Drought is now considered the most harmful weather phenomena for the global economy. In view of this, increasing the drought resistance of plants is important not only for agriculture as an industry, but also for society as a whole. The use of classical and new breeding and genetic approaches (including editing plant genomes), as well as biotechnological tools associated with the use of physiologically active substances (resistance inducers), requires improving methodological approaches in the study of drought resistance of plants. The review provides a critical analysis of the main methods for creating experimental drought and choosing integral plant indice that characterize their drought resistance. Experimental approaches to studying the main strategies for survival and functioning of cultivated plants under conditions of moisture deficiency are discussed: the isohydric strategy, which is based on water conservation, and the anisohydric strategy, which is based on resistance to dehydration. In the context of these two strategies, the issues of studying the functioning of the main stress-protective systems in plants are considered: osmoregulatory and antioxidant. Emphasis is placed on the specific features of drought tolerance of cultivated cereals, in particular, Triticum aestivum. Approaches to studying the relationships between integral indice of drought tolerance and changes in markers of oxidative stress, antioxidant activity, and increased accumulation of multifunctional low-molecular protective compounds are discussed. The feasibility of using mathematical methods, in particular, meta-analysis for objective generalization of experimental data in the field of plant drought tolerance is noted.
Keywords: drought resistance of plants, experimental approaches, adaptive strategies of plants, osmotic regulation, oxidative stress, antioxidant system
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