Abstract:
Tomatoes, or Lycopersicum escutentum Mill (Solanaceae), are one of the most widely cultivated vegetable crops in Africa. They are grown for home consumption in the backyard of almost every homestead across sub-Saharan Africa. They are an important source of vitamins and an important cash crop for both smallholders
and medium-scale commercial farmers. Tomato yields in smallholder cropping
systems in the region are generally far below the potential of the crop. Average yields as low as 7 tonnes/ha have been reported from Tanzania and 10 t/ha from Uganda. while yields as high as 100 Uha have been recorded from commercial farmers in Zimbabwe. There are several reasons for the low yields. Among these
are low quality seeds, non-availability of inputs, sub-optimum crop husbandry, and a large number of pests and diseases. The major pests and diseases of tomatoes
in the region were prioritised at a Tomato Planning Workshop held in Harare, Zimbabwe in October 1995. The meeting was organised by the GTZ-IPM Horticulture Project with participants from Kenya, MozambiqLJe, Tanzania,
Uganda, Zambia and Zimbabwe. The main pests were identified as arthropod pests (red spider mites and russet mites), insects (frultworms, whiteflies, leafminers and thrips) and diseases (early and late blights, bacterial wilt, Fusarium wilt, bacterial canker and nematodes) (Table 1 ). Viral diseases were considered very Important
but they could not be prioritised ,due to lack of information. Recent surveys have shown that viral diseases are a major constraint to tomato production in the eastern and southern Africa region.