Micronutrients Gordon Johnson, Bill Raun, Hailin Zhang Department of Plant and Soil Sciences Oklahoma State University Gordon Johnson, Bill Raun, Hailin Zhang Department of Plant and Soil Sciences Oklahoma State University

The Nutrients: Concentrations in Soils and Plants (continued). Nutrient Soil (lb/a) Plant (ppm) Iron 14,000 – 1,100, Manganese 40 – 6, Copper Zinc Boron Chlorine 40 – 1, * - 1,000 Molybdenum Phosphorus ,000 3,000 Micronutrients

The Nutrients: Likelihood of crop deficiencies and common fertilizer. NutrientDeficiencyFertilizer Iron pH > 7.5; sorghum none Manganesenone- Coppernone- Zinc Pecans, corn (DTPA) Zinc Sulfate BoronPeanutsBorax ChlorineWheat* Molybdenumnone- Micronutrients

Leaf spotting showing Cl deficiencyCl treated

Soil testing for chloride. Mobile nutrient in soil. Mobile nutrient in soil.  Need 0-24” depth for accurate estimate of soil supply.  Amount required in soil should be related to yield goal. Mobile nutrient in soil. Mobile nutrient in soil.  Need 0-24” depth for accurate estimate of soil supply.  Amount required in soil should be related to yield goal.

Soil testing for chloride and sulfate. Results of 1999 soil test survey of S and Cl. Results of 1999 soil test survey of S and Cl.  Over 200 paired surface and subsoil samples.  17 counties.  Cl = 31 – 429.  S = Results of 1999 soil test survey of S and Cl. Results of 1999 soil test survey of S and Cl.  Over 200 paired surface and subsoil samples.  17 counties.  Cl = 31 – 429.  S =

Soil testing for chloride and sulfate; average values.

Distribution of chloride in surface and 24” soil layers.

Kansas State University chloride-winter wheat research. Test site soil Cl levels were 7, 7 and 15 lb/ac 0-24.” Test site soil Cl levels were 7, 7 and 15 lb/ac 0-24.” Yields ranged from 60 – 115 bu/acre. Yields ranged from 60 – 115 bu/acre. Response ranged from 0 to 15 bu/acre. Response ranged from 0 to 15 bu/acre. Test site soil Cl levels were 7, 7 and 15 lb/ac 0-24.” Test site soil Cl levels were 7, 7 and 15 lb/ac 0-24.” Yields ranged from 60 – 115 bu/acre. Yields ranged from 60 – 115 bu/acre. Response ranged from 0 to 15 bu/acre. Response ranged from 0 to 15 bu/acre.

Kansas State University chloride-winter wheat research. Response is variety specific. Response is variety specific.  Cimarron and Triumph 64 most sensitive.  Custer and Ogallala least responsive. Most varieties responded when soil test was low (< 20 lb/ac 0-24”). Most varieties responded when soil test was low (< 20 lb/ac 0-24”). Response is variety specific. Response is variety specific.  Cimarron and Triumph 64 most sensitive.  Custer and Ogallala least responsive. Most varieties responded when soil test was low (< 20 lb/ac 0-24”). Most varieties responded when soil test was low (< 20 lb/ac 0-24”).

Wheat response to Chloride at Carrier, OK.

Wheat response to Chloride at Hennessey, OK.

Wheat response to Chloride at Perkins, OK.

Other field observations on Cl. No wheat response to K addition as KCl for 30 years at Lahoma. No wheat response to K addition as KCl for 30 years at Lahoma. Magruder Plots. Magruder Plots. No wheat response to K addition as KCl for 30 years at Lahoma. No wheat response to K addition as KCl for 30 years at Lahoma. Magruder Plots. Magruder Plots.

OSU Magruder Plots: Influence of secondary and micronutrient input on crop production. Table 1. Chemical characterization (1992) and wheat grain yield of Magruder Plots. Units of measure: soil test P and K in lb/acre by Mehlich-3; yield in bushels/acre, average for period Treat.pH Soil Test-P Soil Test-K Yield Manure Check P NP NPK NPKL