摘要:

AbstractEnzymes present inLeucaena leucocephalacan rapidly degrade mimosine to 3‐hydroxy‐4‐1(H)pyridone (DHP). At 45°C, half of the mimosine in macerated leaves is degraded in 4 min. This activity is confined to leaflets and lamina of the young pod, although mimosine also occurs in other tissues. Simple processing can give a leaf meal largely free from minosine, or can break down most of the mimosine in pods used as human food; the problem then becomes that of the toxicity of DHP. Leaf autolysis can be utilised to prepa

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340602

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractSpray treatment of cut lucerne (alfalfa) with 0.2m solutions containing carbonates of the alkali metal group increased mean dry matter content and drying rates above an untreated control. Dry matter content of lucerne sprayed with carbonates of caesium, rubidium or potassium was greater than that of lucerne treated with solutions containing sodium carbonate, lithium carbonate or left as untreated control, throughout the drying period. Drying rates at any given water content between 2.5 and 0.5 were also greatest for lucerne treated with solutions containing caesium, rubidium or potassium carbonate. Mean drying rate of lucerne sprayed with alkali metals was positively related to their ionic radius and increased from lithium to caesium.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340603

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThe effects of fertiliser N on the growth rate and nitrogen and pigment concentrations of spring barley throughout growth were measured at two locations in north‐east Scotland in consecutive years. Inorganic N in soil was also measured as were grain and straw yields at maturity. The results show that plant analysis, as early as 3 or 4 weeks after emergence of barley, was an effective assessment of soil N statu

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340604

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThe results of field experiments with spring barley at two locations in 1978 and 1979 were used to evaluate early season measurement of soil mineral N, plant N and chlorophyll, and nitrogen stress as indicators of straw and grain yields and N uptake at maturity. A new definition of N stress based upon rates of N uptake is proposed. Plant N and chlorophyll contents early in the season were positively related (P<0.001) to final N uptake. Early season N stress (based on growth rate) was negatively related (mainlyP<0.001) to grain yield and, less strongly, to N uptake. There appeared to be some advantage in using rate of N uptake rather than growth rate to define N stress for the purpose of predicting crop final N uptake.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340605

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractFish survival, growth and productivity are dependent on both biological and environmental factors. The latter can be distinguished as edaphic (which includes water quality) and morphometric (which includes lake and stream morphology). Climatic factors are relatively less significant in temperate waters, except over a long time scale, or over wide geographic areas. In the conditions characteristic of acid lakes— low pH, low calcium and high aluminium concentrations—survival may be reduced, growth may be affected and, consequently, productivity will be low. In spite of inconsistencies in the literature, it can be shown that at low pH (⋍ 4.5), a limiting concentration of calcium is about 1 mg litre−1and aluminium can have adverse effects at 250 μg litre−1within a limited range of pH. These three factors appear to interact. Taking age specific fecundity of adults and survival of eggs and fry, it is possible to predict the limiting conditions for maintenance, growth or decline of a fish population. At pH 4.5 and calcium<0.8 mg litre−1it may be expected that many lakes will

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340606

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThe glucosinolate content of three fodder kales, one fodder rape, one semi‐artificial rape and one radicole were determined. The major glucosinolates (mmol kg−1dry matter) were: in kale leaf, glucobrassicin (3.21) and sinigrin (3.12); in kale stem, sinigrin (5.82); in rape leaf, gluconapin (3.14) and progoitrin (13.99); in rape stem, gluconapin (3.29) and progoitrin (20.18); in semi‐artificial rape leaf, gluconapin (25.64) and progoitrin (9.00); in semi‐artificial rape stem, gluconapin (35.33) and progoitrin (12.08); in radicole leaf, progoitrin (4.74) and glucobrassicin (3.28); and in radicole stem, gluconapin (3.26) and progoitrin (5.53). The implications for plant breeding are di

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340607

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThe ‘B’ polypeptides of the storage protein (hordein) of barley were studied in 84 varieties. On the basis of acid gel electrophoresis the varieties were classified into 13 distinct groups. Contrary to the suggestion that varieties preferred for malting tend to show less intensity of staining of the faster moving bands of the ‘B’ fraction of hordein, no consistent association was found in this study. Thus the malting potential of some varieties may be less affected by protein composition than by other factors. The genetic linkage between theHor‐2 locus, specifying the ‘B’ group of polypeptides, and theMlalocus, determining resistance to powdery mildew (Erysiphe graminis), was illustrated by the similar groupings of varieties carrying the same resistance alleles, but exceptions were observed. Examples of the inheritance of hordein patterns are illustrated

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340608

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractA complete lipid assay of the egg contents from the New Zealand kiwi(Apteryx australis mantelli)was carried out and compared with that of the domestic hen. The proportion of lipid to protein in the kiwi egg (1:0.5) is nearly twice as great as in the eggs of the domestic hen (1:0.9). Hen's egg lipids also have lower quantities of triacylglycerols (65 %) and higher phospholipids (29 %) as compared with those of kiwi egg lipids as 83 % and 8 % respectively. The overall fatty acid composition from the individual major lipid constituents and protein amino acid composition of the kiwi egg matched those of the domestic hen.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340609

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractAn antiserum raised against a solanine‐bovine serum albumin conjugate has been characterised and shown to be specific for the glycoalkaloids found in commercially available potatoes. The antiserum has been employed at high dilution in an enzyme‐linked immunosorbent assay (ELISA) for the glycoalkaloids. The assay is sensitive and precise and has many advantages over alternative procedures currently employed. Potato sample preparation is minimal and no recovery factors are requi

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340610

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractAttempts to use pectic enzymes to stabilise the cloud and reduce the limonin content simultaneously in citrus juices were unsuccessful but led to several significant findings. Acid‐catalysed reactions and residual effects of inactivated enzymes were shown to play a more important role in cloud stability than had been generally recognised. The maintenance of resuspended cloud, sometimes used as a measure of cloud stability during storage, was not always related to the actual retention of cloud; and although it was directly related to water‐soluble pectin content, cloud retention was not. Factors controlling the solubility of limonin in orange juice appeared more complicated than previously thought and varied in their relative contribution from juice to juice. Other chemical reactions were involved besides the conversion of a non‐bitter precursor to limonin, and the changes induced by endogenous pectic enzymes in unpasteurized juice had a more important effect on limonin solubility than the changes following the addition of fungal pectic enzymes to pasteurised juice. Finally, the separation of micro‐crystalline limonin complicated limonin analysis of stored

ISSN:0022-5142    

DOI:10.1002/jsfa.2740340611

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY