This statement has been shown to be erroneous both on theoretical grounds and on the grounds of actual measurements of the losses of dry matter entailed in the production of “sweet” silage. The amount of destruction of carbohydrate bears no significant relation to the temperature attained during preservation, and the factors of (a) juice drainage, (b) bacterial decomposition of carbohydrate, (c) partial spoiling by undesirable bacterial activity, as with “sour” silage, are of much greater significance in causing unduly large losses of carbohydrate.

2. The results obtained in this investigation with crops containing from 26·5 to 33·9 per cent. of dry matter show that “acid brown” silage can be made in the tower silo with anaverageloss of dry matter equal to 5–6 per cent. of that contained in the green crop. It is further concluded that “sweet” silage, if made under good conditions, can also be produced in the tower silo with anaveragedry matter loss of the same order. With “green fruity” silage, theaverageloss under proper conditions of ensilage in tower silos is of the order of 8–9 per cent. The evidence affords strong disproof of the statement that the ensilage of green crops cannot be accomplished without large losses of nutrient matter.
The relationship between the chemical constitution of organic compounds and their toxicity to insects.
Authors: Tattersfield F.
Published: March 2009

1. The various classes of insecticides are outlined, and the sense in which the term “contact insecticide” is used is denned as one which is brought into external contact with the insect, either as solid, liquid or vapour.

2. An analysis is made of the relationships between chemical constitution and insecticidal action in the vapour phase. There is rough correlation between both the molecular weights and volatilities of organic compounds and toxicity, but it is probable that these relationships are only indirectly involved and that they indicate a connection of a more direct kind with some other property such as adsorption.

3. An account is given of the toxicity to insects of certain plant products. The most potent of these are certain tropical leguminous plants used as fish-poisons. A brief account is given of the chemical derivatives found in these plants. One of them, “tubatoxin,” is one of the most potent contact insecticides known.

4. A list of the groups of organic chemicals tested for their toxic action onAphis rumicisand the eggs ofSelenia tetralunariais given. A more detailed account is given for each group of the relationships between chemical constitution and insecticidal action. It is shown that the substitution of certain radicals in the benzene ring profoundly affects toxicity, but that toxic action depends not only upon the radicals but the number substituted and in certain cases upon their relative position.

5. 3 : 5-Dinitro-o-cresol is shown to have a most powerful ovicidal effect.

6. An examination of the toxicity of the fatty acids is made. It is shown that as the series is ascended toxicity increases up to undecylic acid, after which it declines.
Laterite and lateritic soils in Sierra Leone
Authors: Martin F. J. , Doyne H. C.
Published: March 2009

(1) The formation of laterite and lateritic soils in Sierra Leone has been studied and the mode of formation and the composition of these soils is described.

(2) It is suggested that since the clay fraction is regarded as the most important fraction in determining the reactions of a soil the classification of laterite and lateritic soils should be based on an examination of the clay fraction. It is further suggested that where the silica/alumina ratio in the clay fraction falls below 2·0 the soil should be described as “lateritic,” and where this ratio falls below 1·33 the soil should be described as laterite.
Wart disease infection tests
Authors: Bryan H.
Published: March 2009

A practical adaptation of a method devised by Miss Glynne for testing indoors the immunity or susceptibility of potato varieties to wart disease is described. The method consists of infecting by summer sporangia the young sprouts of the tubers under test. Extensive test has given such satisfactory results that there is little doubt that the method is infallible.

The writer wishes to render his grateful thanks to Mrs N. McDermott, who has been actively associated with him throughout the work described and who is largely responsible for the technique employed; to Miss M. D. Glynne, of the Rothamsted Experimental Station, for her many helpful suggestions; to Mr W. H. Parker, Director of the National Institute of Agricultural Botany, Cambridge, for his assistance and advice; t o Dr R. N. Salaman for supplying material for test, and to Dr G. H. Pethybridge for his kindness in examining tubers sent to him.
An Examination of Methods for Determining Organic Carbon and Nitrogen in Soils. (With One Text-figure.)
Authors: Walkley Allan
Published: March 2009

1. The details of the Dennstedt dry-combustion method for determining carbon in soils were described, and some simplifications suggested.

2. The Bangor modified Kjeldahl method for carbon and nitrogen in soils requires carefully standardised heating. Errors may arise from contamination of sandy soils by material abraded during grinding in iron or porcelain mills.

3. For many heavy soils the addition of water before the Kjeldahl digestion is convenient but not essential. For heavy alkaline soils with little organic matter it is advisable to grind the soil very finely and to add water.
The Placement of fertilizers: II. Cereals
Authors: Lewis A. H. , Strickland A. G.
Published: March 2009

Results are reported of sixteen replicated experiments on spring-sown barley and oats in south-east England to compare fertilizer sown in the drills with fertilizer broadcast. In thirteen of the experiments, fertilizer in the drills gave significantly greater yields of grain and straw than fertilizer broadcast, in two of the experiments the differences between the two were not significant; in only one experiment was the grain yield significantly greater where the fertilizer was broadcast.

