A STUDY OF THE DEVELOPMENT OF THE ROOT SURFACE MICROFLORA DURING THE INITIAL STAGES OF PLANT GROWTH

SUMMARY: A study of the development of the microfloras on the seeds and roots of tomatoes and oats during germination and subsequent root development showed a rapid selective multiplication on the seed during the initial stages of germination and also on the root almost immediately after emergence. Evidence is presented that further development of the root surface population after the initial high rate of multiplication was dependent on the normal development of the plant.
Direct microscopic observations of the micro-organisms of the root surfaces showed interesting differences between the roots of tomatoes and oats. In the former, the root hairs of young plants were free from bacteria but in the oats even young root hairs supported large numbers of organisms. In both plants the root tips were invariably free from organisms.