Drought Adaptation Mechanisms Should Guide Experimental Design

Abstract

The mechanism, or hypothesis, of how a plant might be adapted to drought should strongly influence experimental designs. For instance, an experiment testing for water conservation should be distinct from a damage tolerance evaluation. Here we define four new, general mechanisms for plant adaptation to drought, so that experiments can be more easily designed based upon the definitions. A series of experimental methods are suggested along with appropriate physiological measurements related to the drought adaptation mechanisms. The suggestion is made that the experimental manipulation should match the rate, length, and severity of soil water deficit needed to test the hypothesized type of drought adaptation mechanism.

Divergent strategies displayed by potato (Solanum tuberosum L.) cultivars to cope with soil drought

“…An ability to maintain yield under soil drought can be achieved by improvement of dehydration avoidance, a component of drought resistance. Dehydration avoidance is often based on different strategies, including xeromorphic features of leaves, early stomata closure and leaf rolling (Benešová et al., ; Gilbert & Medina, ). This type of drought resistance was better developed in the Tajfun/Owacja cultivar pair than in the Gwiazda/Oberon cultivar pair.…”

Comparative drought resistance of temperate grassland species: testing performance trade-offs and the relation to distribution

“…The goal of the experiment was to expose all species to uniformly severe drought conditions to assess whole-plant drought responses in a way that is directly comparable across all species and independent of species interactions. We defined drought as a decrease of water input that leads to a decline of soil moisture, a definition that is commonly used in plant sciences (Gilbert and Medina 2016). Whether the decline of soil moisture affects a plant is determined by its characteristics and can vary between species.…”

<strong>Strengthening the Practical Application of Experiments Assessing Maize Drought Tolerance</strong>

“…therefore, a single indicator cannot fully capture the extent of a given variety's drought response, leading to potentially inaccurate tolerance assessments (Gilbert and Medina, 2016;Chen et al, 2015). Recently, comparisons of inbred lines with hybrids (e.g., Xiang et al, 2017) are also suboptimal for practical breeding purposes given the vast difference in drought regulation mechanisms (Cairns et al, 2012).…”

“…Drought-tolerant plants are typically found through a comparison of variance in relevant indices. Despite the existence of numerous highly targeted proposals for guiding experiment design, current drought evaluation systems for maize remain ambiguous (Gilbert and Medina, 2016). Currently, drought-tolerant maize materials are rarely used for actual breeding because corn production primarily focuses on heterosis to generate desired varieties.…”