The effect of hexaconazole, penconazole and calcium silicate on the quantitative and qualitative traits of two varieties of soybean under water deficit conditions

To study the different irrigation treatments on agronomic characteristics of soybean with and without use of triazoles and calcium silicate, an experiment was conducted as split-plot factorial in a randomized complete block design with three replications at the Research Field of Faculty of Agriculture, Tarbiat Modares University. The results showed that three-way interaction among experimental factors significantly influenced all traits, except plant height. Under non-stressed conditions for L17 and under moderate stress for Williams, hexaconazole spraying caused maximum and minimum protein yield with more than fourflods differences between them. Calcium silicate spraying on Williams under non- and moderate- stressed conditions, with 0.23 difference, showed most and least values of harvest index, respectively. Biological and seed yield under stress conditions decreased 9519 and 3328 kg/ha, respectively. According to the findings of these research, water deficit stress can cause reductions in values for quantitative traits and yield components of soybean, and under stress conditions, spraying admendatory materials can mitigate the harm of stress and increase the crop tolerance. Considering different response of soybean cultivars tested in terms of oil yield to spraying under varios conditions, it can be noted that penconazole and calcium silicate spraying on Williams under non-stressed conditions, and penconazole and hexaconazole spraying on L17 under moderate- and severe stressed conditions, exhibited higher efficiency in increasing oil yield.