【摘要】 用松针褐斑病菌毒素粗提液处理湿地松、火炬松、黑松和马尾松的切根苗，发现湿地松和火炬松对毒素最为敏感，其次为马尾松，黑松最不敏感。毒素生测的结果与松树在田间自然感染的情况有一定的相似性，但不完全一致。不同湿地松抗病无性系对毒素的反应存在着差别，其中３３ 号所受伤害较轻，１０ 号及３６ 号较重。结合毒素薄层层析半定量试验，利用寄主愈伤组织对毒素的反应，发现毒素对寄主愈伤组织的最低作用浓度应在１００ μｇ／ｍ Ｌ 以下。试验了５ 种杂草对毒素的反应，其中空心莲子草和稞草对毒素敏感。进一步研究利用毒素作为除草剂不失为毒素利用的一个新思路。上述研究表明该毒素为非寄主专化性毒素。更多还原

【Abstract】 The root cutted seedlings of several pine species were treated with the toxin of brown spot needle blight fungus( Lecanosticta acicola), and the results showed that slash pine (Pinus elliottii Engelm.)and lobollolly pine( P.taeda L.)were very sensitive,masson pine ( P.massoniana Lamb.)was also sensitive,but japanese black pine( P.thunbergii Parl.)was not so sensitive.The results of toxin bioassay were simillar with the expression of natural infection in the field,but not totally identical.There were some differences in the reaction of slash pine resistant clones to the fungus toxin.The minimal effective concentration of the toxin was less than 100 μg/mL.The toxin was also virulent to Alternanthera philixeroides and Echinochloa crusgalli. The results suggested as though the toxin should be a kind of non host specific toxin(NHST),it actually possessed some biological specialization.更多还原