Plant Soil

Electronic Supplementary Material

Automatic drought stress detection in grapevines without using conventional threshold values

Annelies BaertA, D ∙ Kris VillezB, C ∙ Kathy SteppeA

A Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium ∙ B Laboratory for Intelligent Process Systems, School of Chemical Engineering, Purdue University, West Lafayette, IN-47907, USA ∙ C Process Engineering, Eawag, Dübendorf, CH-8600, Switzerland ∙ D Corresponding author: Annelies Baert – email:

Microclimatic conditions during the experiment in 2010

Fig. S1 Microclimatic conditions: (a) photosynthetic active radiation (PAR), (b) air temperature (Tair) and (c) vapour pressure deficit (VPD) during the experiment in 2010, i.e. repetition 1. Time is given in day of year (DOY)

Microclimatic conditions during the experiments in 2012

Fig. S2 Microclimatic conditions: (a) photosynthetic active radiation (PAR), (b) air temperature (Tair) and (c) vapour pressure deficit (VPD) during the experiments in 2012, i.e. control 1, 2 and repetitions 2 to 5. Time is given in day of year (DOY)

Analysis of Repetition 1 (2010)

Fig. S3 Repetition 1: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a drought-stressed grapevine. Time is given in day of year (DOY). The grey area marks the period of drought stress for the plant (DOY 199 – 210), the dark grey area the day of resumed irrigation, until the irrigation event

Analysis of control 1 (2012)

Fig. S4 Control 1: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a control grapevine. Time is given in day of year (DOY)

Fig. S5 Control 1: square root of Q statistic as a function of time (in day of year, DOY) of Unfold Principal Component Analysis (UPCA) based on (a) sap flow rate (SF) and (b) stem diameter variations (D) for a control grapevine. The dotted lines indicate the statistical 99% limits Qα

Analysis of control 2 (2012)

Fig. S6 Control 2: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a control grapevine. Time is given in day of year (DOY)

Fig. S7 Control 2: square root of Q statistic as a function of time (in day of year, DOY) of Unfold Principal Component Analysis (UPCA) based on (a) sap flow rate (SF) and (b) stem diameter variations (D) for a control grapevine. The dotted lines indicate the statistical 99% limits Qα

Analysis of repetition 2 (2012)

Fig. S8 Repetition 2: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a drought-stressed grapevine. Time is given in day of year (DOY). The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation, until the irrigation event

Fig. S9 Influence of a different calibration period for the Unfold Principal Component Analysis (UPCA) model based on sap flow rate, SF, of a drought-stressed grapevine (repetition 2): square root of Q statistic as a function of time for the model calibrated with (a) DOY 116 – 162 or (b) DOY 142 – 162. The dotted lines indicate the statistical 99% limits Qα. The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation (until the irrigation event). Clear visible symptoms of drought stress appeared on DOY 177

Fig. S10 Influence of a different calibration period for the Unfold Principal Component Analysis (UPCA) model based on stem diameter variations, D, of a drought-stressed grapevine (repetition 2): square root of Q statistic as a function of time for the model calibrated with (a) DOY 116 – 162 or (b) DOY 142 – 162. The dotted lines indicate the statistical 99% limits Qα. The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation (until the irrigation event). Clear visible symptoms of drought stress appeared on DOY 177

Analysis of repetition 3 (2012)

Fig. S11 Repetition 3: (a) stem diameter variations (D) and (b) stem water potential (Stem WP) of a drought-stressed grapevine. Time is given in day of year (DOY). The grey area marks the period of drought stress for the plant (DOY 142-156), the dark grey area the day of resumed irrigation, until the irrigation event

Fig. S12 Repetition 3: square root of Q statistic as a function of time (in day of year, DOY) of (a) Unfold Principal Component Analysis (UPCA) and (b) Functional Unfold Principal Component Analysis (FUPCA) based on stem diameter variations (D) for a drought-stressed grapevine. The grey area marks the period of drought stress for the plant (DOY 142 – 156), the dark grey area the day of resumed irrigation and the dotted lines indicate the statistical 99% limits Qα

Analysis of repetition 4 (2012)

Fig. S13 Repetition 4: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a drought-stressed grapevine. Time is given in day of year (DOY). The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation, until the irrigation event

Fig. S14 Repetition 4: square root of Q statistic as a function of time (in day of year, DOY) of Unfold Principal Component Analysis (UPCA) based on (a) sap flow rate (SF) and (b) stem diameter variations (D) for a control grapevine. The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation and the dotted lines indicate the statistical 99% limits Qα

Analysis of repetition 5 (2012)

Fig. S15 Repetition 5: (a) Sap flow rate (SF), (b) stem diameter variations (D) and (c) stem water potential (Stem WP) and soil water potential (Soil WP) of a drought-stressed grapevine. Time is given in day of year (DOY). The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation, until the irrigation event

Fig. S16 Repetition 5: square root of Q statistic as a function of time (in day of year, DOY) of Unfold Principal Component Analysis (UPCA) based on (a) sap flow rate (SF) and (b) stem diameter variations (D) for a control grapevine. The grey area marks the period of drought stress for the plant (DOY 163 – 180), the dark grey area the day of resumed irrigation and the dotted lines indicate the statistical 99% limits Qα

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