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[Objective] Screening and obtaining the antagonistic actinomycetes with significant antifungal activity against the pathogen of Sarcandra glahra, for the theoretical foundation for biological control of anthracnose. [Method] The actinomycetes were isolated by root soil of health S. glabra using spread plate method, and the highest antifungal activity of strain was screened by the method of plate confrontation, and using in vitro leaf stabbing wound inoculation method to screen the control effect of antagonistic strain against anthracnose of S. glabra. Moreover, the species was identified through morphological characterization and 16 S rDNA sequence by establishing a phylogenetic tree to analyze its classification status. [Result] By plate confrontation and antibacterial spectrum test, the results showed that the JT-2 F was isolated from soil had the highest antagonistic effect against anthracnose of S. gfubra, resulting in the hyphae being swelled and deformed, the antagonism rate was 86. 75%. Antibacterial spectrum tests showed it had antagonistic activities to 14 plant pathogens, whose average inhibition rate was 81. 50%. Based on morphological characters and 16S rDNA sequence analysis, strain JT-2F was identified as Streptomyces tsukiyonensis. In vitro control effect test results showed that the fermentation broth of JT-2F strain had 87. 32 % control effect on anthracnose of S. glabra. [Conclusion ] JT-2F has development and application potential as biocontrol material for anthracnose of S. glabra. [ABSTRACT FROM AUTHOR]

【Objective】The diversity of endophytic fungi of medicinal plants of Sarcandra glabra was analyzed,and the strains with strong antifungal activity were screened to lay a foundation for the search for new antimicrobial resources.【Method】Endophytic fungi with strong antimicrobial activities were isolated from different tissues of S. glabra by plate confrontation method,and their species was identified by combining morphological characteristics and ITS sequence to screen out endophytic fungi with strong antimicrobial activities.【Result】One hundred and eleven of various endophytes were obtained from the different organizations of S. glabra,forty-two strains of different morphological types were selected for molecular identification,which belonged to nine orders and twenty genera,twenty-eight species. The RJ-1 and JJ-1 had remarkable antimicrobial activities to fifteen pathogenic fungi. Morphological and molecular identification showed that RJ-1 and JJ-1 were Phomopsis heveicola and Neofusicoccum parvum,respectively. Their antifungal activity to seven pathogens including Botrytis sp.,Fusarium solani,Colltetorrichum gloeosporioides of Panax notoginseng,Colltetorrichum sp. of Musa,Phoma sp. of Blumea balsamifera,Alternaria sp. of Picria felterrae,Colletotrichum dematium of S. glabra was over 80 %,with strong antifungal broad-spectrum.【Conclusion】The endophytic fungi in S. glabra were diverse and rich. Some strains such as RJ-1 and JJ-1 deserve further research as an alternative antimicrobial resource. [ABSTRACT FROM AUTHOR]

