Sjemenarstvo, Vol. 25 No. 1, 2008.
Review article
DROUGHT TOLERANCE MECHANISMS IN PLANTS AND THEIR GENETIC BASE IN WHEAT
Snježana Kereša
orcid.org/0000-0003-4034-568X
; Faculty of Agriculture University of Zagreb
Marijana Barić
; Faculty of Agriculture University of Zagreb
Martina Horvat
; Faculty of Agriculture University of Zagreb
Ivanka Habuš Jerčić
; Faculty of Agriculture University of Zagreb
Abstract
Drought tolerance is a complex trait of some plant species and genotypes determined by different morphological and/or physiological traits. Tolerant genotypes can circumvent drought in different ways: (1) by early maturity (mechanism of drought escape), (2) by closing stomata that prevents excessive transpiration, but also reduces photosynthesis (mechanism of drought avoidance), or (3) by enhanced accumulation of different osmolites that maintain plant turgor and enable normal metabolism in water stress conditions (mechanism of drought tolerance). The very important is also the ability of tolerant plants to defend against oxidative stress as part of water stress. Most of the genes responsible for tolerance to drought have inducible promotors, and abscisic acid (ABA) is a signal that induces many of them. Many loci for quantitative traits (QTL-s) that control drought tolerance in wheat have been identified and mapped on different chromosomes. Apart from conventional selection for drought tolerance, great efforts have been made to produce genetically modified plants tolerant to drought. Genetically modified wheat showed high drought tolerance in field conditions.
Keywords
drought; mechanisms of drought tolerance; wheat; genetic modifications
Hrčak ID:
26062
URI
Publication date:
14.7.2008.
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