化学药剂胁迫下6株生防菌在黄瓜植株的定殖能力分析

郑丽; 黄杰豪; 刘红霞; 罗玉明; 郭坚华

doi:10.16768/j.issn.1004-874X.2022.02.015

化学药剂胁迫下6株生防菌在黄瓜植株的定殖能力分析

Analysis of Colonization Ability of Six Biocontrol Bacteria in Cucumber Plants under Chemical Stress Condition

摘要

摘要:
目的探究化学药剂胁迫对生防菌在黄瓜植株上定殖能力的影响。
方法设置一个温室试验和两个田间试验，分别在无药剂和无病原菌、无药剂和有病原菌、有药剂和有病原菌的黄瓜植株上处理生防菌。
结果供试的6株生防菌在黄瓜叶片和根围上均具有良好的定殖效果。在无药剂和无病原菌的温室条件下，各生防菌定殖量均呈现降-增-稳定的趋势，菌株1BS4和3BY4在黄瓜叶片和根围定殖能力较强，接菌后30 d定殖量接近10⁶ CFU/g(FW)，其余菌株定殖量保持在10⁴ CFU/g(FW)左右；在无药剂和有病原菌的田间条件下，各生防菌在叶片和根围的定殖量存在显著差异，且均呈现降-增-降-稳定的趋势，菌株5BJN1的定殖能力最强，接菌后30 d在黄瓜叶片和根围定殖量分别为10^5.92、10^4.95 CFU/g(FW)；在药剂和病原菌均存在的田间条件下，各生防菌在叶片和根围的定殖量存在差异，但差异不显著，也均呈现降-增-降-稳定的趋势，接菌后30 d菌株3BJN7和5BJN1在黄瓜叶片的定殖量较高，分别为10^3.88、10^4.23 CFU/g(FW)，其余菌株定殖量均在10³ CFU/g(FW)左右。
结论化学药剂对生防菌定殖能力的影响，取决于菌株类型，如3BJN7和5BJN1与药剂存在相容性；在黄瓜霜霉病菌存在时，使用化学药剂后它们仍可保持相当的定殖量；在无药剂胁迫时，霜霉病病原菌的出现能够诱导菌株3BJN7定殖能力的提升。

Abstract:
Objective The study was carried out to explore the effect of chemical stress on the colonization ability of biocontrol bacteria on cucumber plants.
Method By setting a greenhouse experiment and two field experiments, biocontrol bacteria were inoculated on cucumber plants without fungicides and pathogens, with fungicides and without pathogens, with fungicides and pathogens, respectively.
Result The six biocontrol strains tested had good colonization effects on cucumber leaves and roots. Under the greenhouse conditions without fungicides and pathogens, the colonization of each biocontrol strain showed a trend of decrease-increase-stability, strains 1BS4 and 3BY4 had strong colonization ability in cucumber leaves and roots. The colonization quantity of strains 1BS4 and 3BY4 was close to 10⁶ CFU/g(FW) at 30 days post inoculation(dpi) about 10⁴ CFU/g(FW); Under the field conditions without fungicides and with pathogens, there were significant differences in the colonization quantities of various biocontrol strains in leaves and roots, and they all showed a trend of decrease-increase-decrease-stability. Strain 5BJN1 had the strongest colonization ability. The colonization quantity of cucumber leaves and roots at 30 dpi was 10^5.92 CFU/g(FW) and 10^4.95 CFU/g(FW), respectively; Under the field conditions with both fungicides and pathogens, there were differences in the colonization quantity of biocontrol bacteria in leaves and roots, but the difference was not significant, and all showed a trend of decrease-increase-decrease-stability, and the colonization quantities of strains 3BJN7 and 5BJN1 in cucumber leaves at 30 dpi were relatively high, which were 10^3.88 CFU/g(FW) and 10^4.23 CFU/g(FW), respectively. The colonization quantity of other strains was about 10³ CFU/g(FW).
Conclusion The effect of chemicals on the colonization ability of biocontrol bacteria depends on the types of strains. Some strains (3BJN7 and 5BJN1) have good compatibility with chemicals. In the presence of cucumber downy mildew, they can still maintain a certain amount of colonization after using chemicals, therefore, they can be used as potential biocontrol agents; In the absence of fungicide stress, the emergence of downy mildew pathogen can induce the improvement of colonization ability of strain 3BJN7 so that it can colonize stably on cucumber plants.

HTML全文

参考文献(26)

施引文献

资源附件(0)