【Objective】Biological control effects of Bacillus methylotrophicus strain bjq-a against on Siraitia grosvenorii leaf blight was tested to provide reference for green control of S. grosvenorii leaf blight and development of antibiological inoculant.【Method】The antagonism of bjq-a on Stagonosporopsis cucurbitacearum were studied via the plate confrontation test, the hyphae mixed fermentation cultivation test, the concave slide method and microscope examination. Mycelial morphology, mycelial growth inhibition rate and spore germination inhibition rate were detected.The control efficacy against S.cucurbitacearum on S. grosvenorii was analyzed by inoculation of leaves in vitro. By detecting the contents of protease,cellulase and chitinase in bjq-a fermentation liquid,the antibacterial mechanism of bjq-a was preliminarily studied.【Result】The results showed that bjq-a had obvious antagonistic activity against S. cucurbitacearum,after 30 days confront culture,the growth inhibition rate of bjq-a against S. cucurbitacearum was 62.5 %. 40 % and 20 % bjq-a fermentation liquid had strong antimicrobial effects,the growth inhibition rates were 99.5 % and 96.2 % respectively.50 % bjq-a fermentation could inhibit the spore germination with the inhibitory ratio of 90.5 %. Hyphae and spore treated by fermentation liquid of bjq-a were swelled and deformed. When 20 % bjq-a fermentation liquid was used to control S. grosvenorii leaf blight, the result showed that the onset time was delayed for 1 day,the incidence of diseases was reduced by 60.0 %,the enlargement of lesions was inhibited,and the inhibition rate was 82.2 %.The result of antibiosis mechanism indicated that strain bjq-a could produce protease,chitinase and cellulose, and was one of the mechanisms that produced antagonistic activity.【Conclusion】This study indicated that bjq-a with broad spectrum antifungal activity had brilliant control efficacy on S. grosvenorii leaf blight.The strain could be exploited so as to become effective biological agents in the future. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to screen, isolate and identify the high-yield lignocellulose-degrading endophytic fungi from Taxillus chinensis (DC.) seeds, and provide technical support for the acquisition of lignocellulose-degrading enzymes with strong capacity and T. chinensis artificial cultivation. [Method] The endophytic fungi of T. chinensis seeds were isolated by conventional tissue separation method. Wheat bran was used as substrate for lignin biomass. The activities of laccase, lignin peroxidase, manganese peroxidase and cellulose degrading enzyme were determined by ABTS method, veratrol method, phenol red method and cellulase (CL) activity detection kit. The strains with strong lignocellulosic degradation ability were screened and their classification status was determined according to morphological characteristics and phylogenetic tree analysis. (Result) Four high-yielding lignocellulosic degrading strains (15H3, 2013, 106 and 10y11) were selected from the 57 strains of endophytic fungi from T. chinensis seeds. Among them, the lignin peroxidase activity of strain 15H3 and the manganese peroxidase activity of strain 2013 reached the peak when cultured in the crude enzyme solution of endophytic fungi from T. chinensis seeds for 11 days, they were 7.14 and 11.69 U/mL, respectively. At 9 days, the laccase activity of strain 106, cellulase activity of strain 2013, the manganese peroxidase activity of strain 10y11 were the highest, which were 57.98,0.32 and 8.56 U/mL, respectively. By morphological observation and molecular biology identification, strain 15H3 and 2013 could be identified as Pestalotiopsis arceuthobii and Coniella pseudogranati, respectively. Strains 106 and 10y11 were identified as Fusarium incarnatum. [Conclusion] The endophytic fungi P. arceuthobii, C. pseudogranati and F. incarnatum with high production of lignocellulosic degrading enzymes were screened and identified from T. chinensis seeds, which could provide theoretical basis for the study of the degradation mechanism of T. chinensis invasion into host cell wall and provide data support for the breeding of T. chinensis. [ABSTRACT FROM AUTHOR]

The inhibition rates of biocontrol fungus F2 on main pathogenic fungi of Panax notoginseng including Alternaria panax, Colletotrichum gloeosporioides and Fusarium solani were tested in this study. The effects of strain F2 on the mycelia growth of the 3 pathogenic fungi were also observed under the microscope. The results showed that strain F2 could inhibit A. panax, C. gloeosporioides and F. solani obviously with the high inhibition rates of 88. 67 %, 91. 00 % and 75. 76 % respectively. When observed under the microscope, mycelia growths of the 3 pathogenic fungi were affected obviously by strain F2. The mycelia of A. panax and C. gloeosporioides showed swollen, abnormal and cracked. And the mycelia of F. solani showed cracked. Base on the morphological and molecular biology characteristics analysis, strain F2 was identified as Trichoderma asperellum. [ABSTRACT FROM AUTHOR]

The anthracnose pathogen usually damages the leaves and stems of Sanguisorba officinalis L. in Guangxi, and reduces the quality and yield seriously. The pathogen was isolated and its pathogenicity was tested. The results showed that the pathogen was reisolated from all inoculated, symptomatic tissues. Furthermore，the pathogen was identified as Colletotrichum gloeosporioides based on the morphological characteristics, ITS DNA sequences analysis and reference books. [ABSTRACT FROM AUTHOR]