scholarly journals Differentiation of Rhizoctonia spp. Based on their antigenic properties

2002 ◽  
Vol 47 (2) ◽  
pp. 137-147
Author(s):  
Ivana Vico ◽  
Branka Krstic ◽  
Natasa Dukic
Keyword(s):  
Anastomosis Group ◽  
Serological Relationship ◽  
Binucleate Rhizoctonia ◽  
Anastomosis Groups ◽  
Potato Plants ◽  
Antigenic Properties ◽  
Cross Absorption ◽  
Fusarium Sp ◽  
Polyclonal Antisera ◽  
Taxonomic Groups

Antigenic properties and serological relationship was investigated in binucleate and multinucleate Rhizoctonia spp. isolates from strawberries soybean, alfalfa and potato plants from Serbia, from Spain, anastomosis group testers and in strawberry roots inoculated with binucleate Rhizoctonia AG A and AG I. Two polyclonal antisera, unabsorbed and cross absorbed, were used in dot-immunobinding assay for these investigations. Antisera were produced against mycelial antigens of two isolates, which belong to different anastomosis groups (AG) of binucleate Rhizoctonia - AG A and AG I. Both unabsorbed antisera reacted positively with all tested Rhizoctonia spp. isolates, and the reaction was absent with control isolates (Pythium sp. Agaricus sp. and Fusarium sp). The results prove a close serological relationship among Rhizoctonia spp. isolates, and diversity between Rhizoctonia spp. and isolates from different taxonomic groups. Also, both unabsorbed antisera reacted with higher intensity with closely related antigens (belonging to the same AG) than with ones from another AG of binucleate Rhizoctonia or R. solani (multinucleate Rhizoctonia). After cross absorption specificity of the antisera was enhanced, especially with the antiserum raised against mycelial proteins of binucleate Rhizoctonia AG I. This antiserum reacted positively only with antigens from the same AG, after cross absorption with antigens from AG A of binucleate Rhizoctonia and from R. solani AG 2-2. It proved to be specific to AG I of binucleate Rhizoctonia, and able to differentiate isolates of this AG from others. In this way the serological homology among isolates of one AG was proven, and also the diversity among isolates which belong to different AGs of binucleate Rhizoctonia as well as isolates of R. solani.

scholarly journals Anastomosis Groups and Pathogenicity of Rhizoctonia solani and Binucleate Rhizoctonia from Potato in South Africa

Plant Disease ◽  
2015 ◽  
Vol 99 (12) ◽  
pp. 1790-1802 ◽  
Author(s):  
N. Muzhinji ◽  
M. Truter ◽  
J. W. Woodhall ◽  
J. E. van der Waals
Keyword(s):  
South Africa ◽  
Rhizoctonia Solani ◽  
Stem Canker ◽  
Black Scurf ◽  
Bootstrap Support ◽  
Internal Transcribed Spacer Region ◽  
Binucleate Rhizoctonia ◽  
Anastomosis Groups ◽  
Potato Plants ◽  
Comprehensive Survey

A survey of anastomosis groups (AG) of Rhizoctonia spp. associated with potato diseases was conducted in South Africa. In total, 112 Rhizoctonia solani and 19 binucleate Rhizoctonia (BNR) isolates were recovered from diseased potato plants, characterized for AG and pathogenicity. The AG identity of the isolates was confirmed using phylogenetic analysis of the internal transcribed spacer region of ribosomal DNA. R. solani isolates recovered belonged to AG 3-PT, AG 2-2IIIB, AG 4HG-I, AG 4HG-III, and AG 5, while BNR isolates belonged to AG A and AG R, with frequencies of 74, 6.1, 2.3, 2.3, 0.8, 12.2, and 2.3%, respectively. R. solani AG 3-PT was the most predominant AG and occurred in all the potato-growing regions sampled, whereas the other AG occurred in distinct locations. Different AG grouped into distinct clades, with high maximum parsimony and maximum-likelihood bootstrap support for both R. solani and BNR. An experiment under greenhouse conditions with representative isolates from different AG showed differences in aggressiveness between and within AG. Isolates of AG 2-2IIIB, AG 4HG-III, and AG R were the most aggressive in causing stem canker while AG 3-PT, AG 5, and AG R caused black scurf. This is the first comprehensive survey of R. solani and BNR on potato in South Africa using a molecular-based approach. This is the first report of R. solani AG 2-2IIIB and AG 4 HG-I causing stem and stolon canker and BNR AG A and AG R causing stem canker and black scurf on potato in South Africa.

