Water use efficiency of sugar beet genotypes: A relationship between growth rates and water consumption

Abstract

Climatic changes are expected to lead to an increase in frequency and intensity of drought in the future and thus to periods of water shortage (IPCC, 2013). In Central Europe, the recent succession of summer drought periods (2015)(2016)(2017)(2018) is in its extent unprecedented compared with the last 2100 years (Büntgen et al., 2021). However, water is a fundamental prerequisite for the development and growth of plants. Likewise, sugar beet yield formation is strongly dependent on water uptake (Jaggard et al., 2007(Jaggard et al., , 2010. There is evidence that the demand for resources such as water is determined by the growth rate (White et al., 2016).The growth rate changes during growth and is highest for sugar beet earlier in the season (Hoffmann et al., 2020). For sugar beet, the relationship between water consumption and growth rate, as well as the development of growth rate during different periods of drought stress, has not yet been comprehensively studied.Sugar beet growth rate has often been determined by the yield increment between two sequential harvest dates (Bloch & Hoffmann, 2005;Kenter et al., 2006). However, this is a destructive approach, and furthermore, it cannot reflect the exact changes at any time point in longer harvest intervals, especially when growth is disturbed by stress. A non-destructive method could be a solution to study growth and impact of abiotic stress throughout the entire growing season.One option for non-destructive analysis of growth could be the phenotyping with sensor technologies as described for cereals

Water use efficiency responses to fluctuating soil water availability in contrasting commercial sugar beet varieties

“…Both sugar beet varieties responded similarly to the first and second drought, suggesting the crop did not acclimate to avoid or better cope with water deficit. This has also been observed in glasshouse studies where sugar beet was exposed to three temporary water deficits but no acclimation was evident in photosynthetic or biochemical responses ( Leufen et al., 2016 ; Ebmeyer and Hoffmann, 2022 ). This recovery is mediated by a range of physiological and biochemical mechanisms.…”

“…Both sugar beet varieties responded similarly to the first and second drought, suggesting the crop did not acclimate to avoid or better cope with water deficit. This has also been observed in glasshouse studies where sugar beet was exposed to three temporary water deficits but no acclimation was evident in photosynthetic or biochemical responses (Leufen et al, 2016;Ebmeyer and Hoffmann, 2022). This recovery is mediated by a The relationship between carbon isotope discrimination (D 13 C) and (A) intrinsic water use efficiency (WUE i ) (P<0.001 R 2 = 0.17), (B) Dry matter water use efficiency (WUE DM ) (P=0.001 R 2 = 0.30) and (C) White sugar yield water use efficiency (WUE WS ) (P=0.004 R 2 = 0.24).…”