116
Chapter 6. Identification of Powdery Mildew Resistance in
Dasypyrum villosum Derived Wheat Lines**
ABSTRACT
Five amphiploids (2n=6x=42, AABBVV) derived from crosses between Triticum durum (2n=4x=28, AABB) and Dasypyrum villosum (syn. Haynaldia villosa , 2n=2x=14,
VV) and a series of 6D/6V disomic substitution wheat lines (2n=6x=42, AABBDD'-
6D/6V) were produced utilizing immature embryo and anther culture. The response patterns to 37 isolates of Blumeria graminis f. sp. tritici ( Bgt ) were tested in sixty-eight wheat lines. D. villosum and its derived wheat lines were immune or highly resistant to all tested isolates. The analysis of a series of populations, involving P
1
, P
2
, F
1
, F
2
, BC
1
F
1
, derived from crosses between susceptible lines and 6D/6V disomic substitution lines indicated that resistance was controlled by a dominant major gene, but it did not fit the expected 3R:1S ratio of resistance to susceptibility in most segregating populations when tested against different Bgt isolates in the laboratory and the greenhouse. The ratios changed in the various genetic backgrounds associated with different parents. An allelism test revealed that the resistance gene in 6D/6V substitution lines was Pm21 .
Fourteen RAPD markers were found to be associated with the resistance gene Pm21 . The markers, OPAI01
700
, OPAN03
1700
, and OPAL03
750
, were linked to Pm21 on chromosome 6V.
________________________________________________________________________
** Shi, A. N., Leath, S., Chen, X., and Murphy, P. J. 1997. Identification of powdery
mildew resistance in Dasypyrum villosum derived wheat lines (paper was prepared to
be submitted to Phytopathology).
D asypyrum villosum (2n=2x=14, VV) (Syn. Haynaldia villosa , Triticum

117 villosum ) is a potentially valuable source of resistance to fungal diseases (5,9,11). De pace et al. (1988) reported that an amphihexaploids (Mxv) (2n=6x=42, AABBVV) derived from Triticum turgidum var durum cv 'Modoc' x D. villosum and an amphioctoploid derived from T. aestivum x D. villosum were immune to both Blumeria graminis f. sp . tritici ( Bgt ) and Erysiphe graminis f. sp. haynaldiae (5). Chen et al.
(1997) reported D. villosum was resistant to more than 80 Bgt isolates collected from the
USA, UK, Germany, and China (4). The gene, Pm21 , was transferred from D. villosum into common wheat and a series of 6A/6V disomic substitution lines and 6AL-6VS translocation lines were developed (1,10,12,13,14). These wheat lines with Pm21 all have black awns, a trait closely linked to the Pm21 locus. Therefore, it is difficult to transfer Pm21 into cultivars without dragging the alleles for black awn.
Chen et al. (1996) made crosses between D. villosum and T. durum in 1983, and has successfully transferred powdery mildew resistance into T. aestivum utilizing immature embryo and anther culture (2,3). Five amphiploids (2n=6x=42, AABBVV) and a series of 6D/6V disomic substitution lines (2n=6x=42, AABBDD'-6D/6V) were produced (2,3, 15). Because all these 6D/6V wheat lines did not express the trait for black awn and are immune or highly resistant to wheat powdery mildew, the resistance is now likely to be utilized in the cultivar development. The objectives of this research are more fully to characterize the powdery mildew resistance in D. villosum derived wheat lines and to analyze its inheritance of resistance. While completing these objectives,
RAPD markers associated with the resistance in these derived wheat lines were identified. A preliminary report has been published (16).
MATERIALS AND METHODS
Development of 6D/6V disomic substitution wheat lines . Chen et al. (1996)

