Europ. J. Agronomy 59 (2014) 67–77 Contents lists available at ScienceDirect European Journal of Agronomy j ourna l h o mepage: www.elsevier.com/locate/eja Use of soil and vegetation spectroradiometry to investigate crop water use efficiency of a drip irrigated tomato S. Marino a,∗ , M. Aria b , B. Basso d , A.P. Leone c , A. Alvino a a Department of Agricultural, Environmental and Food Sciences (DAEFS), University of Molise, Via De Sanctis, I-86100 Campobasso, Italy b Department of Economics and Statistics, University of Study of Napoli Federico II, via Cintia 26, 80126 Napoli, Italy c Department of Geological Sciences, Michigan State University, 206 Natural Science Building, East Lansing, MI 48824-1115, United States d CNR — Institute for Mediterranean Agriculture and Forest Systems (ISAFoM), via Patacca 85, 80056 Ercolano, Italy a r t i c l e i n f o Article history: Received 17 June 2013 Received in revised form 14 May 2014 Accepted 24 May 2014 Keywords: Tomato yield Water use efficiency Vegetation indices Irrigation management a b s t r a c t An agronomic research was conducted in Tuscany (Central Italy) to evaluate the effects of an advanced irrigation system on the water use efficiency (WUE) of a tomato crop and to investigate the ability of soil and vegetation spectroradiometry to detect and map WUE. Irrigation was applied following an innovative approach based on CropSense system. Soil water content was monitored at four soil depths (10, 20, 30 and 50 cm) by a probe. Rainfall during the crop cycle reached 162 mm and irrigation water applied with a drip system amounted to 207 mm, distributed with 16 irrigation events. Tomato yield varied from 7.10 to 14.4 kg m -2 , with a WUE ranging from 19.1 to 38.9 kg m -3 . The irrigation system allowed a high yield levels and a low depth of water applied, as compared to seasonal ET crop estimated with Hargraves’ formula and with the literature data on irrigated tomato. Measurements were carried out on geo-referenced points to gather information on crop (crop yield, eighteen Vegetation indices, leaf area index) and on soil (spectroradiometric and traditional analysis). Eight VIs, out of nineteen ones analyzed, showed a significant relationship with georeferenced yield data; PVI maps seemed able to return the best response, before harvesting, to improve the knowledge of the area of cultivation and irrigation system. CropSense irrigation system reduced seasonal irrigation volumes. Some vegetation indexes were significantly correlated to tomato yield and well identify, a posteriori, crop area with low WUE; spectroradiometry can be a valuable tool to improve irrigated tomato field management. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Agricultural water use plays the most critical role in water resources management all around the world (Köksal, 2008). The value of water will go up in the century for the severe competition for water from human beings, intensive agriculture, flora and fauna, etc. (Bouwer, 2000). Irrigated agriculture is a major consumer of water and accounts for about two thirds of the total fresh water assigned to human uses (Fereres and Evans, 2006). As a general rule, agriculture show often a low irrigation water use efficiency, for this reason irrigation scientists are forced to develop water sav- ing irrigation strategies (Payero et al., 2009). Sustainable irrigation water management should simultaneously achieve two objectives: sustaining irrigated agriculture for food security and preserving the associated natural environment. A stable relationship should be ∗ Corresponding author. Tel.: +39 0874404709; fax: +39 0874404713. E-mail addresses: stefanomarino@unimol.it, stefanomarino@gmail.com (S. Marino). maintained between these two objectives now and in the future, while potential conflicts between these objectives should be miti- gated through appropriate irrigation practices. The sustainable use of water in agriculture has become a priority and the adoption of irrigation strategies which may allow saving irrigation water and maintaining satisfactory yields, thus improving water use effi- ciency (WUE), may contribute to the preservation of this even more restricted resource (Parry et al., 2005; Topcu et al., 2007). Efficient use of water in any irrigation system is becoming important particularly in arid and semiarid region where water is a scarce commodity; in this area maximizing water productiv- ity may be more profitable to the farmer than maximizing crop yield (Pereira et al., 2002). The economic and environmental bene- fits of improving the volumetric efficiency of irrigation are obvious in both the value of the water saved and the additional produc- tion possible with this water. Hence, there is a triple bonus for improving irrigation precision including: (a) maximizing yield and quality of production, (b) reducing water losses below the root zone, and (c) conserving the resource base, by minimizing the risk of groundwater salinity and thus enhancing sustainability. These http://dx.doi.org/10.1016/j.eja.2014.05.012 1161-0301/© 2014 Elsevier B.V. All rights reserved.