Vol: 33 Page: 41

Authors:
Wiesław Pilarczyk

Title:
 Efficiency of incomplete block designs and spatial dependence in cereal variety trials.

Language: English

Keywords:
incomplete blocks
semivariogram
spatial dependence
spherical function

Summary:
In a paper the results of 174 trials on cereals conducted by The Research Centre of Cultivar Testing in the period 1998-1999 are reviewed. All these trials were conducted in resolvable incomplete block designs in four replicates. The data were analysed using randomised complete block approach (ignoring partition of complete superblocks into incomplete blocks) and using incomplete block approach. For each version of analysis the residuals in a field order were calculated and next used for calculating semivarigrams. These were next modelled using spherical function. It was shown that there existed spatial dependence in about 50% of all analysed trials and that it was efficiently removed by incomplete block analysis of variance.