ISSN: 2474-8846
Authors: González JAB*, Arcila I, Amaya CZ, Zeist AR and Jaimes EPG
Potato powdery scab is a disease that negatively affects both roots, causing gall formation, and tubers, resulting in brown pustules. Additionally, it leads to the development of resistance structures that can persist in the soil for several years. Globally, it is one of the most limiting diseases for potato cultivation. This study aimed to identify the species present in areas with a historical occurrence of powdery scab and to evaluate their role as alternative hosts for the pathogen. Samples were collected in the municipalities of Santa Rosa de Osos and La Unión (Ant- Col). The presence of structures (plasmodia and cystosori) associated with the pathogen in the roots was determined using trypan blue staining followed by optical microscopy analysis. Morphological identification revealed twenty-six families with pathogen structures, including Acmella mutisii, Amaranthus dubius, Bidens pilosa, Galinsoga quadriradiata, Holcus lanatus, Hypochaeris radicata, Juncus microcephalus, Oxalis corniculata, Pennisetum clandestinum, Phytolacca bogotensis, Poa annua, Polygonum nepalense, Raphanus raphanistrum, Rumex crispus, Sonchus oleraceus, Trifolium repens, Verbena litoralis, along with Fragaria x ananassa, Solanum tuberosum, and Zea mays. Molecular analysis using RT-PCR for the detection of Plasmodiophoromycetes revealed the presence of Spongospora subterranea in Solanum tuberosum; Polymyxa betae in S. tuberosum, O. corniculata, and T. repens; and Polymyxa graminis in Z. mays. This comprehensive study highlights the importance of crop rotation and weed control to disrupt the pathogen’s lifecycle as effective strategies to mitigate the impact of the disease. It emphasizes the role of alternative hosts and their substantial contribution to elevated inoculum levels.
Keywords: Alternate-Hosts; Crop Rotation; Plasmodiophoromycetes; Potato; Sporeballs; Solanum Tuberosum
