The Eleventh Regional Wheat Workshop For Eastern ... - Cimmyt

Germplasm enhancement through molecular breeding - Harjit Singh et al.
Sharma, H.C. and B.S. Gill. 1983. Current status of wide hybridization in wheat. Euphytica, 32: 17-31.
Singh, 1., Sukhija, P.K., Harjit- Singh, Dhaliwal, H.S. and K.S. Gill. 1991. Source of resistance to cereal cyst
nematode (Heterodera avenae) in wild Triticum and Aegi/ops species. Ind. 1. Nematol, 21: 145-148.
Questions and Answers:
Ravi P. Singh: Most wide cross programs look for chromosome segments as small as
possible worrying about undesirable traits that may be present in the longer segments. I
suggest that all transfers, even longer ones, must be maintained and perhaps evaluated for
genes other than the targeted resistance genes.
Answer: All interspecific derivatives carrying large alien segments as well as those with
complete substituted/added alien chromosomes are being maintained and evaluated for other
desirable traits. However, for effective commercial utilization of alien genes with minimum
linkage drag, one needs to select for small alien segments.
Table 1.
Wide hybridization for transfer of desirable traits from wild Triticum and
Aegi/ops species.
No of
Donor species with sources Recurrent
genome(s) Character(s) utilized parent
Triticum urartu (AU) - Stripe rust* 1 T durum
- New HMW subunits (Ax + Ay) 3 - do-
T boeoticum (A b ) - New HMW subunits (Ax + Ay) 2 T. durum
­
T araraticum (AG) - Leaf rust 6 T durum
- Stripe rust 2 - do
- Powdery mildew 2 - do­
- HMW glutenin subunits (Ax, Gx + Gy) 1 - do-
T dicoccoides(AB) - Stripe rust 1 T. durum
I - do- 1 T aestivum
- HMW sub units (Ax, Ax + Ay) 3 T durum
Ae. squarrosa (D) - Leaf rust 1 T. aestivum
- Kamal bunt 1 - do-
Ae. ovata (UM) Leaf rust, stripe rust, powdery mildew, 1 T. aestivum
kamal bunt, cereal cyst nematode
Ae. triuncialis (UC) - do- 1 T aestivum
Ae. caudata (C) - do- 2 T. aestivum
Ae. umbellulata (U) - do- 2 T aestivum
* alien resistance gene for the respective disease mentioned in thiS column.
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