TY - JOUR AU - Echávez-Badel, Rodrigo AU - Gómez-Galvé, Jorge E. AU - Alameda-Lozada, Myrna PY - 2000/04/01 Y2 - 2024/03/29 TI - Characterization of Rhizoctonia spp. isolates collected from Phaseolus vulgaris in Puerto Rico JF - The Journal of Agriculture of the University of Puerto Rico JA - JAUPR VL - 84 IS - 1-2 SE - Articles DO - 10.46429/jaupr.v84i1-2.3903 UR - https://revistas.upr.edu/index.php/jaupr/article/view/3903 SP - 79-86 AB - Thirteen isolates collected from soil samples, infected seeds, hypocotyls, leaves and pods of common beans (<em>Phaseolus vulgaris</em>) grown in the northwestern, southern and western areas of Puerto Rico were identified as <em>Rhizoctonia solani</em> (Rs), and one as binucleate <em>Rhizoctonia</em> sp. (Rb). All isolates were characterized by the nuclear condition of the hyphae cell and the anastomosis technique. Seven Rs isolates (54%) were classified into anastomosis group AG 4, and six (46%) were assigned to AG 1. The microsclerotic Rb isolate did not anastomose with any of the AG testers. The AG 4 isolates produced only microsclerotia. Five AG 1 isolates (36%) were macrosclerotic, and one was microsclerotia The Rs isolates and the Rb isolate differed in mycelia radial growth after 48 h of incubation at 28° C on acidified potato dextrose agar. The sexual stage of the isolates was not observed throughout this research. Storing dried beet (<em>Beta vulgaris</em> L.) seeds colonized by <em>R. solani</em> for at least a year at 4° C in the dark seems to be a reliable method to ensure viability and virulence of the pathogen. ER -