Soil moisture variations and growth characteristics of Russian olive seedlings as affected by pumice in rainfed conditions

One of the strategies for efficiently using agricultural water resources and preserving them is to use absorbent materials such as pumice in soil. The present research aimed to evaluate the effects of different levels of pumice on soil water content and Russian olive seedling growth. For this purpose, an experiment was designed and conducted as a randomized complete block design with four treatments and three replications from 2017 to 2018 in the Khajeh Research Station. Treatments included control (no pumice), and 10%, 20%, and 30% pumice. During the experiment, the average soil moisture content was measured by TDR every 10 days. The growth characteristics of the Russian olive seedlings, including seedling height, collar diameter, and leaf area were measured. Minimum soil water content was recorded for the control treatment and then a significant increase was observed by increasing the use of pumice. In the control treatment, seedling height, collar diameter, and leaf area were 56 cm, 6.2 mm, and 108 cm2, respectively, while in the 30% pumice treatment, the same characteristics were significantly increased to 105 cm, 11.4 mm, and 201 cm2, respectively. So, by increasing the amount of pumice from 0 to 30%, seedling height, collar diameter, and leaf area increased by 87, 84, and 86%, respectively. Therefore, we can conclude that pumice by retaining soil water during the growing season, especially in rainfed conditions, prevents plant water-deficit stress and enhances its growth and development.