Evaluation of Zinc Fertilization for the Main Crops in Kansas Using New and Historic Data.

Zinc (Zn) deficiencies have become more frequent in recent years for the main crops in Kansas. This study involved two components and the objectives were to 1) review historic data from published papers since 1960 involving zinc fertilization in Kansas for corn, sorghum, wheat and soybean; and 2) evaluate soybean response to zinc on yield, seed Zn uptake, as well as soil and tissue parameters. The main database used for the review of historic data were the Kansas Fertilizer Research Reports, the ACSESS Digital Library, and the Kansas State Research Exchange. Results from this review indicated that most of studies involving Zn fertilization focused on corn, sorghum and wheat, with very limited information for soybean. Therefore, a new study was established in 2013 to generate data with focus on soybean. A Randomized Complete-Block Design with four replications was established at ten locations during 2013-2014.  Treatments consisted of an unfertilized control, micronutrient fertilizer as individual nutrient for Zn, and a combination of Zn, B, Cu, Mn and S using two different placements (broadcast and band). Soil samples were collected prior to planting and after harvest. Tissue samples were collected at R2-R3 stage. The review of historical data showed that zinc had significant effect on corn grain yield, and data for zinc in soybean was scarce. For the new study, Zn showed no significant difference over the control on soybean yield. However, significant differences were found in tissue and seed Zn concentration.