Seed and mucilage yield of Plantago ovata Forsk. in different densities under rainfed and dry farming conditions of Golestan province

The effect of plant density on the seed yield and mucilage of Plantago ovata Forsk. was studied using a randomized complete block design under dry farming conditions at two stations: a) Maraveh-Tapeh , 240 km northeast of Gorgan, with a long-term average rainfall of 330 mm (low rainfall) and b) Chalaky station, 8 Km west of Gorgan with a long-term average rainfall of 550 mm (rainfed). The experimental plots were planted at densities of 100, 200 and 400 plants m-² with a distance of 20 cm between rows.Data were analyzed using a combined analysis. No significant differences were found for the effects of density on traits including seed number per spike, spike length, harvest index, 1000-seed weight and mucilage percentage, while there were significant differences for the spike number m-1, seed yield, and mucilage yield at 1% probability level. According to the results, the location effect was significant on spike number m-1, seed and mucilage yield (1% probability level), and harvest index (5% probability level). The interactions between plant density and location on spike number per square meter and seed and mucilage yield per hectare were significant at 1% probability level, while no significant differences were found for the other traits. The seed and mucilage yield increased with increasing plant density, so that the seed and mucilage yield at a density of 400 plants m-1 in the Chalaki station were 2.3 and 2.9 times and in the Maraveh-Tapeh station were 1.94 and 1.86 times more compared to 100 plants m-1, respectively. Seed and mucilage yield in Chalaky station were 1.71 and 1.69 times more compared to Maraveh-Tapeh station, respectively. Our results clearly showed superiority for all traits measured at a density of 400 plants m-1 in the Chalaky station as compared with other densities in both locations.