【作者】 赵杏利；

【导师】 牛永春；

【作者基本信息】 中国农业科学院 ， 农业微生物， 2009， 硕士

【摘要】 于2007年至2008年杂草生长季节,从北京、河北、青海、河南、陕西、山西、吉林、辽宁8省市的农田、草坪和荒地采集了6种常见禾本科杂草狗尾草、马唐、牛筋草、虎尾草、稗草和画眉草的病害样品254份,分离获得病原真菌菌株434株,其中332株产生孢子。经形态学观察并结合其中183株典型菌株的rDNA ITS区域序列测定和分析结果,共鉴定到9属26种真菌:Alternaria alternata, A. astragali, A. citri, A. compacta, A. longipes, Bipolaris australiensis, B. maydis, B. peregianensis, B. sacchari, B. setariae, B. sorokiniana, Cladosporium cladosporioides, Colletotrichum gloeosporioides, Curvularia affinis, C. cymbopogonis, C. heteropogonicola, C. heterostrophus, C. lunata, Exserohilum monoceras, E. fusiforme, E. rostratum, Fusarium equiseti, F. incarnatum, F. proliferatum, Nigrospora oryzae, Phoma glomerata.。其中,链格孢属Alternaria和平脐孺孢属Bipolaris在6种杂草上均曾分离到,为优势属。国内有关于某一地区农田常见单子叶和双子叶杂草上的病原真菌调查、或针对一种杂草有潜在生防价值的病原真菌菌株筛选的报道,尚未见有专门进行较大地域范围内禾本科杂草上病原真菌资源的调查研究报道。本研究对我国北方八省市主要禾本科杂草上的病原真菌资源进行了较全面的调查和研究,初步探明了此类真菌资源的种类和分布,为进一步研究利用此类资源提供了资料和依据。在控制条件下,用人工接种方法对常见禾本科杂草和常见作物幼苗进行了部分菌株的致病性试验和寄主范围测定。对包括平脐孺孢菌、链格孢菌、弯孢菌和突脐孺孢菌在内的62个菌株接种了5种禾本科杂草,有11个菌株在不同植物上引起了程度不同的明显症状,其中7个菌株是在狗尾草上、2个菌株是在马唐上、1个菌株是在牛筋草上、1个菌株是在虎尾草上具有致病性。经对该11个菌株增加接种植物种类进行致病性重复试验,发现其中分离自河南南阳发病稗草的新月弯孢菌株ZXL07289a对虎尾草致病性强,而对供试其它杂草和作物只表现轻微致病性或不致病,表现一定的寄主专一性。分离自河南南阳发病狗尾草的狗尾草平脐孺孢菌株ZXL07290a表现出对狗尾草、虎尾草和马唐均有很强致病性,对谷子、高粱等禾本科单子叶作物也有显著致病性,但对大豆、棉花等双子叶作物不致病,寄主范围相对较广。初步试验表明,新月弯孢菌株ZXL07289a和狗尾草平脐孺孢菌株ZXL07290(aNY1)具有作为杂草生防菌株进一步开发成为微生物除草剂的潜力。致病性测定的62个菌株中有19株狗尾草平脐孺孢,结果表明,来自不同寄主植物的狗尾草平脐孺孢菌株对狗尾草的致病性存在明显差异,来自狗尾草的菌株比来自其它寄主植物的菌株对狗尾草致病性强,分离自野燕麦的菌株YS1对狗尾草无致病性,分离自不同地区不同狗尾草样品的菌株其致病性有显著差异。更多还原

【Abstract】 In growing seasons of 2007 and 2008, 254 samples were collected from diseased plants of 6 common gramineous weeds, including Setaria viridis, Digitaria sanguinalis, Eleusine indica, Chloris virgata, Echinochloa crusgalli, and Eragrostis cilianensis, growing in farmfield, lawn and wasteland in Beijing, Hebei, Qinghai, Henan, Shaanxi, Shanxi, Jilin and Liaoning. Four hundred and thirty-four strains of pathogenic fungi were isolated, out of which 332 strains produced spores.Based on morphological characteristics and sequence alignments of rDNA ITS region of 183 typic strains, 26 species of 9 genera were identified: Alternaria alternata, A. astragali, A. citri, A. compacta, A. longipes, Bipolaris australiensis, B. maydis, B. peregianensis, B. sacchari, B. setariae, B. sorokiniana, Cladosporium cladosporioides, Colletotrichum gloeosporioides, Curvularia affinis, C. cymbopogonis, C. heteropogonicola, C. heterostrophus, C. lunata, Exserohilum monoceras, E. fusiforme, E. rostratum, Fusarium equiseti, F. incarnatum, F. proliferatum, Nigrospora oryzae, Phoma glomerata. In which, Alternaria and Bipolari were isolated from all the 6 gramineous weeds and were dominant genera.There are some reports about pathogenic fungi on common monocotyledonous and dicotyledonous weeds in farm field in an area or screening of potential strains for biocontrol of a weed in China, but not any special report about pathogenic fungi on main Graminous weeds in a large geographical area. This research preliminarily proved up the kinds and distribution of the pathogenic fungi on the weeds Setaria viridis, Digitaria sanguinalis, Eleusine indica, Chloris virgata, Echinochloa crusgalli, and Eragrostis cilianensis in eight provinces in northern part of China, which provided resources and information for further research on and utilization of the fungal resources.Pathogenicity to the seedlings of common gramineous weeds and crops and host-range were tested for a part of strains with artificial inoculation under controlled conditions. Five gramineous weeds were inoculated with 62 strains, including species of the genera of Bipolaris, Alternaria, Curvularia, and Exserohilum. There were 11 strains that caused different notable symptoms, in which 7 strains had pathogenicity to S. viridis, 2 strains had pathogenicity to D. sanguinalis, 1 strain had pathogenicity to E. indica, 1 strain had pathogenicity to C. virgata. Pathogenicity tests were repeated for the 11 strains with some more kind of plants. We found that ZXL07289a, one strain of C. lunata from E. crusgalli in Nanyang of Henan province, had strong pathogenicity to C. virgata, but had no or little pathogenicity to other plants, and showed some specificity for host. The strain ZXL07290a of B. setariae from S. viridis in Nanyang of Henan provinc had strong pathogenicity to S. viridis, D. sanguinalis, and C. virgata, and notable pathogenicity to Sorghum vulgare and Setaria italic, but it had no or little pathogenicity to dicotyledonous crops such as soybean and cotton, and showed relatively wide host-range. Preliminary tests indicated that the strain ZXL07289a of C. lunata and the strain ZXL07290a of B. setariae had the potential to be developed as microbial herbicides. There were 19 B. setariae strains in the 62 strains tested for pathogenicicy, The results indicated that the strains from different hosts had different pathogenicity to S. viridis. The strains from S. viridis had stronger pathogenicity than those from other hosts to S. viridis. The strain from A. fatua had no pathogenicity to S. viridis. The pathogenicity of the strains from different geographical areas and different samples of S. viridis was notably different.更多还原