TY - JOUR
T1 - The WtmsDW locus on wheat chromosome 2B controls major natural variation for floret sterility responses to heat stress at booting stage
AU - Erena, Million F.
AU - Lohraseb, Iman
AU - Munoz-Santa, Isabel
AU - Taylor, Julian D.
AU - Emebiri, Livinus C.
AU - Collins, Nicholas C.
N1 - Funding Information:
ME was a recipient of a University of Adelaide ASI scholarship. This work was supported by the Grains Research and Development Corporation (GRDC) Project UA00147, the Australian Research Council (ARC) project LP150100694, NSW-DPI, the NSW BioFirst Initiative Project 2 SAP E2985, and the Australian Centre for Plant Functional Genomics, funded by the ARC, the GRDC and the South Australian Government.
Publisher Copyright:
© Copyright © 2021 Erena, Lohraseb, Munoz-Santa, Taylor, Emebiri and Collins.
PY - 2021/3/29
Y1 - 2021/3/29
N2 - Heat stress at booting stage causes significant losses to floret fertility (grain set) and hence yield in wheat (Triticum aestivum
L.); however, there is a lack of well-characterized sources of
tolerance to this type of stress. Here, we describe the genetic analysis
of booting stage heat tolerance in a cross between the Australian
cultivars Drysdale (intolerant) and Waagan (tolerant), leading to the
definition of a major-effect tolerance locus on the short arm of
chromosome 2B, Wheat thermosensitive male sterile Drysdale/Waagan (WtmsDW). WtmsDW
offsets between 44 and 65% of the losses in grain set due to heat,
suggesting that it offers significant value for marker-assisted
tolerance breeding. In lines lacking the WtmsDW tolerance allele,
peaks in sensitivity were defined with reference to auricle distance,
for various floret positions along the spike. Other (relatively minor)
floret fertility response effects, including at the Rht-D1
dwarfing locus, were considered likely escape artifacts, due to their
association with height and flowering time effects that might interfere
with correct staging of stems for heat treatment. Heat stress increased
grain set at distal floret positions in spikelets located at the top of
the spike and increased the size of spikelets at the base of the spike,
but these effects were offset by greater reductions in grain set at
other floret positions. Potentially orthologous loci on chromosomes 1A
and 1B were identified for heat response of flowering time. The
potential significance of these findings for tolerance breeding and
further tolerance screening is discussed.
AB - Heat stress at booting stage causes significant losses to floret fertility (grain set) and hence yield in wheat (Triticum aestivum
L.); however, there is a lack of well-characterized sources of
tolerance to this type of stress. Here, we describe the genetic analysis
of booting stage heat tolerance in a cross between the Australian
cultivars Drysdale (intolerant) and Waagan (tolerant), leading to the
definition of a major-effect tolerance locus on the short arm of
chromosome 2B, Wheat thermosensitive male sterile Drysdale/Waagan (WtmsDW). WtmsDW
offsets between 44 and 65% of the losses in grain set due to heat,
suggesting that it offers significant value for marker-assisted
tolerance breeding. In lines lacking the WtmsDW tolerance allele,
peaks in sensitivity were defined with reference to auricle distance,
for various floret positions along the spike. Other (relatively minor)
floret fertility response effects, including at the Rht-D1
dwarfing locus, were considered likely escape artifacts, due to their
association with height and flowering time effects that might interfere
with correct staging of stems for heat treatment. Heat stress increased
grain set at distal floret positions in spikelets located at the top of
the spike and increased the size of spikelets at the base of the spike,
but these effects were offset by greater reductions in grain set at
other floret positions. Potentially orthologous loci on chromosomes 1A
and 1B were identified for heat response of flowering time. The
potential significance of these findings for tolerance breeding and
further tolerance screening is discussed.
KW - auricle distance
KW - floret sterility
KW - heat tolerance
KW - male sterility
KW - QTL
KW - wheat
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U2 - 10.3389/fpls.2021.635397
DO - 10.3389/fpls.2021.635397
M3 - Article
C2 - 33854519
AN - SCOPUS:85104189981
VL - 12
SP - 1
EP - 14
JO - Frontiers in Plant Science
JF - Frontiers in Plant Science
SN - 1664-462X
M1 - 635397
ER -