The effect of planting date and plant density on morphological traits, yield and water use efficiency of Plantago ovata

Given the importance of medical plants cultivation, in order to study the effect of planting date and plant density on morphological traits, yield and water use efficiency (WUE) of Plantago ovata, an experiment was conducted as a split-plot based on a Randomized Complete Block Design with three replications at experimental field of Islamic Azad University, Birjand Branch, Birjand, Iran in 2008. The main plot was planting date at three levels of April 19, May 9 and May 30, 2008 and the sub-plot was plant density at three levels of 16.6, 22.2 and 33.3 plants/m2. The results showed that the effect of planting date was significant on plant height, spike length, leaf number per plant, leaf, husk and grain yield, and WUE for grain production. Means comparison indicated that retarding the planting from April 19 to May 30 decreased plant height, spike length, leaf number/plant, husk, leaf and grain yield, and WUE for grain production by 24.5, 29.9, 18.2, 65.4, 60.2, 60.2 and 46.9%, respectively. The traits of plant height, spike length, leaf number per plant, tiller number per plant, leaf, husk and grain yield, and WUE for grain and biomass production were affected by plant density. As the results showed, with the increase in plant density from 16.6 to 33.3 plants/m2, plant height, grain yield and water use efficiency were increased by 7.8, 82.8 and 82.1%, respectively, but leaf number per plant, spike length and tiller number per plant were decreased by 24.8, 5.9 and 28.9%, respectively. The highest husk and leaf yield and WUE for biomass production was obtained at the density of 33.3 plants/m2 which were higher than those at the density of 16.6 plants/m2 by 2.11, 2.10 and 2.06 times, respectively. Swelling factor was not affected by planting date, plant density and their interactions. Also, the interaction between planting date and plant density significantly affected leaf, husk and grain yield and water use efficiency for grain production. In total, according to the results, the planting date of April 19 with the density of 33.3 plants/m2 is recommended to realize maximum yield and water use efficiency in Plantago ovata cultivation in Birjand region, Iran.

Keywords:

Plantago ovata , planting date , plant density , yield , WUE