118 initiated crosses between D. villosum and T. durum in 1983, and subsequently intergeneric hybrids were produced in vitro by culture of F
1
immature embryo or young inflorescences. The calli were treated using colchicine, and the genome chromosomes in the intergeneric hybrids were doubled (2,3). Five hexaamphiploids (2n=6x=42,
AABBVV), TH1, TH1W, TH2W, TH3, and TH3W, were produced, and their agronomic traits and resistance were observed in 1986-1988. After 1988, a series of D. villosum derived wheat lines were produced by immature embryo and anther culture (Fig. 1).
These derived wheat lines were determined to be 6D/6V disomic substitution lines by cytogenetic analysis and in situ hybridization (3,15).
The pedigree of TH1 and TH1W is 81086A/ D. villosum , the pedigree of TH2W is
Stewarts 63/ D. villosum , and the pedigree of TH3 and TH3W is Mexicali 75/ D. villosum .
The pedigree of the 6D/6V derived lines is TH3/Wan 7107/2/Jimai 84-
5418*2/3/Shannong 7859. 810861A, Stewarts 63, and Mexicali 75 are T. durum lines
(2n=4x=28, AABB). Wan 7107, Jimai 84-5418, and Shannong 7859 are common wheat lines (2n=6x=42, AABBDD).
Plant materials. A total of sixty-eight wheat lines were used to test resistance to wheat powdery mildew, including one D. villosum accession No.1026 (2n=2x=14, VV), five amphiploids (2n=6x=42, AABBVV), eleven 6D/6V disomic substitution lines
(2n=6x=42, AABBDD'-6D/6V), two 6A/6V disomic substitution lines (2n=6x=42,
A'ABBDD-6A/6V), six 6AL/6VS translocation lines (2n=6x=42, A'ABBDD-6AL-6VS), thirty-one differential wheat lines constituting a differential resistance gene series from
Pm1 to Pm21 , six susceptible lines, and four parents of the 6D/6V lines.
The seeds of D. villosum accession No.1026, originated from the USSR. The five

119 amphiploids (AABBVV), one 6AL/6VS translocation lines, two 6A/6V disomic substitution lines, eleven 6D/6V disomic substitution lines, and their parents were provided by the third author. The seeds of five 6AL/6VS translocation lines, 92-R089,
92-R137, 92-R139, 92-R149, and 92-R178, were kindly provided by J. Johnson,
University of Georgia, Griffin, GA.
A series of segregating populations were developed from the crosses between
6D/6V disomic substitution lines and susceptible lines. An F
2
population derived from the cross of PM94460, a 6D/6V disomic substitution line, and 95N661, one of the 6A/6V substitution lines with the Pm21 gene, was developed for an allelism test.
Powdery mildew evaluation. Powdery mildew evaluations were performed using a detached leaf technique (8). Assessment of reaction was based on a descriptive scale of resistant (0-3), intermediate (4-6), and susceptible (7-9) reaction types (8). Two to five Bgt isolates, characterized for virulence, were used to test each segregating population.
Five F
2
populations also were tested for resistance to Bgt in a North Carolina State
University campus greenhouse. After inoculating with Bgt isolates in the laboratory, the same populations were transplanted in the greenhouse. The plants were grown individually and infected by a naturally occurring population. One month later, the plants were evaluated for powdery mildew reaction.
DNA Extraction and RAPD assay. Genomic DNA was extracted from fresh wheat leaves (6). The PCR procedure described by Williams et al. (1990) was followed with minor modifications (17). Each reaction consisted of 2.4 ul reaction buffer mix, 1.2 ul dNTPs (2.5m
M ), 5 ul primer (4 or 5 ng/ul), 0.2 ul Taq polymerase (5u/ul), 1.2 ul

