Identification and characterization of quantitative trait loci related to lodging resistance and associated traits in bread wheat

Lodging is a major constraint to increasing yield in many crops, but is of particular importance in the small-grained cereals. This study investigated the genetic control of lodging and component traits in wheat through the detection of underlying quantitative trait loci (QTL). The analysis was based on the identification of genomic regions which affect various traits related to lodging resistance in a population of 96 doubled haploid lines of the cross 'Milan' x 'Catbird', mapped using 126 microsatellite markers. Although major genes related to plant height (Rht genes) were responsible for increasing lodging resistance in this cross, several other traits independent of plant height were shown to be important such as root and shoot traits, and various components of plant yield. Yield components such as grain number and weight were shown to be an indicator of plant susceptibility to lodging. QTL for lodging and associated traits were found on chromosomes 1B, 1D, 2B, 2D, 4B, 4D, 6D and 7D. QTL for yield and associated traits were identified on chromosomes 1B, 1D, 2A, 2B, 2D, 4D and 6A.