Evaluation on the Practicability of Molecular Markers of Powdery Mildew Resistance Genes in Wheat
|Tutor||DuJinYou; WangHaiBo; SunGuoZhong|
|School||Hebei Normal University of Science and Technology|
|Course||Crop Genetics and Breeding|
|Keywords||Wheat Powdery mildew resistance gene Molecular markers|
Wheat powdery mildew caused by the obligate parasitic fungi Blumeriagraminis f.sp.tritici is a serious disease in Chinese wheat production. Breeding newwheat varieties for resistance to disease is the most economic, safe and effectivemeasure to control wheat powdery mildew. The marker-assisted selection (MAS)makes powdery mildew resistance breeding more efficiency. At present, manymolecular markers for powdery mildew resistance genes have been reported, but mostof them lack breeding instances. Therefore, it is significant to evaluate the practicalityof known powdery mildew resistance genes using molecular markers. Aiming at thisproblem, this paper carried out the research from two aspects.Firstly, the powdery mildew resistance of145wheat cultivars (lines) and tenwheat lines carrying known as powdery mildew resistance gene was tested in seedlingstage. At the same time, these materials were identified using markers Xcfd81-5D(Pm2), Pm4a/b (Pm4), Xwg996(Pm6), LAG95(Pm8&Pm17), CAU196(Pm12),UTV14(Pm13), Xgwm159-5B (Pm16), Pm21D/E (Pm21) and Xgwm337(Pm24)above markers. The results indicated that the frequency of Pm8gene in145cultivars(lines) was52.4%, but the powdery mildew resistance conferred by Pm8has beenovercome. Pm2, Pm4, Pm6, Pm12, Pm13, Pm16, Pm17, Pm21and Pm24genes stillhad effective powdery mildew resistance，but the frequency of these genes in145cultivars (lines) was between0and9.7%. According to the conformity of phenotypicand molecular characterization, the wheat cultivars (lines) could be classified intofour types: Ⅰ.Phenotypic and molecular identification were consistent with thecontrol. II The phenotypic identification was consistent with the control, but themolecular detection was inconsistent with the control.III. The molecular detectionwas consistent with the control, but the phenotypic identification inconsistent with thecontrol. Ⅳ. Phenotypic and molecular identification were inconsistent with thecontrol. The molecular markers of above nine Pm genes could be used in molecularidentification of typeⅠ, typeII and type Ⅳcultivars (lines), but couldn’t be used intype III cultivars (lines). The Pm21D/E（Pm21）、UTV14（Pm13）could be used to detect all materials,and the other7makers couldn’t be used to detect some geneticbackground material.Secondly, used the contrast materials which contain powdery mildew resistancegenes, including Ulka/8cc (Pm2), Khapli/8cc (Pm4a+4b), Coker747(Pm6), CI14119(Pm12),96-282(Pm13),96-283(Pm16/Pm30), Amigo (Pm17),92R-137(Pm21) andChiyacao (Pm24) as the donor parent, and several execellent varities in Huang-Huaiwheat regions, such as Shi4185, Han6172, Jimai20and Jimai22as the recurrentparent to do rotary hybridization by “fast-breeding” technology in greenhouse.Thepracticability of molecular markers were evaluated by identifying the powderymildew resistance of hybrids in seeding stage and detecting the target genes bymolecular markers. The results indicated that Pm21D/Pm21E and UTV14markershad better conformity of phenotype characterization with the molecular detection intheir future generations, and the Xgwm337, Xwg996, Xcfd81-5D and LAG95hadlower conformity, but they still could be used in breeding progeny.