Agricultural quality matrix-based multiomics structural analysis of carrots in soils fertilized with thermophile-fermented compost

TL;DR

This study investigates how compost fermented with thermophilic bacteria affects carrot growth, quality, and soil microbiome, revealing complex interactions that enhance productivity and nutritional content through multiomics analysis.

Contribution

It introduces a multiomics structural analysis approach to understand soil-plant interactions influenced by thermophile-fermented compost, highlighting new insights into sustainable agriculture.

Findings

Compost increased carrot productivity, antioxidant activity, and taste.

Altered soil bacterial composition with characteristic metabolites.

Structural equation modeling linked key metabolites and microbes to compost exposure.

Abstract

Compost is used worldwide as a soil conditioner for crops, but its functions have still been explored. Here, the omics profiles of carrots were investigated, as a root vegetable plant model, in a field amended with compost fermented with thermophilic Bacillaceae for growth and quality indices. Exposure to compost significantly increased the productivity, antioxidant activity, red color, and taste of the carrot root and altered the soil bacterial composition with the levels of characteristic metabolites of the leaf, root, and soil. Based on the data, structural equation modeling (SEM) estimated that L-2-aminoadipate, phenylalanine, flavonoids and / or carotenoids in plants were optimally linked by exposure to compost. The SEM of the soil estimated that the genus Paenibacillus, L-2-aminoadipate and nicotinamide, and S-methyl L-cysteine were optimally involved during exposure. These estimates did not show a contradiction between the whole genomic analysis of compost-derived Paenibacillus isolates and the bioactivity data, inferring the presence of a complex cascade of plant growth-promoting effects and modulation of the nitrogen cycle by compost itself. These observations have provided information on the qualitative indicators of compost in complex soil-plant interactions and offer a new perspective for chemically independent sustainable agriculture through the efficient use of natural nitrogen.