Abstract
Common buckwheat (Fagopyrum esculentum Moench) is a robust plant with high resistance to different environmental constraints. It contains high levels of calcium oxalate (CaOx) druse crystals, although their role remains obscure. The objective was to examine the effects of water shortage on plant biomass partition and leaf traits and formation of CaOx druse crystals in common buckwheat. Buckwheat plants were exposed to favorable and reduced water availability for 28 days. The element composition and morphological, biochemical, physiological and optical traits of the leaves, and the plant biomass were investigated under these conditions. Measurements of photochemical efficiency of photosystem II showed undisturbed functioning for buckwheat exposed to water shortage, apparently due to partially closed stomata and more efficient water regulation. Strong relationships were seen between water-related parameters and Ca, Mn and S content, and size and density of CaOx druse crystals. Redundancy analysis revealed the importance of the size of CaOx druse crystals to explain reflection in the UV range. Water shortage resulted in shorter plants with the same leaf mass (i.e., increased mass:height ratio), which, together with denser leaf tissue and higher content of photosynthetic pigments and protective substances, provides an advantage under extreme weather conditions.
Highlights
Changes in the global climate are resulting in more pronounced droughts, which have a deleterious effect on global crop production and might compromise food security in the world [1]
Two significantly different soil moisture levels were created for the experimental period that was maintained for 28 days
If we considered leaf reflectance spectra according to the individual spectral regions, redundancy analysis revealed that the size of calcium oxalate (CaOx) druse crystals explained 46.2% (p = 0.004) of the variability of the reflectance in the UV region
Summary
Changes in the global climate are resulting in more pronounced droughts, which have a deleterious effect on global crop production and might compromise food security in the world [1]. Reported that due to drought events, crop yields are likely to show reductions of >50% by 2050, and potentially by almost 90% by 2100. Adaptive responses to drought stress are generally seen as alterations in plant phenotype and morphology due to changes in gene expression [4]. During their evolution, plants have acquired a variety of morphological and physiological traits that allow them to resist drought stress and physical damage to the plant [5], as in addition to drought, plants need to resist extreme events such as heavy precipitation and strong winds [6]. The first response of any Plants 2020, 9, 917; doi:10.3390/plants9070917 www.mdpi.com/journal/plants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