120 unacetylated bovine serum albumen (BSA), and 5.0 ul (4 or 5 ng/ul) genomic DNA. A total of 41 cycles of PCR amplification were performed using a standard RAPD program with denaturation at 92 C for 1 min, annealing at 35 C for 1 min, and extension at 72 C for 2 min. The reactions were then visualized by electrophoresis on 1.2-1.5% agarose gels in 1X TBE.
Primer screening . Two methods were used to screen RAPD markers: (1) A total of 108 10-mer random primers were screened in a 6D/6V disomic substitution line,
PM930640, and all six of its pedigree parents, D . villosum , Mexicali 75, Wan 7107,
Shannong 7859, Jimai 84-5418, and TH3; (2) A total of 127 DNA samples, which were extracted from 127 F
2
individuals of Chancellor x PM930640, were pooled into two separate groups: R and S, for bulked segregant analysis. The R group consisted of 71
DNA samples from 71 F
2
individuals which were resistant to isolate Wkin 91, and the S group was composed of 56 DNA samples from 56 F
2
individuals which were susceptible to isolate Wkin 91. Another total of 110 10-mer random primers were used to screen for
RAPD markers in the two groups.
Linkage analysis. The 127 DNA samples, which were extracted from 127 F
2 individuals of Chancellor x PM930640, also were used to identify RAPD markers linked to the powdery mildew resistance gene in PM930640. Goodness-of-fit and independence tests were carried out using an P
2
statistic.
RESULTS
Disease reaction. D. villosum accession no. 1026 and its derived wheat lines were immune or highly resistant to all 37 tested isolates, but those of the T. durum and T.

121 aestivum parents were susceptible to more than ten isolates (data not shown). It is clear that the resistance in D. villosum has been successfully transferred into the derived wheat lines.
Six F
1
progenies derived from crosses between susceptible lines and 6D/6V disomic substitution lines were tested for resistance to five to seven Bgt isolates and all six F
1
progenies were highly resistant to all tested isolates and showed complete dominance (data not shown).
Segregation and inheritance. Nine F
2
populations derived from crosses between susceptible lines and seven 6D/6V disomic substitution lines were tested with two to five
Bgt isolates. However, the single gene expected ratio of 3R:1S (resistant : susceptible) was not found in most segregating populations for resistance to Bgt isolates, except in the
F
2
populations of PM94368 x Shannong 7859 and 95G22-1 x Yuandong 3 for resistance to isolate E
3
14 (Table 1). Four of the nine F
2
populations also were tested for resistance to a naturally occurring population of Bgt in the greenhouse. Again the segregation ratio did not fit a 3R:1S and a ratio close to a 1R:1S was found (Table 1).
Seven backcross BC
1
F
1
populations derived from crosses between susceptible lines and PM930640 were tested with four Bgt isolates . The segregation of resistant to susceptible individuals fit the 1R:1S of a single gene when the F
1
was crossed as a male, but did not fit a 1R:1S ratio and the number of resistant individuals was much lower than that of susceptible individuals when the F
1
was crossed as a female in the BC
1
F
1 populations of NK-Coker 68-15 x PM930640, and Saluda x PM930640 (Table 2).
However, the segregation of resistant to susceptible individuals was not in accordance with the 1R:1S of a gene expected ratio whether the F
1
was used as a male nor as a female

122 in the remaining two BC
1
F
1
populations, CA9211//PM95352/CA9211 and
PM95352/CA9211// CA9211 (Table 2).
Similarly, the BC
1
F
1
population derived from the cross between Chancellor and
PM930640 fit a 1R:1S ratio for only four of six isolates tested. The segregation was
1R:1S for resistance to isolates Flat 7-12, Wkin 91, #8 and E325, but not for W72-27 or the natural population in the greenhouse. The influence of the male of the cross was not clear since the BC
1
F
1
population resulted from a bulk where the F
1
was used both as a male and female (Table 2).
The inheritance of resistance to Bgt was also studied in a 6AL/6VS translocation line. The segregation of resistant to susceptible individuals was in accordance with a
3R:1S ratio for a single dominant gene in the F
2
population derived from a susceptible line, Y94077, and one 6AL/6VS translocation line, PM941181 (Table 1).
Allelism text. An allelism test between PM94460(6D/6V) and 95N661(6A/6V) with the gene Pm21 revealed that the resistance gene in the 6D/6V substitution line was
Pm21 . No susceptible individuals were observed in the F
2
population of PM94460 x
95N661 for resistance to four Bgt isolates, #8, 137a1, E
3
14, and E
3
25, or to the naturally occurring population of Bgt in the greenhouse of NCSU campus (Table 1).
RAPD markers. Six primers, OPAN03, OPAI01, OPQ05, OPAL03, OPAD17 and OPAG15, revealed polymorphisms and the polymorphic bands occurred at about
1700bp, 700bp, 1150bp, 750bp, 480bp, and 580bp, respectively in the 6D/6V substitution line PM930640 and its six pedigree parents (Fig. 2). The polymorphic bands from the six
RAPD markers, OPAN03
1700
, OPAI01
700
, OPQ05
1150
, OPAL03
750
, OPAD17
480, and
OPAG15
580
, were present in PM930640, D. villosum accession no. 1026 and TH3, which

