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Peanuts (Arachis hypogaea) are of significant agricultural importance due to their versatile uses, providing a valuable source of edible oil and protein-rich food products and serving in industrial applications. Peanuts are susceptible to various diseases, one of them being net syndrome, a poorly understood threat triggered by an undefined causal agent, with symptoms including black coloring and lesions of the peanut pod that affect product quality. In this study, amplicon sequencing was harnessed to explore the fungal and bacterial populations associated with the syndrome. Using this approach, we identified a specific Fusarium sp. amplicon sequence variant that demonstrated a significant correlation with the presence of net syndrome symptoms in both young and mature peanuts. This finding was further validated by Koch's postulates testing, including isolation, cultivation, and application of this strain to corroborate its involvement in net syndrome in peanuts. Our findings contribute to a better understanding of the interactions between peanuts and their microbial communities and to identification of the previously undetermined agent involved in net syndrome and the etiology of the disease.

Organic amendment, and especially the use of composts, is a well-accepted sustainable agricultural practice. Compost increases soil carbon and microbial biomass, changes enzymatic activity, and enriches soil carbon and nitrogen stocks. However, relatively little is known about the immediate and long-term temporal dynamics of agricultural soil microbial communities following repeated compost applications. Our study was conducted at two field sites: Newe Ya'ar (NY, Mediterranean climate) and Gilat (G, semi-arid climate), both managed organically over 4 years under either conventional fertilization (0, zero compost) or three levels of compost amendment (20, 40 and 60 m3/ha or 2, 4, 6 L/m2). Microbial community dynamics in the soils was examined by high- and low-time-resolution analyses. Annual community composition in compost-amended soils was significantly affected by compost amendment levels in G (first, second and third years) and in NY (third year). Repeated sampling at high resolution (9–10 times over 1 year) showed that at both sites, compost application initially induced a strong shift in microbial communities, lasting for up to 1 month, followed by a milder response. Compost application significantly elevated alpha diversity at both sites, but differed in the compost–dose correlation effect. We demonstrate higher abundance of taxa putatively involved in organic decomposition and characterized compost-related indicator taxa and a compost-derived core microbiome at both sites. Overall, this study describes temporal changes in the ecology of soil microbiomes in response to compost vs. conventional fertilization.

Measurement(s) pH measurement • temperature of water • concentration of oxygen in water • total phosphorus • ammonia • concentration of nitrate in water • concentration of nitrite in water • concentration of chlorophyll a in water • concentration of chlorophyll b in water • concentration of beta-carotene in water • concentration of fucoxanthin in water • Dinoxanthin • Diadinoxanthin • Diatoxanthin • concentration of zeaxanthin in water • concentration of lutein in water • microcystin-LR • library DNA concentration Technology Type(s) pH Meter • Temperature Probe Device • electron spin resonance oximetry • colorimetry • colorimetry • liquid chromatography-photodiode array detection • liquid chromatography-photodiode array detection • microcystins/Nodularins ADDA Elisa • PicoGreen Dye Factor Type(s) Geographic location • Isolaion source • Depth • latitude • longitude Sample Characteristic - Environment freshwater biome Sample Characteristic - Location Israel

Bacillus cereus sensu lato (Bcsl) strains are widely explored due to their capacity to antagonize a broad range of plant pathogens. These include B. cereus sp. UW85, whose antagonistic capacity is attributed to the secondary metabolite Zwittermicin A (ZwA). We recently isolated four soil and root-associated Bcsl strains (MO2, S−10, S-25, LSTW-24) that displayed different growth profiles and in-vitro antagonistic effects against three soilborne plant pathogens models: Pythium aphanidermatum (oomycete) Rhizoctonia solani (basidiomycete), and Fusarium oxysporum (ascomycete). To identify genetic mechanisms potentially responsible for the differences in growth and antagonistic phenotypes of these Bcsl strains, we sequenced and compared their genomes, and that of strain UW85 using a hybrid sequencing pipeline. Despite similarities, specific Bcsl strains had unique secondary metabolite and chitinase-encoding genes that could potentially explain observed differences in in-vitro chitinolytic potential and anti-fungal activity. Strains UW85, S-10 and S-25 contained a (~500 Kbp) mega-plasmid that harbored the ZwA biosynthetic gene cluster. The UW85 mega-plasmid contained more ABC transporters than the other two strains, whereas the S-25 mega-plasmid carried a unique cluster containing cellulose and chitin degrading genes. Collectively, comparative genomics revealed several mechanisms that can potentially explain differences in in-vitro antagonism of Bcsl strains toward fungal plant pathogens.