For phytoremediation two different plants, rye (Secale cereale) and nitrogen fixing blue fenugreek (Trigonella caerulea) were chosen and cultivated using 10 seeds in each pot.
The Kruskal-Wallis one-way analysis of variance by ranks was applied to compare gene copy numbers and relative abundances between plant treatments (nonplanted, rye, blue fenugreek; n = 12 in each group) and bioaugmentation/biostimulation treatments (no treatment, biostimulation, biostimulation combined with bioaugmentation, n = 12 in each group).
In comparison, blue fenugreek cultivation had positive effect on TNT-degradation only in the variant with inoculum and amendments.
The type of plant cultivated (rye or blue fenugreek) resulted in no significant variance in microbial communities.
The second PCA axis separated samples according to the plant treatment; samples with blue fenugreek plants were discernible from both non-planted samples and from samples with rye cultivation.
As expected, cultivation of plants, especially blue fenugreek, generally had positive effect on the total bacterial 16S rRNA copy number per gram of soil irrespective of other treatment types used (Kruskal-Wallis test, P < 0.01).
Plants enhanced the total microbial community abundance, but in the case of blue fenugreek, cultivation did not significantly affect the TNT degradation rate.
It calls for fresh skimmed cow's milk to be blended with a special herb, Schabziger blue fenugreek
, which gives Sap Sago its soft herb-green hue and distinctive taste.