Tomato (Lycopersicon esculentum L.) is one of the most important vegetables in the world and its demand has increased and so factors affecting its production are key for evaluation. The yields of tomato in Ghana are low and supplemented by imports from neighbouring countries. This study investigated the effects of deficit drip irrigation and mulch on reproductive and yield traits of two tomato varieties. The experiment was carried out at Savannah Agricultural Research Institute (SARI) experimental field in Nyankpala, Tamale in Ghana from November 2020 to March 2021. It was a 2 x 3 x 3 factorial experiment laid out in a split-split plot design with two tomato varieties (Pectomech and Mongal F1), three drip irrigation regimes: 50%, 75% and 100% of actual crop evapotranspiration (ET 50, 75, 100) and three levels of rice straw mulch (0, 3 and 6 t/ha) in four replications. The output of the CROPWAT model indicated highest seasonal water requirement of tomato to be 564 mm at ET100 whilst the lowest of 282 mm at ET50. Significant (p<0.05) differences in flower count, flower abortion, fruiting and total fruit yield as influenced by irrigation regime and mulch were observed. Highest total fruit yield of 13.46 t/ha was obtained with combined use of Mongal F1 and of ET100, whilst the lowest of 2.04 t/ha was recorded from Pectomech tomato and ET50.

Keywords: Deficit irrigation; straw mulching, Pectomech, Mongal F1, total fruit yield.