123 carried chromosome 6V with the gene Pm21 , but absent in other four parents, Mexicali
75, Wan 7107, Shannong 7859, and Jimai 84-5418. Therefore, the six markers were associated with chromosome 6V and Pm21 . Three of the six markers, OPAN03
1700
,
OPAI01
700
, and OPAL03
750
, revealed polymorphisms in the F
2
population of Chancellor x PM930640 (Fig. 3). The linkage between these markers and the resistance gene, Pm21 , in PM930640 were analyzed (Table 3). Because the segregation of resistance to Bgt was not in accordance with a 3R:1S ratio for one single gene Pm21 , the markers did not fit a
3R:1S single locus segregation ratio in the F
2
population either, and the recombination frequency could not be accurately determined. However the cosegregation between Pm21 and the three markers did not fit a 9:3:3:1 ratio for two independent alleles (Table 3), and indicated the three markers were in fact linked to Pm21 .
Eight primers, OPA09, OPH09, OPH17, OPM02, OPK10, OPP03, OPV14, and
OPAI14, revealed polymorphisms in two groups: R and S, from bulked segregant analysis. The polymorphic bands in the four RAPD markers, OPA09
1000
, OPH09
1000
,
OPH17
1300
, and OPM02
820
, were present in the R group, and the other four markers,
OPAI14
1050
, OPK10
750
, OPP03
550
and OPV14
850
, were present in S group. Whether the eight markers were linked to Pm21 on chromosome 6V needs further study.
Five markers, OPAN03
1700
, OPAI01
700
, OPAL03
750
, OPAD17
480,
and OPAG15
580
, were evaluated for detecting Pm21 in fifty-nine wheat lines, including one D. villosum accession No.1026, six amphidiploids, five 6AL-6VS translocation lines, two 6A/6V disomic substitution lines, eleven 6D/6V disomic substitution lines, four parents of the
6D/6V derived lines, and twenty differential lines with known Pm genes from Pm1 to
Pm20 except Pm10,11,14, and 15 (Table 4). Two markers, OPAI01
700
and OPAN03
1700
,

124 were present in all the lines which carry chromosome 6V. The markers, OPAD17
480
and
OPAL03
750
, were observed in the 6A/6V and 6D/6V substitution lines alone. The marker, OPAG15
600
, was specific only for the 6D/6V substitution line. Currently, three groups of D. villosum derived wheat lines, 6AL-6VS translocation line, 6A/6V and
6D/6V substitution lines, have been developed. RAPD markers were shown to be useful in distinguishing the three type D. villosum derived wheat lines. One interesting primer,
OPAH11, revealed three markers, OPAH11
750
OPAH11
1750
, and OPAH11
1000
, and this single primer can be used to distinguish the three types of V genome lines among the seventeen wheat lines (Table 5).
DISCUSSION
The expression of resistance in the 6D/6V disomic substitution lines is complete and stable, and also can be genetically transferred to subsequent generations. This is clear since no segregation for resistance was observed in the 6D/6V derived wheat line selfed seeds. It also is clear that the resistance in these lines is controlled by a major gene, because we can classify the resistance into clearly resistant and susceptible individuals in the segregating populations. We did not find a expected 3R:1S ratio of resistant to susceptible individuals in the segregating populations to different Bgt isolates in the laboratory or the greenhouse. The ratio changed in the various parent backgrounds associated with different parents. It is interesting and needs further clarification why the segregation fit a 1R:1S ratio for one gene when the F
1 was crossed as a male, but did not fit a 1R:1S ratio when the F
1
was crossed as a female in the BC
1
F
1
populations of NK-
Coker 68-15 x PM930640, and Saluda x PM930640.
We were uncertain as to whether there were two genes for wheat powdery mildew

