A Simple Method for Simulating Drought Effects on Plants

Abstract

Drought is expected to increase in frequency and severity in many regions in the future, so it is important to improve our understanding of how drought affects plant functional traits and ecological interactions. Imposing experimental water deficits is key to gaining this understanding, but has been hindered by logistic difficulties in maintaining consistently low water availability for plants. Here, we describe a simple method for applying soil water deficits to potted plants in glasshouse experiments. We modified an existing method (the "Snow and Tingey system") in order to apply a gradual, moderate water deficit to 50 plant species of different life forms (grasses, vines, shrubs, trees). The method requires less maintenance and manual handling compared to other water deficit methods, so it can be used for extended periods of time and is relatively inexpensive to implement. With only a few modifications, it is possible to easily establish and maintain soil water deficits of differing intensity and duration, as well as to incorporate interacting stress factors. We tested this method by measuring physiological responses to an applied water deficit in a subset of 11 tree/shrub species with a wide range of drought tolerances and water-use strategies. For this subgroup of species, stomatal conductance was 2-17 times lower in droughted plants than controls, although only half of the species (5 out of 11) experienced midday leaf water potentials that exceeded their turgor loss (i.e., wilting) point. Leaf temperatures were up to 8°C higher in droughted plants than controls, indicating that droughted plants are at greater risk of thermal damage, relative to unstressed plants. The largest leaf temperature differences (between droughted and well-watered plants) were in species with high rates of water loss. Rapid osmotic adjustment was observed in leaves of five species when drought stress was combined with an experimental heatwave. These results highlight the potential value of further ecological and physiological experiments utilizing this simple water deficit method to study plant responses to drought stress.

Analysis of Dynamic Global Transcriptional Atlas Reveals Common Regulatory Networks of Hormones and Photosynthesis Across Nicotiana Varieties in Response to Long-Term Drought

“…However, most of them have focused on early or long-time responses, or in a single variety with or without time series, or between multiple varieties (often without time series), or on media, or non-industrial crops, which limit the application in field improvement in real farming. Different durations of drought treatment were used in existing reports (Kang et al, 2011;Spieß et al, 2012;Yan et al, 2012;Chung et al, 2016;Ogbaga et al, 2016;Shan et al, 2018;Chen et al, 2019;Zenda et al, 2019;Marchin et al, 2020). We propose that long-term drought stress should be relative long time e.g., many weeks, usually spanning one or more developmental stages, which may cause severe damage to growth and yield during farming.…”

“…Different varieties in the same plant species have different adaptivity to drought stress, which has both genetic and expressional bases. Some existing studies on drought response in different varieties or species are available but most of them are limited to one variety (Su et al, 2013;Chung et al, 2016;Zenda et al, 2019), or between varieties but not on time series (Kang et al, 2011;Ogbaga et al, 2016;Chen et al, 2019;Marchin et al, 2020). Most of the existing studies are focused on early responses (Chung et al, 2016;Zenda et al, 2019).…”

Breeding for Climate Change Resilience: A Case Study of Loblolly Pine (Pinus taeda L.) in North America

“…Projections from ensemble climate models (Figure 4B) suggest that the ability to survive a period of 3-4 weeks without rainfall during the first summer after planting is likely to be a valuable trait to increase the likelihood of successful plantation establishment in much of the southeastern United States by mid-century. Seedlings can be exposed to such stresses under controlled conditions now, either in greenhouse studies with controlled delivery of water (Marchin et al, 2020), or by field planting seedlings in regions with little to no summer rainfall and providing supplemental irrigation during spring growth and then withdrawing irrigation to impose the desired drought stress during the summer. The latter method could also have the additional feature of imposing higher summer temperatures than are currently common in the natural range of loblolly pine, but may become common in the future (Figure 4D).…”

Variability and selection among mutant families of wheat for biomass allocation, yield and yield‐related traits under drought‐stressed and non‐stressed conditions

“…The significant (p < .05) effects of the interactions involving genotype, environment and water regimes on the traits such as days to 90% maturity, shoot biomass, root biomass, total biomass, productive tiller number, spikelet per spike, thousand seed weight and grain yield (Table 1) suggest that genotypic and environmental factors are Marchin et al, 2020;Osakabe et al, 2014;Robbins & Dinneny, 2018;Tátrai et al, 2016). Mwadzingeni et al (2017) would be imperative to assess whether such genotypes would have dynamic stability and performance under improved moisture conditions to minimize potential yield penalties (Hooshmandi, 2019).…”