Improving rice-based cropping systems in north-west Bangladesh: diversification and weed management

Improving total productivity in the rice-rabi cropping system in Bangladesh depends on elevating component yields whilst minimizing the risk of drought to both crops. Direct seeding of rice has the potential of advancing crop establishment with the onset of monsoon rains and allowing greater opportunities for subsequent rabi (chick-pea, mustard, linseed) crops on residual moisture as the dry season commences. Agronomic studies over three years indicated that rice yields could be increased over traditional transplanting by use of direct seeding in both a widely used (Swarna) and more recently introduced cultivar (BRRI dhan 39). Oxadiazon applied pre-emergence controlled major weeds but one manual weeding was needed for yield protection from weed competition from Altenanthera sessilis, Cyperus iria and Paspalum distichum in particular. Socio-economic evaluation indicated that adoption of direct seeded rice was more likely to occur on large farms where competition for labour at times of peak demand was intense and where there was a greater proportion of land area favourable for rabi cropping