125 resistance which are located on the same chromosome 6V. The Pm21 in 6AL-6VS translocation lines and 6A/6V substitution lines originated from an accession of D . villosum that was introduced into China from Norwich Research Park, Colney, Norwich,
UK (1, 4,10). But the seeds of D. villosum accession No.1026, which was used as a donor of the 6D/6V derived wheat lines, originated from USSR. The awn color trait shows an obvious difference between them, the former is black and the latter is white.
The 6A/6V disomic substitution lines and 6AL/6VS translocation lines were developed by the use of normal crossing methods, but a series of 6D/6V disomic substitution wheat lines were produced utilizing immature embryo and anther cultures. Therefore, chromosome 6V in the 6D/6V disomic substitution lines has been altered from the 6V chromosome in the D. villosum .
Among the 21 loci for resistance to powdery mildew in wheat, Pm8 is located on the 1RS of 1BL-1RS and Pm17 on the 1RS of 1AL-1RS translocations (7,18). The two genes were all transferred into common wheat from rye ( Secale cereale ) and were located on same short arm of chromosome 1R, but two gene symbols were proposed since the resistance in the 1BL-1RS and 1AL-1RS translocation lines had different expressions.
Now, three groups of D. villosum derived wheat lines, the 6AL-6VS translocation line, the 6A/6V substitution line, and the 6D/6V substitution line, have been developed
(1,3,10,15). The symbol, Pm21 , has been proposed to the powdery mildew resistance gene in the 6AL-6VS translocation lines (1,13,14). In this study, we found that RAPD markers revealed different polymorphisms among the three D. villosum derived lines.
The three groups of D. villosum derived wheat lines can been distinguished not only by cytogenetic analysis but also by RAPD markers, and they can been used in wheat

126 breeding for various purposes. Therefore, we suggest naming symbols, Pm21a, Pm21b, and Pm21c to the corresponding resistance gene in the 6AL-6VS, 6A/6V, and 6D/6V sources, respectively.
Eight RAPD markers, OPM09
850
, OPF14
974
, OPD16
1375
, OPM02
1400
, OPB08
1450
,
OPJ10
1500
, and OPH17
1900
, have be identified associated with Pm21 gene (6AL-6VS)
(12,14). In this research, more than ten markers were identified to be associated with the chromosome 6V and the gene Pm21 . These markers may be used in mapping chromosome 6V and for marker-assisted selection of Pm21 for wheat powdery mildew resistance.
The accession No.1026 of D. villosum and its derived wheat lines not only showed immune or highly resistant reactions to Bgt , but also were resistant to all tested
Bgt isolates. Therefore, these D. villosum derived wheat lines can provide new sources of resistance to wheat powdery mildew for wheat breeding.

LITERATURE CITED
127
1. Chen, P. D., Qi, L. L., Zhou, B., Zhang, S. Z., and Liu, D. J. 1995. Development and molecular cytogenetic analysis of wheatHaynaldia villosa 6VS/6AL translocation lines specifying resistance to powdery mildew. Theor. Appl. Genet. 91:1125-1128.
2. Chen, X., and Huang, H. 1991. Genetic studies on the ADH and esterase isozymes in
T. durum , H. villosa and it synthetic amphidiploids. Acta Phytopathologica Sinica
17:123-127
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1996. Transfer of gene resistance to powdery mildew from H. villosum to common wheat by tissue culture. Scientia Agricultura Sinica 29(5):1-8.
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of Haynaldia villosa on powdery mildew isolate and its expression in wheat
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T. 1988. Biochemical versatility of amphiploids derived from crossong Dasypyrum
villosum (L.) Cabdargy and wheat: Genetic control and phenotypical aspects. Theor
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7. Heun, M., Friebe, B., and Bushuk, W. 1990. Chromosomal location of the powdery
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cultivars of soft red winter wheat. Plant Dis. 74:747-752.

