Dispersal gradient of M. fructicola conidia from peach orchard to an open field

Abstract

Dispersal gradient and the maximum distance that spores of M. fructicola can spread allow the quantification of the relative risk of disease spread from spores originating from local or distant sources. This study aims to estimate the M. fructicola conidia dispersal gradient from the edge of a peach orchard. For that, three sets of spore traps were placed at an open field from the edge of an experimental peach orchard to monitor the conidial dispersal during two successive seasons. The conidia numbers were counted in the first crop season at the following distances: 0 (orchard edge), 92, 104, 118 and 130 m. In the second season, two sets of spore traps were used, with the first set placed at 0 (orchard edge), 16, 32, 64 and 128 m and the second set placed at 0 (orchard edge), 16, 48 and 96 m away from the orchard edge. The first and second crop season assessments of spores were performed for 48 days and 212 days, respectively. GLM exponential model showed a good fit to the M. fructicola dispersal gradient. The interaction between time and distance from the inoculum source (orchard edge) was considered to model the inoculum dispersal. Minimum estimated distances for 1 spore to be detected were 276 and 235 m for the first and the second season, respectively.