Author
XIONG, Y - IOWA STATE UNIVERSITY | |
FEI, S - IOWA STATE UNIVERSITY | |
BRUMMER, E - IOWA STATE UNIVERSITY | |
KENNETH, M - IOWA STATE UNIVERSITY | |
Barker, Reed | |
JUNG, G - UNIVERSITY OF WISCONSIN | |
Warnke, Scott |
Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 9/30/2004 Publication Date: 10/31/2004 Citation: Xiong, Y., Fei, S., Brummer, E.C., Kenneth, M.J., Barker, R.E., Jung, G., Warnke, S.E. 2004. Mapping of quantitative trait loci (qtl) for forage quality in perennial ryegrass (lolium perenne l.). American Society of Agronomy Abstracts. Paper No. 4846. Interpretive Summary: Perennial ryegrass is widely used as a forage crop in temperate regions of the world. Improvement of forage quality has important effects on ruminant animal nutrition and is an important forage breeding objective. A segregating population of 170 progenies derived from a cross between “Manhattan” perennial ryegrass and “Floregon” annual ryegrass was grown in Gibert, IA and was analyzed for neutral detergent fiber (NDF), crude protein (CP), acid detergent fiber (ADF) and lignin (LIG). Near infrared reflectance spectrometry (NIRS) was used to determine NDF, CP, ADF and LIG. We found that a genetic region on linkage group 2 (LG2) was strongly associated with CP. A genetic region on LG1 was identified to be associated with NDF while another region on LG1 was associated with ADF. Another region associated with LIG was mapped on LG2. The correlation of these traits and the interaction between the genetic regions were determined. These genetic regions provide genetic locations where possible DNA differences in forage quality traits might be found, and these differential DNA sequences would help in ryegrass breeding programs. Technical Abstract: Perennial ryegrass (Lolium perenne L.) has been widely used as a forage crop in temperate regions. Improvement of forage quality has important effect on ruminant animal nutrition and is an important forage breeding objective. A segregating population of 170 progenies derived from a cross between “Manhattan” perennial ryegrass and “Floregon” annual ryegrass was grown in Gibert, IA and was analyzed for neutral detergent fiber (NDF), crude protein (CP), acid detergent fiber (ADF) and lignin (LIG). The genetic map with a total length of 607.9 cM was previously developed from 235 loci with an average density of one marker every 2.6 cM. We used this map to identify putative quantitative trait loci (QTL) associated with forage quality. Plants were harvested twice in August and September 2003, respectively. Near infrared reflectance spectrometry (NIRS) was employed to determine NDF, CP, ADF and LIG. The mapping results from two harvests found that a QTL region on linkage group 2 (LG2) was strongly associated with CP. A QTL on LG1 was identified to be associated with NDF while another QTL on LG1 was associated with ADF. Another QTL associated with LIG was mapped on LG2. The correlation of these traits and the interaction between the QTLs and the environment will be discussed. |