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121.
Background
Research in plant science laboratories often involves usage of many different species, cultivars, ecotypes, mutants, alleles or transgenic lines. This creates a great challenge to keep track of the identity of experimental plants and stored samples or seeds. 相似文献122.
Picco F Zini E Nett C Naegeli C Bigler B Rüfenacht S Roosje P Gutzwiller ME Wilhelm S Pfister J Meng E Favrot C 《Veterinary dermatology》2008,19(3):150-155
Canine atopic dermatitis sensu stricto and food-induced allergic dermatitis are common canine skin conditions, which are often considered clinically undistinguishable. Several attempts have been made to describe populations of atopic dogs and determine breed predisposition but the results were often biased by the use of hospital populations as control group. The present study aims to describe a population of Swiss atopic and food-allergic dogs and to compare it with a data set representing more than 85% of all Swiss dogs. The study, which was carried out during 1 year in several practices and teaching hospital in Switzerland, describes a group of 259 allergic dogs, determines breed predisposition for atopic dermatitis and food-induced allergic dermatitis, compares the clinical signs and features of both conditions, and outlines the clinical picture of five frequently affected breeds. 相似文献
123.
Heinrich Wilhelm Weber 《Forstwissenschaftliches Centralblatt》1924,46(1):13-25
Ohne Zusammenfassung 相似文献
124.
Wilhelm Neubauer 《Forstwissenschaftliches Centralblatt》1938,60(16):497-510
Ohne Zusammenfassung 相似文献
125.
Wilhelm Tischendorf 《Forstwissenschaftliches Centralblatt》1926,48(6):383-389
Ohne Zusammenfassung 相似文献
126.
127.
Vernalization requirement, photoperiod response and earliness per se (EPS) of bread wheat cultivars are often determined using controlled environments. However, use of non-field conditions may reduce the applicability of results for predicting field performance as well as increase the cost of evaluations. This research was undertaken, therefore, to determine whether field experiments could replace controlled environment studies and provide accurate characterization of these three traits among winter wheat cultivars. Twenty-six cultivars were evaluated under field conditions using two natural photoperiod regimes (from different transplanting dates) and vernalization pre-treatments. Relative responses to vernalization (RRVGDD) and photoperiod (RRPGDD) were quantified using the reciprocal of thermal time to end of ear emergence, whereas earliness per se was estimated by calculating thermal time from seedling emergence until end of ear emergence for fully vernalized and lately planted material. An additional index based on final leaf numbers was also calculated to characterize response to vernalization (RRVFLN). To test whether the obtained indices have predictive power, results were compared with cultivar parameters estimated for the CSM-Cropsim-CERES-Wheat model Version 4.0.2.0. For vernalization requirement, RRVGDD was compared with the vernalization parameter P1V, for photoperiod (RRPGDD), with P1D, and for earliness per se, EPS was compared with the sum of the component phase durations. Allowing for variation in EPS in the calibration improved the relation between observed versus simulated data substantially: correlations of RRPGDD with P1D increased from r2 = .34 (p < .01), to .82 (p < .001), and of RRVGDD with P1V, from r2 = .88 (p < .001), to .94 (p < .001). In comparisons of observed versus simulated anthesis dates for independent field experiments, the estimated model coefficients resulted in an r2 of .98 (p < .001) and root mean square error of 1d. Overall, the results indicated that combining planting dates with vernalization pre-treatments can permit reliable, quantitative characterization of vernalization requirement, photoperiod response and EPS of wheat cultivars. Furthermore, emphasize the need for further study to clarify aspects that determine EPS, including whether measured EPS varies with temperature or other factors. 相似文献
128.
Wilhelm Neubauer 《Forstwissenschaftliches Centralblatt》1938,60(17):544-555
Ohne Zusammenfassung 相似文献
129.
130.