三株球孢白僵菌对栗实象甲幼虫的感染和致病力研究

发布时间：2018-10-25 14:16

【摘要】：为了明确球孢白僵菌Beauveria bassiana 3菌株TST05、FDB01、SYN01对栗实象甲老熟幼虫的感染、致死率、致死中时、以及胞外蛋白酶、几丁质酶、脂肪酶的活性与毒力的关系,本研究采用3个菌株的孢子悬浮液(1.0×108孢子/m L),浸虫法感染栗实象甲幼虫,统计连续8 d的校正死亡率;以栗实象甲幼虫的虫体作为菌株的唯一碳源制备液体培养基,测定培养过程中各菌株的脂肪酶、几丁质酶、类枯草杆菌蛋白酶(Pr1酶)连续8 d的酶活性变化。结果表明,球孢白僵菌3个菌株TST05、FDB01、SYN01感染栗实象甲幼虫后,1-4 d内表现出染病和死亡的症状,连续8 d累积校正死亡率分别为40%、44.4%、62.22%,菌株SYN01对栗实象甲的致死率最高,与其他两菌株的差异显著;菌株TST05、FDB01、SYN01的Pr1酶活性最大峰值分别为(175.56±0.7)U/m L、(172.74±2.32)U/m L、(195.71±5.41)U/m L。几丁质酶活性最大峰值分别为(12.58±0.58)U/m L、(13.06±1.16)U/m L、(15.12±0.32)U/m L。都是菌株SYN01的酶活性最大,而TST05和FDB01之间差异不显著;球孢白僵菌3个菌株的Pr1酶、几丁质酶、脂肪酶在8 d内的酶活性平均值与染菌幼虫8 d累积校正死亡率的线性回归方程分别为y=0.4641x+122.45(R2=0.8854)、y=0.034x+10.473(R2=0.9328)、y=0.0354x+2.4586(R2=0.1201),说明菌株的Pr1酶和几丁质酶活性与幼虫死亡率之间呈显著的线性相关,而菌株的脂肪酶活性与菌株对幼虫的致死率不具有线性关系。综合分析,菌株SYN01可以作为生物防治栗实象甲的病原菌种;Pr1酶与几丁质酶的活性可作为菌株的毒力因子。
[Abstract]:In order to clarify the relationship between the infection, mortality, death rate, the activity of extracellular protease, chitinase, lipase and virulence of Beauveria bassiana 3 strain of Beauveria bassiana on mature larvae of chestnut. In this study, the sporozoite suspension (1.0 脳 108spore / m L), dipping method) of three strains was used to infect chestnut larvae, and the corrected mortality of chestnut larvae was calculated for 8 days, and the liquid medium was prepared by using the larvae of chestnut larvae as the sole carbon source of the strains. Lipase, chitinase and Pr1 enzyme activity of each strain were determined for 8 days. The results showed that three strains of Beauveria bassiana (TST05,FDB01,SYN01) showed symptoms of infection and death within 1-4 days after infection with C. bassiana larvae. The cumulative corrected mortality for 8 days was 400.44.4% and 62.22%, respectively. Strain SYN01 had the highest mortality to chestnut weevil. The peak value of Pr1 enzyme activity in TST05,FDB01,SYN01 was (175.56 卤0.70) U / -mL, (172.74 卤2.32) U / -mL, (195.71 卤5.41) UP / mL, respectively. The peak value of chitinase activity was (12.58 卤0.58) U / mL, (13.06 卤1.16) U / mL, (15.12 卤0.32) U / mL, respectively. The enzyme activity of SYN01 was the largest, but there was no significant difference between TST05 and FDB01. The Pr1 enzyme, chitinase of three strains of Beauveria bassiana, The linear regression equations of lipase activity in 8 days and the cumulative corrected mortality rate in 8 days of inoculated larvae were yx0.4641x 122.45 (R2O0.8854), YC0.034x 10.473 (R20.9328), YC0.0354x 2.4586 (R2C0.1201), indicating that there was a significant linear correlation between the activity of Pr1 enzyme and chitinase activity and larval mortality. However, there was no linear relationship between lipase activity and larval mortality. Comprehensive analysis showed that strain SYN01 could be used as pathogen of chestnut weevil, and the activity of Pr1 and chitinase could be used as virulence factor of chestnut.
【作者单位】：山西大学生命科学学院;
【基金】：山西省科技攻关项目(20140311017-6)
【分类号】：S436.64;S476.12

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