Seed predation of Aniba rosaeodora Ducke by image analysis

Abstract

Aniba rosaeodora Ducke is a species of high relevance in the perfumery industry. The overexploitation, irregular fruiting, and high rates of fruit predation, mainly by insects, place Aniba rosaeodora in the list of species threatened with extinction. The objective of this study was to evaluate the efficiency of the analysis of radiographic images in the seeds predated by Heilipus odoratus and the influence of the damages in the germination and the seedling formation process. The cotyledon seeds were submitted to an X-ray test at an intensity of 35 kV for 10 seconds and the predation was analyzed using radiographic images with the Imagej2® software, establishing the categories: small damages (≤ 25%); moderate damages (> 25%-≤ 50%) and severe damages (> 50%). The X-ray test allowed to detect that seeds with holes were not necessarily being preyed on the inside. Despite the losses in the cotyledon reserve due to predation, the seeds are still able to emit roots if the embryonic axis is not compromised. However, the possibilities of emitting the aerial part are drastically reduced as the damage increases. It was concluded that the X-ray test was efficient to confirm the predation without affecting the germination process and that the image analysis is an adequate tool to measure the damage caused by Heilipus odoratus.