烟草灰霉病侵染条件的研究

Study on infection regularity of tobacco gray mould

烟草灰霉病是黑龙江烟区新发现病害，个别地块已造成严重损失。自１９９０～１９９５年利用田间试验和控制条件接种方法，研究了烟草灰霉病病菌侵染来源和侵染规律，试验发现：①灰霉病菌Ｂｏｔｒｙｔｉｓｃｉｎｅｒｅａ侵染烟株的最适宜温度在１８℃左右，９℃以下或２７℃以上不能发生侵染，该菌发生侵染还必须满足９ｈ以上的湿润时间，１２～２４ｈ持续湿润利于侵染，光照对病菌侵染有抑制作用。②病菌的侵染来源主要是来自烟株病残体产生的分生孢子。③黑龙江烟区有两个侵染高峰，一个在６月中、下旬，另一个在８月中、下旬。这期间低温、多雨侵染率较高。

Tobacco gray mould(Botrytis cinerea Pers.)is a new disease which was found in 1989 in Heilongjiang tobacco field.It has made severe economic losses in some areas.Based on the results of inoculation experiments under the control condition and field examination from 1990 to 1995, the infection regularity and the pathogen source of tobacco gray mould are showed as followings(1)The most suitable temperature of infection for Botrytis cinerea on tobacco plant is around 18℃.The infection can not occur below 9℃ or above 27℃.Damp duration of more than 9hr is needed for the infection.(2)The pathogen source of inoculation is mainly from the conidiospore of infected tobacco plant residue the year before.(3)There are two infection peaks in Heilongjiang tobacco field:the mid late of June and the mid late of August.The disease was increased under low temperature and high precipitation in these periods.