Identification of QTLs for nutrient contents of rice as forage.

A genetic linkage map of 85 SSR markers was constructed based on an F2 population derived from a cross between a cultivated rice "Taichung 65" (Oryza sativa) (♀) and a common wild rice (O.rufipogon) (♂).The markers in the linkage map were distributed on 12 rice chromosomes.The statistic software of Mapmaker/QTL 1.0 was used to detect QTLs for crude protein,crude fiber,ether extract,crude ash,silica,and water soluble carbohydrate contents.There were 3 QTLs for crude protein,1 QTL for ether extract,2 QTLs for silica,and 3 QTLs for water soluble carbohydrate.They were identified on chromosomes 1,2,4,7,8,9,10 and 11.Interval mapping identified 4 major QTLs and 5 minor QTLs.Major QTLs were qCEE-1 (explained 56.8% of variation) for the ether extract content,qCWSC-4 (explained 23.1% of variation) and qCWSC-7 (explained 25.0% of variation) for WSC content and qCS-9 (explained 15.9% of variation) for silica content.QTLs for crude fiber and crude ash contents were not detected.