THE DEVELOPMENT OF ENDOMYCORRHIZAL ROOT SYSTEMS: I. SPREAD OF INFECTION AND GROWTH‐PROMOTING EFFECTS WITH FOUR SPECIES OF VESICULAR‐ARBUSCULAR ENDOPHYTE

Abstract

SUMMARY Four vesicular‐arbuscular endophytes were inoculated into onions cultured in soil in a growth chamber. Dry weight, root length, infected root length, phosphorus content and quantity of external mycelium were measured at intervals. Three endophytes produced similar hyphal inflows, growth increments and external mycelium. One endophyte produced no growth increase in the host, and had little external mycelium and slow increase in percentage infection.