Hyphal Anastomosis Reactions, rDNA-Internal Transcribed Spacer Sequences, and Virulence Levels Among Subsets of Rhizoctonia solani Anastomosis Group-2 (AG-2) and AG-BI

Hyphal anastomosis reactions, rDNA-internal transcribed spacer (ITS) sequences, and virulence of isolates representing Rhizoctonia solani AG-BI and six subsets of anastomosis group (AG)-2 (-2-1, -2-2 IIIB, -2-2 IV, -2-2 LP, -2-3, and -2-4) were compared. AG-2-4 is a subset described for the first time in this report. Anastomosis reactions within AG-BI and the listed subsets of AG-2 were generally strong but, between subsets, ranged from strong to a very weak “bridging” -type reaction. Anastomosis reaction alone generally did not provide adequate evidence for placement of an isolate into a subset of AG-2. Anastomosis reactions between AG-BI and the original subsets of AG-2 (-2-1 and -2-2) are very strong; for this reason, we propose that it be included as a subset of AG-2 (designation AG-2 BI). Subsets -2-3 and -2-4 show very weak bridging-type anastomosis reactions with all other subsets of AG-2 and thus may be candidates for independent AG status. Grouping within AG-2 based on rDNA-ITS sequences was consistent with the abovementioned subsets. However, grouping based on virulence as measured herein does not conform to established grouping patterns within AG-2 and does not seem useful as a group-defining criterion. A broad range of damage was observed among members of the most virulent subsets (-2-1, -2-2 IIIB, -2-2 IV, and -2-4), whereas other subsets (-2 BI, -2-2 LP, and -2-3) were similar to one another in causing a minimal level of damage. Group-specific primer pairs for each of the seven subsets of AG-2 were designed based on the abovementioned rDNA-ITS sequences. Primer pairs proved dependable and subset specific in polymerase chain reaction amplifications of purified genomic DNA from 109 isolates of R. solani and two isolates of binucleate Rhizoctonia. These primers will provide a simple and useful method for subset-specific characterization within AG-2 if further critical evaluations confirm their specificity.

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Phylogenetic relationships of species in Pseudoroegneria (Poaceae: Triticeae) and related genera inferred from nuclear rDNA ITS (internal transcribed spacer) sequences

Biologia ◽

10.2478/s11756-008-0091-2 ◽

2008 ◽

Vol 63 (4) ◽

Cited By ~ 16

Author(s):

Haiqing Yu ◽

Xing Fan ◽

Chun Zhang ◽

Chunbang Ding ◽

Xiaoli Wang ◽

...

Keyword(s):

Phylogenetic Relationships ◽

Internal Transcribed Spacer ◽

New Genus ◽

The Other ◽

Its Sequences ◽

Agropyron Cristatum ◽

Tetraploid Species ◽

Nuclear Rdna ◽

Rdna Its ◽

Internal Transcribed Spacer Sequences

AbstractTo evaluate the phylogenetic relationships of species in Pseudoroegneria and related genera, the nuclear ribosomal internal transcribed spacer (ITS) sequences were analyzed for eighteen Pseudoroegneria (St), two Elytrigia (E e St), two Douglasdeweya (StP), three Lophopyrum (E e and E b), three Agropyron (P), two Hordeum (H), two Australopyrum (W) and two Psathyrostachys (Ns) accessions. The main results were: (i) Pseudoroegneria gracillima, P. stipifolia, P. cognata and P. strigosa (2x) were in one clade, while P. libanotica, P. tauri and P. spicata (2x) were in the other clade, indicating there are the differentiations of St genome among diploid Pseudoroegneria species; (ii) P. geniculata ssp. scythica, P. geniculata ssp. pruinifera, Elytriga caespitosa and Et. caespitosa ssp. nodosa formed the E e St clade with 6-bp indel in ITS1 regions; and (iii) Douglasdeweya wangii, D. deweyi, Agropyron cristatum and A. puberulum comprised the P clade. It is unreasonable to treat P. geniculata ssp. scythica and P. geniculata ssp. pruinifera as the subspecies of P. geniculata, and they should be transferred to a new genus Trichopyrum, which consists of species with E e St genomes. It is also suggested that one of the diploid donor of D. wangii and D. deweyi is derived from Agropyron species, and it is reasonable to treat tetraploid species with StP genomes into Douglasdeweya.

