2024-03-28T08:13:18Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/453282020-05-08T10:43:25Zcom_10261_75com_10261_6col_10261_328
Detecting water stress effects on fruit quality in orchards with time-series PRI airborne imagery
Suárez Barranco, María Dolores
Zarco-Tejada, Pablo J.
González-Dugo, Victoria
Jiménez-Berni, José A.
Sagardoy Calderón, Ruth
Morales Iribas, Fermín
Photochemical Reflectance Index (PRI
EPS
Water stress
Fruit quality
TSS/TA
Multispectral remote sensing
Thermal
13 Pags., 4 Tabls., 12 Figs.
A methodology for the assessment of fruit quality in crops subjected to different irrigation regimes is presented. High spatial resolution multispectral and thermal airborne imagery were used to monitor crown temperature and the Photochemical Reflectance Index (PRI) over three commercial orchards comprising peach, nectarine and orange fruit trees during 2008. Irrigation regimes included sustained and regulated deficit irrigation strategies, leading to high variability of fruit quality at harvest. Stem water potential was used to monitor individual tree water status on each study site. Leaf samples were collected for destructive sampling of xanthophyll pigments to assess the relationship between the xanthophyll epoxidation state (EPS) and PRI at leaf and airborne-canopy level. At harvest, fruit size, Total Soluble Solids (TSS) and Tritatable Acidity (TA) were measured to characterize fruit quality. A statistically significant relationship between EPS and PRI was found at the leaf (r2 = 0.81) and canopy level (r2 = 0.41). Airborne-derived crown PRI calculated from the imagery acquired during the fruit growth was related to the ratio of the total soluble solids normalized by the tritatable acidity (TSS/TA), an indicator of fruit quality measured on the same trees, yielding a coefficient of determination of r2 = 0.50. The relationship between the integral of PRI time-series and TSS/TA yielded a coefficient of determination of r2 = 0.72 (peach) and r2 = 0.61 (nectarines). On the contrary, the relation between TSS/TA and the time-series of crown thermal imagery was very weak (r2 = 0.21 and 0.25 respectively). These results suggest that a physiological remote sensing indicator related to photosynthesis, such as PRI, is more appropriate for fruit quality assessment than crown temperature, the established method of water stress detection, which is more related to crown transpiration. A radiative transfer modelling study was conducted to assess the potential validity of this methodology for fruit quality assessment when using medium spatial resolution imagery. The analysis shows important effects of soil and shadows on the PRI vs EPS relationship used for fruit quality assessment if non-pure crown reflectance was extracted from the imagery.
2012-02-09T11:59:10Z
2012-02-09T11:59:10Z
2010-02
artículo
Suárez L, Zarco-Tejada PJ, Gonazález-Dugo V, Berni JAJ, Sagardoy R, Morales F. Detecting water stress effects on fruit quality in orchards with time-series PRI airborne imagery. Remote Sensing of Environment 114 (2): 286-298 (2010)
0034-4257
http://hdl.handle.net/10261/45328
10.1016/j.rse.2009.09.006
eng
http://dx.doi.org/10.1016/j.rse.2009.09.006
closedAccess
Elsevier