عنوان مقاله [English]
نویسندگان [English]چکیده [English]
To evaluate the effect of foliar application of nano-particles of titanium dioxide on yield and yield components of ecotypes of cumin under drought stress conditions, a split-split plot experiment was carried out based on a randomized complete block design with three replications, during 2014-2015 at the research farm of Aburaihan Campus, University of Tehran at Pakdasht. Treatments were consisted of water stress at three levels (full irrigation throughout growing season, water stress at vegetative and reproductive stages), spraying of nano-particles of titanium dioxide at three levels (no spray, spraying with concentration of 0.015 and 0.03 percentages) and also ecotypes of cumin from nine regions. Based on the obtained results the highest grain yield was belonged to Ardakan-Yazd in normal irrigation and spraying of nano-particles at concentration of 0.03 percent with an average of 194.05 grams per square meter, compared to non-sprayed treatment in which 17 percent lower grain yield was obtained. The highest grain yield also was observed at stress conditions in reproductive phase for ecotype of Maneh of North Khorasan at spraying of 0.015 percent of nano-particles with an average of 45.89 grams per square meter, when compared to the control (no spray) in which 16 percent lower grain yield was obtained. Ecotypes also showed significant differences at level of one percentage in terms of responses to drought stress. Based on the obtained results from spraying of nano-particles at a concentration of 0.03 percent, the negative effects of drought stress were reduced and this treatment prevented from huge yield loss under stress.