IRRIGATTION WATER PRODUCTIVITY EVALUATION OF TOMATO IN THE NORTHERN NIAYES AREA IN SENEGAL

In the Niayes, irrigation of market garden crops is totally ensured by groundwater, which is the only available water source used in irrigation. However, this water source is vulnerable to the development of irrigated agriculture and the impact of climate change. This raises the challenge of optimizing irrigation in this area. The objective of this study is to evaluate tomato irrigation water productivity in the Lowlands of DeurDiabi, Lac Kalassane, FersetNdoye, BoulAyni and Nguethiouro in the Niayes. In this regard, surveys were carried out with 123 farmers in these five lowlands, focusing on irrigation management at plot level. The volumes of irrigation water supplied per plot and the yields are calculated on the basis of these surveys. Water productivity was determined based on water volumes supplied and yields. Results showed that the volumes of water supplied are very high compared to crop water requirements and yields are relatively low. Water quantities applied per season varied between 3330 m3/ha and 5000 m3/ha and yields varied between 18 t/ha and 27 t/ha. Thus, tomato water productivity is varied between 5.00 and 5.96 kg/m3 with an average of 5.18 kg/m3. These results show that tomato water productivity in this area is very low and has to be improved. These results can be of great contribution to irrigation optimization.