The COYU method and Bennett method. The empirical comparison of decisions concerning uniformity of crop plants cultivars
Bogna Zawieja
bogna.zawieja@up.poznan.plKatedra Metod Matematycznych i Statystycznych, Uniwersytet Przyrodniczy, Poznań (Poland)
Wiesław Pilarczyk
Katedra Metod Matematycznych i Statystycznych, Uniwersytet Przyrodniczy, Poznań (Poland)
Bogna Kowalczyk
Centralny Ośrodek Badania Odmian Roślin Uprawnych, Słupia Wielka (Poland)
Abstract
Before registration, each new variety of crop plants, has to be tested in terms of its uniformity. The decisions concerning uniformity of new varieties („candidates”) are taken for all tested characteristics, both quantitative and qualitative. In the case of qualitative characteristics, in the sample of fixed size, the number of non-typical plants is observed and if the fraction of such plants exceeds some threshold, this variety is considered as not fulfilling the condition of uniformity. In the case of quantitative characteristics the procedure is more complicated. The standard deviation of the candidate variety and average of standard deviations of registered varieties (sown in the same trial) is compared. The officially recommended method, in countries associated in UPOV organization, is so called the COYU procedure. This method is computationally complicated. Study of the homogeneity of variation coefficients is a much easier method, then the Bennett’s method can be used. A new method can be introduced to research methodology only when results obtained with new method are similar to the results of the previous one. Therefore, in this study, all the obtained results of comparison of both methods are summarized . These methods, in general, are consistent (in some of examples the COYU method was more restrictive, while in others it was the Bennett’s method, but these differences, usually, were not statistically significant).
Keywords:
Bennett’s method, COYU methods, OWT researches, simulation, uniformity of varieties, winter oil rapeReferences
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Authors
Bogna Zawiejabogna.zawieja@up.poznan.pl
Katedra Metod Matematycznych i Statystycznych, Uniwersytet Przyrodniczy, Poznań Poland
Authors
Wiesław PilarczykKatedra Metod Matematycznych i Statystycznych, Uniwersytet Przyrodniczy, Poznań Poland
Authors
Bogna KowalczykCentralny Ośrodek Badania Odmian Roślin Uprawnych, Słupia Wielka Poland
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Copyright (c) 2012 Bogna Zawieja, Wiesław Pilarczyk, Bogna Kowalczyk
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