Determinants of diet quality     

Thiele S  Mensink GB  Beitz R 《Public health nutrition》2004,7(1):29-37

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Analyses of Interactions of Wheat Cultivars in Tests for Resistance to Pseudocercosporella herpotrichoides     

V. Lind    S. Züchner    A. Spanakakis  A. Thiele 《Plant Breeding》1994,113(4):272-280

A total of 20 cultivars of winter wheat were tested by ELISA for resistance to Pseudocercosporella herpotrichoides in six environments and three growth stages. In a three-factor statistical analysis, the contribution of the different factors to their respective interactions was studied. The genotype × environment interactions exerted a considerable influence which could be reduced by increasing the number of test locations. Environments with a high disease level were less suited to measuring resistance than those environments with a medium level. Estimates of heritability from 0.54 to 0.78 show that successful selection may be possible using ELISA. Significant correlations of quantitative resistance at different environments were only obtained under similar environmental conditions (the same location, the same year) and with P. herpotrichoides populations of similar composition (the same inoculum). The contributions of the individual cultivars to the genotype/ environment interactions were not significantly different, except for ‘Roazon’ and ‘Rendezvous’. Due to high environmental effects in growth stage H5, the determination of quantitative resistance was more reliable in younger stages (65, 75). Nevertheless, the use of the values from that late stage did not reduce the genetic parameters (σ², h₂) if they were combined with the earlier measurements.  相似文献   

Chromosome locations of genes controlling ‘purple leaf base’ in rye and wheat     

Gilbert Melz  Volker Thiele 《Euphytica》1990,49(2):155-159

Summary Purple leaf base is expressed only if there is anthocyanin pigmentation in coleoptiles either in rye or in rye-wheat-additions. Genes controlling purple leaf base were found to be located on chromosomes 5R (An5), 4B (Ra2) and 6B (Ra3) using the trisomic set of rye cv. Esto and autoplasmic rye-wheat-additions, respectively.  相似文献   

Simulation modelling for orchard management     

J. Davis  G.F. Thiele 《Agricultural Systems》1981,7(1):21-36

A simulation model is presented for a typical Australian pome fruit orchard. The main routine calculates annual after-tax profit and sub routines generate optimum replacement age and stochastic variability due to hail and drought. The principal dependent variables such as prices, yields and costs can be changed as required to add flexibility for various practical circumtances. Two replacement policies are used, self replacement (270 trees/ha) and semi-intensive (715 trees/ha). Under mean price and yield conditions, converting the orchard to semi-intensive production gives an average annual improvement in profit of $13 000 over a 100 year simulation period. Results emphasised the need for earlier replacement of trees than is usual practice. Existing trees were replaced at 31 years of age and thereafter recycled at 46 year intervals. Application of regression analysis to produce iso-performance curves revealed important interactions between price, cost, yield and orchard profitability with price being the most sensitive parameter.  相似文献   

Effect of bran diet on organic acids in the gastrointestinal tract and apparent digestibility in weanling piglets     

E Schnabel  R Schneider  C Schubert  E Borchert  I Thiele 《Archives of Animal Nutrition》1984,34(10):689-697

Over a period of four weeks 88 piglets of an average weaning weight of 9.5 kg received rations with 2.1, 3.1 and 5.5% crude fibre in the original substance in the form of wheat bran. Between the 42nd and 49th day of life a digestibility investigation was carried out by means of Cr2O3, and on the 42nd and the 63rd day of life the organic acids in the complete gastro-intestinal tract could be ascertained, the causes of which are to be found in the lack of easily soluble carbohydrates (increased passage rate, bran quota). Due to crude fibre, the apparent digestibility of all nutrients decreased, which resulted in a lower live weight on the 63rd day of life. The effect of a bran diet in the alimentary prophylaxis of coli enterotoxaemia is thus furthermore substantiated.  相似文献   

Bibliography: Farmer knowledge and management of crop disease     

Jeffery W. Bentley  Graham Thiele 《Agriculture and Human Values》1999,16(1):75-81

Nearly all contemporary people subsist on cultivated plants, most of which are vulnerable to diseases. Yet, there have been few studies of what traditional people know – and do not know – about crop disease. Agricultural scientists in general are becoming aware of the potential contribution of social scientists and farmers in developing integrated management of crop diseases. The International Potato Center (CIP) has focused on stimulating farmer-scientist collaboration in developing management of late blight, a major fungal disease of potatoes and other plants. Understanding farmers' knowledge of this and other plant diseases is an important element in furthering such collaboration. Although not all agricultural scientists recognize the value of social science, this literature search shows that some agricultural scientists now actively collaborate with farmers, in ways that cross the boundary into social science research. During this search, much of the work we found was written by plant pathologists and entomologists. We found over fifty publications on farmer knowledge of crop disease, and we have annotated the material that we thought most relevant to farmer- scientist collaboration for research of crop diseases, especially late blight.  相似文献   

