Biology Reference
In-Depth Information
Compared to other abiotic stresses such as
salinity or drought, relatively few QTLs (apart
from the SUB1 locus) for submergence toler-
ance in rice have been reported. In one of the
most detailed studies, Toojinda and colleagues
(2003) reported QTLs on chromosomes 1, 2, 5,
7, 10, and 11 using five phenotypic measure-
ments and two donors (FR13A and Jao Hom
Nin). In an earlier study, selective genotyping
was used to identify QTLs on chromosomes 6,
7, 11, and 12 (Nandi et al. 1997). However, since
primarily amplified fragment length polymor-
phism (AFLP) markers were used, it is difficult to
determine QTL positions accurately. A summary
of previously detected QTLs for submergence
tolerance is shown in Figure 2.4. Apart from
searching for and validating minor QTLs from
FR13A, the research focus at IRRI is currently
on using highly adapted sources, including IR72,
in which a major QTL was identified on the long
arm of chromosome 1 (Septiningsih et al. 2012),
IR64, and IRRI 105 (PSB Rc18), since more
1
2
4
5
6
RM307
RM537
RM499
RM485
RM133
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
RM507
RM153
RM551
RM401
RM279
RM555
RM174
RM550
RM510
RM84
RM272
RM413
RM437
RM289
RM169
RM509
RM164
RM173
RM188
RM233B
RM26
RM538
RM334
RM261
RM185
RM142
RM402
RM276
RM136
RM452
RM600
RM23
RM81A
RM140
RM301
RM465
RM3
RM341
RM475
RM24
RM129
RM594
RM273
RM241
RM317
RM595
RM493
RM5
RM246
RM162
RM106
RM221
RM237
RM340
RM103
RM573
RM128
RM212
RM102
RM315
RM104
RM318
RM6
RM425
RM208
RM559
RM213
7
8
9
10
11
12
RM436
RM427
RM408
RM337
RG757
RM285
RM219
0
10
20
30
40
50
60
70
80
90
100
110
120
130
RM474
RM222
RM216
RM311
RM415
RM286
RM332
RM120
RM441
RM202
RM536
RM209
RM21
RM239
RM214
RM542
RM247
RM512
RM101
RM519
RM309
RM463
RM270
RM2
RM500
RM409
RM410
RM257
RM160
RM467
RM184
RM11
RM182
RM10
RM455
RM234
RM18
RM118
RM310
RM547
RM331
RM284
RM210
RM531
RM484
RM147
RM590
RM429
RM149
RM477
RM206
RM420
RM172
RM502
RM205
RM447
RM264
Fig. 2.4. Consensus QTL map for submergence tolerance. Linkage maps are derived from “anchor” SSR markers (i.e.,
common to both maps) from the “Cornell SSR 2001” and “CIAT SSR 2006” ( www.gramene.org; Temnykh et al., 2000;
Orjuela et al., 2010). Chromosome 3 is not shown because no QTLs have been detected on this chromosome. Anchor SSRs
are indicated in bold and larger font; other markers are from the Cornell SSR 2001 map only, using genetic map distances.
SUB1 is shown on chromosome 9. Approximate QTL positions are represented from Toojinda et al. (2003; “TKU”), Nandi
et al. (1997; “NIR”), and Septiningsih et al. (2012). Filled QTL bars indicate QTLs that were detected in multiple populations
and/or component traits, whereas hatched QTL bars indicate minor QTLs detected in only single population or using a single
component trait. Box plot QTL bars are indicated for QTLs from Nandi et al. (1997). QTL positions could only be estimated
due to the low number of SSRs used in this study. Possible QTLs overlapping between studies were detected on chromosomes
7 and 11. The figure was produced using MapChart 2.1 (Voorrips, 2002). For a color version of this figure, please refer to the
color plate.
 
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