Not very permaculture aye? Lots of mystic hand waving? Well… read on.
Ever wanted to know how “Preparation 500” is prepared? Or what’s in the end product?
The material was found to harbor a bacterial community of 2.38 × 10-8CFU/g dw dominated by Gram-positives with minor instances of Actinobacteria and Gammaproteobacteria. ARISA showed a coherence of bacterial assemblages in different preparation lots of the same year in spite of geographic origin. Enzymaticactivities showed elevated values of β-glucosidase, alkaline phosphatase, chitinase, and esterase. The preparation had no quorum sensing-detectable signal, and no rhizobial nod gene-inducing properties, but displayed a strong auxin-like effect on plants. Enzymatic analyses indicated a bioactive potential in the fertility and nutrient cycling contexts. The IAA activity and microbial degradation products qualify for a possible activity as soil biostimulants.
Of the bacterial species, two dominated 90% of the culture. Half was Bacillus megaterium a plant growth promoting rhizobacteria (PGPR) known to produce Cytokinin. While the other half was Bacillus safensis another PGPR known to produce Auxins.
Cytokinins promote cell division and act in concert with auxins that promote cellular expansion. And, for example, the ratio of auxin to cytokinin in certain plant tissues determines initiation of root versus shoot buds.
Sounds like it should be called PGPR 500.