Responses of the Soil Microflora to Volatile Components in Plant Residues

Exposure of soil to volatile substances from alfalfa ( Medicago sativa L.) hay, corn ( Zea mays L.) leaves, and other plant residues induces an immediate rise in the respiration rate of the soil microflora. This if followed by an increase in bacteria numbers and by vegetative growth of fungus mycelia over the soil surface. These volatiles, active at a distance from the plant residue, may function as respiratory and growth stimulants for soil microorganisms in the initial stages of colonization of residue.