A disease of swedes is described and attributed to the action of an organism, probably Bacillus oleraceae (Harrison), but closely allied to Pseudomonas destructans (Potter). It is suggested after consideration of its appearance on various culture media, that these two organisms may be different growth forms of the same parasitic species.

In Part III of this series of communications we recorded that no mammary pigment could be found in the old sows that were examined by us, and we suggested the possibility that such pigment had previously been present and had been destroyed or removed during the periods of glandular activity.

Much work has been done in the past on the chemical composition of South African soils. The study of the physical properties of soils has, however, been somewhat neglected.

Transvaal soils differ from those of European countries in several important respects. In the first place, a large proportion of the soil is derived in situ from igneous rocks, and secondly, the country has never been glaciated in recent geological times. These two factors bear directly on the physical properties of the soils. Soil formation takes place chiefly by the chemical decomposition of rocks and only to a limited extent by mechanical disintegration. As a consequence we find in our soils very fine material, resulting from the chemical decomposition of easily weathered minerals, and rather coarse material which represents those rock constituents which are only subject in a limited degree to decomposition. In comparison with European soils particles of intermediate size do not play any dominant part in the mechanical make-up of Transvaal soils. Soils of alluvial origin are, of course, excepted. These latter occupy only a small area, but they are of considerable importance in the present stage of development of the country. Another factor which differentiates Transvaal soils from European ones is the presence in many of the former of finely divided hydrated ferric oxide. This feature will be discussed later.

The production of green beans was studied in sowings made from December to February, September to February, and from October to February in three seasons, and over six oonsecutive seasons for a mid-season sowing.

With September-October sowing the rate of emergence was slow, and establishment sometimes poor. Possible virus disease, and the lack of continuity of setting pods resulting from cool weather, were problems. Good yields were obtained from midseason sowings (31 October-18 December), up to 19·6 t/ha, with good yields for late sowings up to 13·9 t/ha in ^he first three seasons. In another three seasons mid-season sowings (late November-early December) resulted in poor yield due to periods of hot weather (> 35 °C max.) prior to and during flowering.

There was a relationship between quality and yield. The greatest yield and best quality green pods were obtained when conditions favoured rapid growth and rapid setting of pods, and when there was a high rate of pod maturation.

For yield of dry seed the early sowings were best, 3·6 and 2·8 t/ha in two seasons. A total of 460 mm of water was required for the first six sowings, but fell to 360 mm for the mid-February sowing (rainfall plus irrigation).

Although it was possible to grow beans over a 9-month period the January and early February sowings appeared to be the least risk prone with the present cultivars.

In an experiment with twenty-four Large White pigs fattened from weaning to bacon weight on a diet containing either 5 or 9% of dried Clostridium residues the latter was found to be an efficient protein supplement.

The authors wish to express their thanks to Dr S. J. Rowland who made all the chemical analyses involved, to the Directors of Commercial Solvents G.B., Ltd., who kindly supplied the product, and to Mr E. Gill, Works Manager of the above Company, for helpful collaboration.

The cattle of the Sudan are broadly classified into two main types, i.e. North Sudan Zebu cattle and Nilotic cattle. Of the former typo Western Sudan Baggara cattle are numerically important amounting in number to about six million head (Food and Agriculture Organization, 1972). Western Sudan Baggara cattle provide the bulk of beef consumed in northern Sudan and contribute considerably to the country's export trade in live cattle. The study herein reported was undertaken as a continuing research project directed at ascertaining carcass composition of the indigenous cattle in support of improved feeding and marketing procedures necessary as a base for developing the meat animal industry.

For 8 weeks after farrowing, sows were fed their standard ration (depending on the number of piglets being suckled) in either thirteen or fourteen feeds per week. The omission of one feed per week did not affect the performance of the 3-week-old litters whether reared indoors or outdoors. The response of the 8-week-old litters to sow-feeding system, however, appeared, from the limited data available, to be inconsistent over rearing environments, those reared outdoors being more affected by feeding system than those reared indoors. The outdoor reared litters consumed significantly more creep feed and were significantly heavier at 8 weeks of age than litters reared indoors, confirming previous observations. During the suckling period the sows lost on average 74·4 lb. in weight; weight loss was not influenced by environment or feeding system.

The relative importance of variation in the components of wool production to variation in wool production itself was estimated by two methods of analysis. About 30% of the attributable variation in total fleece weight was found to be due to variation in surface area and 70% was due to wool production per unit skin area. Between 50 and 60% of the variation amongst sheep in the latter character was found to be due to variation in fibre weight, the rest being attributed to variation in number of fibres per unit area (fibre density). The variation in mean fibre weight was further partitioned into 50 to 70% due to variation in mean cross-sectional area and the remainder to variation in mean fibre length.

Variation in wool production per unit skin area was also analysed according to growth period and position on the body. The results are discussed in relation to the partition of variance in wool production of other breeds.

