| A normal isolate (E17, pink) of wheat powdery mildew (Blumeria graminis.f.sp.tritici) with a natural mutant (CPW-1,white) were crossed and ascospores released. A population with one hundred and seventy-five progeny individuals was obtained. The number of the progeny isolates for pink and white was 93 and 82, respectively. Genetic analysis for the segregation shows that the ratio of normal progeny to albino ones was approximately 1:1 (2=0.35<2 0.05, 1=3.84), indicating that a single locus confers the albino trait of powdery mildew. 82 selected progenies at random were tested on differential hosts with known resistance genes in greenhouse. The results show that avirulence matching Pm3b and Pm3f is controlled by one gene respectively. Each of avirulences matching Pml3, Pm4b, Pml3 and Pm22 is controlled by two dominant avirulence genes. Avirulence matching Pm (4a) is controlled by three dominant genes.A total of 200 random AFLP primer pairs were used to screen polymorphic DNA fragments and identify the AFLP markers linked to pigment gene between the parents and progenies Result shows that 25 primer pairs can amplify polymorphic DNA fragments. One polymorphic DNA fragment with the length of 700bp was amplified by primer pair E17M15 between offspring of normal and albino isolates. The genetic distance is 28.2cM. Furthermore, two pairs of primers (E16M19, E21M13) may link to genes that control the mating-type trait. The analysis is still on going.13 pairs of primers that selected from random primers were used to make AFLP analysis between parents and 74 progenies. Result shows that 22 markers linked in seven groups. The total distance is 173.4cM, with the average of 7.9cM. The remaining 17 markers were not linked to each other. The reason for this is probably due to the limited number of markers.
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