Application of DEXiPM® to assess the sustainability of an innovative apple production system : the exclusion netting

Tree crops production are highly dependent on external inputs, namely pesticides. Redesign tree crop production on other bases becomes a necessity. Before being tested in an experimental station or in real farm conditions, the global sustainability of these newly designed orchards needs to be evaluated. Adapted on the DEXiPM® model, the DEXiPM-pomefruit tool has been designed to make an ex ante assessment of the sustainability of innovative orchard systems. This model is based on a decision tree breaking the decisional problems of sustainability assessment into simpler units, referring to the economic, social and environmental dimensions of sustainability. In the frame of the PURE European project, we tested DEXIPM-pomefruit relevancy to assess the sustainability of innovative orchards. Two apple production systems were compared: one with exclusion netting against codling moth and one without. Exclusion netting is an innovative control method, which decreases the number of treatments by 30 % since all treatments against codling moth are suppressed. Moreover nets represent a good protection against yield loss risk due to climatic conditions (i.e. hail). However, its cost requires an important investment capacity. Assessed by DEXiPM-Pomefruit, the exclusion netting system globally ranked better than the uncovered system. Concerning the social aspect, the result was similar for both production systems. In contrast, economical performances were improved in orchards covered with nets, which are therefore protected against the climatic risk of yield loss. Moreover, the important decrease in pesticide use under nets contributed to improve all environmental impact indicators. DEXiPM-pomefruit helped selecting the most promising innovations in a given context. It was also used as a dashboard to determine strengths and weaknesses of the tested production systems and therefore to identify potential improvements.