摘要:

AbstractBetween 1966 and 1969, 44 experiments on winter wheat tested 5 rates of N applied as spring top dressings of NH4NO3. At almost every site increasing the rate of N applied, decreased grain size and increased the N content of the grain. There was a marked effect of season: the sunniest season, 1969, produced the largest grain and the lowest mean N content; the season with the least soil moisture deficit, 1968, produced the highest mean N content. There was no relationship between N content and the variety of wheat or soil type. The N content of grain grown without N fertiliser was highly significantly related to reserves of available N in the soil. i.e. to the rate of fertilizer N required for maximum grain yield, determined by experiment. By using this relationship, the fertilizer N requirement at 20 sites with nil N plots was calculated and was found to compare favourably with the ADAS N Index prediction method based largely on previous cropping. Grain density was determined on three sites in 1967; with increasing rates of N, grain density increased slightly.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271102

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractThirty field experiments during 1969 to 1975 on Fenland farms in East Anglia tested response by sugar beet to manganese. The percentage of plants showing manganese‐deficiency symptoms or the concentration of manganese in the foliage during spring predicted response more reliably than soil analysis. The percentage of plants with symptoms was closely related to the concentration of manganese in sugar‐beet leaves and to the increased yield of roots from treatment, but correlations between plant and soil variables were poor. Analyses of exchangeable manganese extracted with normal ammonium acetate buffered to pH 7.0, the most reliable of several soil tests, predicted the occurrence of manganese deficiency. This test differentiated between fields of healthy and manganese‐deficient sugar beet but did not predict the magnitude of response to manganese treatment. A classification of fields where sugar beet are likely to respond to manganese is pres

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271103

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractNitrogen and potassium uptake and yields of perennial ryegrass, grown in controlled environments in three experiments, are examined in relation to the N and K status of the soil medium, defined by a (N/K)soilatom ratio. Maximum dry matter yields (DMY) were obtained at (N/K)svalues ranging from 4–40 for four “high K” soils and 10–90 for a “low K” soil. The N concentration in the crop increased approximately 50% with a ten‐fold increase in the (N/K)svalue although, in the “low K” soil, the relationship suggests that K deficiency may be limiting N uptake. No rational explanation can be given why the percentage N value in grass in one experiment is significantly less than in the other two. Exchangeable Na in “low K” soils is known to substitute for K during crop growth. Organic N in soils mineralises under favourable environmental conditions to provide N for crop growth. The possible contribution of these two factors to the observed relationships between N concentration and (N/K)s, and between (N/K)plantatom ratio and (N/K)svalues,

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271104

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractA method for the determination of volatile fatty acids, C1–C6, and lactic acid in silage juice is described. The procedure is simple and capable of application to large numbers of samples. It involves separation of the free acids by ion exchange, formation of their benzyl esters by the addition of benzyl bromide to a solution of the tetrabutylammonium salts in acetone and ultimate determination by gas liquid chromatograph

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271105

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractIn a field experiment comparing sulphur‐coated urea (SCU) and “Nitro‐Chalk” at rates up to 400 kg N ha−1, potato tuber yields were greater with “Nitro‐Chalk” at rates up to 200 kg N ha−1, but there was no consistent difference between forms of N at larger rates. The crop recovered more N from “Nitro‐Chalk” at all rates except 350 kg N ha−1. The largest measured yield was at 200 kg N ha−1with “Nitro‐Chalk” and 250 kg N ha−1with SCU, and the optimum N rate inferred from split‐line regressions of yield on N rate was also at a lower N rate with “Nitro‐Chalk”. Yields of winter wheat following the potatoes increased significantly with the N rates given to the potatoes and, at rates above 200 kg N ha−1, were larger where SCU had been used. SCU residues also lessened the response of the wheat to a spring top‐dressing of new N slightly more than those of “Nitro‐Chalk”. The sum of the apparent recoveries by the two crops of N given to the potatoes was greater from “Nitro‐Chalk” at rates up to 200 kg N ha−1. In the glasshouse, potato plants grown in 3 kg soil took 71 days to initiate tubers when given 2 g N as ammonium nitrate but this time was much decreased as increasing proportions of SCU were used. When 1 g N was given, the time was only 47 days with ammonium nitrate and the proportion of SCU had little effect. In the field, the number of tubers per plant by mid‐June decre

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271106

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractA field study of soils and pistachio nuts in three major pistachio‐growing areas of Turkey has been undertaken. The predominant soil fungus isolated from all three areas wasAspergillus niger; isolates ofFusarium, Trichoderma, MucorandRhizopusspecies were also common.A flavusandA. ochraceusand related organisms were isolated only from the plateau of Gaziantep. The dominant external mycoflora of the immature nuts from all sites consisted ofA. niger, A. flavusandPenicilliumspp. There was no evidence for fungal contamination of immature endosperms nor of freshly dehulled nuts, but stored dehulled nuts and dust samples taken from ware‐houses were extensively contaminated withA. flavus, A. nigerandA. ochraceus.Of 43A. flavusisolates tested, 20 produced aflatoxins on laboratory media or on rice; all 11 isolates ofA. ochraceustested produced ochratoxin A on laboratory media. The results obtained are discussed in relation to agricultural and marketing practices for Turkish pistachio n

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271107

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractAdsorption and desorption isotherms have been determined both manometrically and by weight equilibration for Turkish pistachio nut kernel, shell and hull. Comparison of the calculated and experimentally determined adsorption isotherms for whole nuts showed good correlation. Nuts inoculated withAspergillus flavusconidia were equilibrated to various ERH levels and stored in controlled environment cabinets at 28°C. Competitive growth of xerophilic strains ofA. amstelodamiprevented growth and aflatoxin production by theA. flavusat ERHs of 86% and below. At 88% ERH marked aflatoxin production occurred but competition was observed between theA. flavusandA. niger. In sealed containers metabolic moisture from growth ofA. amstelodamiraised the ERH from the initial 85% and permitted toxin production byA. flavus. The results are discussed in relation to post‐harvest handling and storage of pistachio nu

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271108

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractGas chromatrography–mass spectrometry, using the special sampling technique described previously, revealed 39 components in the headspace of red wine. Nineteen of the components have not previously been detected by headspace techniques and two are reported for the first time in wine aroma: dehydroionene (1,1,6‐trimethyl‐1,2‐dihydronaphthalene) and 2‐(ehtoxymethyl)furan. The latter is one of the compounds formed

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271109

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractA method is described in which the major water‐soluble proteins of soya meal—the storage globulins, glycinin and γ‐conglycinin, and the anti‐nutritional factors, Kunitz trypsin inhibitor and soya bean haemagglutinin—are resolved from one another in a single‐step chromatographic procedure. The method can be used as a basis for the preparation of these components, and also as an analytical tool for examining soya protein‐contai

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271110

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY

摘要:

AbstractA multi‐parameter scoring system for the sensory characteristics of the texture and flavour of meat or meaty products was developed. A trained panel used the system to give sensory data on 13 products. Principal Components Analysis of this data showed that the parameters of the system could be reduced to three independent components toughness, succulence and flavour, with little loss of information. The acceptability of the products (as measured by an independent panel of consumers) was shown to be predictable from the three derived components. Optimal acceptability regions in the three‐dimensional sensory space were then identif

ISSN:0022-5142    

DOI:10.1002/jsfa.2740271111

出版商:John Wiley&Sons, Ltd    

年代:1976

数据来源: WILEY