QTL characterization of a synthetic hexaploid wheat-derived line for Fusarium head blight resistance Xinyao He1,2, Morten Lillemo2, Jianrong Shi3, Åsmund Bjørnstad2, Tatiana Belova2, Susanne Dreisigacker1, Etienne Duveiller1, Pawan K. Singh1 1
International Maize and Wheat Improvement Center (CIMMYT), El Batán, Mexico; 2 Norwegian University of Life Sciences, Ås, Norway; 3 Jiangsu Academy of Agricultural Sciences, Nanjing, China
E-mail address:
[email protected]
Introduction
Results and discussion
Fusarium head blight (FHB) is a devastating disease of wheat with global importance, causing not only yield loss but also mycotoxin contamination of food and feed. QTL mapping of resistant germplasm can help identify molecular markers for use in resistance breeding. CIMMYT has developed numerous FHB resistance breeding lines (He et al. 2013), among which Shanghai3/Catbird (SHA3/CBRD) was characterized in a previous study and the results indicated a major QTL on 2DLc and several minor QTL, often associated with anther extrusion (AE) or plant height (PH) (Lu et al. 2013). To validate resistance QTL and their association with morphological traits and flowering biology, another mapping population was developed using the resistant parent Soru#1 with Shanghai-3 (SHA3, a Chinese breeding line with high level of FHB resistance) in the pedigree and the susceptible parent Naxos as in Lu et al. (2013).
• In spray and spawn experiments, PH and DH often showed moderately negative correlations with FHB traits, whereas AE exhibited only marginal correlations with FHB traits. • In spray and spawn experiments, two major QTL for FHB traits were found on 2DLc and 5AL, respectively (Figure 1), and a minor QTL was identified on 2DL. Putative QTL were also detected on chromosomes 2AS, 4AL, 4DS and 5DL. Many of the QTL were the same as in Lu et al. (2003), but showed much better resolution. • In point inoculated experiments, QTL on 2DS, 3AS, 4AL and 5AL were identified, but none was repeatable across environments. • When PH and DH were used as covariates, QTL on 4AL and 4DS disappeared and that on 5AL at Vrn-A1 was significant only in 2011 for FHB and DON. The ones on 2DLc and 2DL remained significant and three new putative QTL were detected on 2AS, 4DS and 5DL, respectively (Table 1). • The resistance of ‘Soru#1’ to FHB was mainly of Type I, and QTL for DH, PH, and AE often coincided with those for FHB traits, indicating that phenological and morphological traits and flowering biology play important roles in wheat’s resistance to or escape from FHB. • SNPs tightly linked to resistance QTL, particularly 2DLc, could be to transfer or select for those QTL.
Materials and methods • An FHB resistant synthetic wheat-derivative ‘Soru#1’ (SABUF/5/BCN/4/RABI//GS/CRA/3/AE.SQUARROSA [190], in which SABUF has a pedigree of SHA3//BUC/FLK) was hybridized with a German cultivar ‘Naxos’ to generate 131 recombinant inbred lines (RIL). • We phenotyped for FHB and associated traits in spray inoculated experiments at El Batán, Mexico; spawn inoculated experiments in Ås, Norway; and point inoculated experiments in Nanjing, China; with two field trials at each location.
29
BS00079189_51
42
wC11_c951_572693
55 61
gwm304 Ex_c60370_688
71
tplb0039m09_92
81
Ex_c97639_173
91
wExc39592_46849607
20
BS00031073_51
15
19
10
Ex_c47920_249
5
0
10
wExc1880_3545329 IAAV7827 Td_c13810_485 BS00028356_51 Kukri_c14187_243 wExc31154_39982416 wExc2441_4568016
243 246 255 258
wmc727 CAP8_c671_588 gwm291 BS00067816_51
TGm
198 202 203 214 219 223 232
AEm
w_Ku_c40349_48594583 Vrn-A1 Ex_c31769_793 IAAV4799 Bw_c3675_788
PHm
157 167 171 175 184
PHm
K_r_c70839_205
DHm
146
DHm
Ex_c2113_1475
FHBspawn
Ex_c35676_288 Ku_c13130_1319
134
FDKspray
192 198
RAC875_c49940_385 gwm617 Td_c64337_243
FDKspray
RAC875_c4196_1689
111 120 124
FHBpoint
177
Td_c47852_422
DONspray
164
100
FHBspray
163
BS00021881_51 GENEU3588_374 Kukri_c31995_1948
FDKspray
gwm301
58
AEm
140
57
AEm
66 82 84 102 117 127
D_GBUVXFX02GQVQX_189 Kukri_c36639_186 RFL_c3172_444 Ex_c8573_291 Bw_c3871_903 Ex_r_c116627_114 BS00023133_51 Kukri_c25716_284 R875r_c102601_204 gwm539 GENEU0808_728 wC11_r_c4111_1943520 Ex_c7282_512 Ex_r_c103684_815 Ex_c81356_316 D_GDS7LZN02FDZX8_269 gwm349 Kukri_c18971_279 D_GBUVXFX02XUXG0_432
DONspray
51
DONspray
wExc25311_34578436
FHBspray
37
FHBspray
Kukri_c55028_182
56
0
R875r_c72220_143
25
55
5
10
BS00080749_51
FHBspawn
Table 1. QTL for FHB traits after spray and spawn inoculation in the Soru#1 x Naxos population and their association with other traits.
0
FHBspawn
• QTL mapping was carried out with MapQTL v6.0 using two strategies: 1) MQM for FHB parameters without covariates; and 2) MQM with days to heading (DH) and PH as covariates.
Chr_5A
Chr_2D 0
• Genotyping was done with the Illumina iSelect 90K wheat chip, along with SSR and STS markers linked to known FHB resistance QTL.
Figure 1 QTL for FHB parameters and associated traits on chromosomes 2D and 5A.
References
The percentage of explained phenotypic variation in the multiple regression models is shown. QTLs are listed if they were over the LOD threshold of 3 (in bold) in at least one environment. # denotes QTL calculated with DH and PH as covariates N Naxos, S Soru #1, AE anther extrusion, PH plant height, DH days to heading
He X, Singh PK, Duveiller E, Dreisigacker S, Singh RP (2013). Development and characterization of International Maize and Wheat Improvement Center (CIMMYT) germplasm for Fusarium head blight resistance. In: Alconada TM, Chulze SN (eds) Fusarium Head Blight in Latin America. pp 241-262. Lu Q, Lillemo M, Skinnes H, He X, Shi J, Ji F, Dong Y, Bjornstad A (2013). Anther extrusion and plant height are associated with Type I resistance to Fusarium head blight in bread wheat line 'Shanghai-3/Catbird'. Theor Appl Genet 126:317-334.
