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ARS Home » Research » Publications at this Location » Publication #234981
Title: Identification of wheat-Thinopyrum intermedium alien disomic addition lines conferring resistance to stripe rust

Author
item LIN, FENG - Agricultural University Of China
item SUN, QUAN - Agricultural University Of China
item XU, SHICHANG - Agricultural University Of China
item Chen, Xianming
item ZHANG, LIJUN - Agricultural University Of China
item ZHANG, CHUNYU - Agricultural University Of China
item XU, YUFENG - Agricultural University Of China
item MIAO, QING - Agricultural University Of China
item QU, BO - Agricultural University Of China
item LI, NAN - Agricultural University Of China

Submitted to: Canadian Journal of Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/1/2009
Publication Date: 5/1/2009
Citation: Lin, F., Sun, Q., Xu, S., Chen, X., Zhang, L., Zhang, C., Xu, Y., Miao, Q., Qu, B., Li, N. 2009. Identification of wheat-Thinopyrum intermedium alien disomic addition lines conferring resistance to stripe rust. Canadian Journal of Plant Science 89:569-574.

Interpretive Summary: Grass species Thinopyrum intermedium carries many useful traits for wheat genetic improvement. To identify genes conferring resistance to stripe rust in wheat genotype Zhong 4 (Z4) derived from a cross between common wheat and Th. intermedium, a cross was made between Z4 and a ‘Chinese Spring’ ph1b mutant (CS-ph1b). F1 and F2 plants of the cross were used to determine the mode of inheritance of resistance in Z4. Genetic analysis with stripe rust race CY31 indicated a single dominant gene confering resistance. The chromosome number in the root-tip cells of 10 F5 resistant lines (total 42 plants) was determined. Three alien addition lines (4-1-2-5-1, 5-1-2-1-1-5, 5-1-2-1-1-6) with the smallest chromosome number (2n=44) were identified. Each of the alien addition line was genetically stable. The results of genomic in-situ hybridization indicated that lines 5-1-2-1-1-5 and 5-1-2-1-1-6 were wheat-Th. intermedium addition lines with 21 pairs of wheat chromosomes and 1 pair of Th. intermedium chromosomes, while line 4-1-2-5-1 was a wheat-A. intermedium translocated-addition line with one Th. intermedium chromosome, one wheat-Th. intermedium translocated chromosome and 21 pairs of wheat chromosomes. These lines were all resistant to stripe rust. The wheat- Th. intermedium translocated-addition line (4-1-2-5-1) should be useful for wheat breeding programs for stripe rust resistance.

Technical Abstract: Thinopyrum intermedium carries many useful traits for wheat genetic improvement. To identify genes conferring resistance to stripe rust caused by Puccinia striiformis f. sp. tritici in Zhong 4 (Z4) derived from a cross between common wheat and Th. intermedium, a cross was made between Z4 and a ‘Chinese Spring’ ph1b mutant (CS-ph1b). F1 and F2 plants of the cross were used to determine the mode of inheritance of resistance in Z4. The genetic constitution of 10 F5 lines derived from the cross CS-ph1b × Z4 was analyzed by cytological observations and genomic in-situ hybridization (GISH). Of 201 F2 seedlings tested with race CY31 of P. striiformis f. sp. tritici, 147 were resistant and 54 susceptible. The segregation fit a 3 resistant:1 susceptible ratio, indicating that a single dominant gene conferred resistance to the race. Using the Shiff dyeing method, the chromosome number in the root-tip cells of 10 resistant lines (total 42 plants) was determined. Three alien addition lines (4-1-2-5-1, 5-1-2-1-1-5, 5-1-2-1-1-6) with the smallest chromosome number (2n=44) were identified. A total of 51 pollen mother cells were examined at metaphase (PMCs M) for meiotic chromosome pairing. Most chromosomes in each of the three alien addition lines were paired as a rod bivalent (48 PMCs) and only few appeared as univalents (3 PMCs), indicating that each alien addition line was genetically stable. The GISH results indicated that lines 5-1-2-1-1-5 and 5-1-2-1-1-6 were wheat-Th. intermedium addition lines with 21 pairs of wheat chromosomes and 1 pair of Th. intermedium chromosomes, while line 4-1-2-5-1 was a wheat-A. intermedium translocated-addition line with one Th. intermedium chromosome, one wheat-Th. intermedium translocated chromosome and 21 pairs of wheat chromosomes. These lines were all resistant to stripe rust. The wheat- Th. intermedium translocated-addition line (4-1-2-5-1) should be useful for wheat breeding programs for stripe rust resistance.