摘要
５个栽培品种的盆栽植株，于１３片真叶展开时人工接种，比较各叶位叶片的感病性。结果表明：烟叶自下而上逐渐成熟衰老，随着叶色由绿转黄，叶绿素含量依次递减，其汁液可溶性糖及浸出液还原糖含量递增，感病性相应地提高。以叶色为指标，绿色叶片对病害免疫；轻微转黄的绿叶，高度抗病，只能形成褐色小点，而不能产生分生孢子，也不能再扩展；中度转黄的绿叶上形成０．２ｃｍ以下的小斑，也不产生孢子，多数不能再扩展；黄色叶片为高感型，能形成０．５ｃｍ以上的典型病斑，并产生大量孢子。以１％葡萄糖液为介质，孢子萌发率以接种烟株的病情指数高于１％蔗糖液。以黄叶液为孢子液介质，其发芽率及接种发病率均高于黄绿叶及绿叶汁液。这说明烟叶成熟衰老程度与感病性高度相关。
The results of inoculating 1-7 lower leaves of tobacco pot plants of five cultivars showed:as leaves became mature or senescent from bottom upward to top of tobacco plant,their color was changed from green to yellow,the chlorophyll content was decreased,dissolvable sugar content of leaf sap and reducing sugar of diffused leaf sap were increased,but the disease resistance was decreased correspondingly.If leaf color was used as creterion of resistance,green growing leaf was immune;rather yellowish green leaf was highly resistance,only pin tip size brown specks were formed which could neither expand nor sporulate;greenish yellow leaf was moderately susceptible,spots about 0.2 cm in diameter could be formed on it,and most of them could no enlarge any more under general climate condition;mature yellow leaf was high.Susceptible,on which typical spots larger than 0.5 cm in diameter were always formed and sporulated profusely.Spore germination rate and disease index after inoculation with medium of 1% glucose were higher than with medium of 1% sucrose.Spore germination rate and disease. incidence after inoculation with medium of mature tobacco leaf were also higher than medium with yellowish green and green tobacco leaves.The results indicated that maturity of tobacco leaf was highly correlated with the resisatance to brown spot disease.
出处
《植物病理学报》
CAS
CSCD
北大核心
1998年第1期49-54,共6页
Acta Phytopathologica Sinica
基金
黑龙江省科委攻关课题
关键词
烟草
赤星病
成熟衰老程度
感病性
Tobacco brown spot Maturity or senescence Susceptibility Alternaria alternata