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Primers based on specific rDNA-ITS sequences for PCR detection of Rhizoctonia solani, R. solani AG 2 subgroups and ecological types, and binucleate Rhizoctonia

Mycological Research ◽

10.1017/s0953756299001355 ◽

2000 ◽

Vol 104 (3) ◽

pp. 281-285 ◽

Cited By ~ 43

Author(s):

O. Salazar ◽

M.C. Julian ◽

V. Rubio

Keyword(s):

Rhizoctonia Solani ◽

Pcr Detection ◽

Its Sequences ◽

Binucleate Rhizoctonia ◽

Rdna Its ◽

Rdna Its Sequences ◽

Ecological Types

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Comparison of rDNA-ITS Sequences between Potato and Tobacco Strains in Rhizoctonia solani AG-3

Journal of General Plant Pathology ◽

10.1007/pl00012917 ◽

2000 ◽

Vol 66 (1) ◽

pp. 2-11 ◽

Cited By ~ 46

Author(s):

Shiro KUNINAGA ◽

Donald E CARLING ◽

Toru TAKEUCHI ◽

Ryozo YOKOSAWA

Keyword(s):

Rhizoctonia Solani ◽

Its Sequences ◽

Rdna Its ◽

Rdna Its Sequences

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STUDY THE VARIATION OF SUGAR BEET Rhizoctonia solani BY PCR (rDNA-ITS SEQUENCES)

Journal of Plant Protection and Pathology ◽

10.21608/jppp.2009.166775 ◽

2009 ◽

Vol 34 (4) ◽

pp. 3853-3868

Author(s):

Mona Nour-El-Din ◽

M. Saleh ◽

E. Hafez

Keyword(s):

Sugar Beet ◽

Rhizoctonia Solani ◽

Its Sequences ◽

Rdna Its ◽

Rdna Its Sequences

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Characterization of Japanese Rhizoctonia solani AG-2-1 isolates using rDNA-ITS sequences, culture morphology, and growth temperature

Journal of General Plant Pathology ◽

10.1007/s10327-018-0808-1 ◽

2018 ◽

Vol 84 (6) ◽

pp. 387-394 ◽

Cited By ~ 2

Author(s):

Tomoo Misawa ◽

Daisuke Kurose ◽

Manami Mori ◽

Takeshi Toda

Keyword(s):

Rhizoctonia Solani ◽

Growth Temperature ◽

Its Sequences ◽

Rdna Its ◽

Rdna Its Sequences ◽

Culture Morphology

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Cortinarius alpinus as an example for morphological and phylogenetic species concepts in ectomycorrhizal fungi

Sommerfeltia ◽

10.2478/v10208-011-0009-1 ◽

2008 ◽

Vol 31 (1) ◽

pp. 161-177 ◽

Cited By ~ 8

Author(s):

U. Peintner

Keyword(s):

Ectomycorrhizal Fungi ◽

Related Species ◽

Dry Weight ◽

Species Concepts ◽

Its Sequences ◽

Phylogenetic Species ◽

Closely Related Species ◽

Rdna Its ◽

Rdna Its Sequences ◽

Distinguishing Character

Cortinarius alpinus as an example for morphological and phylogenetic species concepts in ectomycorrhizal fungiExtensive morphological and molecular analyses of closely related species from alpine, subalpine and montane habitats should enable a comparison of ecological, morphological and phylogenetic species concepts in ectomycorrhizal mushrooms. One fundamental question of this study was whether alpine species really exist, and which criteria, besides the specific habitat, could reliably be used for the de-limitation of such taxa. For this reason, 56 rDNA ITS sequences were generated or downloaded from GenBank for 10 closely related species of Cortinarius subgenus Myxacium, section Myxacium. Several collections were sequenced for each of the following taxa: Cortinarius absarokensis, C. alpinus, C. favrei, C. fennoscandicus, C. grallipes, C. mucosus, C. muscigenus, C. septentrionalis, C. trivialis and C. vernicosus. Moreover, spore statistics were carried out for 38 collections of alpine and subalpine taxa. These data provide clear evidence for C. favrei being a synonym of C. alpinus. C. absarokensis and C. alpinus can clearly be delimited based on pileus diameter and average dry weight per basidiome, even in overlapping habitats, but spore size and shape is not a good distinguishing character. Phylograms have very short branches, and base differences between ITS sequences are generally very low in this group, and give no resolution for the included taxa of this section. Based on these results, species concepts of ectomycorrhizal mushrooms are discussed in detail.

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