Hu Jinghan, Su Zhenhe, Dong Baozhu, Wang Dong, Liu Xiaomeng, Meng Huanwen, Guo Qinggang, Zhou Hongyou
College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010020, China.
Institute of Plant Protection, Hebei Academy of Agricultural and Forestry Sciences, Baoding 071000, China.
Curr Issues Mol Biol. 2023 May 26;45(6):4600-4611. doi: 10.3390/cimb45060292.
S-16 isolated from sunflower-rhizosphere soil is an effective biocontrol agent for preventing soilborne diseases in plants. Previous research revealed that the volatile organic compounds (VOCs) produced by the S-16 strain have strong inhibitory effects on . The identification of the VOCs of S-16 using gas chromatography-tandem mass spectrometry (GC-MS/MS) revealed 35 compounds. Technical-grade formulations of four of these compounds were chosen for further study: 2-pentadecanone, 6,10,14-trimethyl-2-octanone, 2-methyl benzothiazole (2-MBTH), and heptadecane. The major constituent, 2-MBTH, plays an important role in the antifungal activity of the VOCs of S-16 against the growth of . The purpose of this study was to determine the impact of the gene's deletion on the 2-MBTH production and to conduct an antimicrobial activity analysis of the S-16. The thiazole-biosynthesis gene was deleted via homologous recombination, after which the contents of 2-MBTH in the wild-type and mutant S-16 strains were analyzed using GC-MS. The antifungal effects of the VOCs were determined using a dual-culture technique. The morphological characteristics of the mycelia were examined via scanning-electron microscopy (SEM). Additionally, the lesion areas on the sunflower leaves with and without treatment with the VOCs from the wild-type and mutant strains were measured to explore the effects of the VOCs on the virulence of the . Moreover, the effects of the VOCs on the sclerotial production were assessed. We showed that the mutant strain produced less 2-MBTH. The ability of the VOCs produced by the mutant strain to inhibit the growth of the mycelia was also reduced. The SEM observation showed that the VOCs released by the mutant strain also caused more flaccid and gapped hyphae in the . The treated by the VOCs produced by the mutant strains caused more damage to the leaves than that treated by the VOCs produced by the wild type and the mutant-strain-produced VOCs inhibited sclerotia formation less. The production of 2-MBTH and its antimicrobial activities were adversely affected to varying degrees by the deletion of .
从向日葵根际土壤中分离出的S-16是一种有效的生物防治剂，可预防植物土传病害。先前的研究表明，S-16菌株产生的挥发性有机化合物（VOCs）具有很强的抑制作用。使用气相色谱-串联质谱法（GC-MS/MS）对S-16的VOCs进行鉴定，共鉴定出35种化合物。选择其中四种化合物的工业级制剂进行进一步研究：2-十五烷酮、6,10,14-三甲基-2-辛酮、2-甲基苯并噻唑（2-MBTH）和十七烷。主要成分2-MBTH在S-16的VOCs对其生长的抗真菌活性中起重要作用。本研究的目的是确定该基因缺失对2-MBTH产生的影响，并对S-16进行抗菌活性分析。通过同源重组缺失噻唑生物合成基因，然后使用GC-MS分析野生型和突变型S-16菌株中2-MBTH的含量。使用双培养技术测定VOCs的抗真菌作用。通过扫描电子显微镜（SEM）检查其菌丝体的形态特征。此外，测量了野生型和突变型菌株VOCs处理和未处理的向日葵叶片上的病斑面积，以探索VOCs对其毒力的影响。此外，评估了VOCs对菌核产生的影响。我们发现突变菌株产生的2-MBTH较少。突变菌株产生的VOCs抑制菌丝体生长的能力也降低了。SEM观察表明，突变菌株释放的VOCs也导致其菌丝体更加松弛和有间隙。突变菌株产生的VOCs处理的叶片比野生型产生的VOCs处理的叶片造成的损伤更大，并且突变菌株产生的VOCs对菌核形成的抑制作用更小。的缺失对2-MBTH的产生及其抗菌活性产生了不同程度的不利影响。
