摘要
分别用强、弱致病力松材线虫虫株和无致病力拟松材线虫虫株接种2年生黑松,观测接种后不同时间段黑松茎段水势和根系活力变化情况。结果表明:接种强、弱致病性松材线虫虫株后,在未表现出明显症状时,黑松水势都有一个降低然后回升的过程,但当树体内线虫开始大量繁殖、外部表现萎蔫症状时,黑松水势发生不可逆转的急速降低,松树死亡,强致病性松材线虫虫株比弱致病性松材线虫虫株导致黑松茎水势丧失速度快。接种无致病力拟松材线虫后,开始黑松水势下降,然后缓慢回升接近正常水势,随着线虫的死亡,树体水势恢复正常。接种3种线虫虫株后,黑松根系活力随着线虫的侵入都有一个升高的过程,接种强、弱致病力松材线虫虫株后,黑松出现萎蔫时,根系活力虽然有所下降,但仍然保持较好的根系活力,直到松树干枯后根系活力才丧失,这与干旱胁迫下,植物首先丧失根系活力然后表现萎蔫不同;接种无致病力拟松材线虫后,随着拟松材线虫在黑松体内的死亡,黑松的根系活力在升高后逐渐恢复正常。
Two Bursaphelenchus xylophilus isolates （virulent and avirulent） and one B. mucronatus isolate were inocula- ted separately on biennial seedlings of Pinus thunbergii. Changes in water stress and activity of roots system at different periods after inoculation were measured. The results showed that at the beginning period, the seedlings were inoculated with isolates （virulent and avirulent） and the obvious symptoms had not appeared yet, the water stress of P. thunbergii experienced a process of lowering and being back up again. But when B. xylophilus inside the seedlings began propaga- ting in large quantities and the outer was in a wilting state, the water stress of P. thunbergii lowered at a high speed irre- versibly and P. thunbergii died very soon. Compared with avirulent B. xylophilus isolate, virulent B. xylophilus isolate caused P. thunbergii to lose water much faster. After B. mucronatus isolate was inoculated, the water stress of seedlings of P. thunbergii lowered and then rose again and approached to the normal level. Along with the death of B. xylophilus, the water stress of seedlings returned to the normal state. With the invasion of B. xylophilus, the activity of roots system of P. thunbergii had a rising process. At the beginning period inoculated with B. xylophilus isolates （ virulent and aviru- lent） , though the activity of P. thunbergii had decreased somewhat, still maintained a good activity of roots system and the activity would not lose until the trunk dried out, which was different from the phenomenon that the activity of roots system was gradually lost and the plant showed the symptom of wilting caused by drought. Inoculated with B. mucronatus isolate and with the death of B. xylophilus, the activity of P. thunbergii returned to the normal state after a rising trend.
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2009年第6期53-56,共4页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
国家自然科学基金资助项目(30471392)
教育部博士学科点基金资助项目(20040298010)
关键词
松材线虫
拟松材线虫
黑松
水势
根系活力
Bursaphelenchus xylophilus
B. mucronatus
Pinus thunbergii
water potential
root activity
