Development of Yellow Rust-Resistant and High-Yielding Bread Wheat (Triticum aestivum L.) Lines Using Marker-Assisted...

Area of Science:

• Plant breeding and genetics
• Agricultural science
• Molecular biology

Background:

• Wheat yellow rust, caused by *Puccinia striiformis* f. sp. *tritici*, is a major threat to global wheat production and food security.
• Developing wheat varieties with durable resistance to yellow rust is essential for mitigating yield losses.
• Introgression of specific resistance genes is a key strategy in breeding for disease resistance.

Purpose of the Study:

• To develop yellow rust-resistant wheat lines by introgressing *Yr10* and *Yr15* genes into the high-yielding cultivar Grom.
• To utilize marker-assisted backcrossing (MABC) for efficient gene introgression and selection.
• To confirm the retention of desirable agronomic traits in the developed resistant lines.

Main Methods:

• Marker-assisted backcrossing (MABC) was employed to introgress *Yr10* and *Yr15* genes.
• Microsatellite markers (Xpsp3000 and Barc008) were used for foreground and background selection.
• Selected lines were advanced to BC2F2 and BC2F3 generations and evaluated for resistance and agronomic traits.

Main Results:

• Developed homozygous BC2F2 lines (Grom-Yr10 and Grom-Yr15) with introgressed *Yr10* and *Yr15* genes.
• The new lines retained key agronomic traits of the recurrent parent cv. Grom, including spike length and weight.
• Selected lines exhibited complete resistance (infection type 0) to yellow rust under artificial inoculation.

Conclusions:

• Marker-assisted selection integrated with conventional breeding is effective for developing disease-resistant wheat.
• The newly developed Grom-Yr10 and Grom-Yr15 lines provide valuable germplasm for future wheat improvement.
• These resistant lines contribute to sustainable agriculture and enhanced food security by reducing yield losses from yellow rust.