Table 2.

Examples of gene or QTL pyramiding in cereals.

species	trait(s)	genes from parent 1	genes from parent 2	selection stage	DNA marker(s) used	reference
barley	barley yellow mosaic virus	rym1	rym5	F2	RFLP, CAPS	Okada et al. (2004)
barley	barley yellow mosaic virus	rym4, rym9, rym11	rym4, rym9, rym11	F1-derived doubled haploids	RAPD, SSR	Werner et al. (2005)
barley	stripe rust	RspxRspx	QTLs 4, 7 QTL 5	F1-derived doubled haploids	SSR	Castro et al. (2003)
rice	bacterial blight	xa5, xa13	Xa4, Xa21	F2	RFLP, STS	Huang et al. (1997)
rice	bacterial blight, yellow stem borer, sheath blight	Xa21, Bt	RC7 chitinase gene, Bt	F2	STS	Datta et al. (2002)
rice	blast disease	Pi1, Piz-5	Pi1, Pita	F2	RFLP, STS	Hittalmani et al. (2000)
rice	brown plant hopper	Bph1	Bph2	F4	STS	Sharma et al. (2004)
rice	insect resistance and bacterial blight	Xa21	Bt	F2	STS	Jiang et al. (2004)
wheat	powdery mildew	Pm2	Pm4a	F2	RFLP	Liu et al. (2000)