ABSTRACT Fusarium oxysporum f. sp. radicis-lycopersici, the causal agent of 
Fusarium crown and root rot of tomato, and F. oxysporum f. sp. basilici, the 
causal agent of Fusarium wilt in basil, are soilborne pathogens capable of 
producing conspicuous masses of macroconidia along the stem. The role of the 
airborne propagules in the epidemics of the disease in tomato plants was 
studied. In the field, airborne propagules of F. oxysporum f. sp. 
radicis-lycopersici were trapped with a selective medium and their prevalence 
was determined. Plants grown in both covered and uncovered pots, detached from 
the field soil, and exposed to natural aerial inoculum developed typical 
symptoms (82 to 87% diseased plants). The distribution of inoculum in the growth 
medium in the pots also indicated the occurrence of foliage infection. In 
greenhouse, foliage and root inoculations were carried out with both tomato and 
basil and their respective pathogens. Temperature and duration of high relative 
humidity affected rate of colonization of tomato, but not of basil, by the 
respective pathogens. Disease incidence in foliage-inoculated plants reached 75 
to 100%. In these plants, downward movement of the pathogens from the foliage to 
the crown and roots was observed. Wounding enhanced pathogen invasion and 
establishment in the foliage-inoculated plants. The sporulation of the two 
pathogens on stems, aerial dissemination, and foliage infection raise the need 
for foliage protection in addition to soil disinfestation, in the framework of 
an integrated disease management program.