蜡样芽孢杆菌NJSZ-13菌株诱导马尾松抗松材线虫病研究

【目的】蜡样芽孢杆菌NJSZ-13是1株能杀死松材线虫的松树内生细菌,研究该菌株能否诱导马尾松抗松材线虫病,为进一步开发利用该菌株抗松材线虫病提供理论依据。【方法】通过对2年生马尾松苗根部施用NJSZ-13菌株菌悬液和灭活的菌悬液后4 d再接种松材线虫,以观察不同处理的病情发展。测定该菌诱导处理后4天内和接种松材线虫AMA3虫株后28天内马尾松体内防御相关酶活性的变化。【结果】接种松材线虫后42 d,菌悬液和灭活菌悬液处理诱导马尾松抗松材线虫病的效果达54%和33%,且发病时间延迟。接种NJSZ-13菌株后,马尾松体内丙二醛(MDA)含量减少,过氧化氢酶(CAT)活性降低,而过氧化物酶(POD)、超氧化物歧化酶(SOD)、苯丙氨酸解氨酶(PAL)和多酚氧化酶(PPO)活性均显著高于对照;接种松材线虫后,菌悬液和灭活菌悬液处理的马尾松这5种酶活性明显高于未接种菌株的马尾松苗。总体上,菌悬液处理比灭活菌悬液处理的马尾松防御相关酶活性变化显著。【结论】蜡样芽孢杆菌NJSZ-13菌株能诱导马尾松抗松材线虫病,并且菌悬液的诱抗效果最佳。

A preliminary study on resistance of Pinus massoniana induced by Bacillus cereus NJSZ-13 strain to Bursaphelenchus xylophilus

【Objective】 Bacillus cereus NJSZ-13 strain is an endophytic bacterium in pine which can kill pine wood nematodes (Bursaphelenchus xylophilus). This study investigated whether this strain could induce the resistance of masson pine(Pinus massoniana) to pine wood nematodes which provides a theoretical basis for further development and utilization of this strain. 【Method】 The disease development of different treatments were observed and studied by inoculating with pine wood nematodes at four days after applying the bacterial suspension and inactivated bacterial suspension of NJSZ-13 strain on the roots of two years old masson pine seedlings. The changes of defense-related enzyme activities in masson pine were determined within 4 days after applying the bacteria and within 28 days after inoculating with pine wood nematode AMA3 strain.【Result】 The results showed that at 42 days after inoculated with pine wood nematodes, the effects of the bacterial suspension and inactivated bacterial suspension which induce the resistance of masson pine to pine wood nematode were 54% and 33%, and the disease occurrence time was delayed. After inoculation of NJSZ-13 strain, the content of MDA in the masson pine decreased, the activity of CAT decreased, and POD,SOD,PAL,PPO activities were significantly higher than those of the control. After inoculation with the pine wood nematode, the activity of the five enzymes of P. massoniana treated by the suspension and the inactivated suspension was significantly higher than that of the control, and the suspension showed higher changes in the index of massion pine than that of the inactivated suspension.【Conclusion】 Bacillus cereus NJSZ-13 strain could induce the resistance of masson pine to pine wood nematodes and the cell suspension is better.