The effect of cattle manure and zeolite on bread wheat yield under drought stress condition

Introduction According to statistical yearbook of agriculture in cropping season of 2015-2016, Khuzestan province with wheat area harvested about 535 thousand hectares, production of 1.86 million ton and average yield of 4.4 ton per hectare had the first place between other provinces in the country. In recent years there was a shortage in water for irrigated wheat farms, therefore irrigated and rain-fed farms have drought stress. In water stress conditions, reduced yield and yield components of wheat. One of the important ways to reduce the negative effect of drought stress on plant is using animal manures and zeolite in the soil. Using animal manure in agricultural soils lead to increase nutrient elements and conserving the soil water. Also using zeolite in soils cause increase soil water and decrease the negative impacts of drought stress on plant. Generally, manure and zeolite contribute to preserving the moisture storage of the soil and to supply the nutrients required by the plant. In this study, the most important aim is to study the effect of cattle manure and zeolite on bread wheat yield and yield components under water stress condition in Ahwaz condition. Materials and methods In order to evaluate wheat response to using cattle manure and zeolite under drought stress condition, a field experiment using split-factorial design based on randomized complete block with three replicates was conducted in research farm of Agricultural Sciences and Natural Resources University of Khuzestan (in 31º N, 48º E, 35 Km north-east of Ahwaz, and 20 m above the sea level) during 2016-2017 cropping season. Experimental factors were three levels of irrigation cutoff (without irrigation cutoff (control), irrigation cutoff from milky-dough stage to physiological maturity and irrigation cutoff from flowering stage to physiological maturity) in main plots and three rates of cattle manure (0, 15 and 30 ton/ha) and three rates of zeolite (0, 6 and 12 ton/ha) in sub plots. Results and discussion Results showed that the effect of irrigation cutoff, cattle manure and zeolite and interaction effect of cattle manure and zeolite were significant of more measured traits. The mean comparison of interaction effect indicated that using 30 ton/ha cattle manure and 12 ton/ha zeolite than control increased grain yield by 70 percent in complete irrigation and 72 percent in irrigation cutoff from milk-dough stage to physiological maturity. Also, in irrigation cutoff from flowering stage to physiological maturity, using 15 ton/ha cattle manure and 12 ton/ha zeolite increased grain yield by 82 percent. Therefore, in regions with irrigation shortage or lack of rainfall in the milky-dough stage, 30 tons per hectare manure and 12 tons per hectare of zeolite are recommended for increasing grain yield. Conclusions Generally, the results showed that drought stress decreased grain yield of wheat but using cattle manure and zeolite decreased the negative impact of drought stress. Means comparison of interaction effect showed that in full irrigation condition could use 30 ton/ ha of cattle manure and 12 ton/ha zeolite to producing the highest grain yield. In irrigation cut-off from milky-dough stage to physiological maturity, using 30 ton/ ha of cattle manure and 12 ton/ha zeolite decreased the effect of drought stress on wheat yield. Also, in areas with irrigation shortage or lack of rainfall at the beginning of flowering stage, 15 tons per hectare of manure and 12 tons per hectare of zeolite are recommended for maintaining grain yield.