Agriculture Reference
In-Depth Information
approach. A more successful alternative to devel-
oping synthetic tetraploids has been to directly
cross durum wheat with
T. boeticum
and
T. urartu
for the improvement of stripe rust resistance
(Valkoun 2001).
As much of the variation in synthetic wheat is
not agronomically useful, the challenge for plant
breeders is to identify and introduce useful genes
into their elite materials. Even though Zhang
et al. (2005) found that little of the primary
synthetic parent remained after crossing and
selection, the introduction of synthetic materials
into the CIMMYT wheat breeding program
has signifi cantly increased the latent diversity
among more recently developed advanced lines
(Warburton et al., 2006).
The constraints facing the global wheat
improvement research community are becoming
ever more diffi cult. Exhaustion of genetic vari-
ability for disease resistance, increasing human
population pressures, reduced availability of
water for agriculture, and a changing climate
present signifi cant challenges. Synthetic hexa-
ploid wheat is likely to be an important source of
new genetic variation for the mitigation of these
constraints.
Cakmak, O., S. Eker, A. Ozdemir, N. Watanabe, and H.J.
Braun. 1999. Expression of high zinc effi ciency of
Aegilops
tauschii
and
Triticum monococcum
in synthetic hexaploid
wheats. Plant Soil 215:203-209.
Cakmak, O., and M. Tanksley. 2000. Possible roles of zinc in
protecting plant cells from damage by reactive oxygen
species. New Phytol. 146:185-205.
Calderini, D.F., and I. Ortiz-Monasterio. 2003. Are synthetic
hexaploids a means of increasing grain element concentra-
tions in wheat? Euphytica 134:169-178.
Davies, J., W.A. Berzonsky, and G.D. Leach. 2006. A com-
parison of marker-assisted and phenotypic selection for
high grain protein content in spring wheat. Euphytica
152:117-134.
Dreccer, M.F., M.G. Borgognone, F.C. Ogbonnaya, R.M.
Trethowan, and B. Winter. 2007. CIMMYT-selected
synthetic bread wheats for rainfed environments: Yield
evaluation in Mexico and Australia. Field Crops Res.
100:218-228.
Dreccer, M.F., F.C. Ogbonnaya, and M.G. Borgognone.
2004. Sodium exclusion in primary synthetic wheats. p.
118-121.
In
C.K. Black, J.F. Panozzo, and G.J. Rebetzke
(ed.) Proc. Aust. Cereal Chem. Conf., 54th & Wheat
Breeders Assembly, 11th, Canberra. 21-24 Sept. 2004.
Canberra Cereal Chemistry Division, RACI.
Dreccer, M.F., F. Ogbonnaya, G. Borgognone, and J.
Wilson. 2003. Boron tolerance is present in primary
synthetic wheats. p. 1130-1132.
In
N.E. Pogna, M.
Romano, E.A. Pogna, and G. Galterio (ed.) Proc. Int.
Wheat Genet. Symp., 10th, Paestum, Italy. 1-6 Sept.
2003. Istituto Sperimentale per la Cerealcoltura, Paestum,
Italy.
Eastwood, R.F., E.S. Lagudah, R. Appels, M. Hannah, and
J.F. Kollmorgen. 1991.
Triticum tauschii
: A novel source of
resistance to cereal cyst nematode (
Heterodera avenae
).
Aust. J. Agric. Res. 42:69-77.
Ehdaie, B., and J.G. Waines. 1992. Heat resistance in
wild
Triticum
and
Aegilops
. J. Genet. Breed. 46:221-
227.
Elias, E.M., and F.A. Manthey. 2005. End products: Present
and future uses. p. 63-86.
In
C. Royo, M. Nachit, N. Di
Fonzo, J.L. Araus, W.H. Pfeiffer, and G.A. Slafer (ed.)
Durum wheat breeding. Haworth Press, Binghamton,
NY.
Feldman, M. 2001. Origin of cultivated wheat. p. 3-53.
In
A.P. Bonjean and W.J. Angus (ed.) The world wheat topic:
A history of wheat breeding. Lavoisier Publishing, Paris,
France.
Gale, M.D. 1989. The genetics of preharvest sprouting in
cereals, particularly in wheat. p. 85-110.
In
N.F. Derera
(ed.) Preharvest fi eld sprouting in cereals. CRC Press,
Boca Raton, FL.
Gandilyan, P.A., Zh.O. Shakaryan, and E.A. Petrosyan.
1986. Synthesis of new emmers and tetraploid speltoids,
and problems of phylogeny in the wheat genus. Biolog. Zh.
Armenii 39:5-15.
Gatford, K.T., P. Hearnden, F. Ogbonnaya, R.F. Eastwood,
and G.M. Halloran. 2002. Novel resistance to pre-harvest
sprouting in Australian wheat from the wild relative
Triti-
cum tauschii
. Euphytica 126:67-76.
REFERENCES
Aguilar-Rincón, V.H., P.R. Singh, and J. Huerta-Espino.
2000. Inheritance of resistance to leaf rust in four synthetic
hexaploid wheats. Agrociencia 34:235-246.
Appels, R., and E.S. Lagudah. 1990. Manipulation of chro-
mosomal segments from wild wheat for the improvement
of bread wheat. Aust. J. Plant Physiol. 17:253-366.
Assefa, S., and H. Fehrmann. 2004. Evaluation of
Aegilops
tauschii
Coss. for resistance to wheat stem rust and inheri-
tance of resistance genes in hexaploid wheat. Genet.
Resour. Crop Evol. 51:663-669.
Azizinya, S., M.R. Ghanadha, A.A. Zali, B.Y. Samadi, and
A. Ahmadi. 2005. An evaluation of quantitative traits
related to drought resistance in synthetic wheat genotypes
in stress and non-stress conditions. Iran. J. Agric. Sci.
36:281-293.
Berzonsky, W.A., K.D. Hartel, S.F. Kianian, and G.D.
Leach. 2004. Registration of four synthetic hexaploid
wheat germplasm lines with resistance to Fusarium head
blight. Crop Sci. 44:1500-1501.
Boru, G., M. van Ginkel, W.E. Kronstad, and L. Boersma.
2001. Expression and inheritance of tolerance to waterlog-
ging stress in wheat. Euphytica 117:91-98.
