摘要
为科学评价球孢白僵菌BbFZ51菌株对松墨天牛幼虫的致病力,通过不同浓度白僵菌BbFZ01菌株孢悬液接种3龄松墨天牛幼虫,使用时间-剂量-死亡率模型(TDM模型)分析白僵菌侵染的剂量效应和时间效应.结果显示,供试各浓度(1.0×109、1.0×108、1.0×107、1.0×106、1.0×105孢子·mL-1)孢悬液处理后的天牛幼虫均逐渐发病死亡,但不同浓度处理的幼虫死亡速度存在显著差异,随着孢子浓度的升高,天牛幼虫的累计死亡率增速显著加快.1.0×109、1.0×108、1.0×107孢子·mL-1的累计死亡率分别在接种第7、8、9 d时达到100％;而1.0×106、1.0×105孢子·mL-1的致死速度相对较慢,在接种11 d后的累计死亡率分别为100％、97％.运用时间-剂量-死亡率模型对试验结果进行建模和分析,并利用该模型估算出球孢白僵菌BbFZ51菌株对松墨天牛天牛幼虫的致死剂量与致死时间;随着接种后时间延长,白僵菌对天牛幼虫的半数致死剂量(LD50)和90％致死剂量(LD90)逐渐降低,表明剂量效应逐渐增强,接种第4d、第5d、第6d、第7 d的半致死剂量对数值(LD50)分别为6.149、5.154、4.242、3.433;随着孢子浓度的升高,半数致死时间(LT50)和90％致死时间(LT90)显著缩短,表明时间效应逐渐增强,当孢子悬浮液浓度为1.0×107、1.0×108和1.0×109孢子·mL-1时,LT50分别为3.338 d、2.492 d、1.829 d,说明白僵菌BbFZ01菌株对松墨天牛幼虫具有较强的致病力,具有进一步作为其生防资源的潜力.
Abstract
To evaluate the pathogenicity of Beauveria bassiana strain BbFZ01 on the larvae of Monochamus alternatus,a time-dose-mortality model was used to analyze the dose and time effects of B.bassiana infection on the larvae of M.alternatus by inoculating them with spore suspensions of BbFZ01 at different concentrations.The test results showed that the larvae of M.alternatus treated with spore suspension at different concentrations(1.0×109,1.0×108,1.0×107,1.0×106,1.0×105 spores·mL-1)gradually became ill and died,but the death rate of larvae treated with different concentrations have significant discrepancy.Along with the increase of spore concentration,the cumulative mortality rate of M.alternatus larvae increased significantly.The cumulative mortality of 1.0×109,1.0×108 and 1.0×107 spores·mL-1 reached 100％on the 7th,8th and 9th day of inoculation respectively while the death rate of 1.0×106 and 1.0×105 spores·mL-1 was rela-tively slow,and their cumulative mortality after 11 days of inoculation was 100％and 97％respectively.The bioassay data was fitted the time-dose-mortality model,which successfully passed the Hosmer-Lemeshow fitting test,indicating its appropriateness for the given dataset,and the fitting effect was good,estimating the lethal dose and lethal time of B.bassiana to the larvae of the M.alternatus.With the extension of time after inoculation,the 50％lethal dose(LD50)and 90％lethal dose(LD90)of B.bassiana to M.alternatus larvae gradu-ally decreased,which indicated that the dose effect was gradually enhanced.The semi-lethal dose(LD50)on day 4,day 5,day 6 and day 7 were 6.149,5.154,4.242 and 3.433,respectively.The half lethal time(LT50)and 90％lethal time(LT90)decreased significantly with the increase of spore concentration,indicating that the time effect was gradually enhanced.When the spore concentration was 1.0×107,1.0× 108 and 1.0×109 spore·mL-1,The half lethal time(LT50)were 3.338 d,2.492 d and 1.829 d,respectively.In summary,the results showed that the strain BbFZ01 of B.bassiana has strong pathogenicity against the larvae of M.alternatus,and has the potential to be further used as a biocontrol resource.
基金项目
福建省属公益类科研院所专项(2022R1010004)
中央财政林业科技推广示范项目(闽[2022]TG11号)
维普
万方数据