Nutrient management for submergence-prone rainfed lowlands:

Many submergence-prone systems are not affected by other major soil constraints, however, they might be simultaneously affected by salinity (especially at the beginning and the end of the season) or drought.

Nutrient management in this environment is often restricted to good nursery management and basal applications because later applications are not helpful due to the high water levels.

Nutrient management options are:

• Good nursery management (discussed in this lesson) provides healthy and taller seedlings which increases the survival rate in the event of submergence. Best combined with submergence-tolerant varieties. Lower seeding density in the nurseries improves seedling health and submergence tolerance.

• If submergence-tolerant varieties are available, medium rates of inorganic fertilizer (about 40:30:30 kg NPK per hectare) can be applied as basal fertilizer during land preparation (rates are given in N:P2O5:K2O).

Submergence tolerance varieties. Vacant plots were occupied by the flood-susceptible check IR42.