土槿皮乙酸对胶孢炭疽菌分生孢子萌发过程中核分裂的影响

Effect of pseudolaric acid B on nuclear behavior in process of spore germination of Colletotrichum gloeosporioides

为探究天然抑菌成分土槿皮乙酸对胶孢炭疽菌有丝分裂的影响,以多菌灵为药剂对照,以其亚致死剂量(EC30)处理了胶孢炭疽菌分生孢子,通过DAPI荧光染料染色观察了孢子萌发过程中的核相变化。结果表明,胶孢炭疽菌分生孢子在正常萌发过程的0~4 h,发生2次核分裂,之后菌体核分裂为1次/h,至12 h时共发生了10次核分裂;10 mg/L多菌灵处理胶孢炭疽菌12 h,菌体共发生了4次或5次核分裂,自第2次核分裂起,每次细胞核分裂的时间较未经药剂处理延迟5 h左右;5 mg/L土槿皮乙酸处理条件下,菌体12 h内共发生了7次核分裂,且自第3次核分裂后,每次核相发生变化的时间较未经药剂处理延迟3 h左右。可见,土槿皮乙酸能够抑制胶孢炭疽菌分生孢子萌发过程中细胞核的分裂,这可能与其抑制孢子萌发、芽管伸长及导致菌丝异常生长的作用有关。

Effect of natural fungicidal product,pseudolaric acid B,on nuclear division of Colletotrichum gloeosporioide was studied by DNA observation during dynamic change of nuclear behavior in spore germination,using DAPI fluorochrome as coloring agent after treatment by 30% inhibitory concentration of pseudolaric acid B with pesticide control of carbendazim.The results showed that spores of C. gloeosporioides divided two times during 0-4 h of normal germination, and they divided once an hour after germination for 4 h, and totally divided ten times during 12 h. Division times of nuclei were fouror five with treatment of 10 mg/L carbendazim for 12 h, and each division time was delayed about 5 h later than that without treatment since the second division. Division times of nuclei were seven with treatment of 5 mg/L pseudolaric acid B in 12 h, and nuclear behavior dynamic was delayed about 3 h since the third division. It indicated that pseudolaric acid B could inhibit cell nuclear division during spore germination of C. gloeosporioides, which may be related to spore germination inhabitation, germ tube elongation and abnormal growth of mycelial.