Diseases of tomato were investigated in four plots at a University farm located in Choba, a
community of the Niger Delta Region of Nigeria. Disease symptoms included irregular leafspots, dark brown lesions
with chlorotic halos, vein clearing, chlorosis, yellowing, blight, wilts and defoliation. Flower blight and drop was
observed in the plants that reached the flowering stage before dieing. Other symptoms were stunting, stem canker,
die-back, shriveling of stem and death.
Fusarium oxysporum f. sp.
lycopersici
,
Verticillium albo-atrum
and
Rhizoctonia solani
were the three fungi isolated on acidified potato dextrose agar from symptomatic roots and stems
of permanently wilted plant samples. Pathogenicity of isolates was established. There is evidence to suggest that
Fusarium, Verticillium and
Rhizoctonia spp. limit production of tomato in this part of Nigeria. The study also
confirms earlier reports that Fusarium wilt limits tomato production in the forest zone and also establishes
Verticillium wilt and Rhizoctonia stem canker and root rot as other important diseases limiting tomato production in
Rivers State. Therefore the production of tomato requires the development of efficient control systems to reduce
economic loss associated with these diseases.
