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Microorganisms Apr 2024In the continuous cropping of , the pathogenic fungi in the rhizosphere soil increased and infected the roots of , resulting in a decrease in yield. This is an urgent...
In the continuous cropping of , the pathogenic fungi in the rhizosphere soil increased and infected the roots of , resulting in a decrease in yield. This is an urgent problem that needs to be solved in order to effectively overcome the obstacles associated with the continuous cropping of . Previous studies have shown that inhibits pathogenic fungi in the rhizosphere of , but the inhibitory effect was not stable. Therefore, we hope to introduce biochar to help colonize in soil. In the experiment, fields planted with for 5 years were renovated, and biochar was mixed in at the same time. The applied amount of biochar was set to four levels (B0, 10 kg·hm; B1, 80 kg·hm; B2, 110 kg·hm; B3, 140 kg·hm), and biological agent was set to three levels (C1, 10 kg·hm; C2, 15 kg·hm; C3, 25 kg·hm). The full combination experiment and a blank control group (CK) were used. The experimental results show that the overall decreased by 0.86%~65.68% at the phylum level. increased by -73.81%~138.47%, and increased by -51.27%~403.20%. At the genus level, increased by -10.29%~855.44%, decreased by 35.02%~86.79%, and increased by -93.60%~680.62%. mainly causes acute bacterial wilt root rot, while mainly causes yellow rot. Under different treatments, the Shannon index increased by -6.77%~62.18%, the Chao1 index increased by -12.07%~95.77%, the Simpson index increased by -7.31%~14.98%, and the ACE index increased by -11.75%~96.12%. The good_coverage indices were all above 0.99. The results of a random forest analysis indicated that , , and were the top three most important species in the soil, with MeanDecreaseGini values of 2.70, 2.50, and 2.45, respectively. , the primary pathogen of , ranked fifth, and its MeanDecreaseGini value was 2.28. The experimental results showed that the B2C2 treatment had the best inhibitory effect on , and the relative abundance of in rhizosphere soil decreased by 86.79% under B2C2 treatment; the B1C2 treatment had the best inhibitory effect on , and the relative abundance of in the rhizosphere soil decreased by 93.60% under B1C2 treatment. Therefore, if we want to improve the soil with acute Ralstonia solanacearum root rot, we should use the B2C2 treatment to improve the soil environment; if we want to improve the soil with yellow rot disease, we should use the B1C2 treatment to improve the soil environment.
PubMed: 38674727
DOI: 10.3390/microorganisms12040783 -
International Journal of Molecular... Aug 2023Rhizosphere microbial communities can influence plant growth and development. Natural regeneration processes take place in the tree stands of protected areas, which...
Rhizosphere microbial communities can influence plant growth and development. Natural regeneration processes take place in the tree stands of protected areas, which makes it possible to observe the natural changes taking place in the rhizosphere along with the development of the plants. This study aimed to determine the diversity (taxonomic and functional) of the rhizosphere fungal communities of Norway spruce growing in one of four developmental stages. Our research was based on the ITS region using Illumina system sequencing. Saprotrophs dominated in the studied rhizospheres, but their percentage share decreased with the age of the development group (for 51.91 from 43.13%). However, in the case of mycorrhizal fungi, an opposite trend was observed (16.96-26.75%). The most numerous genera were: saprotrophic (2.54-3.83%), (6.47-12.86%), (1.39-11.78%), pathogenic (0.53-4.39%), and mycorrhizal (1.80-5.46%), (2.94-5.64%) and (4.54-15.94%). The species composition of rhizosphere fungal communities was favorable for the regeneration of natural spruce and the development of multi-generational Norway spruce stands. The ratio of the abundance of saprotrophic and mycorrhizal fungi to the abundance of pathogens was high and promising for the durability of the large proportion of spruce in the Wigry National Park and for forest ecosystems in general.
Topics: Rhizosphere; Abies; Picea; Poland; Parks, Recreational; Mycorrhizae; Pinus; Microbiota; Norway
PubMed: 37628809
DOI: 10.3390/ijms241612628 -
Marine Drugs Jan 2024Co-cultivation, coupled with the OSMAC approach, is considered an efficient method for expanding microbial chemical diversity through the activation of cryptic...
Co-cultivation, coupled with the OSMAC approach, is considered an efficient method for expanding microbial chemical diversity through the activation of cryptic biosynthetic gene clusters (BGCs). As part of our project aiming to discover new fungal metabolites for crop protection, we previously reported five polyketides, the macrolides dendrodolides E () and N (), the azaphilones spiciferinone () and 8-hydroxy-spiciferinone (), and the -naphtho--pyrone cephalochromin () from the solid Potato Dextrose Agar (PDA) co-culture of two marine sediment-derived fungi, and . However, some of the purified metabolites could not be tested due to their minute quantities. Here we cultivated these fungi (both axenic and co-cultures) in liquid regime using three different media, Potato Dextrose Broth (PDB), Sabouraud Dextrose Broth (SDB), and Czapek-Dox Broth (CDB), with or without shaking. The aim was to determine the most ideal co-cultivation conditions to enhance the titers of the previously isolated compounds and to produce extracts with stronger anti-phytopathogenic activity as a basis for future upscaled fermentation. Comparative metabolomics by UPLC-MS/MS-based molecular networking and manual dereplication was employed for chemical profiling and compound annotations. Liquid co-cultivation in PDB under shaking led to the strongest activity against the phytopathogen . Except for compound , all target compounds were detected in the co-culture in PDB. Compounds and were produced in lower titers, whereas the azaphilones ( and ) were overexpressed in PDB compared to PDA. Notably, liquid PDB co-cultures contained meroterpenoids and depside clusters that were absent in the solid PDA co-cultures. This study demonstrates the importance of culture regime in BGC regulation and chemical diversity of fungal strains in co-culture studies.
Topics: Coculture Techniques; Chromatography, Liquid; Tandem Mass Spectrometry; Metabolome; Culture Media; Glucose
PubMed: 38393037
DOI: 10.3390/md22020066 -
Medical Mycology Case Reports Sep 2023A mycotic infection manifesting as abdominal distension with free serous fluid accumulation in the coelomic cavity is documented in farmed rainbow trout. Histological...
A mycotic infection manifesting as abdominal distension with free serous fluid accumulation in the coelomic cavity is documented in farmed rainbow trout. Histological examination using PAS and silver staining revealed the presence of numerous fungal hyphae in the spleen and gastrointestinal wall. The isolated fungus was sterile and identified by using phylogenetic analysis based on four loci as . This is the first time this fungus has been reported as pathogen.
PubMed: 37274730
DOI: 10.1016/j.mmcr.2023.05.001