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allowed interspecific and intergeneric cross combination products to define several
entries that were similar to or better than Sumai 3; better in the sense that the in-
oculated florets in the middle of the spike did not damage the seed formation com-
pletely as happens with Sumai 3. Two groups with potent resistance were selected
and one set is of the D genome synthetics (Zaharieva et al.
2003
) and another that
has pyramided resistance from a intergeneric combination combined with a primary
synthetic. The former SH group formed a sub-set with 35 primaries and the latter
a few sister lines with extended details to cover all 4 categories of evaluation from
type 1 to 4 and then evaluated for multiple stresses (Mujeeb-Kazi et al.
2004
)
SeptoriaLeafBlotch
Septoria leaf blotch (
Bipolaris sorokiniana
) limits wheat production in high rain-
fall areas across 10.4 × 10
6
hectares globally. Disease scoring is of a double-digit
scale from 1-1 (resistant) to 9-9 (susceptible) and recorded over the three grain
development stages (watery, milky, doughy). The D genome synthetics proved to
be superior for their resistance levels with numerous giving scores between 1-1 and
3-1 compared to the bread wheat cultivars that exhibited a susceptible trend with
scores between 4-1 and 9-9. The identification of resistance in unique SH sources
led breeders to exploit the germplasm in their wheat improvement efforts. The de-
rivatives allowed for selection of good agronomic plant progenies with high levels
of resistance and also led to germplasm registrations (Mujeeb-Kazi et al.
2000
,
2001a
). Similar resistance was also observed in the A genome synthetics (AAB-
BAA) where the score range of 1-1-2-1 in abundance were superior to the levels
seen for their durum parents that had the best at 4-1 to poor forms reaching 8-9.
Recently, Aggarwal et al. (
2011
) developed a SCAR marker for detection of spot
blotch in leaf and field soil which is suggested to play a key role in effective man-
agement of this disease.
CochliobolusSpotBlotch
Spot blotch affects wheat crops across several environments from Latin America,
Asia and southeast Asia with Bangladesh being represented as a major disease loca-
tion. Its presence in the wheat crop cycle of 2009-2010 in lower Punjab of Pakistan
was alarming causing a leading cultivar “Bhakkar” to be banned from further plant-
ing in that area. The screening site for this disease is the most severe in Mexico at
the location “Poza Rica” where field screening under natural conditions allowed nu-
merous entries to be selected with resistance that included genetic stocks of various
genomes and their advanced pre-bred derivatives. The best resistant lines selected
were later called “Mayoor” and “Sabuf” leading to crop registration (Mujeeb-Kazi
et al.
1996b
). Subsequently when focus shifted to exploitation of close wheat pro-
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