Assessment of Sesbania aculeata as green manure in rice-wheat cropping system

Field studies were conducted in permanent layout in Rice-Wheat cropping system in Punjab Pakistan from 2012-13 to 2016-17 to assess the inclusion of Sesbania aculeata (locally called jantar) in crop rotation as green manure. Soil was alkaline with pH of 7.9-8.0 and loam in texture. Sesbania was broadcasted in standing wheat crop in mid of March followed by last irrigation to wheat crop. Wheat was harvested in mid of April followed by irrigation to standing sesbania. Sesbania was incorporated into soil by disc plough or rotavator near flowering. During summer season, the plot was divided into half; in first half recommended dose of fertilizer (N-P2O5-K2O @135-90-60 kg/ha) was applied whereas in other half fertilizer was applied at half recommended dose to rice. These two practices were compared with common practice of fallow between wheat and rice. Rice was followed by wheat crop with uniform fertilizer dose. Experimental results indicated that green manuring of sesbania increased paddy and wheat yield of following crop. Both in Rice and Wheat, plot with half of fertilizer out yielded recommended dose when jantar was incorporated. Chemical analysis of soils of experimental sites indicated that organic matter increased in sesbania incorporated plots.