A digestibility and metabolism experiment was carried out to study the effect of two levels of feeding Rhodes grass-concentrate mixed diets when the grass had been preserved as hay or as frozen grass. Twenty Awassi lambs were used.

The method of preserving the Rhodes grass did not affect the digestibility of dry matter, crude protein or nitrogen-free extract. However, the digestibility of energy and crude fibre was lower with the hay treatments.

A consistent trend towards higher digestibility of the diets' constituents was observed with the high level of feeding.

Acetic acid concentration in the rumen was lower with the hay than with frozen grass. Feeding the high level resulted in higher concentrations of volatile fatty acids in the rumen.

A highly significant effect of the level of feeding on the C2/C3 ratio was observed; the high level of feeding resulted in a lower C2/C3 ratio

There exists a large body of soil-water theory for ‘modelling’ soil-water movement and distribution. Yet simpler and sometimes cruder methods are often preferred. In part this preference is due to the fact that theory is not yet able to solve completely the more complicated situations that occur naturally, such as the intermittent application or removal of water in the presence of very hysteric soil-water properties. But in many instances it is due to the apparent difficulty of the analysis for the non-mathematically minded. For example, descriptions have been given of soil-water models, based on direct physical arguments, that are in fact finite difference analyses of the governing partial differential equations, but which make no reference to such equations or their existence. Indeed, the impression is sometimes given that soil-water physicists produce unnecessary, irrelevant and complicated analyses for something that is really quite simple. Unfortunately, the simpler approaches bypass possible complications that are revealed by the mathematically based analyses. It is therefore the purpose of this paper to take advantage of the close relation between the two approaches, and to draw attention to the steps that may be taken to avoid or reduce possible difficulties when following the simpler methods. In particular, it is hoped that the paper will lead to a more efficient use of computing facilities.

Attention has been drawn to the remarkable growth rates obtained in certain litters of pigs under farm conditions.

It has been pointed out that no explanation has been put forward to account for their occurrence.

The literature relating to the new dietary factor, physin (Mapson), essential for optimum growth and reproduction in experimental rats, trout and dogs, has been reviewed.

Experiments are reported in which rations, adequate as far as our present knowledge of essential dietary constituents goes, were fed to young growing swine. In each of three experiments, animals which received in addition 4 oz. of raw minced liver per day showed a 40 per cent. increase in growth rate compared with the controls.

When food intake was controlled according to the new method of individual feeding, the liver animals showed the same gains in weight as the animals receiving the basal diet alone.

A study was carried out during three successive years from 1970 to 1972 on different wool types. Breed groups involved were Merino (M), coarse-wool Barki sheep and five of their crosses. Traits studied were greasy-fleece weight, clean-fleece weight, kemp score and means of staple length and fibre diameter in the whole fleece.

The heaviest greasy fleeces were produced by ¾ followed by ⅝ M. Total average greasy fleece weight of the crosses was 3·43 kg. There was a general trend of increase in greasy fleece weight with increasing Merino proportion.

The total average percentage clean yield of the crosses was 42·2, and ½ M and ¾ M produced the heaviest clean fleeces. The total average clean fleece weight of the crosses was 1·44 kg. Skirting the fleeces caused a reduction in the within-fleece variability of staple length and diameter. Percentages reduction for staple length were 10·3, 9·6 and 14·6 and those for fibre diameter were 2·4, 5·0 and 9·5 in Barki, crosses and Merino respectively.

Barki had the coarsest diameter and the whole fleece of ¾ M showed the finest mean diameter of the crosses. The within-staple variability in distribution of fibre diameter was high in Barki and throughout the crosses. The average percentage medullated fibres was highest in Barki and decreased throughout the series of crosses. The ¼ M had the highest frequency medullated fibres of the crosses.

The longest mean staple in the crosses was produced by ¼ M. The within-fleece variability in staple length was generally low. In the crosses, the variability assumed slightly higher values than those of the parental breeds.

Kemp production was mainly contributed from the dorsal line, particularly from the back and hip.

As regards some wool and mutton characteristics, ⅝ M might be considered the most suitable cross-bred type.

With increasing Merino contribution in the crosses, the mean fibre diameter showed a decreasing trend, but a high within-staple variability was maintained throughout the crosses. Inter se mating, in most of the crosses, produced animals that showed relatively more uniformity between fleeces than either both or one of the crosses. Inter se mating of the different cross-bred types with selection of the desired uniformity in length and diameter would be recommended.

Two experiments were carried out in Scotland 1984 to study the efficiency of energy utilization by Suffolk × Blackface lambs. In the first experiment, a digestibility trial, the lambs were fed three diets: roughage (R) consisting of chopped dried grass; concentrate (C) containing 700 g whole barley, 225 g ground barley and 75 g fishmeal/kg dry matter (DM); and a mixed diet (M) containing 500 g of roughage and 500 g of concentrate/kg DM. The DM and organic matter digestibility coefficients of diet M were lower than the ‘expected’ values calculated by summation of the separately determined digestibility coefficients of the component feeds. Similarly, the metabolizable energy (ME) value was 4·0% lower than expected.

