Effect of zeolite application on yield and physiological characteristics of wheat (cv. Roshan BC) in drought stress condition

Overall, more than three-quarters of energy and protein required for half of mankind comes from cereals (Emam, 2005). The most sensitive stage to drought stress in cereals between heading to flowering and cultivars, before flowering to increase a high dry matter production and assimilate in stem, the cultivars are drought tolerant (Niknam, 2005). Osmotic adjustment for drought tolerance as a trait known (Richard, 2004). So osmotic adjustment in leaf and pollen can be used as an indicator in breeding for increased tolerance to drought stress used (Delperee et al., 2003 ; Maghsoudi Moud and Yamagishi, 2005). Drought stress has significant effects on traits related to reproductive growth stage of crops including grain yield, yield components, harvest index and day to physiological maturity (Gol-Abadi et al., 2008). Also drought stress from flowering to grain handling, accelerated aging and reduce grain filling period (Royo et al., 2000). The aim of this study was to evaluate the chlorophyll concentration and wheat biological yield under drought stress and different levels of zeolite.
This study was carried out in field of Arak Payam Noor University in 2009. A split-plot arrangement of treatment in a randomized complete block design with three replications was used. Water stress (I0= Control irrigation, I1= Irrigation about 85% plant water requirement, I2= Irrigation about 70% of plant water requirement, I3= Irrigation about 55% of plant water requirement, were assigned in the main plots and different levels of zeolite application (Z0= without zeolite application, Z1= 3 ton ha-1, Z2= 6 ton ha-1, Z3= 9 ton ha-1) in sub plots. Each sub plot consisted of 4 rows, 5 m long with 50 cm between rows space and 5 cm between plants on the rows. In this study characteristics such as: Harvest index of spike, Biological yield of plant, Special leaf area, Spike density, b Concentration of b chlorophyll, Electrical conductivity of methanol treatment and Electrical conductivity of aseton treatment were assessed.
Results indicated that un-stress irrigation (control irrigation) with average electrical conductivity of methanol treatment (2835 µs cm-1) and zeolite application (9 ton ha-1) with average (2829 µs cm-1) were significantly superior to the other treatment. With increasing water stress, due to limitations in the absorption of water and nutrients to the plant caused reduced the growth of the plant. So finding ways that they can reduce the limitations caused by water stress, will be very convenient. In this experiment, the traits chlorophyll b, the electrical conductivity of methanol treatment (12 hours), electrical conductivity treatment with acetone (3 hours), specific leaf area, spike density, grain yield, biological yield and harvest index were affected by water stress. Also, Zeolite consumption as well as improved characteristics of electrical conductivity treatment of methanol (12 hours), specific leaf area, yield and biological yield of the plant.9 tons per hectare zeolite increased grain yield relative to the treatment of no zeolite was 20.18 percent. So we can say that the use of Zeolite to reduce the adverse effects of water stress on the plant.