What are the factors explaining pesticide sprayings on grapevines? A comparison of 440 plots belonging to three wine valleys of Chile

C. Bopp, M. Araya-Alman, A. Engler, R. Jara-Rojas, Y. Igor
Spraying pesticides on grape skins is a common practice in vineyards, which has negative impacts on the environment and generates public health challenges. This work aims to identify the factors that explain the intensity of pesticide sprayings measured in conventional vineyards. Data were obtained from face-to-face interviews to 440 vine growers from the O'Higgins and Maule regions in Central-South Chile. The study used vineyard structural information and vine grower's characteristics complemented with high spatial resolution data of soil and weather variables. A principal component analysis (PCA) was performed to explore correlations in the sample and select relevant variables related to the number of pesticide applications in vineyards. Subsequently, two Poisson regression models were estimated to identify the factors associated with a higher or lower level of spraying. The first model used the whole set of variables and the second one used the components extracted from the PCA. The PCA showed significant relationships between high spatial resolution and vineyard scale data. The number of pesticide sprayings is positively correlated to mechanization, grape prices, surface, and educational level, but negatively correlated to summer precipitation and southern valleys. The Poisson regression results indicate that the intensity of pesticide sprayings increases with the size of the vineyard and the degree of mechanization but decreases with cultivar specialization. This means that vineyards having fewer cultivars are exposed to fewer sprayings. In addition, we also found that vine growers located in the Maule valley spray significantly less than in the Rapel valley, which might be explained by different agricultural competitiveness and structural conditions of the study's valleys. To decrease the pesticide use in vine-growing, policy makers might consider these preliminary findings in order to focus on extension programs.
Bopp, C., Araya-Alman, M., Engler, A., Jara-Rojas, R. and Igor, Y. (2021). What are the factors explaining pesticide sprayings on grapevines? A comparison of 440 plots belonging to three wine valleys of Chile. Acta Hortic. 1314, 329-336
DOI: 10.17660/ActaHortic.2021.1314.41
pesticide use, vine growers, high spatial resolution, GIS, PCA, Vitis vinifera

Acta Horticulturae