The black gram in Sikkim is sown in 5960 ha with average yield of 880 kg-ha-1. The sown area (2410 ha) of black gram is maximum in west Sikkim (Gyalshing) district. The black gram sowing (manual practice of broadcasting of seeds) is mostly done in July-August in terraces of Sikkim. The two row animal drawn improved zero till seed drill (weight: 23.7 kg, unit price: Rs. 2700, overall dimension: 730 * 940*735 mm) was tested for sowing black gram (seed rate: 15 kg-ha-1) at 275 mm row spacing after three weeks of normal sowing. The effective field capacity and field efficiency were 650 m2-h-1 and 65% respectively. The cost of operation was Rs. 580 ha-1. The use of zero-till seed drill saved 16% seeds over traditional sowing practice and yield was also higher (5.8%) due to line sowing of seeds. In east Sikkim, animal drawn light weight CAEPHT multi-purpose tool frame with seeding attachment (overall dimensions: 730*700*960 mm, weight: 19.8 kg, unit price: Rs. 8000/-, command area: 1.5 ha) was tested in terraces for sowing black gram at normal sowing period (July). It showed higher work rate (1250 m2-h-1) due to increased working width of 720 mm. The cost of operations was Rs. 400 ha-1. The tool frame with seeding attachment provided 4% more yield as compared to two row zero till seed drill and the crop yield was 9.8% more over manual sowing by traditional broad casting method.
Keywords: Light weight, zero-till, residual moisture, field capacity, working width, tool frame, broad casting.