Wang L.X. , Pang B.SH. , Liu L.H. , Li H.B. , Zhao C.P.

Beijing Engineering and Technique Research Center for Hybrid Wheat, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China
Rm 506, Bldg 1, #9 Shu Guang huayuan Zhong Lu, Haidian District, Beijing 100097, China
Author    Correspondence author
Molecular Plant Breeding, 2015, Vol. 6, No. 21   doi: 10.5376/mpb.2015.06.0021
Received: 20 Jul., 2015    Accepted: 22 Aug., 2015    Published: 10 Nov., 2015

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Wang L.X., Pang B.SH., Liu L.H., Li H.B. and Zhao C.P., 2015, Assessment of Wheat Variety Uniformity using SSR Markers, Molecular Plant Breeding, 6(15) 1-21 (doi: 10.5376/mpb.2015.06.0021)

Assessment of uniformity is important for wheat (Triticum aestivum L.) variety registration and protection. However, the current testing system, which assesses a range of morphological characters, is time consuming (8-9 months for winter wheat), often is altered by environmental factors, and is not suitable for the assessment of hundreds of samples. The objective of this study was to develop a procedure for the assessment of wheat variety uniformity using simple sequence repeat (SSR) markers. Based on the studies of the relationship between the homozygous loci ratio of SSR markers (SSR-HLR) and variety uniformity, and detection of seed purity using SSR markers, we here propose that wheat variety uniformity is assessed on the basis of estimation of seed purity and the SSR-HLR. A variety is uniform if its seed purity and SSR-HLR are both > 95%. A variety with an SSR-HLR < 91% and/or seed purity ≤ 95% is not uniform. The varieties with an SSR-HLR ranging from 91% to 95% require additional uniformity assessments in the field because not all of them are uniform or not uniform. Those varieties make up less than 10% of the varieties (300-400) assessed in wheat regional trials annually in our laboratory, thus SSR markers are suitable for uniformity assessment of ~90% of wheat varieties. The procedures for uniformity assessment based on seed purity and SSR-HLR are detailed here. On average, it takes only seven days to assess one variety following the proposed procedure and greatly shortens the assessment cycle. SSR markers are not altered by environmental factors. Therefore, rapid and accurate assessment of a large batch of varieties becomes possible.

Wheat variety; Uniformity; SSR markers; Homozygous loci ratio of SSR markers