Remote sensing technology for grape health status monitoring under nursery conditions

Remote sensing applications are becoming a valuable tool for crop production, including the viticulture sector. Different studies report the use of unmanned aerial vehicles (UAVs) for providing grapevine vigour indexes related to the canopy shape and showing relationships with plant physiology and productivity. With this study, remote sensing UAV-based technology was applied under grape nursery condition on a mother plant field and on a rootstock production field, to evaluate possible relationships with grapevine trunk diseases. In the mother plants fields, were present the 1103 Paulsen and Kober 5BB varieties, while rootstock field was planted with Kober 5BB, 140 Ruggieri and 1103 Paulsen varieties. The NDVI data collected by DJI Mavic 3M, (DJI Sciences and Technologies Ltd, Shenzhen e Pechino, Cina) and analysed by using JMicrovision software (jmicrovision.github.io), allowed to follow the canopy development, along June-August months. In the mother plant field, the presence of weed plants resulted in the overestimate NDVI value for grape plants and further analysis IA based are setting. In the rootstock production field, a lower NDVI index were observed for Kober 5BB compared to 140 Ruggieri and 1103 Paulsen. NDVI data were positively correlated r≥0.7 with the percentage of un-sprouted grapevine cuttings. These latter show internal wood browning symptoms whose fungal species of the Botryosphaeriaceae family, and belonging to the genera Diaporthe, Pestalotia, Fusarium, and Dematophora were isolated. In conclusion, the use of remote sensing represents a promising methodology for monitoring young vine health under nursery condition.