Effects of drought on leaf carbon source and growth of European beech are modulated by soil type

Abstract

Drought potentially affects carbon balance and growth of trees, but little is known to what extent soil plays a role in the trade-off between carbon gain and growth investment. In the present study, we analyzed leaf non-structural carbohydrates (NSC) as an indicator of the balance of photosynthetic carbon gain and carbon use, as well as growth of European beech (Fagus sylvatica L.) saplings, which were grown on two different soil types (calcareous and acidic) in model ecosystems and subjected to a severe summer drought. Our results showed that drought led in general to increased total NSC concentrations and to decreased growth rate, and drought reduced shoot and stem growth of plants in acidic soil rather than in calcareous soil. This result indicated that soil type modulated the carbon trade-off between net leaf carbon gain and carbon investment to growth. In drought-stressed trees, leaf starch concentration and growth correlated negatively whereas soluble sugar:starch ratio and growth correlated positively, which may contribute to a better understanding of growth regulation under drought conditions. Our results emphasize the role of soil in determining the trade-off between the balance of carbon gain and carbon use on the leaf level and growth under stress (e.g. drought).

Evolution of the Crop Rhizosphere: Impact of Domestication on Root Exudates in Tetraploid Wheat (Triticum turgidum L.)

“…A preliminary observation that arises from the present study is that the soil type might dramatically affect both the plants (particularly in terms of root growth) and the composition of the root exudate in the rhizosphere. Indeed, root growth was highly stimulated here in the Sand100 substrate, which was similar to the effects of low nitrogen conditions on durum wheat (Gioia et al, 2015 ) and of drought in higher plants (Liu et al, 2017 ). This suggests that root growth in tetraploid wheat is under the control of a complex system that can promote growth under suboptimal conditions (e.g., of fertility, water).…”

“…This suggests that root growth in tetraploid wheat is under the control of a complex system that can promote growth under suboptimal conditions (e.g., of fertility, water). This behavior is often associated with sandy soils, with the main function being to increase the root:shoot ratio, and consequently the aptitude to absorb more water and nutrients from the deeper soil layers (Kuster et al, 2013 ; Taeger et al, 2015 ; Liu et al, 2017 ). Interestingly, these trends were much more pronounced here in the wild and domesticated emmer, compared to the modern durum wheat.…”

Effects of Experimental Nitrogen Addition on Nutrients and Nonstructural Carbohydrates of Dominant Understory Plants in a Chinese Fir Plantation

“…The pellets were extracted two more times with 1 M H 2 SO 4 . SS and ST determinations were performed based on absorbance at 625 nm using the same anthrone reagent in a spectrophotometer [28,29]. NSC concentration was obtained by the sum of the total SS and ST.…”

Foliar Pre-Treatment with Abscisic Acid Enhances Olive Tree Drought Adaptability

“…Although 8 days after the beginning of the 3rd recovery period D + ABA plants had not yet displayed a full recovery of A n ( Figure 2B), they maintained higher concentration of TSS, probably at the expense of starch reserves, which decreased with rewatering (Table 1). This response might accomplish the demand for a rapid recovery of physiological functions and growth [54] and suggests that ABA pre-treatment allowed to divert a higher proportion of the newly assimilated carbon into soluble sugar export for plant growth, and less to temporary storage, as starch [55]. Thus, these results with the addition of ABA support the assumption that growth of trees under drought and rewatering cycles are positively associated with higher soluble sugars/starch ratio, and not to higher nonstructural carbohydrates concentration.…”