Abstract

Salinity stress, drought and the lack of water supply are major constraints limiting rice productivity in rainfed lowland of the Sine Saloum region. To alleviate these constraints, several actions have been undertaken including construction of anti-salt dykes and using of salt tolerant varieties. The objectives of this study were: (a) analyze the hydraulic operation of these lowlands and salinity rate during wet season. (b) To test, the response of new salt-tolerant varieties, with different fertilizers and to identify the best suitable. Trials were conducted in two sites. The level of groundwater and salinity were measured during two wet seasons in two sites. At least 100 mm of rainfall are required to decrease salinity (EC) below 3 dS / m on a leveled land, before sowing. Before sowing, the management of water flow at the anti-salt dam must take into account not only the leaching of salt, but also the groundwater recharge. It is this groundwater that will allow rice to reach maturity, at the end of rains by mitigating late season drought. In both sites, D14 and IR70870-B-P-2-2 were the most biomass productive varieties. Among the eleven rice varieties tested, five have performed well with the average grain yields of 4 t.ha^-1.

Key words: Rainfall, groundwater, sea water, new salt-tolerant varieties, lowland.