Parameterization of Freundlich adsorption isotherms for heavy metals in soils from an area with intensive livestock production     

Sren Thiele  Peter Leinweber 《植物养料与土壤学杂志》2001,164(6):623-629

Adsorption coefficients are valuable tools used to estimate the environmental relevance of heavy metal contamination. However, their determination with batch experiments is laborious. Thus, attempts have been made to deduce these coefficients from soil parameters. However, the application of the resulting parameterized equations to different sets of samples has often yielded poor results. Hence, the objectives of the present study were (1) to deduce basic soil properties governing the coefficients of Freundlich adsorption isotherms for Cd, Cu, Ni, Pb, and Zn, and (2) to derive parameterized isotherms and examine their accuracy. For this purpose, 30 topsoil and nine subsoil samples were investigated which represented one Podzol‐Cambisol‐Gleysol soilscape in an area with intensive livestock production in Lower Saxony, Germany. Total background concentrations (aqua regia digestion) of heavy metals in topsoils ranged from 0.290 (Cd) to 19.2 mg kg^—1 (Zn) and exhibited elevated mobilizable proportions (NH₄EDTA pH 4.6 extract) of 17 (Ni) — 66 % (Zn) from the total concentration. Background concentrations were higher in topsoils than in subsoils by factors of 1.7 (Ni) — 28 (Zn). These differences were assigned to the special situation of heavy metal input mostly originating from animal excrements. The isotherms obtained by batch experiments showed larger coefficients K_F for partition among soil solid phase and soil solution in topsoils than in subsoils by a factor of 3.5. The coefficients of the isotherms were significantly correlated with routinely determined soil properties such as cation exchange capacity and pH (R = 0.36—0.89). Parameterized isotherms were calculated for each metal by inserting the relevant parameters in multiple linear regression equations. Among these parameters were the soil pH, cation exchange capacity, total metal concentration, and the concentrations of organic carbon, clay, fine silt, and various pedogenic oxides. The K_F values, separately calculated for topsoils and subsoils, agreed well with those determined by batch experiments (R = 0.63—0.97). Therefore, parameterized isotherms are valuable tools for the prediction of heavy metal partition in soils from one soilscape and for a risk assessment in the investigated, densely stocked area and similar areas.  相似文献   

Buchbesprechung: Der oberflächennahe Untergrund in der Rhein‐Main‐Landschaft — Ein Exkursionsführer. Von A. Semmel     

Sren Thiele 《植物养料与土壤学杂志》2002,165(5):659-660

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Chromosomal Location of a Catalase Gene in Wheat Using Rye-Wheat-Additions     

V. Thiele  A. Seidel 《Plant Breeding》1990,105(1):78-79

Rey-cytoplasmic rye-wheat-additioons were analysed for catalase structural genes using polyacrylamide gel electrophoresis. A structural gene of wheat was found to be located on chromosome 4b and on telocentric 4bL, respectively.  相似文献   

Compound-specific δC and δH analyses of plant and soil organic matter: A preliminary assessment of the effects of vegetation change on ecosystem hydrology     

Evelyn Krull  Dirk Sachse  Andrej Thiele 《Soil biology & biochemistry》2006,38(11):3211-3221

Here we present δ¹³C and δ²H data of long-chained, even-numbered (C₂₇-C₃₁) n-alkanes from C3 (trees) and C4 (grasses) plants and from the corresponding soils from a grassland-woodland vegetation sequence in central Queensland, Australia. Our data show that δ¹³C values of the C4 grassland species were heavier relative to those of C3 tree species from the woodland (Acacia leaves) and woody grassland (Atalaya leaves). However, n-alkanes from the C4 grasses had lighter δ²H values relative to the Acacia leaves, but showed no significant difference in δ²H values when compared with C3 Atalaya leaves. These results differ from those of previous studies, showing that C4 grasses had heavier δ²H values relative to C3 grasses and trees. Those observations have been explained by C4 plants accessing the more evaporation-influenced and isotopically heavier surface water and tree roots sourcing deeper, isotopically lighter soil water (“Two-layered soil-water system”). By comparison, our data suggest that ecosystem changes (vegetation “thickening”) can significantly alter the soil hydrological characteristics. This is shown by the heavier δ²H values in the woodland soil compared with lighter δ²H values in the grassland soil, implying that the recent vegetation change (increased tree biomass) in the woodland had altered soil hydrological conditions. Estimated δ²H values of the source-water for vegetation in the grassland and woodland showed that both trees and grasses in open settings accessed water with lighter δ²H values (avg. −46‰) compared with water accessed by trees in the woodland vegetation (avg. −7‰). These data suggest that in semi-arid environments the “two-layer” soil water concept might not apply. Furthermore, our data indicate that compound-specific δ²H and δ¹³C analyses of n-alkanes from soil organic matter can be used to successfully differentiate between water sources of different vegetation types (grasses versus trees) in natural ecosystems.  相似文献