Effect of Superabsorbent Polymers on Some Morphological Characteristics of Olive Cultivars  Baghmalek and  Dezphol Under Water Deficit

Iran is located in arid and semi-arid regions, so limitation of precipitation and poor distribution of rainfall with prolonged periods of heat and drought have caused harsh conditions for establishing plants. In general, previous researches have shown that water deficit or drought stress had destructive effects on morphological, physiological and biochemical parameters of plants. So that, researchers stated that the first reaction of plants to water stress was decline in growth. Growth parameters such as height, fresh and dry weight of root and stem and leaf area could decrease with increasing water stress. Therefore, use of methods for reducing water evaporation from soil, decreasing run-off and improving transport nutrients were considered in recent years. Superabsorbant polymers are one of the most important compounds in reducing negative effects of drought on plants.
This study was conducted to investigate the effect of five different levels of super AB A200 polymer (0, 1, 2, 3, 4 g/Kg of soil) and three levels of irrigation [100 as control, 65 and 30 percentage of plant evapotranspiration potential (ETcrop)] on morphological characteristics of two olive cultivars ‘Baghmaleki’ and ‘Dezphol’ as a factorial experiment based on randomized complete block design with three replications. In this experiment, ninety 18-month-old olive trees of ‘Baghmaleki’ and ‘Dezphol’ were kept for adaptation in greenhouse for one month.The plants were planted in ninety pots including 1/3 sand, 1/3 manure and 1/3 soil with superabsorbent polymer. Superabsorbent polymers (super AB A200) were prepared from Company Rahab Resin (Licensed by Iran Polymer and Petrochemical Institute). Then, the plants were irrigated with 100%, 65% and 30% ETcrop, every three days. Finally, morphological parameters such as root fresh weight, root dry weight, shoot fresh weight, shoot dry weight, height, leaf number, leaf Area and leaf area ratio were measured. Data analysis was performed using MSTATC software and mean comparison was done by Duncan's multiple range tests at 5 and 1% probability.
The results showed that interaction effect between irrigation and polymer affected shoot fresh weight, leaf fresh weight, shoot dry weight, leaf dry weight, height and leaf area ratio at p