辽宁省玉米茎腐病病原菌组成及优势种研究

On Pathogen Comoonents and Dominants of Corn Stalk Rot in Liaoning Province

１９９１～１９９４年从辽宁省玉米茎腐病主要发生区采集病株标样４９３株，自茎基１～２节和根部取病组织做常规分离，经单孢或单菌丝纯化后，进行病原菌种类鉴定和致病性测定．结果表明，Ｆｕｓａｒｉｕｍｇｒａｍｉｎｅａｒｕｍ和Ｐｙｔｈｉｕｍｓｐ．分离频率高，致病力强．Ｆ．ｍｏｎｉｌｉｆｏｒｍｅ和Ｆ．ｅｑｕｉｓｅｔｉ也具一定致病力，但分离频率较低．因此．认为Ｆ．ｇｒｕｍｉｎｅａｒｕｍ和Ｐｙｔｈｉｕｍｓｐ．是辽宁省玉米茎腐病的优势致病菌种类．

s: 493 samples from diseased plants were collected from heavily diseased areas in Liaoning province in 1991￣1994. Pathogens were obtained by conventional methods from 1￣2 nodes at stem base and root systems of diseased plants. Pathogens purified through selecting single spore of hypha were identified,and their pathogenicitiesWere assayed. Results showed that Fusarium graminearum and Pythum sp. were iaolatedmost frequently,and with the highest pathogenicities,whereas F. moniliforme and F. equiseti,to a cercain extent, had pathogenicity, but their isolation frequencies were lower. Itwas concluded that F. graminearum and Pythium sp. were dominant pathogens causingcorn stalk rot in Liaoning province.