| In Shanghai, the strawberry area expanded rapidly in recent years, and anthracnose disease on strawberry occurred more and more severely. It is becoming the third most serious disease in exception to gray mould and powdery mildew on strawberry.Strawberry anthracnose samples were collected from Shanghai surburbs and seventeen isolates were obtained. All of them could cause disease to strawberry after inoculation, they also could be recovered from the inoculated strawberry, so it accorded with Koch's postulates, and all them were the pathogens of strawberry anthracnose.Through the comparison of conidia morphology, observation of teleomorph and analysis of rDNA ITS similarity, 16 isolates were identified as Colletotrichum gloeosporioides,taking up about 94% of the total,and only one isolate was identified as Colletotrichum acutatum. The isolates of C. gloeosporioides formed caesious, gray, greyblack and fluffy colonies and their conidia were hyaline, one- celled, ovoid to oblong,about 13.0～19.7×4.1～7.3μm in size, and 15.2～17.4×5.1～5.8μm in average, 11 strains easily produced teleoform on PSA. The colony of C. acutatum in culture was orange and cottony,and its conidia were one-celled, hyaline, and fusiform,about 12.1～16.4×3.6～5.4μm in size,and 14.3×4.5μm in average, no telemorph was observed on PSA.Biological characteristics of above two Colletotrichum species were studied. Light has great effect on mycelial growth and spore germination of the pathogens. QPg-961 formed colonies of 69.5, 66.5, 60.5 mm in diameter, and produced 1.0×10~6, 2.5×10~6, 1.8×10~7 spores/petri dish on PSA respectively under successive light (3000 lx), 12h light and 12 darkness, successive darkness for 6 days. However, CMf-04 formed 41.5, 40.3 and 31.2 mm in diameter and produced 2.8×10~7, 6.8×10~7 and 7.3×10~7 spores/petri dish under the same condition as above for 6 days. At the initial stage, darkness was more suitable for spore germination of both QPg-961 and CMf-04.QPg-961 could grow at 10~℃to 36℃and fastest at 28℃on PSA. It easily produced conidia at 20℃to 28℃, and highest at 26℃; while it was difficult to form at 16℃below or 30℃above. Its conidia could easily germinate at 12℃to 34℃. There was little effect of pH on mycelial growth of QPg-961, and pH 5 was optimum for the mycelial growth. It could produce more conidia under condition of weak acid (pH 5～6) and was inhibited to form conidia under alkaline condition. Among all of the seven kinds of carbon sources, glucose, sucrose, maltose and D-fructose were better for mycelial growth, and maltose was best for the conidial generation; Among all of the seven kinds of nitrogen sources, tryptone was best for mycelial growth, and yeast extract, tryptone and beef extract were best for conidial generation.CMf-04 could grow at 10~℃～32℃, and quickest at 24℃. It easily generated conidia at 24℃～30℃, and highest at 26℃; while it was difficult to form conidia at 20℃below or 32℃above. The conidia germinated well at 12℃～32℃, and fail to germinate at 10~℃below or 34℃above. The pH affected its mycelial growth little, and pH 5 was optimum for mycelial growth. It could generate more conidia at pH 8～10~ and few under acidic condition. Among all of the seven kinds of carbon sources, glucose, sucrose, maltose and D-fructose were better for mycelial growth; D-fructose was best for the conidial generation;Among all of the seven kinds of nitrogen sources,yeast extract, tryptone and beef extract were better for the mycelial growth and conidial generation.The inhibition of various fungicides to mycelial growth of pathogens was conducted in vitro. Results indicated that Score and Tilt were best to QPg-961 among all of seven fungicides with EC50 of 0.024μg/mL and 0.19μg/mL respectively; Dacotech and Bromothalonil were good with EC50 of 36.45μg/mL and 14.85μg/mL respectively; Carbendazim, Mancozeb and Amister were poor with EC50 of 1229.99μg/mL, 213.16μg/mL and 169.79μg/mL respectively. The virulent degrees of all fungicides to QPg-961 were as follows:Score > propiconazole > Bromothalonil > Dacotech > Amistar > Mancozeb > Carbendazim.Score,Carbendazim and Tilt were better to CMf-04 among all of the seven fungicides with EC50 of 0.021μg/mL, 0.53μg/mL and 0.22μg/mL respectively; and Amister and Bromothalonil were good with EC50 of 3.31μg/mL, 23.38μg/mL respectively, Dacotech and Mancozeb were poor with EC50 of 138.68μg/mL and 1258.93μg/mL repectively. The virulence degrees of all fungicides to CMf-04 were as follows:Score > Tilt > Carbendazim > Amistar > Bromothalonil > Dacotech > Mancozeb.It was proved that the main pathogen of strawberry anthracnose occurring at seedling stage in summer in Shanghai suburbs was C. gloeosporioides. C. acutatum, a kind of another anthraonose pathogen was found in Shanghai, which was first reported in China. Studies on biological characteristics and virenlence test of various fungcides made clear that there was a great difference between two pathogens above. It also provides much academic support for control of strawberry anthrocnose and resistence breeding in Shanghai and other areas.
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