Establishment of three strategies in degraded areas within organic vineyards and relevance on soil behaviour, vine physiology and yield components

Summary

The main objective of this study was to determine the impact of three organic strategies (organic compost, green manure and dry mulching) on soil’s physical behaviour, vine physiology and grapevine quality, from 2015 to 2017, within two vineyards: FF and SD. The degraded areas chosen had significant higher disruption of the soil, lower yield, but also lower quality of the grape. The two-years application of compost improved significantly the soil structure, the nitrogen and hydric status of the vine. The dry mulching and the green manure didn’t have significant impact. The vintage effect must be taken in account as the climatic conditions from 2015 to 2017 were heterogeneous and the vintage 2017 particularly dry. However, the treatment impact is proved by the differences observed between the three strategies in 2017, in comparison to 2015. A hydric model (Vineyard Soil Irrigation Model) was performed for the vintage 2017 within FF, to compare the soil water content between the compost strategy and the degraded area. In that extend, the leaf area index was measured at field and the evapotranspiration was calculated using the model of R. L. Snyder. The VSIM model does not put forwards differences of hydric status between the degraded area and the compost strategy, unlike the field measurements of stem water potential which assessed a higher hydric constraint for the degraded area. Hence, the parameters used to run the model should be improved to distinguish between the different strategies