Identification of quantitative trait loci for seed traits and floral morphology in a field-grown Lolium perenne x Lolium multiflorum mapping population

With 1 figure and 2 tables Lolium perenne L. (perennial ryegrass), and Lolium multiflorum Lam. (annual or Italian ryegrass), differ in several traits related to seed yield. Generally, L. multiflorum spikes are larger than L. perenne spikes, and have more spikelets, more florets per spikelet, larger seeds and awns. The greater number of spikelets and florets and larger seeds are associated with higher seed yield in L. multiflorum. Ryegrass (Lolium sp.) cultivars are produced by seed multiplication and understanding the genetics of seed production traits would aid in plant improvement. A total of 30 QTL for seed production related traits were identified in this study. The QTLs were primarily located on linkage groups 2 and 4 which appear to be the most important for distinguishing L. multiflorum and L. perenne. These QTL will be used to develop molecular markers for marker-assisted breeding and screening of L. perenne seed lots to detect seed contamination with L. multiflorum.