Variations in yield and yield components by seed priming with three anti-gibberellin regulators on wheat cv. Azar-2

In this research, the effects of seed priming with three anti-gibberellin regulators were investigated on yield and yield components of wheat cv. Azar-2, based on randomized complete block design with three replications under regular irrigation conditions in research field of University of Zanjan, Zanjan, Iran, in 2012-2013. The experimental treatments were control (non-primed seeds), hydropriming, chlormequat chloride (400, 800, 1200 and 1600 μM), paclobutrazol (35, 70, 105 and 140 μM) and ancimidol (10, 20, 30 and 40 μM). The biological yield decreased in most treatments compared to control. On the other hand, seed priming with all of the growth retardants increased the grain yield. In contrast, the use of three growth retarder totally improved the grain yield of wheat cv. Azar-2. Among the growth regulators, paclobutrazol in 140, ancymidol in 20 and chlormequat chloride in 800 μM had the highest grain yield. Seed priming with mentioned growth retardants increased 1000-kernel weight compared to control. The highest fertile spike/m2 and seed/spike was found in 800 μM chlormequat chloride and 20 μM ancymidol, respectively. By increment in the number of fertile spikes, the length of spike decreased significantly. As a result, there are smaller spikes but with large grains in each plant. It seems that Azar-2 cultivar has a potential for increasing both the number of grain/spike and grain weight. Therefore, it is possible to increase grain yield in this cultivar by improving sink straight from both ways.