Research Highlights of the CIMMYT Wheat Program 1999-2000

solutions with high aluminum levels
(CMBW91M02016S-0M-040Y-1AL-2AL-7Y-0M-3SJ-0Y).
• Most FHS resistance sources noted also convey
maintenance of a low toxin level in the grain despite
fungal infection.
• The advanced wheats listed are also resistant to the
three common rusts plus Septoria tritici.
Abiotic stress tolerance
One of the key abiotic constraints to production in
high rainfall areas is the high amount of rain that falls
on the maturing wheat crop. Excess rain causes the
grain to start germinating before it is harvested, which
compromises end-use quality due to the undesirable
proteins produced during germination. High rainfall
wheats should possess sprouting tolerance to
counteract this problem. Intermediate levels of
sprouting tolerance are available, mostly in redgrained
wheats, but higher levels are being sought.
Table 4 lists both red- and white-grained wheat lines
combining excellent sprouting tolerance with
acceptable yield and industrial quality.
These lines were selected from a Mexico/Australia
shuttle breeding effort. In Mexico the planting date
was adjusted so that grain-filling would coincide with
peak seasonal rainfall in Toluca; this caused sprouting
Table 4. Red- and white-grained lines having high levels of
sprouting tolerance in combination with acceptable yield (relative
to the check variety Prinia) and end-use quality (loaf volume).
Yield Grain Loaf
Cross Selection history Prinia % color volume
TUI/CLMS N91.358-3WM-102AUS-5WM- 102 Red 1025
010WM-010Y-010M-10Y-0Y
HAHN/PRL//CLMS/ N92.240-2WM-60AUS-2WM- 91 White 875
3/HAHN/PRL 010WM-010Y-010M-2Y-0Y
TUI//2*SUNCO/ N92.241-1WM-71AUS-6WM- 102 Red 900
SA1166/3/TUI 010WM-010Y-010M-9Y-0Y
Table 5. New lines showing high levels of industrial quality
during the 2000 crop cycle (MV-00), Toluca, Mexico.
Use W Flour
Cross Selection history type value P/L protein
MILAN/TUI CMSS95Y02595S-0100Y-0200M- 1a* 785 0.9 12.7
2Y-010M-5Y-030M-1PZ-0Y
TNMU/MILAN CMSS95Y02037S-0100Y-0200M- 1a 660 0.7 12.8
14Y-010M-1Y-030M-1PZ-0Y
MILAN//PSN CMSS95Y02329S-0100Y-0200M- 1a 536 0.8 12.9
/BOW 9Y-010M-9Y-030M-3PZ-0Y
* Use-type 1a = ideal dough strength and extensibility with high protein levels.
in sensitive segregants. In Australia the
populations were exposed to artificial excess
moisture in a controlled environment, again
permitting identification of desired tolerant
genotypes. The sources of sprouting tolerance
were Columbus and Sunco/SA1166.
Industrial quality
Industrial quality must be a key consideration
when choosing parents. If the proper
complementary genes are not introduced during
hybridization, they cannot be expected to turn
up in the progeny. Once the proper genes have
been introduced, it has become increasingly
evident that not much needs to be done in regard
to selection for industrial quality until advanced
lines appear. Apparently these genes transmit
themselves well through segregating
populations, so that a sufficient number of high
quality lines will emerge in the F7.
Several lines showed very high levels of
industrial quality during the last Toluca crop
cycle (Table 5). The quality values of these lines
are in fact among the highest one could expect to
obtain (W values above 500) while maintaining
high protein levels.
The 446 most outstanding lines from the recent
ME2 yield trials have been entered into the most
recent issue (10 th ) of the international nursery
High Rainfall Wheat Screening Nursery (10 th
HRWSN). The new entries express high yield as
well as resistance to stem, leaf, and stripe rusts,
and Septoria tricici, plus a certain level of
resistance to Fusarium head scab.
Of the 446 entries, 101 (23%) have so-called
group 1 quality (balanced, strong, extensible); 76
(17%) of these actually show 1a type quality
(balanced, strong, extensible, but with protein
levels above 12%), the highest bread making
quality level attainable. Such high quality wheat
is used mostly for blending purposes (i.e., to
correct inferior flour). An additional 67 entries
(15%) have group 2 quality, representing good
bread making quality.
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