scholarly journals Controlling Rhizoctonia Damping-off of Chinese Mustard by Using Endomycorrhizal Rhizoctonia spp. Isolated from Orchid Mycorrhizae

Plant Disease ◽  
2016 ◽  
Vol 100 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Jr-Hau Jiang ◽  
Si-Loi Tam ◽  
Takeshi Toda ◽  
Lung-Chung Chen
Keyword(s):  
Phylogenetic Analysis ◽  
Rhizoctonia Solani ◽  
Disease Severity ◽  
Anastomosis Group ◽  
Effective Strategy ◽  
Damping Off ◽  
Binucleate Rhizoctonia ◽  
Orchid Mycorrhizae ◽  
Almost All ◽  
Test Plants

Inoculation of hypovirulent Rhizoctonia spp. has been recognized as an effective strategy for protecting plants against damping-off caused by pathogenic Rhizoctonia spp. In this study, endomycorrhizal Rhizoctonia spp. isolated from fungal pelotons in orchid plants were used for controlling Rhizoctonia damping-off of Chinese mustard. According to phylogenetic analysis and anastomosis group (AG) determination, the virulence of three isolates of multinucleate Rhizoctonia solani in AG-6; eight isolates of binucleate Rhizoctonia in AG-A, AG-B, AG-G, AG-P, and AG-R; and two isolates of binucleate R. repens were evaluated using test plants. All isolates, except that in AG-R, caused low disease severity in 10-day-old radish (0.10 to 0.61), cucumber (0.28 to 0.54), and Chinese mustard (0.18 to 0.65). By contrast, pathogenic isolates in AG-4 killed almost all test plants with symptoms of collapsed hypocotyl and wilted leaves (0.88 to 0.96). Of the 13 endomycorrhizal Rhizoctonia isolates assessed, AG-P isolates Cno10-3 and CalS1-2 provided 91 and 100% protection, respectively, against R. solani AG-4 in 26-day-old Chinese mustard. This study revealed that endomycorrhizal Rhizoctonia spp. in orchid have the potential to biologically control damping-off of Chinese mustard.

scholarly journals First Report of Root Rot Caused by Binucleate Rhizoctonia Anastomosis Group F on Musa spp.

Plant Disease ◽  
2011 ◽  
Vol 95 (4) ◽  
pp. 490-490
Author(s):  
J. Yin ◽  
D. Koné ◽  
M. Rodriguez-Carres ◽  
M. A. Cubeta ◽  
L. L. Burpee ◽  
...  
Keyword(s):  
Root Rot ◽  
Lateral Roots ◽  
Anastomosis Group ◽  
Molecular Characteristics ◽  
First Report ◽  
Binucleate Rhizoctonia ◽  
Musa Spp ◽  
University Of Georgia ◽  
Its Regions ◽  
The University