128
9. Linde-Laursen, I., Jensen H. P., and Jorgensen, J. H. 1973. Resistance of Triticale ,
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Transfer of Haynaldia villosa chromosomes into Triticum aesticum . Pages 355-361 in: Miller, T. E., Koebner, R. M. D (ed.), Proceedings of 7 th
Int. Wheat Genet. Symp.,
Cambridge, UK.
11. Murray, T. D., De La Pena, R. C., Yildirim, A., and Jones, S. S. 1994. A new source of resistance to Pseudocercosporella herpotrichoides , cause of eyespot disease of wheat, located on chromosome 4V of Dasypyrum villosum . Plant Breed. 113:281-286.
12. Qi, L.L., Liu, D. J., Chen, P. D., Cao, M. S., Hui, D. W., and Chen, S. Y. 1993.
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130
Table 1. Segregation of resistance to two to five isolates of Blumeria graminis f. sp . tritici in eleven F
2
populations
________________________________________________________________________
Cross
No. of individuals
Isolate Resistant Susceptible
 2
(3:1)
________________________________________________________________________
Chancellor/PM930640 Flat7-12 97 80 38.510**
Wkin91
W72-27
101
114
76 30.375**
63 10.593**
#8 93
E
3
25 98 greenhouse/natural 69
77 37.341**
79 36.386**
65 39.493**
NK-Coker 68-15/PM930640
Saluda/PM930640
PM95364/CA9211
95G32-1/Wan 7107
Wkin91
209a2
#8
Wkin91
209a2
E
3
25
163
163
163
129
131
58
Flat7-12
E
3
25
73
73
#8
E
3
14
73
73 greenhouse/natural 40
171
171
171
122.255**
122.255**
122.255**
115 63.738**
113 59.104**
87 94.733**
63 32.980**
63 32.980**
63 32.980**
63 32.980**
33 15.895**
95G22-1/Yuandong 3 Wkin91
E
3
14
59
62
33
30
5.797*
2.841
#8
E
3
25
49
44
43
48
23.188**
36.232**
_______________________________________________________________________
Table 1. Continue

131
_______________________________________________________________________
137a1 44 greenhouse/natural 37
48
42
36.232**
33.422**
PM94368/Shannong 7859
CA9211/PM94460
E
3
25
E
3
14
#8
209a2
109
77
81
77
Wkin91 77 greenhouse/natural 73
44 1.153
27 0.051
21 1.059
89 72.490**
97 87.732**
79 58.982**
PM95352/CA9211
Y94077/PM941181
#8
Wkin91
Wkin91
209a2
101a2
68
68
71
73
73
163
163
255.759**
255.759**
25 0.056
23 0.056
23 0.056
PM94460(6D/6V)/95N661(6A/6V) #8
137a1
160
160
0
0
E
3
14
E
3
25
160
160 greenhouse/natural 152
0
0
0
_______________________________________________________________________ a ** Significant at the 0.01 probability level.

132
Table 2. Segregation of resistance to two to five Bgt isolates in seven BC
1
F
1
populations
________________________________________________________________________
Cross
No. of individuals
Isolate Resistant Susceptible
 2
(1:1)
________________________________________________________________________
PM930640/NK-Coker 68-15
//NK-Coker 68-15 Wkin91
209a2
#8
E
3
25
25
30
25
25
49 7.784**
42 2.000
49 7.784**
49 7.784**
NK-Coker 68-15//
PM930640/ NK-Coker 68-15
PM930640/Saluda//Saluda
Saluda//PM930640/Saluda
PM95352/CA9211//CA9211
CA211//PM95352/CA9211
Wkin91
209a2
#8
E
3
25
209a2
Wkin91
209a2
Wkin91
209a2
Wkin91
209a2
43
43
43
43
5
5
65
60
7
7
3
45 0.045
45 0.045
45 0.045
45 0.045
29
29
48
53
23
23
16
16.941**
16.941**
2.558
0.434
8.533**
8.533**
8.895**
Wkin91 3
Chancellor*2/PM930640 Flat7-12 33
Wkin91
#8
W72-27
E
3
25
41
27
50
27 greenhouse/natural 25
16
39
8.895**
0.500
31 1.389
42 3.216
21 11.845**
42 3.216
45 5.714*
_______________________________________________________________________ a
** Significant at the 0.01 probability level.

