Incidence, Distribution and Characteristics of Major Tomato Leaf ...

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6- We established that weeds act as alternative hosts to some tomato viruses
identified, which lead to a clear understanding of the necessity for timely weeding
of tomato fields as an option for virus disease management.
7- Majority of Ugandan tomato growers are smallholder farmers. They try to avoid
risks related to farming by growing a multiplicity of crops, and this practice
contributes to creating a complex nature of the agro-ecosystem favourable for
both tomato viruses and their vectors.
8- It was found that whiteflies preferred young tomato plants to old plants. It is
recommended that whiteflies be controlled at nursery stage before transplanting
seedlings, before infection or when vector and disease levels are still very low.
9- Uprooting diseased plants and applying dimethoate was an effective control for
whitefly vectors. Tomato growers are advised to apply this integrated
management package for TYLCV (sensu lato) and whitefly vector control,
especially if done during the dry season and the first part of the rainy season when
whitefly populations are high. In this way, farmer expenditure on pesticides
would be minimized and the amount of pesticides filtering through to the
environment would be tremendously reduced, even though both economic
analysis and evaluation of pesticide pollution were not conducted.
10- Having known major viruses infecting tomato, identified causal organisms of
yellow leaf curl symptoms and their vector, and established appropriate integrated
management practices, future research efforts should focus on the following;
conduct a survey of tomato viruses to cover agro-climatic zones that were not
surveyed during our study;
investigate further the biodiversity, incidence, host range and mode of
transmission of ChiVMV in Uganda;
investigate the occurrence of TYLCV-UG and ToLCV-UG in other districts of
Uganda; and study its biodiversity in relationship with whitefly vectors observed
on tomato and on other plants within the tomato agro-ecosystem.
evaluate tomato varieties, both transgenic and non-transgenic, for resistance to
TYLCV-UG and ToLCV-UG.