Investigating the Alleviation of Water Deficit Stress on Wheat Growth and Yield Using Zeolite and Fungus Piriformospora indica

In order to evaluate the effect of zeolite and Piriformospora indica fungi inoculation on wheat growth and yield under irrigation cut off condition, a field experiment was conducted in a split-factorial experiment based on randomized complete block design with three replications in the research farm of Agricultural Sciences and Natural Resources University of Khuzestan, during 2016-2017 growing season. Experimental factors were three levels of irrigation cutoff (without irrigation cut off, irrigation cutoff from milky-dough stage and irrigation cutoff from flowering stage) as the main plot and four rates of zeolite (0, 4, 8 and 12 ton.ha-1) and two levels of Piriformospora indica fungi inoculation (inoculation and non-inoculation) as sub plots. The results showed that the highest grain yield was obtained under full irrigation condition and application of 12 tons of zeolite per hectare (3849 kg. ha-1), and the lowest was obtained from irrigation cut off at flowering stage and no application of zeolite (1947 kg.ha-1). No significant difference was observed between different levels of zeolite under full irrigation conditions, while in the mild and severe drought conditions application of 8 and 12 tons of zeolite per hectare was advantageous. In irrigation cutoff at milky-dough stage condition, by fungi inoculation, seed yield increased from 3129 to 3647 kg.ha-1. Application of the fungus was effective in irrigation cutoff at flowering stage, such that the grain yield was raised from 2161 to 2917 kg.ha-1. The results of this study indicate that the use of zeolite in combination with soil and inoculation with Piriformospora indica fungi can somewhat compensate wheat grain yield damage in water deficit stress conditions.