A research program was initiated at the University of Georgia in 2003 to identify banana cultivars suitable for production in the coastal and southern areas of the state. During a root disease survey conducted in October 2007 on bananas (Musa spp.) grown at the University of Georgia Bamboo Farm and Coastal Gardens in Savannah, GA, root lesions and root rot were observed on banana cvs. Gold Finger, Kandarian, and Manzano. Root lesions were dark brown to black and irregular in shape, with partial or entire roots affected. Lateral roots and outer layers of cord roots (roots arising from interior layers of the corm) of infected plants were blackened and rotted. Diseased root samples were collected from three plants of each cultivar, surface sterilized with 0.6% sodium hypochlorite, and placed on tannic acid benomyl agar (TABA). Pure cultures of the fungus consistently associated with diseased tissue were obtained by subculturing hyphal tips on TABA. Mycelia of the fungus on potato dextrose agar (PDA) were light to deep brown and the hyphae tended to branch at right angles. A septum was present in each hyphal branch near the point of origin and a slight constriction at the branch was observed. The hyphae of two isolates were stained with 0.6% phenosafranin and 3% KOH and binucleate hyphal cells were observed. On the basis of these morphological features, the isolates appeared to be binucleate Rhizoctonia anamorphs (teleomorph Ceratobasidium Rogers). For molecular identification, the internal transcribed spacer (ITS) regions and the 5.8S gene from rDNA of the isolates were cloned and sequenced (GenBank Accession No. HQ168370). The ITS regions (775 bp) were 100% identical between the two isolates and 99% identical to Ceratobasidium sp. AG-F strain SIR-1 isolated from sweet potato in Japan (GenBank Accession No. AF354085). The anastomosis group of the isolates was confirmed by pairing with strain SIR-1 on PDA. On the basis of morphological and molecular characteristics and the anastomosis assay, the two isolates were identified as a Ceratobasidium sp. AG-F (1–3). Pathogenicity assays were conducted by inoculating banana plants (cv. Golden pillow, synonym = Manzano) grown in pots under greenhouse conditions (25 to 27°C). Twenty wheat seeds infested with each isolate were placed uniformly around each plant at a depth of 10 cm in the soil. The plants were incubated in the greenhouse and the roots were examined 2 months after inoculation. Brown-to-black lesions and root rot, identical to symptoms associated with field banana roots, were observed on all inoculated plants but not on the noninoculated control plants. The fungus was reisolated from affected root samples and the identity was confirmed by morphological and molecular characteristics and the anastomosis assay. To our knowledge, this is the first report of banana root rot caused by binucleate Rhizoctonia anastomosis group F. With the increased interest in producing bananas for food and ornamental purposes, the occurrence of Ceratobasidium root rot on bananas needs to be considered when designing disease management programs and searching for suitable cultivars for banana production. References: (1) L. L. Burpee et al. Mycologia 70:1281, 1978. (2) D. González et al. Mycologia 93:1138, 2001. (3) B. Sneh et al. Identification of Rhizoctonia Species. The American Phytopathological Society, St. Paul, MN. 1991.

scholarly journals In vitro evaluation of fungicidal responses on the growth of pathogenic Rhizoctonia solani Kuhn, antagonistic binucleate Rhizoctonia and Trichoderma harzianum Rifai

1970 ◽  
Vol 39 (1) ◽  
pp. 107-110
Author(s):  
Md Maniruzzaman Khandaker ◽  
Md Khurshed Alam Bhuiyan ◽  
Abul Khair
Keyword(s):  
Boric Acid ◽  
Rhizoctonia Solani ◽  
Key Words ◽  
Trichoderma Harzianum ◽  
Stem Canker ◽  
Black Scurf ◽  
Binucleate Rhizoctonia ◽  
Crop Fields ◽  
Potato Plants

