18. Tomato (Lycopersicon Esculentum Mill.) Yield Performance under Elevated Dry Season Temperatures as an Adaptation to Climate Change in Tabora, Tanzania

Tomato growing is an adaptation strategy to rainfall variability and droughts that frequently result into loss of the maize crop during the rainy season. This study assesses yield performances of tomato genotypes under elevated dry season air temperatures in semi-arid environments as a climate change adaptive practice. Tomato is mostly grown in June through August months. The dry season is characterized by maximum daily temperatures (34.2 °C), low night temperatures (14.8 °C) and monthly evaporation of 168.2–226.6 mm between July and October. The atmospheric humidity is between 46 and 52 % in the same period. Highly significant yield at (P = 0.01) differences were found between the tested genotypes; Oxyl, Tanya Mkulima and Tengeru. Tomato planted in the month of August gave very low yields compared to the June planted crop. Low tomato yields were recorded on smallholders’ farms. Infestation by red spider mites (Tetranychus evansi) increased with increasing temperatures and reduced irrigation. Application of NPK with secondary nutrients Ca, Mg, S, and Zn improved tomato yield under elevated air temperatures.