Study of the assessment of quantitative characteristics in DUS testing of new zoysiagrass varieties

DUS testing provides a technical and authoritative basis for the protection of new plant varieties. Ten zoysiagrass varieties, including two candidate varieties, two similar varieties, and standard varieties, were selectedin the present study for DUS testing over two consecutive growing seasons. The test was strictly guided by DUS testing guidelines, published by the Ministry of Agriculture of China. The distinctness of eight quantitative characteristics were assessed by two methods (note and statistical analysis) to provide practical evidence for the assessment of quantitative characteristics of zoysiagrass DUS testing. The assessment of results from the two methods showed that quantitative characteristics with distinctness that were assessed by the notemethod showed non-significant differences by the statistical analysis method, whereas characteristics without distinctness showed significant differences by the statistical analysis method.To avoid such misjudgment of distinctness, the quantitative characteristics with distinctness assessed by the notemethod were further analyzed with the statistical analysis method. The results showed that the candidate variety of zoysiagrass Guanglü had distinctness in quantitative characteristics of stolon length of internode, leaf length, and seed kilo grain weight, whereas the candidate variety of zoysiagrass Z0413-1 had distinctness in quantitative characteristics of stolon length of internode, leaf width, and inflorescence numbers of spikelet.