摘要:

AbstractMagnesium is an essential plant nutrient but magnesium deficiency occurs fairly widely in Europe and North America, especially on light soils. In Great Britain this is known to be so for many horticultural crops, although information on deficiencies in agricultural crops is limited.Magnesium sulphate applied to the seedbed for potatoes increased yield in some but not all experiments on light soils, while in a few on both early and main crop potatoes it depressed yield.Deficiency symptoms often seen in cereals and sugar beet are usually transient, and in almost all experiments on these crops applying Mg has not increased yield.There is a well established interaction between Mg and K, and high rates of the latter can intensify deficiency symptoms and reduce the Mg content of the crop. Field experiments strongly suggest that the induced Mg‐deficiency from heavy rates of applied potash seldom reduces the yield of potatoes, cereals or sugar beet.Methods of controlling or averting Mg deficiency are discusse

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131101

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe acute effects of oral and parenteral sodium pyrophosphate on rats have been examined, with determination of the intraperitoneal LD50and the cause of death.Sodium pyrophosphate was included for 16 weeks at 1%, 2 1/2% and 5% levels and sodium orthophosphate at a 5% level in the diet of rats. The effects were assessed by examining gain in body weight, food intake, renal and hepatic function, blood cell counts, organ weights and gross pathology and micropathology. Calcium and phosphorus balance studies were carried out on some groups. Faeces and urine have been analysed for content of pyrophosphate.The intraperitoneal LD50of sodium pyrophosphate was 233 mg./kg., whereas the oral LD50was probably greater than 4 g./kg. The cause of death was not established.The low oral acute toxicity, the balance studies and the analyses of faeces and urine all suggest that pyrophosphate is converted to orthophosphate in the body. The site of such a reaction is being further studied.The longer term studies indicate that a 1% level of pyrophosphate in the diet of rats caused renal damage. The relevance of the finding to the ingestion of phosphate by man is discussed. Further studies are desirable on the metabolism of pyrophosphate and on the assessment of a safe phosphate intake for man.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131102

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractAmmonia volatilised from ammonium salts applied to calcareous soils was greatest from ammonium sulphate (AS), about half as much from mono‐ and di‐ammonium phosphates (MAP and DAP) and ammonium nitrate (AN), and negligible from magnesium ammonium phosphate.Losses of ammonia in 8 days from ammonium salts applied to an initially acid, sandy soil treated with calcium, barium or magnesium carbonates, were: soil treated with CaCO3, AS » DAP = AN; with BaCO3, AN » AS = DAP; with MgCO3, AS>AN » DAP.Reasons for these findings are discussed. It is evident that factors other than pH are ope

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131103

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractA new technique, based on an earlier calibration of the Brabender Extensograph, has been developed which allows the apparent coefficient of viscosity and the elastic modulus of dough to be obtained under a constant rate of strain. The results are discussed in relation to those given in the literature. The elastic modulus appears to be affected by test conditions to a far lesser extent than is the coefficient of viscosity. The new Extensograph method does not lend itself to the routine examination of flour properties because the evaluation of the results is laborious. Nevertheless it is of importance as a technique in studying, for example, the effect of oxidative flour treatment on the fundamental properties of dough behaviour and the biochemistry of the protein linkages involved.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131104

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractTwo experiments are described in which the fermentation changes in ensiled wet herbage were studied. In the first experimentLolium italicum, containing 19.6% of soluble carbohydrate, was used in four silos. Water was added in two silos during filling to reduce the dry matter content from 21.5%; to 17.0%. Although all four silages were well preserved the gaseous losses occurring in the ‚wet silages’︁ were almost three times those obtained from the drier materials. The addition in one treatment of a small amount of soil (0.1%) during filling did not affect adversely the fermentation changes.In the second experiment,Dactylis glomeratacontaining 6.2% of soluble carbohydrate was ensiled with and without the addition of water. In this experiment 2% molasses was added to two silos as an additional treatment. The resultant silages were not well preserved although the addition of molasses and water produced a silage of lower pH value than when water alone was

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131105

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe paralysis (knock‐down) and the subsequent recovery or death of female house flies treated by a measured drop method was studied with each of the four active constituents of pyrethrum extract alone and in the presence of piperonyl butoxide (1 part of pyrethroid + 10 parts of piperonyl butoxide) in n‐dodecane as solvent at 20°.Knock‐down was faster, lasted longer and the knock‐down end‐point was reached later when the flies were treated with the constituents in the presence of piperonyl butoxide. The synergist increased the overall efficiency of the constituents, probably because it inhibited the recovery mechanism of the flies. The effect of the synergist was least during the first few minutes after treatment; the synergistic factor increased most rapidly during the first 2 h, after treatment.Piperonyl butoxide changed the order and the magnitude of the relative toxicities from those obtained with the constituents alone. Four min. after treatment, when the effect of the synergist was very slight, the order of the relative toxicities of the mixtures, pyrethrin II, cinerin II, pyrethrin I, cinerin I, was the same as for the constituents alone. Three h. later it changed to (constituents alone in brackets) pyrethrin I (pyrethrin II), cinerin I (pyrethrin I), pyrethrin II (cinerin I), cinerin II (cinerin II) and it was the same at death (24 h. after treatment). Cinerin I and pyrethrin I were synergised most, cinerin II and pyrethrin II least, both during knock‐down

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131106

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe nodulation of S.100 Nomark white clover inoculated with an effective rhizobial strain was investigated. There was a wide range of variation in total numbers, size and weight of nodules and in the degree of symbiotic effectiveness, as indicated by the growth of the plants in a nitrogen‐free medium.The time taken to form the first nodule ranged from 4 to 16 days. Earliness of nodule formation and total nodule weight were significantly correlated with harvest dry weight, but there was no correlation between total nodule numbers per plant and harvest dry weigh

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131107

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractStarch‐gel electrophoresis has been used to study the compositions of several fractions obtained by extraction of hard wheat flour. The fractions soluble in water and in salt solution contained, respectively, 22 and 23 components. The extracts with 70% ethanol and dilute acetic acid each contained 10 major components and traces of others, while gluten contained 21 components. This number was reduced to 12 if the gluten was obtained from flour which had previously been extracted with water followed by salt solution. A total of 30 components appeared in a dispersion of the original flou

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131108

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractQuantitative aspects of the extraction from fresh and cold‐stored cod flesh of myosin as free as possible of actomyosin have been examined. A method for extraction of a large proportion of reasonably pure myosin has been standardised and used to study the changes in extractability of this protein during cold‐storage of cod flesh. It appears that 70‐80% of the myosin becomes non‐extractable at a rate similar to that at which the total myofibrillar protein of the flesh becomes non‐extractable. The remainder becomes non‐extractable at a very much slower rate. The implications of these findings in the mechanism of cold‐storage deterioration in texture

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131109

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe α‐ and γ‐tocopherol contents of eight different nuts have been determined spectrophotometrically on chromatographic fractions. Thin layer chromatography was applied to study the tocopherol pattern.The tocopherol contents were generally fairly high, but the values for α‐tocopherol varied greatly. Filberts and almonds were rich in α‐tocopherol, groundnuts and brazil nuts showed medium values, whereas walnuts, pecans and coconut were poor sources. Chestnuts had a very high γ‐tocopherol content as calculated

ISSN:0022-5142    

DOI:10.1002/jsfa.2740131110

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY