15. A choice of statistical evaluation criterion for data from an agricultural experiment with cv Enola wheat

Author: Krasimira Uzunova, Anyo Mitkov, Tonyo Tonev

DOI: n/a


In the experimental work with agricultural trials, the last but not insignificant steps are the evaluation of data and determination of the level of confidence compared with the control (untreated) variant. The cv Enola wheat was used in the study, treated with chlor cholin chloride (CCC) in different doses in two phenophases: BBCH 21-23 – beginning of tillering to noticeable three brothers and BBCH 29-31 – end of tillering, with a visible maximum number of brothers and the first node – at least 1 cm above the tillering node.

Seven variants were formed. The assay was performed in the Training and Experimental Base of the Department of Agriculture and Herbology, following a scheme of using a nonstandard design method with an orderly arrangement of the variants in four replications. The samples were taken from all variants by metrovka in the latter half of June in 2012 and 2013. Eleven quantitative traits were reported, associated with the growth and development of the plants. The obtained data were statistically analyzed by applying two parametric assessment criteria (Student and Fisher) t-test and F-test. Varying degrees of confidence were established in the compared variations after applying the above criteria in the assessment. When using the Student criterion, lack of evidence was established in 60.6% of all the comparisons, while the application of the Fisher criterion established only 46.9%. Therefore we can conclude that in agricultural experiments with a high degree of variability it is more suitable to use the Fisher criterion for data evaluation since the degree of variability has a direct impact on the accuracy of the study.