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[Objective] The present paper aimed to investigate the effect of biocontrol agents with dazomet on soil microbial community structure and basic physicochemical properties in order to pave a way for good management in Panax notoginseng cultivation. [Method] A randomized group experiment was designed with edaphic condition (fumigation) and treatment (biocontrol agents) as the two treatment factors. The basic physicochemical properties of the soil were detected and the effect of different treatment factors on the structure of the soil microbial community was analyzed using high throughput sequencing techniques to determine the association between the main physicochemical properties of the soil and the bacterial community. [Result] Soil fumigation increased the abundance of the Proteobacteria, Actinobacteriota and Bacteroidota in the bacterial community, at the same time reduced the abundance of the Gemmatimonadota and Acidobacteriota. The Ascomycota and Basidiomycota were the dominant fungal phylum with the highest abundance in all treatment groups. The soil pH after fumigation significantly decreased compared to that of non-fumigated soil. The bacterial alpha diversity index increased more significantly in the non-fumigated soil added biocontrol agents group, whereas the addition of biofungicide after fumigation reduced fungal alpha diversity. The pH and available nitrogen levels were significantly lower in fumigated sites than in non-fumigated sites under the same treatments, while the addition of biofumigants reduced soil available phosphorus and potassium under the same soil conditions. The pH and available nitrogen levels were significantly lower in fumigated sites than in non-fumigated sites under the same treatments, while the addition of biofumigants reduced soil available phosphorus and potassium under the same soil conditions. Available nitrogen and pH contributed to the strongest correlation with microbial community structure. The addition of biocontrol agents effectively reduced the abundance of Fusarium, Cylindrocarpon, Altemaria and Plectosphaerella and increased the abundance of beneficial genera such as Pseudomonas, Lysobacter and Burkholderia. The addition of biocontrol agents under the same soil conditions significantly reduced the abundance of Moritierella, Fuarium, Aspergillus, Penicillium, Cladosporium which were dominant genera in the fumigated sites. [Conclusion] Non-fumigated land applying biocontrol agents could improve soil acidification during P. notoginseng cultivation. The effect of the biocontrol agents on the alteration of microbial diversity was inconsistent under different soil conditions. Overall, the application of biocontrol agents could improve the microbial community structure of the soil in P. notoginseng cultivation sites and provide an effective method for the prevention and control of P. notoginseng root rot. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of lidamycin on the proliferation of human cervical cancer Caski cells and its underlying molecular mechanisms. Methods Human cervical cancer Caski cells were randomly divided the experimental groups (including the low-dose, medium-dose and high-dose groups) which were separately treated with 1 , 2.5 and 5 ng/mL lidamycin ( 100 μL) for 24 h, and the control group which was added with the same volume of RPM1-1640. MTT assay was used to detect the inhibition rate of proliferation. The cell cycle and mitochondrial membrane potential of CasKi cells were measured by flow cytometry. Transmission electronic microscope was used to observe the morphological changes of Caski cells. We calculated tlie apoptosis rate and mitotic catastrophe rate. Results The proliferation rate and survival rate of the experimental groups were significantly lower than those of the control group, and the decrease in the high-dose group was more significant ( all P <0. 05 ). flic percentage of cells in the S phase ol the control group and the medium-dose group was higher than those in the low-dose and high-dose groups (all P <0.05). The percentage of cells in the G0/G1 phase of the experimental groups was lower than that of the control group and the percentage of cells in the G2/M phase was higher than that of the control group, especially in the medium-dose and high-dose groups ( all P <0. 05). The ratios of mitochondrial membrane potential decrease in the low-dose, medium-dose and high-dose groups and control group were 34.77% ±5.33% , 37.87% ±5.73% , 18.37% ±3.91% , and 4. 17% ±0.65% , respectively. The mitochondrial membrane potential decreased ratios of the experimental groups were higher than that in the control group, especially in the low-dose and medium-dose groups (all P <0.05). Transmission electronic microscopy showed that the control group had normal morphology while the experimental groups had many forms of death cells, including apoptosis, necrosis and mitotic catastrophe. The apoptosis rate and mitotic catastrophe rate of the experimental groups were both higher than those of control group (both P <0.05). Conclusion Lidamvcin can significantly inhibit the proliferation of Caski cells with an dose-de-pendent manner by inducing the apoptosis and mitotic catastrophe of cells. [ABSTRACT FROM AUTHOR]