Leufen, G., Noga, G. & Hunsche, M. Acta Physiol Plant (2013) 35: 1763. doi:10.1007/s11738-012-1213-6
Greenhouse and field experiments were carried out to evaluate the potential of specific fluorescence emission parameters for the detection of a temporary water deficit in selected sugar beet (Betavulgaris L.) genotypes. Changes in the plant physiology due to reduced water availability were recorded with a multiparameter fluorescence sensor in addition to destructive and non-invasive reference analysis. Our results show that an insufficient water supply is followed by only slight changes of the UV-excited blue fluorescence. However, significant alterations due to desiccation were detected in several chlorophyll fluorescence parameters measured after excitation with UV, green and red light. In the scope of our activities, the relevance of the green light source for the fluorescence excitation became evident and enabled to characterize cultivar-specific reactions during dehydration and re-watering period. A field experiment was conducted to validate the data collected in the greenhouse. As proven, several days of low water supply led to effects similar to those observed in the greenhouse study. Our results indicate that the far-red fluorescence, as well as the simple and complex fluorescence ratios having the chlorophyll fluorescence as basis, is the appropriate parameter to evaluate physiological responses of sugar beet plants exposed to a short-term, temporary water deficit.
Blue fluorescenceChlorophyll a fluorescenceDrought stressStress physiologyGreenhouse studyField experiment
Supplementary Fig. 1. Influence of water supply on the far-red fluorescence (FRF) recorded after green excitation light (G) on the sugar beet cultivars Pauletta (a), Berenika (b), Cesira (c) and Mauricia (d) cultivated in greenhouse. Measurements were regularly taken on marked leaves between 59 and 105 DAS. Grey regions in the graphs illustrate the periods where the water supply was stopped in the case of the non-irrigated plants. Values indicate mean ± SE (n ≥ 8). Asterisks indicate significant differences with a P ≤ 0.05 (t test) between leaves of irrigated (control) and seasonal non-irrigated (stressed) plants for each cultivar and measuring day (DOCX 2064 kb)
Supplementary Fig. 2. Influence of a seasonal water shortage on the blue fluorescence (BF) excited with UV-light on the four sugar beet genotypes Pauletta (a), Berenika (b), Cesira (c) and Mauricia (d). Leaves were measured at day 104 and 108 after sowing of plants cultivated under field conditions. Columns indicate mean ± SE (n = 96). Asterisks mean significant values with a P ≤ 0.05 (t test) between leaves of irrigated (control) and rainfed (stressed) plants for each cultivar and measuring day (DOCX 38 kb)