A mature liquid fertilizer derived from cattle urine promotes Arabidopsis thaliana growth via hormone-like responses.

ABSTRACT

To understand the fertilization effects of liquid fertilizer (LF) produced by aerobic microbial processing of cattle urine, we investigated the influence of LF on growth and shoot genetic responses of the model plant Arabidopsis thaliana. LF significantly enhanced both shoot and root growth under aseptic conditions. Although filtrate from ultrafiltration (molecular weight cutoff 10 000) also promoted shoot growth and root elongation, the concentrate only promoted root growth. Multiple growth-promoting factors were therefore associated with the growth promotion. Transcriptome analysis of shoots following LF addition identified 353 up-regulated and 512 down-regulated genes. According to gene ontology and KEGG enrichment analyses, signal transduction of a phytohormone cytokinins was influenced by LF addition. Cytochrome P450 induction triggered the following signal transitions, and would introduce the growth promotion for shoot. Primary auxin responses and abscisic acid signaling responses were also observed in the presence of the LF. Ethylene signaling seemed to be insensitive.