Biotech Updates

Seed Dormancy: Major Genetic Component of Pre-harvest Sprouting Resistance in White Wheat

May 28, 2010

Preharvest sprouting (PHS) is a major problem in the production of white wheat in rain-affected areas. PHS is characterized by the emergence of grains in a physiologically matured spike before harvest time. This is not favorable in production because the condition reduces the grain yield, nutritional value and processing quality of white wheat. According to previous studies, seed dormancy (SD) is the major factor that hinders PHS. Thus, Shubing Liu of Kansas State University, together with other researchers, identified the locations of genes controlling PHS in white wheat and the genetic relationship of PHS resistance and SD.

Based on a statistical method called quantitative trait loci analysis, resistance to PHS is a complex trait controlled by several stretches of DNA or quantitative trait loci (QTLs) and other nongenetic factors. Evaluation of the mapping population for both intact spike PHS and SD of threshed seeds harvested from field and greenhouse experiments showed that PHS resistance and long SD were both controlled by the same four QTLs.  Thus, SD is indeed the major component of PHS.

The abstract of this study is available at http://www.springerlink.com/content/m576431vw8564118/?p=63c68b96001f4daeb87cdd4ca15bc0e1&pi=4.