Drought and high temperature increases preharvest sprouting tolerance in a genotype without grain dormancy

• Published in: Euphytica Vol. 143; no. 3; pp. 277 - 283
• Main Authors: Biddulph, T.B, Mares, D.J, Plummer, J.A, Setter, T.L
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.09.2005
• Subjects: abscisic acid; air temperature; Drought; Embryos; Environmental conditions; genotype; Genotype & phenotype; genotype-environment interaction; Grain; grain sprouting; hard white spring wheat; High temperature; Low temperature; pre-harvest sprouting; Rain; seed dormancy; seed germination; Seeds; Spring wheat; stress tolerance; Triticum aestivum
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-005-7882-0

Issue Title: Special Issue: Proceedings of the 10th International Symposium on Pre-Harvest Sprouting in Cereals, 2004 Preharvest sprouting is common in cereals, which lack grain dormancy when maturing grain is exposed to rainfall or high moisture conditions. Environmental conditions such as drought and high temperature during grain filling have a large effect on the expression of sprouting tolerance. A dormant (DM 2001) and non-dormant (Cunderdin) hard white spring wheat were exposed to drought or irrigated conditions and either low or high temperature during grain filling. Dormancy and embryo sensitivity to ABA were analysed throughout grain filling. The conclusions from this investigation were as follows; firstly DM 2001 was more dormant than Cunderdin, with a four-fold lower germination index (GI) at maturity. Secondly during grain ripening drought increased dormancy and overrides any increase in dormancy with low temperature. Finally embryo sensitivity can be induced in a non-dormant genotype to the extent where the non-dormant genotype in a hot dry environment can have the same phenotype as a dormant genotype grown in a cool wet environment. In summary drought during grain filling increases dormancy suggesting breeders need to avoid drought when screening for sprouting tolerance in order to maximise the chances of identifying genetic differences in grain dormancy and avoid any maturity by drought interactions.[PUBLICATION ABSTRACT]