Utilizing Grain Yield Data from Wheat Demonstration Plots

Abstract

Wheat (Triticum aestivum L.) cultivar demonstration plots are used widely in Kansas to promote early adoption of high yielding cultivars. These single-replicate plots are often harvested, however, and yields are reported in local newspapers. The objectives of this study were to compare the relative yields of wheat cultivars in demonstration plots and in official winter wheat performance tests and determine the usefulness of demonstration plots as yield indicators. Using cultivar × environment mean square as an error term, significant cuitivar differences could be detected in five of 10 cropping districts, and correlations between demonstration plots and variety performance tests were significant in seven of 10 districts. The five districts with significant cultivar differences and correlations tended to be ones with relatively homogenous soil types. Hybrid wheat cuitivars dominated demonstration plots, but hybrids have not been widely accepted by farmers. Mean yields of demonstration plots over locations can be used as yield indicators, when they represent homogenous environments.

Genotype‐by‐Tillage Interactions in Hard Red Winter Wheat Quality Evaluation

“…Mam effects of cultivars and tillage systems were regarded ~s fixed effects and environments as a random effect. Gram samples of a cultivar were bulke~ across ~eplicates for ~ach environment• therefore the cultlvar-by-tlllage-by-envuonment mean ;quare was 'utilized for the error term (Ben-Hui et al, 1990).…”