Evaluation of intercropped soybean-sorghum compared to sole cropping of soybean

In order to find the best planting pattern of soybean (Glycine max L. Merill) with sorghum (Sorghum bicolor L.) intercropping for utilizing environmental parameters to obtain high yield, this research was performed in Gorgan and Ali Abad. The experiment consisted of three levels i.e. pure soybean with density of 400000 plants per hectare, intercropping of sorghum and soybean with density of 250000 and 400000 plants per hectare, respectively and intercropping of sorghum and soybean with density of 300000 and 480000 plants per hectare, respectively. Each treatment was comprised of sixty 66.66 - meter long rows. Row distance was 50 centimeters. For measuring plant height, number of tillers, stem diameter and number of nodes, 10-randomly selected plants within a quadrat were harvested. In addition, total surface area was recorded based on research and extension project protocol. Analysis of the data was performed using t-test. The results revealed that the fresh forage yield with intercropping at 300000 and 480000 plant density for sorghum and soybean, respectively were 33.33 and 34.32 percent superior in Gorgan and Aliabad, respectively compared to the check treatment (pure sorghum with the density of 250000 plants per hectare). Mean comparison of dry forage also indicated 24.01 and 26.12 % increase in Gorgan and Ali Abad, respectively.