The susceptibility of different regions in Dioscorea rotundata (white yam) tuber to rot infecting fungi was investigated. Isolation was made from the periphery of the rotted tuber tissues, followed by a pathogenicity ...The susceptibility of different regions in Dioscorea rotundata (white yam) tuber to rot infecting fungi was investigated. Isolation was made from the periphery of the rotted tuber tissues, followed by a pathogenicity test and identification of isolates. Three fungi associated with D. rotundata (white yam) were isolated;they include Penicillium oxalicum, Aspergillus niger and Rhizopus stolonifer. Each of the isolates from pure cultures were inoculated on the head, middle and tail regions of healthy yam tubers. The three fungi were found to be pathogenic at different rates at the head, middle and tail ends of the yam tuber respectively. The head region was less susceptible to the three fungi with the following rot depths (P. oxalicum 25 mma, A. niger 18.2 mma and R. stolenifer 12.7 mmb). Rot depth in the middle region was (P. oxalicum 15 mma, A. niger 10.6 mma and R. stolenifer 8.8 mmb). While the tail region of the yam tuber recorded rot depth of (P. oxalicum 32.0 mma, A. niger 26.4 mma and R. stolenifer 20.8 mmb) respectively. Generally, the tail region of D. rotundata was more susceptible to fungal attack and the rot recorded in the tail region was significantly different from rot at the middle and the head. It was recommended that yam tubers should be stacked with their head on the ground to reduce incidence of rotting in stock-piled yam tubers.展开更多
小麦茎基腐病(crown rot,CR)和赤霉病(Fusarium head blight,FHB)是由镰孢菌引起的两种主要的小麦病害。为筛选对CR和FHB的优异抗源、发掘抗病基因,从1000多个来自世界各地的小麦种质中筛选了311个核心种质,对其进行CR苗期和成株期抗性...小麦茎基腐病(crown rot,CR)和赤霉病(Fusarium head blight,FHB)是由镰孢菌引起的两种主要的小麦病害。为筛选对CR和FHB的优异抗源、发掘抗病基因,从1000多个来自世界各地的小麦种质中筛选了311个核心种质,对其进行CR苗期和成株期抗性及FHB抗性鉴定和评价,并利用全基因组关联分析(GWAS)鉴定与CR和FHB抗性相关位点。结果筛选出4个种质(Cimrmanova、济南13、GHABAGHEB、秃芒麦)具有优良的CR抗性;12个种质(陇春8号、中麦175、鲁麦5号、潍麦6号、皖麦50、Reeves、石家庄8号、西农928、山麦、SAFI-1/ZEMAMRA-1、平阳181和石家庄54)具有优良的FHB抗性;5个种质(山前麦、陇春8号、内江31、聊麦16和淮麦22)对CR和FHB均表现一定的抗性,尤其是陇春8号对CR成株抗性和FHB抗性水平均达到R级,表明该种质对两种病害兼具优良抗性。通过GWAS分析发现,在1A和6B染色体上有6个SNPS与CR-SR抗性显著相关;在1A、1B、3A、3B、6A、6B和6D染色体上有15个SNPS与CR-APR抗性显著相关;在5A、7A和7B染色体上有13个SNPS与FHB抗性显著相关。本研究结果为小麦抗CR和FHB基因的定位和育种奠定了基础。展开更多
文摘The susceptibility of different regions in Dioscorea rotundata (white yam) tuber to rot infecting fungi was investigated. Isolation was made from the periphery of the rotted tuber tissues, followed by a pathogenicity test and identification of isolates. Three fungi associated with D. rotundata (white yam) were isolated;they include Penicillium oxalicum, Aspergillus niger and Rhizopus stolonifer. Each of the isolates from pure cultures were inoculated on the head, middle and tail regions of healthy yam tubers. The three fungi were found to be pathogenic at different rates at the head, middle and tail ends of the yam tuber respectively. The head region was less susceptible to the three fungi with the following rot depths (P. oxalicum 25 mma, A. niger 18.2 mma and R. stolenifer 12.7 mmb). Rot depth in the middle region was (P. oxalicum 15 mma, A. niger 10.6 mma and R. stolenifer 8.8 mmb). While the tail region of the yam tuber recorded rot depth of (P. oxalicum 32.0 mma, A. niger 26.4 mma and R. stolenifer 20.8 mmb) respectively. Generally, the tail region of D. rotundata was more susceptible to fungal attack and the rot recorded in the tail region was significantly different from rot at the middle and the head. It was recommended that yam tubers should be stacked with their head on the ground to reduce incidence of rotting in stock-piled yam tubers.
文摘小麦茎基腐病(crown rot,CR)和赤霉病(Fusarium head blight,FHB)是由镰孢菌引起的两种主要的小麦病害。为筛选对CR和FHB的优异抗源、发掘抗病基因,从1000多个来自世界各地的小麦种质中筛选了311个核心种质,对其进行CR苗期和成株期抗性及FHB抗性鉴定和评价,并利用全基因组关联分析(GWAS)鉴定与CR和FHB抗性相关位点。结果筛选出4个种质(Cimrmanova、济南13、GHABAGHEB、秃芒麦)具有优良的CR抗性;12个种质(陇春8号、中麦175、鲁麦5号、潍麦6号、皖麦50、Reeves、石家庄8号、西农928、山麦、SAFI-1/ZEMAMRA-1、平阳181和石家庄54)具有优良的FHB抗性;5个种质(山前麦、陇春8号、内江31、聊麦16和淮麦22)对CR和FHB均表现一定的抗性,尤其是陇春8号对CR成株抗性和FHB抗性水平均达到R级,表明该种质对两种病害兼具优良抗性。通过GWAS分析发现,在1A和6B染色体上有6个SNPS与CR-SR抗性显著相关;在1A、1B、3A、3B、6A、6B和6D染色体上有15个SNPS与CR-APR抗性显著相关;在5A、7A和7B染色体上有13个SNPS与FHB抗性显著相关。本研究结果为小麦抗CR和FHB基因的定位和育种奠定了基础。