133
Table 3. Cosegregation of Pm21 resistance to isolate Wkin 91 of Bgt and RAPD markers,
OPAN03
1700
, OPAI01
700
, and OPAL03
750
, in Chancellor/PM930640 F
2
population.
_______________________________________________________________________
Locus Phenotype
 2
A
 2
B
 2
AB
A B RM Rm SM Sm (3:1) (3:1) (9:3:3:1)
_______________________________________________________________________
Pm21 OPAN03
1700
70 1 6 50 24.696** 15.562** 258.106**
Pm21 OPAI01
700
70 1 6 50 24.696** 15.562** 258.106**
Pm21 OPAL03
750
70 1 6 50 24.696** 15.562** 258.106**
_______________________________________________________________________ a **Significant at the 0.001 probability level. b
Phenotype: RM = powdery mildew resistant and presence of the RAPD marker, Rm =
powdery mildew resistant and absence of the marker, SM = powdery mildew
susceptible and presence of the marker, and Sm = powdery mildew susceptible and
absence of the marker.

Table 4. RAPD markers for detecting Pm21 in forty-nine wheat lines.
______________________________________________________________________________________________________
Line Gene Location OPAI01
700
OPAN03
1700
OPAL03
750
OPAD17
480
OPAG15
580
______________________________________________________________________________________________________
Mexicali 75 ? - - - - -
Wan 7107
Jimai 84-5418
Shannong 7859
D. villosum
TH1
TH1W
TH2W
TH3
?
?
?
Pm21
Pm21
Pm21
Pm21
Pm21
6V
6V
6V
6V
6V
-
-
-
+
+
+
+
+
-
-
-
+
+
+
+
+
-
-
-
+
+
+
+
+
-
-
-
+
+
+
+
+
-
-
-
+
+
+
+
+
TH3W
PM941181
92-R089
92-R137
92-R139
92-R149
92-R178
95N661
Pm21
Pm21a
Pm21a
Pm21a
Pm21a
Pm21a
Pm21a
Pm21b
6V
6AL-6VS
6AL-6VS
6AL-6VS
6AL-6VS
6AL-6VS
6AL-6VS
6A/6V
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
-
-
+
-
-
-
-
+
-
-
+
-
-
-
-
-
-
-
+
-
95N668
94G22-1
94G32-1
95G10
95G59
93N115
Pm21c
Pm21c
6D/6V
6D/6V
+
+
+
+
+
+
+
+
+
+
93N40 Pm21c 6D/6V + + + + +
________________________________________________________________________________________________________
Table 4. Continue
Pm21b
Pm21c
Pm21c
Pm21c
6A/6V
6D/6V
6D/6V
6D/6V
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
134

