摘要
【目的】研究对羟基苯甲酸对尖孢镰刀菌致病性的化感促进作用机制。【方法】采集三七道地产区云南省文山州种植地区不同种植年限的三七根系土壤,采用HPLC技术、宏基因组学技术,结合酶学研究方法,分析对羟基苯甲酸对尖孢镰刀菌的化感作用。【结果】未种植过三七的1年生、2年生、3年生土壤样品中对羟基苯含量不同,分别为3.48、3.95、2.22 mmol/L。自然生长状态下三七种植土壤中对羟基苯甲酸含量随着种植年限的延长而降低,同时伴随着土壤中的尖孢镰刀菌种群密度升高。当土壤中对羟基苯甲酸含量为2.61 mmol/L时,土壤中镰刀菌种群密度最高,为20.94%。随着对羟基苯甲酸含量的增加,土壤中镰刀菌种群密度下降,当其含量为5.11 mmol/L时,镰刀菌种群密度仅为1.057%。中等浓度的对羟基苯甲酸(2.5~5.0 mmol/L)促进尖孢镰刀菌生长,其菌落直径与对照相比升高,菌落颜色在培养24 h后呈现紫色,菌丝生长较对照稍绵密,显微镜下可观察到大量分生小孢子的生成;促进了尖孢镰刀菌果胶酶的活性,其中浓度为2.5 mmol/L时,果胶酶活力为1.02 U/(mL·min);在2.5~10.0 mmol/L浓度的对羟基苯甲酸胁迫下,纤维素酶活力变化不大。【结论】对羟基苯甲酸化感促进尖孢镰刀菌的最佳浓度为2.0~3.0 mmol/L。该浓度下土壤中尖孢镰刀菌种群密度最高,菌落直径、孢子产量达到最高值,且对致病性酶分泌具有促进作用。
【Objective】The present study aimed to investigate the mechanism of allelopathy-promoting action of p-hydroxybenzoic acid on the pathogenicity of Fusarium oxysporum.【Method】In the study,the root soil of Panax notoginseng with different planting years in the genuine producing area of Wenshan prefecture,Yunnan province was collected.The allelopathic effect of p-hydroxybenzoic acid on F.oxysporum was analyzed using HPLC,metagenomics combined with enzymology.【Result】The soil planted P.notoginseng for 1,2 and 3 years had varied p-hydroxybenzene acid contents,which were 3.48,3.95 and 2.22 mmol/L,respectively.Under natural growth state,content of p-hydroxybenzoic acid in P.notoginseng planting soil decreased with planting time,while the population density of F.oxysporum increased.When the content of p-hydroxybenzoic acid in the soil was 2.61 mmol/L,the population density of F.oxysporum was only 20.94%.With the increase of p-hydroxybenzoic acid content,the population density of F.oxysporum in the soil decreased.When p-hydroxybenzoic acid content was 5.11 mmol/L,the density of F.oxysporum was only 1.057%.The medium concentration of p-hydroxybenzoic acid(2.5-5.0 mmol/L)promoted the growth of F.oxysporum,and its colony diameter was higher than that of the control.The colony was purple after 24 hours of culture,and the mycelial growth was slightly denser than that of the control.Moreover,a large number of conidia could be observed under the microscope,the activity of pectinase of F.oxysporum was promoted,which was 1.02 U/(mL·min)when the concentration was 2.5 mmol/L.Under stress of 2.5-10.0 mmol/L p-hydroxybenzoic acid,the cellulase activity changed little.【Conclusion】The optimal p-hydroxybenzoic acid concentration for promoting the allelopathy of F.oxysporum was about 2.0-3.0 mmol/L.At this concentration,the population density of F.oxysporum in soil was the highest,the colony diameter and spore yield reached the peak,and the secretion of pathogenic enzymes was promoted.
作者
赵静
万琼莲
焦蓉
王占娣
王连春
ZHAO Jing;WAN Qiong-lian;JIAO Rong;WAN Zhan-di;WANG Lian-chun(College of Chemistry Biology and Environment,Yuxi Normal University,Hongta,Yunnan 653100,China)
出处
《西南农业学报》
CSCD
北大核心
2023年第1期112-117,共6页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金项目(32060036)。