Two pathogenic isolates of Rhizoctonia solani Kuhn causing stem canker/black scurf disease of potato plants and four antagonist isolates, two of binucleate Rhizoctonia and two of Trichoderma harzianum Rifai were isolated from crop fields and evaluated in vitro for their fungicidal responses against eight fungicides. Vitavax was effective in inhibiting the growth of R. solani and binucleate Rhizoctonia but it did not inhibit the growth of T. harzianum at 100 ppm concentration. Terraclor Super X, Dithane M 45 and Boric acid are the fungicides which at 100 ppm concentration did not inhibit the growth of antagonist isolates of T. harzianum and binucleate Rhizoctonia but inhibited the growth of isolates of R. solani to some extent. The in vitro findings suggest that any one of these three fungicides along with antagonist isolates of binucleate Rhizoctonia and T. harzianum can be used as biocontrol agents to reduce soil borne inocula of R. solani. Key words: Rhizoctonia solani; Binucleate; Trichoderma harzianum; Fungicide DOI: 10.3329/bjb.v39i1.5534Bangladesh J. Bot. 39(1): 107-110, 2010 (June)

scholarly journals Serological and biochemical distinguishing of Pseudomonas syringae pathovars on peas

1999 ◽  
Vol 35 (No. 3) ◽  
pp. 79-84 ◽  
Author(s):  
I. Pánková ◽  
B. Kokošková
Keyword(s):  
Pseudomonas Syringae ◽  
Serological Test ◽  
Double Diffusion ◽  
Bacterial Cells ◽  
Serological Tests ◽  
Cross Absorption ◽  
Polyclonal Antisera ◽  
Pseudomonas Syringae Pathovars ◽  
High Level ◽  
Heterologous Antigens

Polyclonal antisera to detect and determine two related pathovars, Pseudomonas syringae pv. pisi and Pseudomonas syringae pv. syringae, were prepared Untreated bacterial cells, or fixed by formaldehyde or glutaraldehyde were used as antigens. After cross-absorption with heterologous antigens, antisera revealed a high level of specificity in slide agglutination, Ouchterlony gel double-diffusion and in DAS-ELISA and PTA-ELISA. Each of 14 P s. pisi prepared polyclonal antisera could detect and deter­ mine all strains of P s. pisi, regardless of race. PTA-ELISA was the most appropriate serological test to distinguish Pseudomonas syringae pathovars on peas. Most of the P s. pisi strains from foreign collections were in serological tests confirmed asP. s. pisi, while most of the Czech strains suspected as P s. pisi were determined as P s. syringae strains. The principal biochemical reaction, i.e., use of DL-homoserine as a carbon source to grow P s. pisi but not P s. syringae , was proved not to be sufficiently reliable to distinguish both pathovars.

scholarly journals Characterization of Rhizoctonia spp. Causing Root and Stem Rot of Miniature Rose

Plant Disease ◽  
2001 ◽  
Vol 85 (11) ◽  
pp. 1200-1205 ◽  
Author(s):  
A. Priyatmojo ◽  
Y. Yotani ◽  
K. Hattori ◽  
K. Kageyama ◽  
M. Hyakumachi
Keyword(s):  
Root Rot ◽  
Rosa Hybrida ◽  
Stem Rot ◽  
Binucleate Rhizoctonia ◽  
Anastomosis Groups ◽  
Different Ages ◽  
Gifu Prefecture

Root and stem rot of miniature rose (Rosa hybrida L.) was observed in commercial glasshouse-grown roses in Gifu prefecture, Japan, during the summer and fall of 1997 and 1998. One hundred and fifty-three isolates of Rhizoctonia spp. were obtained from infected roots and stems. Of the 153 isolates, 9 had binucleate and 144 had multinucleate vegetative hyphal cells. Binucleate Rhizoctonia failed to anastomose with tester isolates of anastomosis groups (AG)-A through -S (not including AG-J and AG-M). Of 144 isolates identified as R. solani, 83.3% were AG 2-2 IIIB and 16.7% were AG 4 HG-I. Five isolates from each group caused severe rot and mortality on cuttings during rooting. Pathogenicity of Rhizoctonia spp. varied on three different ages of miniature roses cv. Silk. Isolates of AG 4 HG-I caused root and stem rot and mortality on 15-, 25-, and 40-day-old plants, whereas isolates of AG-2-2 IIIB caused root and stem rot and mortality on 15- and 25-day-old plants, but light root rot on 40-day-old plants. Isolates of binucleate Rhizoctonia caused root and stem rot and mortality only on 15-day-old plants.

