Mtui, H. D.; Maerere, A. P.; Bennett, M. A.; Sibuga, K. P.
Description:
In many areas in Tanzania, pests management for tomato involves weekly pesticide
sprays. The practice poses a threat to the environment and health of consumers. In this
study the effect of pesticide spray regimes and use of mulch were evaluated on ‘Tanya
VF’ and ‘Tengeru 97’ tomato varieties. Field experiment consisting of a 2×2×4 factorial
arrangement in a split-split plot design with three replications was conducted at Sokoine
University of Agriculture, Morogoro (6o05’S, 35o37’E and 525m above sea level).
Treatment factors comprised two varieties (main plot factor), mulching/number of
mulching (subplot factor) and three fungicide spray regimes (sub subplot factor).
Results showed that the spray regimes: farmers’ practice (FP), Integrated Pests
Management (IPM) based on pests scouting, sprays based on manufacturers’
recommendation (MR); produced significantly more fruits per plant and higher fruit
weight compared to the control. There was no significant difference (p < 0.05) between
FP, IPM and MR on fruit yield parameters. The results further revealed that use of
mulch significantly led to higher fruit number per plant (p = 0.020). Although average
fruit weight was similar (p < 0.05), other marketable fruit yield parameters were
statistically different between mulched and non-mulched plots (p = 0.007). ‘Tanya VF’
had consistently higher yields compared to ‘Tengeru 97’. Fungicide sprays were
statistically different to the control with respect to blossom end rot (p = 0.002), fruit rot
(p < 0.001) and percentage of non-marketable yield (p = 0.001). Mulching significantly
reduced American bollworm and blossom end rot (p = 0.012, p = 0.003, respectively).
The major contributor to tomato fruit loss was Blossom End Rot (BER) and Fruit Rot
for ‘Tengeru 97’ and ‘Tanya VF’, respectively. It is evident, therefore, that: a proper
combination of tomato cultural management practices can significantly reduce the use of
pesticides, and improve tomato fruit quality and marketable yield which would increase
profit margin accrued by farmers.