Characterization of AG-13, a Newly Reported Anastomosis Group of Rhizoctonia solani

Abstract

Rhizoctonia solani anastomosis group (AG)-13 was collected from diseased roots of field grown cotton plants in Georgia in the United States. Isolates of AG-13 did not anastomose with tester isolates of AG-1 through AG-12. Mycelium of all isolates of AG-13 were light brown but darkened as cultures aged. All isolates produced aerial mycelium. Concentric rings were visible after 3 to 4 days of growth but disappeared as cultures aged and darkened. Individual sclerotia were up to 1.5 mm in diameter, similar in color to the mycelium, and generally embedded in the agar. Clumps of sclerotia up to 5 mm in diameter were produced on the agar surface. All attempts to induce basidiospore production were unsuccessful. The 5.8S region of the rDNA from isolates of AG-13 was identical in length and sequence to isolates of all other AGs of R. solani. Length and sequence of the internal transcribed spacer (ITS) regions of rDNA from isolates of AG-13 were unique among AGs of R. solani. Similarity between AG-13 and other AGs of R. solani ranged from 68 to 85% for ITS region 1 and 85 to 95% for ITS region 2. Selected isolates of AG-13 caused minor or no damage to barley, cauliflower, cotton, lettuce, potato, and radish in laboratory or greenhouse studies.

Caracterização de isolados de Rhizoctonia spp. e identificação de novos grupos de anastomose em jardim clonal de eucalipto

“…Com base no número de núcleos das células vegetativas, as espécies de Rhizoctonia podem ser divididas em três grupos: uni, bi e multinucleadas (Carling et al, 2002). Isolados de R. solani são identificados, segundo a fusão de hifas com isoladosteste, em grupos de anastomose (AG1 a AG13 e AG-BI) (Sneh et al, 1991;Ogoshi, 1996;Carling et al, 2002).…”

“…Isolados de R. solani são identificados, segundo a fusão de hifas com isoladosteste, em grupos de anastomose (AG1 a AG13 e AG-BI) (Sneh et al, 1991;Ogoshi, 1996;Carling et al, 2002). Tais grupos podem ser associados a diferentes características culturais, tipo de hospedeiros, dentre outras.…”

A Comprehensive Overview on Black Scurf of Potato

“…Rhizoctonia solani is a complex species, at least 13 related but distinct genetically anastomosis groups (AGs) (Carling et al, 2002a). AGs have been further divided into subgroups, and subgroups into subsets, on the basis of culture morphology, pathogenicity, host range, nutritional requirements and/or biochemical and genetic properties (Stevens Johnk et al, 1993;Kuninaga et al, 1997Kuninaga et al, , 2000bNicoletti et al, 1999;Carling et al, 2002b).…”

“…At present, 13 AGs (designated AG-1 through AG-13) and 21 subgroups (designated AGs 1-IA, 1-IB, 1-IC, 1-ID, 2-1, 2-2-IIIB, 2-2-IV, 2-2-LD, 2-3, 2-4, 2-BI, 3-IIA, 3-IIB, 3-IIC, 3-TB, 4-HG-I, 4-HG-II, 6-GV, 6-HG-I, 9-TX, 9-TP) are recognised (Ogoshi, 1987;Naito and Kanematsu, 1994;Carling, 1996;Hyakumachi et al, 1998;Carling et al, 1999Carling et al, , 2002aKuninaga et al, 2000a;Priyatmojo et al, 2001). Subgroups within AGs are partially based on differences in one or more biochemical, genetic, or pathogenic characteristic (Ogoshi, 1987).…”

Anastomosis grouping of Rhizoctonia solani and binucleate Rhizoctonia spp. isolated from pepper in Erzincan, Turkey

“…Currently, the multinucleate species R. solani Kühn (teleomorph: Thanatephorus cucumeris (Frank) Donk.) are divided into 14 anastomosis groups: AG-1 to AG-10, AG-BI (Sneh et al 1991), AG-11 (Carling et al 1994), AG-12 (Carling et al 1999), and AG-13 (Carling et al 2002), while binucleate Rhizoctonia spp. (teleomorph: ceratobasidium Rogers) isolates are grouped into AG-A to AG-S (Sneh et al 1991;Sharon et al 2008).…”