In the second experiment, 40 lambs of c. 20 kg live weight (LW) were offered 50 kg roughage DM (ME 9·74 MJ/kg DM) and 50 kg concentrate DM (ME 12·21 MJ/kg DM) either as a mixture (treatment M) or sequentially (treatment S). Lambs on treatment S took 33 days longer to consume their allocation of food than those on treatment M, but achieved a similar final empty body weight and empty body composition. This contrasts with results predicted by a feeding standards model for lambs of a similar LW offered diets of the same ME content. The longer feeding period, and hence greater overall maintenance requirement, of lambs on treatment S was partly offset by associated effects causing a reduction in the total ME available to lambs on treatment M, and partly to improved efficiency of energy utilization for gain and/or a lower daily maintenance requirement of lambs on treatment S. Allowing for associated effects and the adoption of a variable maintenance requirement in current feeding standards would result in a more accurate prediction of animal performance.

Two experiments with growing pigs showed that the addition of L-lysine hydrochloride to diets limiting in lysine content raised not only N retention but also true N digestibility as a percentage of the diet. The change achieved in amino acid balance had no consistent effect upon ED (digestible energy, kJ/g diet) and therefore the experiment did not support the hypothesis that non-linear changes in dietary ED, resulting from ingredient substitutions, could be attributed to associated changes in amino acid balance.

Bracken-dominated hill pasture was treated with combinations of bracken and pasture herbicides and two reseeding techniques against a background of fertilization and liming. Picloram and dicamba gave high levels of bracken control and reduced carbohydrate levels in the rhizome. Both paraquat or reseeding with minimal cultivations increased yield of digestible organic matter by reducing competition from native weed grass species and promoting better establishment of ryegrass.

As a nitrogen fertilizer for vegetable production in Britain ammonia has been used mainly for bruasels sprouts (Page, Tatham & Wood, 1974; Page, 1975a; Page, Wood & Case, 1976), and leeks (Page & Williams, 1977). These crops with long growing seasons allow considerable latitude in time of application of the ammonia. Summer and autumn maturing cauliflowers have not only a short growing season, but also have a physiological control of curd formation which appears to be insensitive to nitrogen supply (Salter, 1969; Salter & Fradgley, 1969). They are also usually transplanted into the field, and the root system is therefore restricted for at least part of the growing season. It is therefore desirable to know if the roots would reach the injected nitrogen in time, as, until the ammonia becomes nitrified, nitrogen movement in the soil is small (Page, 19756). Thus, time of application of the ammonia was considered likely to be important.

On-farm yield experiments were carried out in the Tombouctou region of Mali in 2009/10 under heat- and drought-prone desert conditions with three local landraces of seed-type watermelons. The landraces, named Fombou, Kaneye and Musa Musa by the farmers, exhibited distinct characteristics for fruit morphology, but in particular for seed traits. On average, the three landraces produced a fruit yield of 11·6 t/ha and an estimated seed yield of 364 kg/ha, with no significant differences among landraces. Kaneye showed the highest stability of fruit number/ha in different field environments, suggesting this landrace is the best among the three for a poor growing environment, whereas Fombou and especially Musa Musa responded positively to more favourable environments. Seed weight revealed a different trend, with Fombou as the most responsive to favourable conditions, while Kaneye and Musa Musa were less responsive. The yields obtained suggest that these local landraces of watermelon are valuable plant genetic resources for securing food supply in arid, heat- and drought-prone areas.

Carrots of Chantenay type wefe grown in cultures of a black fen soil shown by analysis to be deficient in phosphate but normal as regards potash. When phosphate was absent, the cotyledons, and sometimes the whole of the foliage, were dark bronze in colour. There was a statistically significant increase in yield following applications of phosphate, but a tendency for applied nitrogen and potash to diminish yield.

We thank F. Shaw, Esq., N.D.H., of the Cambs. C.C. Staff for Agricultural Education, for his assistance in obtaining the fen soil used in this experiment.

The edge effect (calculated as the mean of the two outer rows as a percentage of the mean of the four central rows of 6-row plots) was measured in ten comparative trials conducted in Cyprus during 1987–90, with two cultivars each of rapeseed, safflower and sunflower, and one cultivar each of barley and durum wheat. Grain, straw and total biological yields obtained from the outer rows were usually higher than those obtained from the central rows by 1–384%. In one trial with sunflower, the grain yield of the outer rows was only 64% of that of the central rows, which could not be explained, considering all the other data. Differences in edge effects between species and trials were significant. Grain yield estimated from the central rows was on average 53% of that estimated from whole plots, and this varied with species and season. Therefore, in comparative trials, the outer rows should be removed before harvesting. There was no significant edge effect on the oil content of the oilseed crops. Edge effects on harvest index, volume weight, 1000-grain weight and nitrogen content were generally smaller than those on yield, and on average ranged from 100 to 113, thus the values computed from the outer rows were only 0–13% higher than from the central rows.