Characterization of Cell Wall Degrading Enzymes of Rhizoctonia solani AG-3 from Tobacco Target Spot

2014 ◽  
Vol 1010-1012 ◽  
pp. 1161-1164
Author(s):  
Yan Qin Zhao ◽  
Yuan Hua Wu ◽  
Xiu Xiang Zhao ◽  
Meng Nan An ◽  
Jian Guang Chen ◽  
...  

Rhizoctonia solaniKühn is a causal pathogen responsible for many types of plant disease worldwide and a major soilborne fungal pathogen that severely impairs yield and quality of tobacco worldwide. Activities, pathogenicity of the cell wall-degrading enzymes produced by theRhizoctoniasolanifrom tobacco target spot disease both in liquid medium and in tobacco tissue were studied. The result showed thatR.solanifrom tobacco can produce pectinase and cellulase both in vitro and vivo, and the activity of PG and PMG was the highest in vitro. The activity of Cx and β-glucosidase was the highest in vivo, and enzyme production ability of strong pathogenicity strains is stronger than the weak pathogenicity strains in vitro.

1996 ◽  
Vol 74 (9) ◽  
pp. 1407-1415 ◽  
Author(s):  
Mohamed S. El-Abyad ◽  
Amira M. Abu-Taleb ◽  
Tarek Abdel-Mawgood

Pyradur applied to soil at 0.6–2.4 µg∙g−1 active ingredients suppressed infection of three sugarbeet cultivars by Rhizoctonia solani and Sclerotium rolfsii. In the absence of Pyradur, R. solani was more virulent than S. rolfsii against 'Raspoly' and 'TOP', whereas S. rolfsii was more virulent than R. solani against ‘Tribel’. Virulence was directly correlated with the activities of cell wall degrading enzymes produced by mese pathogens in vivo and on cell walls in vitro. Reduced virulence of R. solani and S. rolfsii under Pyradur stress was due to decreased inoculum potential of the two pathogens at the utilized concentrations of herbicide in situ and to reduced production of cell wall degrading enzymes in vitro and in host tissues. In addition, shifts in the pH of cell wall amended media, because of changes in the nature of metabolic products of the pathogens under Pyradur stress, suggest possible repression or stimulation of the activity of the enzymes involved in degradation in vivo, of which cellulase and polygalacturonase are favoured by acid conditions, and galactanase, mannase, and pectate lyase are favoured by alkaline conditions. Keywords: sugarbeet, Rhizoctonia solani, Sclerotium rolfsii, Pyradur, metolachlor, chloridazon, growth activities, pathogenicity, virulence, cell wall enzymes.


2013 ◽  
Vol 726-731 ◽  
pp. 4321-4325 ◽  
Author(s):  
Yan Qin Zhao ◽  
Yuan Hua Wu ◽  
Ying Fu ◽  
Meng Nan An ◽  
Jian Guang Chen ◽  
...  

Rhizoctonia solani Kühn is the causal pathogen of tobacco target spot, a serious fungal disease of tobacco that severely impairs yield and quality in northeast China. The objective of this study was to characterize isolates ofR. solanifrom tobacco in China. Among 58Rhizoctoniaisolates examined, all of them were multinucleate. Phylogenetic analyses and hyphal anastomosis criteria suggest that the isolates belonged toR. solanianastomosis group (AG) 3. Target spot isolates from Liaoning province formed a single phylogenetic group together with tomato isolates ofR. solaniAG-3 from Japan and are more closely related toR. solaniAG-3 isolates in tomato and potato than that in tobacco from USA. Pathogenicity test for each isolates was fulfilled using a method of inoculating tobacco leaves from plants grown for 8 weeks (cv. NC89).


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5580 ◽  
Author(s):  
Cai Yun Xue ◽  
Ru Jun Zhou ◽  
Yuan Jie Li ◽  
Di Xiao ◽  
Jun Fan Fu

Rhizoctonia solanicauses the disease peanut sheath blight, involving symptoms of maceration and necrosis of infected tissue, mainly caused by cell-wall-degrading enzymes (CWDEs). This study investigated the production of CWDEs including polygalacturonase (PG), polymethyl-galacturonase (PMG), cellulase (Cx) and β-glucosidase byR. solaniin vitro (in liquid culture) and in vivo (in peanut plants). Significant PG, PMG, Cx and β-glucosidase activities were detected in infected tissues including stalk and leaves of Baisha and Silihong peanut cultivars. Extracts of healthy tissue showed little or no such activities. In shaken liquid cultures ofR. solaniin medium containing pectin or pectin plus carboxymethyl cellulose (CMC) as the carbon source(s), PG and PMG were notably active. Significant Cx activity was detected in cultures with CMC or pectin plus CMC as the carbon source(s). However, only a very low level of β-glucosidase activity was observed in cultures with any of the tested carbon sources. An increase of pH was recorded in decayed peanut tissues and liquid culture filtrates; the filtrate pH and fungal growth positively correlated. The fungal growth and/or pH were important factors for the production of PG, PMG and Cx in culture with pectin plus CMC as the carbon source. A single active PG isozyme with isoelectric point around 9.2 was detected in culture filtrates and in infected peanut tissues by the method of isoelectric focusing electrophoresis. The crude enzymes extracted from liquid culture ofR. solaniinduced decay of healthy peanut leaves.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Feng He ◽  
Katja Machemer-Noonan ◽  
Philippe Golfier ◽  
Faride Unda ◽  
Johanna Dechert ◽  
...  

Abstract Background Understanding lignin biosynthesis and composition is of central importance for sustainable bioenergy and biomaterials production. Species of the genus Miscanthus have emerged as promising bioenergy crop due to their rapid growth and modest nutrient requirements. However, lignin polymerization in Miscanthus is poorly understood. It was previously shown that plant laccases are phenol oxidases that have multiple functions in plant, one of which is the polymerization of monolignols. Herein, we link a newly discovered Miscanthus laccase, MsLAC1, to cell wall lignification. Characterization of recombinant MsLAC1 and Arabidopsis transgenic plants expressing MsLAC1 were carried out to understand the function of MsLAC1 both in vitro and in vivo. Results Using a comprehensive suite of molecular, biochemical and histochemical analyses, we show that MsLAC1 localizes to cell walls and identify Miscanthus transcription factors capable of regulating MsLAC1 expression. In addition, MsLAC1 complements the Arabidopsis lac4–2 lac17 mutant and recombinant MsLAC1 is able to oxidize monolignol in vitro. Transgenic Arabidopsis plants over-expressing MsLAC1 show higher G-lignin content, although recombinant MsLAC1 seemed to prefer sinapyl alcohol as substrate. Conclusions In summary, our results suggest that MsLAC1 is regulated by secondary cell wall MYB transcription factors and is involved in lignification of xylem fibers. This report identifies MsLAC1 as a promising breeding target in Miscanthus for biofuel and biomaterial applications.


1990 ◽  
Vol 38 (3B) ◽  
pp. 407-422
Author(s):  
A. Steg ◽  
S.F. Spoelstra ◽  
J.M. van der Meer ◽  
V.A. Hindle

A total of 50 grass silages were tested in digestibility trials using Texel wethers. The feed silages were wilted of varying DM contents and treated with cell-wall degrading enzymes. The accuracy of feed evaluation was studied using laboratory analyses, including cell-wall analyses, incubation in vitro with rumen fluid and the enzymic procedure. A comparison was made between these results and the current and recently suggested procedures for prediction of digestibility of grass silage. (Abstract retrieved from CAB Abstracts by CABI’s permission)


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