Microsatellite Markers for Culm Wall Thickness and Anatomical Features of Solid Stem Wheat 86-741

Abstract

Lodging is a big problem in further increasing yield of wheat(Triticum aestivum L.) . Development of variety with thickwall of basal internodes is an effective way to improve lodging resistance in wheat. A solid stem line "86-741" has been developed from the cross between hexaploid Triticale and common wheat,and acted as parent in lodging resistance breeding. To detect the gene(s) of culm wall thickness in 86-741,we made a cross between 86-741 and a stem hollow wheat line "Xinjiang Daomai" [Triticum petropavlovskyi Udacz. et Migusch] in 2004–2005 growth season,and developed its F2 population in 2005–2006 growth season. The F2 population was used for bulked segregation analysis(BSA) of the gene related to culm wall thickness by SSR markers. Anatomical analysis revealed that 86-741 had very smaller stem pith cavity with pith,thicker mechanical tissue and more vascular bundles than Xinjiang Daomai. The F1 progeny of the cross showed some tendencies to its parent 86-741:culm with smaller diameters of pith cavity than the parent Xinjiang Daomai. The percentage of mechanical tissue in F1 was smaller than that in 86-741,and the number of vascular bundles in F1 was less than that in 86-741,but more than that in Xinjiang Daomai. Two recessive genes relating to pith and a single dominant gene on 3BL relating to culm wall thickness were detected in 86-741,respectively. The gene controlling culm wall thickness was temporarily designated as Cwt-1. We found 3 microsatellite(SSR) markers Xgwm-247,Xgwm-340,and Xgwm-547 linking to Cwt-1,in which Xgwm-247 was the closest to the gene with genetic distance of 5.3 cM. Our results indicated that Xgwm-247 can be used in marker-assisted selection(MAS) for lodging resistance breeding by selecting culm wall thickness trait in wheat.