Evaluation of Competition and Advantage in Barley (Hordeum vulgare L.) and Forage Pea (Pisum sativum L.) Intercropping under Rainfed Condition

In order to evaluate of barley and forage pea intercropping in rainfed condition, an experminet was conducted as randomized complete blocks design (RCBD) with three replications at University of Maragheh, Iran in 2015. Treatments included sole cropping of forage pea with densities of 100, 150, 200, 250 and 300 plants.m-2, sole cropping of barley, 75% barley+ 25% forage pea (with mentioned densities), 50% barley+ 50% forage pea (with mentioned densities) and 25% barley+ 75% forage pea (with mentioned densities). The results domenstrated that dry forage yield of barley and pea were affected significantly by difeerent planting patterns. The highest and lowest dry forage yield of barley was obtained in sole cropping of barley (352.02 g.m-2) and 25% barley+ 75% forage pea with 300 plant.m-2 (103.7 g.m-2), respectively. Also, the highest dry forage yield of forage pea was obtained in pea sole cropping with density of 300 plant.m-2 (93.75 g.m-2). The highest land equivalent ratio (1.25) and standard land equivalent ratio (1.11) was obtained in 25% barley+ 75% forage pea with densities of 300 and 100 plant.m-2, respectively. In terms of competitive indices, in most tretaments the aggressivity and crowding coefficient values of pea were lower than of barley, indicating that barley was more competitive and dominant than forage pea. Positivity of intercropping advantages (IA), system productivity index (SPI) and actual yield loss (AYL) values in all cropping patterns indicate the useful effect of plants on each other and intercropping efficiency of plants under rainfed conditions.