Effects of zinc supply on Fusarium crown rot in wheat

A 4 site‐year experiment, conducted in the low precipitation zone of the inland Pacific Northwest region of the United States, was used to evaluate the effects of zinc (Zn) supply on Fusarium crown rot (FCR) in wheat ( Triticum aestivum L.). Treatments (0 or 5 lb Zn ac −1 ) were arranged in a randomized complete block design with four replications. Planting occurred in late September or early October, and Zn fertilizer was placed with the seed during planting. The plots were inoculated with Fusarium pseudograminearum . Plant samples were collected in April when the wheat was at Zadoks growth stage 31. Dry matter accumulation was estimated by weighing desiccated biomass, and tissue Zn concentration (TZC) was determined using a wet ash (acid digestion) method followed by inductively coupled plasma–atomic emission spectrometry. A postharvest FCR evaluation was conducted by examining stubble from 1 ft of row at an arbitrarily selected location in each plot. An ANOVA showed that the application of 5 lb Zn ac −1 increased Zn uptake and reduced FCR. The relationship between these two variables, during a year when FCR was prevalent, was best described by a nonlinear function that predicted a 13.7% decrease in FCR as TZC increased from 7 to 12 ppm.