Fusarium crown and root rot of tomatoes in the UK

Abstract

Fusarium crown and root rot caused by Fusarium oxysporum f. sp. radicis‐lycopersici was found in the UK in 1988 and 1989 mainly in rockwool‐grown tomato crops. Up to 14% of plants were affected in individual crops. In experiments, leaf and stem symptoms did not appear until the time of first fruit harvest even when the plants were inoculated at planting, first flowers or fruit set. Conidial inoculum at 106 spores/plant applied at seed sowing killed 70–83% of tomato seedlings, whereas similar levels of inoculum applied to young plants caused root and basal stem decay, and eventually death but only after fruit harvest began. Disease incidence and symptom severity increased with inoculum concentration. Experimentally, the disease was more severe in peat‐ or compost‐grown plants than in rockwool. Disease spread was only a few centimetres in 50 days in experimental rockwool‐grown plants. All tomato cultivars tested were highly susceptible. Prochloraz‐Mn was highly effective against the pathogen in vitro and controlled the disease in the glasshouse, but only when applied preventively. Non‐pathogenic Fusarium oxysporum isolates and Trichoderma harzianum also reduced FCRR disease levels.

Management of tomato diseases caused by Fusarium oxysporum

“…Contamination of tomato seeds by Forl was detected at a low incidence (0.1e0.01 %) in fruit on stem-infected plants, and also occurred through transmission by the Forl-infested hands of workers (Menzies and Jarvis, 1994). Tomato transplants infected by Forl have been implicated in the long distance spread of the fungus (Hartman and Fletcher, 1991;McGovern and Datnoff, 1992). McGovern et al (1993) determined that outbreaks of FCRR were linked to the infection of tomato transplants grown in reused Styrofoam and plastic transplant trays contaminated by Forl.…”

Advances in the Biology and Management of Monosporascus Vine Decline and Wilt of Melons and Other Cucurbits

“…An association among fruit load, fruit maturity, and disease expression has been reported with diseases of other crops. For example, with Fusarium crown rot of tomato (Hartman and Fletcher, 1991), leaf and stem symptoms did not appear until the time of first fruit harvest, and wilting plants recovered when fruit load was reduced by picking, but the phenomenon is not well documented for other soilborne diseases of melon. Fruit removal at fruit set had no effect on muskmelon vine decline caused by Macrophomina phaseolina and only a minor effect on vine decline caused by Acremonium cucurbitacearum .…”

Characterization and selection ofBacillus sp. strains, effective biocontrol agents againstFusarium oxysporum f. sp.radicis-lycopersici, the causal agent of Fusarium crown and root rot in tomato

“…radicis-lycopersici (FORL), was discovered in Japan (Yamamoto et al, 1974), and subsequently identified in many other regions, including North America, Europe, and Israel. In the United Kingdom, the disease was identified in 1988 (Hartman and Fletcher, 1991) and was subsequently confirmed in several nurseries (Green et al, 2003). An increase in early injury to the roots and collar of tomato plants caused by FORL was also observed in Tunisia (Hajlaoui et al, 2001).…”