scholarly journals Characterization of a New Anastomosis Group (AG-W) of Binucleate Rhizoctonia, Causal Agent for Potato Stem Canker

Plant Disease ◽  
2015 ◽  
Vol 99 (12) ◽  
pp. 1757-1763 ◽  
Author(s):  
Y. G. Yang ◽  
C. Zhao ◽  
Z. J. Guo ◽  
X. H. Wu
Keyword(s):  
Fragment Length Polymorphism ◽  
Stem Canker ◽  
Anastomosis Group ◽  
Northeastern China ◽  
Binucleate Rhizoctonia ◽  
Rdna Its ◽  
Its Regions ◽  
Pathogenicity Tests ◽  
Reference Strains

Two binucleate Rhizoctonia (BNR) isolates were recovered from potato cankered stems in Heilongjiang Province, northeastern China. Their cultural appearance on potato dextrose agar remained whitish as the cultures aged. White monilioid cells formed in the fluffy aerial hyphae, whereas no sclerotia appeared during the incubation. The two isolates could anastomose with each other, but they failed to anastomose with reference strains of BNR from AG-A to AG-Q, and AG-U. Analyses of restriction fragment length polymorphism (RFLP) of internal transcribed spacer of ribosomal DNA (rDNA-ITS) regions confirmed that these two isolates differed from the reference strains. The phylogenetic tree based on the sequences of rDNA-ITS regions showed that they were located in a distinct clade from other BNR AGs. These collective results suggested that the isolates recovered from potato in this study belonged to a new BNR AG designated as AG-W. Pathogenicity tests under glasshouse conditions revealed that both isolates were able to cause brown, dry, and slightly sunken lesions on potato subterranean stems. To our knowledge, this is the first report of the AG-W causing potato disease in China as well as worldwide.

Relationship of binucleate Rhizoctonia isolates used for biocontrol of rhizoctonia crown rot of sugar beet to anastomosis systems

1991 ◽  
Vol 37 (5) ◽  
pp. 339-344 ◽  
Author(s):  
Leonard J. Herr
Keyword(s):  
Sugar Beet ◽  
Root Rot ◽  
Anastomosis Group ◽  
The Other ◽  
Crown Rot ◽  
Considerable Heterogeneity ◽  
Binucleate Rhizoctonia ◽  
Crown And Root Rot ◽  
Relationship Of ◽  
Intraspecific Group

The relationships of 10 binucleate Rhizoctonia isolates used as biocontrol agents of rhizoctonia crown and root rot of sugar beet in Ohio to described binucleate Rhizoctonia anastomosis systems were investigated. Ten Ohio binucleate Rhizoctonia (Ohio BNR) isolates, paired in all combinations, cross anastomosed with one another, indicating that all belong to the same anastomosis group. Four representative Ohio BNR isolates failed to anastomose with any tester isolates of the Ceratobasidium anastomosis grouping system, indicating that none belong in that system. However, all 10 Ohio BNR isolates anastomosed with an AG-B (o) tester isolate (binucleate Rhizoctonia anastomosis grouping system), indicating that the Ohio agents belong in this anastomosis grouping system and to the (o) intraspecific group of AG-B. None of the Ohio BNR isolates anastomosed with either of the other two intraspecific group tester isolates (AG-Ba, AG-Bb) of the AG-B group. Moreover, the AG-B intraspecific group tester isolates, AG-Ba, AG-Bb, AG-B (o), self-anastomosed but did not cross anastomose with one another. Variations in cultural characteristics noted among the 10 Ohio BNR isolates indicated that considerable heterogeneity exists within these AG-B (o) isolates. Key words: binucleate Rhizoctonia, anastomosis, rhizoctonia crown rot, sugar beet.

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