Abstract only

A three-year field experiment was conducted to study the productivity, soil fertility and N-use efficiency of intensified RW systems by adding a third pre-rice crop of mungbean under five N levels (0, 50, 100, 150 and 200% N of recommended doses), two straw managements (straw retention and straw removal) and two tillage options (raised bed and conventional practice). System productivity, soil fertility and N-use efficiency were increased with increasing N levels up to 150% (150 kg N ha-1) in wheat, 100% (80 kg N ha-1) in rice and 100% N (20 kg N ha-1 ) in mungbean with bed planting system for all three years. Straw management showed slightly increasing effect on these aspects. After three years of cropping, organic matter, organic carbon, exchangeable K and available P, S, Ca, Mg, Mn and B were slightly increased, while available Zn, Fe and Cu slightly decreased with straw management system. Bulk density, infiltration rate and per cent total pore space slightly decreased with 0-10, 10-20 and 20-30 cm depth. System levels of grain, straw and total N uptake by mungbean were significantly influenced by straw incorporation compared with straw removal with both tillage options. However, physiological efficiency decreased with increasing N-rates up to 200% N application for all crops. But recovery and agronomic efficiency were increased with increasing N rates up to 100% N in rice and wheat with permanent bed system. Partial factor productivity for 3 crops and RE and AE were decreased with increasing N rate up to 200% N application under conventional system. System level grain, straw and total N uptake increased with increasing N rates up to 200% for all crops with bed planting system but they were statistically similar to that with 150% N. The inclusion of mungbean in the cropping system greatly increased the total system productivity and soil fertility. Between the two straw managements, straw retention with permanent bed showed better performance for all parameters. The best performance in respect of crop productivity, soil fertility and N-use efficiency were observed with 150% N for wheat and 100% N for rice and mungbean under raised bed system. While farmers may also improve their diet with mungbean grain, however, the residual effect of mungbean, even with straw as mulch, is not significant in short-run, but total system productivity has improved greatly through the inclusion of mungbean in the RW system. Long-term experiments are required to establish the potential benefits of legumes in increasing TSP, soil fertility and system-level N-use requirement and efficiency of intensified RW systems of Bangaldesh.

Conservation Agriculture Program

English

0903

Jose Juan Caballero

CSAY01

CIMMYT Staff Publications Collection