135
________________________________________________________________________________________________________
PM930640
PM94460
PM94368
PM95364
Pm21c
Pm21c
Pm21c
Pm21c
6D/6V
6D/6V
6D/6V
6D/6V
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
PM95352
Chancellor (Cc)
Axminter/8*Cc
Ulka/8*Cc
Asosan/8*Cc
Chul/8*Cc
Sonora/8*Cc
Khapli/8*Cc
Ronos
Kormoran
TP114
Transec
Kavkaz
Normandie
Pm21c
None
Pm1
Pm2
Pm3a
Pm3b
Pm3c
Pm4a
6D/6V
7AL
5DS
1AS
1AS
1AS
2AL
Pm4b 2AL
Pm5
Pm6+1
Pm7
7BL
2B+5DS
4BS/5R
Pm8 1BL-1RS
Pm9+1+2 7AL
+
-
-
-
-
-
-
-
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
+
-
Line #31 Pm12
T. longissimum derivatives Pm13
BRG 3N
Amigo
Pm16
Pm17
6BS-6SS.6SL
3B, 3D
4A
1AL-1RS
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
M1N Pm18
D85350 Pm19
TAM 10/Thatcher Pm20
7A
7D
6BS-6RL
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
____________________________________________________________________________________________________________ a
'+' = the band present, and '-' = the band absent.

136
Table 5. One primer OPAH11 with its three RAPD markers in seventeen wheat lines
_______________________________________________________________________
Line Genome OPAH11
750
OPAH11
1750
OPAH11
1000
Mexicali 75 AABB
Wan 7107 AABBDD
Jimai 84-5418 AABBDD
Shannong 7859 AABBDD
TH3 AABBVV
D. villosum VV
+ + -
-
-
-
+
-
- -
- -
- -
+ +
- +
PM930640
94G22-1
PM9446
PM94368
96N661
95N668
PM941181
AABBDD'(6D/6V)
AABBDD'(6D/6V)
AABBDD'(6D/6V)
AABBDD'(6D/6V)
A'ABBDD(6A/6V)
A'ABBDD(6A/6V)
A'ABBDD(6AL/6VS)
+ + -
+ + -
+ + -
+ + -
- - +
- - +
- - +
95N665
92-R137
92-R139
92-R178
A'ABBDD(6AL/6VS)
A'ABBDD(6AL/6VS)
A'ABBDD(6AL/6VS)
A'ABBDD(6AL/6VS)
-
-
-
-
- +
- +
- +
- +
_______________________________________________________________________ a
'+' = the band present, and '-' = the band absent.

137
Fig.1 Transfer of wheat powdery mildew resistance from D. villosum to T. aestivum
1983 Triticum durum x Dasypyrum villosum
(AABB) | (VV)

1984-85 F
1
(ABV)
| immature embryo culture
| anther culture
| colchicine

1986-88 Amphiploids: TH1, TH1W, TH2W, TH3, TH3W
(AABBVV)
1988 TH3 x Wan7107
(AABBVV) | (AABBDD)

1988-89 F
1
x Jimai 84-5418
| (AABBDD)

three way F
1
x Jimai 84-5418
| (AABBDD)
| immature embryo culture

1990 BC
1
F
1
x Shannong 7859
(HV90304) | (AABBDD)
| immature embryo culture

SC1: HV90940, HV90941
SC1: HV90940 SC1: HV90941
 
1991-92 SC3

SC2: N91068 SC3

SC2: N91204
|

anther culture |

DH1

1993 SC4

SC5

SC4: 93N115, 93N40
(93N235) DH2: PM930640 | |
anther culture
  
anther culture

1994 DH2

DH1 DH3: PM94460, PM94368 DH1 94G32-1
| 94G22-1 | |
   
1995 DH3: PM95352 95G10 DH2: PM95364 95G59

138
OPAN03 OPAL03 OPAI01
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7

 
Fig. 2 Amplification patterns of DNA from PM930640 and its six pedigree parents: 1.
D . villosum , 2. Mexicali 75, 3. Wan 7107, 4. Shannong 7859, 5. Jimai 84-5418, 6. TH3, and
7. PM930640.
M R R R R R R R R R R R R R R S S S S S S S S S S S S S S M
(a)
750bp

(b)
1700bp

M R R R R R R R R R R R R R R S S S S S S S S S S S S S S M
Fig. 3. Amplification patterns of DNA detecting (a) OPAL03
750 and (b) OPAN03
1700
RAPD fragments in Chancellor/PM930640 F
2
individuals. R = resistant individual and S
= susceptible individual in the F
2
population. Lane M is a 1-kb molecular-weight marker.