Influence on plant growth of the breakdown of organic phosphorus compounds by micro-organisms

Summary

Micro-organisms which break down lecithin or phytin have been isolated from soil by enrichment cultures. Only those organisms were investigated which on an agar medium containing lecithin or phytin as the sole source of P (in the case of lecithin, also as a source of N and energy), produced a clear area around their colonies. Certain of these organisms were inoculated into sterile cultures of radish plants grown on sand or agar substrates containing lecithin or phytin as the source of P, and the growth and N- and P-uptakes of the plants were compared with those of similar plants grown in non-sterile sand cultures or supplied with KH₂PO₄. Evidence was obtained that both lecithin and phytin can serve as P-sources for higher plants even under sterile conditions, phytin producing a greater effect than lecithin. Inoculation, however, had only in the phytin-containing medium sometimes a slight effect on the P-nutrition of the plants and further work in this field is therefore necessary.