Soybean (Glycine max) growth, productivity and water use under different sowing methods and seeding rates in Punjab

A field experiment was conducted from 2006 to 2008 to study the effect of four sowing methods namely raised bed planting (67.5 cm wide, 2 rows per bed), raised broad bed planting (135 cm wide, 4 rows per bed), ridge-fur- row sowing (60 cm spacing) and flat sowing (45 cm spacing) and three seeding rates i.e. 50, 62.5 and 75 kg/ha in soybean [Glycine max (L.) Merrill]. The highest photosynthetically active radiation interception (PARI) and net re- turns were recorded in raised bed planting. The highest seed yields was recorded in raised bed sowing, which was 6.70 and 5.29% higher than ridge-furrow and flat sowing methods, respectively. The highest water productiv- ity was recorded in raised broad bed sowing which was significantly higher than flat sowing and ridge-furrow sow- ing methods but statistically on par with raised bed sowing. Seed rate of 50 kg/ha recorded highest crop growth rate (CGR) and pods per plant whereas the highest PARI was observed with 75 kg/ha seed rate, which was statis- tically on par with 62.5 kg/ha seed rate but significantly higher than 50 kg seed/ha. The soybean productivity and net returns were highest with 62.5 kg/ha seed rate.