Fertilizers were twice as effective when sown in the drills as when broadcast. On an average, broadcast fertilizer increased the yields of grain and straw by 4·0 and 6·3 cwt. per acre respectively. Drilling the fertilizer with the seed gave over double these increases, viz. 8·0 cwt. grain and 14·6 cwt. straw per acre.

Drilling the fertilizer with the seed tended to delay brairding. The crop on the fertilizer-drilled plots soon caught up and overtook that on the fertilizer-broadcast plots. Drilling the fertilizer with the seed increased tillering and decreased weed-growth.

Not more than about 3 cwt. of a soluble fertilizer per acre should be sown in the drills or the stand of plant may be poor. For the same amounts of soluble plant food, the higher the analysis of the fertilizer the less is the delay in brairding.

The possibility of obviating the delay in brairding by sowing the fertilizer near, but not in contact with, the seed is briefly considered.
Further investigations of the nutritive value of swill: starch equivalent, and seasonal variation in the composition and feeding value of concentrated swill
Authors: Woodman H. E. , Evans R. E.
Published: March 2009

An attempt has been made in the present communication to assess the value for pigs of urban swill collected during the winter months, when the main ingredients are potato peelings, cabbage leaves and other vegetable residues, and also during the summer months, at which period of the year the quality of the swill is at its lowest level, the product containing substantial proportions of pea pods, cabbage leaves and cabbage stalks. The form known as concentrated swill was used in the digestion trials, since regular and adequate supplies of this could be guaranteed, and, being already cooked, it did not require any heat treatment before feeding.

Chemical analysis showed that the winter swill, on account of the presence of the potato peelings, was distinctly richer in N-free extractives than the summer product. The latter, however, was richer i n protein and lime, and, as a result of the replacement of potato peelings by pea pods as the main ingredient, displayed a much more fibrous character than the winter swill.
Infertility and neonatal mortality in the sow I. Lifetime performance and reasons for disposal of sows
Authors: Pomeroy R. W.
Published: March 2009

1. A survey of the reasons for disposal of 1000 sows from farms in a selected area of East Anglia showed that the most important causes of sow wastage were ‘failure to breed’, ‘piglet mortality’, ‘old age’ and ‘low fertility’ which together accounted for 64·3% of the sows.

2. The average length of breeding life was 3·75 litters per sow and the modal number of litters was only two. This expectation of life is very short but is in agreement with an earlier estimate based on Breed Society records.

3. Failure to breed was the most important cause of sow wastage and accounted for 21·4% of the sows. The incidence of reproductive failure was greatest in young sows and of all the sows discarded as sterile 30·3% were discarded after having had only one litter. Cases of failure to breed were divisible into two broad groups.
The nutritive value for ruminants of a complete processed diet based on barley straw
Authors: Wainman F. W. , Blaxter K. L. , Pullar J. D.
Published: March 2009

Calorimetric experiments were made with a complete extruded diet for ruminants, ‘Ruminant Diet A’ prepared by Messrs U.K. Compound Feeds Ltd. Twelve determinations of energy and nitrogen retention were made using sheep and it was found that the diet had a metabolizable energy value of 2–32 kcal/g organic matter, and the net availabilities of its metabolizable energy were 42–7 % for fattening and 68–0 % for maintenance. These values agreed well with those predicted from equations published by the Agricultural Research Council. On a dry basis the starch equivalent was 38–3 %.
Grazing management practices and their relationship to the behaviour and grazing habits of cattle
Authors: Johnstone-Wallace D. B. , Kennedy Keith
Published: March 2009

1. The grazing habits of Aberdeen-Angus and Hereford beef cows, on pasture without supplementary feed, were studied over continuous periods of 24 hr. during the months of July, August and September. The pastures were from 3 to 7 acres in extent and contained a good growth of Kentucky bluegrass and wild white clover, with an average moisture content of 72 %.

2. During each 24 hr. period the cows spent from 7 to 8 hr. only in grazing, whatever the length of the herbage. Of this time, only some 5 hr. could be counted as actually employed in gathering herbage, as the remainder was spent in walking short distances and in selecting the area to be grazed. On the average 60 % of the grazing was performed by day, when the average distance travelled was 2 miles, and 40 % by night, when the cows travelled only about half a mile. With a dense sward of from 4 to 5 in. in height, representing about 4500 lb. green herbage to the acre, each cow was able to consume about 150 lb. of green herbage, or 32 lb. of dry matter, daily. As the amount of green herbage decreased through grazing to 2200 and 1100 lb. respectively, the daily intake was correspondingly reduced to 90 lb. (20 lb. dry matter) and 45 lb. (10 lb. dry matter). On a pasture containing about 5000 lb. green herbage of about 10 in. in height, the average daily intake was only 70 lb. (20 lb. dry matter).

3. Records were made also (the average figure for the 24 hr. period being given in parentheses) of time spent in lying down (12 hr.); time spent in cudding (7 hr.); frequency of defaecation (12); amount of manure (46 lb., covering an area of 8 sq. ft.); frequency of urination (9); frequency of drinking (once only, usually in late afternoon); and frequency of suckling calf (3, each for about 15 min. at 8 hr. intervals).

4. The application of the results to pasture management is discussed.