Essential Elements SOIL 5813 Soil-Plant Nutrient Cycling and Environmental Quality Department of Plant and Soil Sciences Oklahoma State University Stillwater, OK 74078 email: wrr@mail.pss.okstate.edu Tel: (405) 744-6414

Arnon's Criteria of Essentiality Element required to complete life cycle Deficiency can only be corrected by the ion in question Element needs to be directly involved in the nutrition of the plant and not indirectly via the need of another organism. Any mineral element that functions in plant metabolism, whether or not its action is specific (Tisdale et al., 1985) C, H, O, N, P, and S (constituent of proteins) Ca, Mg, K, Fe, Mn, Mo, Cu, B, Zn, Cl, Na, Co, V, Si (essential to one or more plants) 'CHOPKNS CaFe MgB Mn Cl CuZn Mo' MobileNutrients A.Plant 1. deficiency symptoms appear in the lower older leaves B. Soil Immobile Nutrients   A.Plant 1. deficiency symptoms appear in the upper younger leaves

Deficiency Symptom Element Mobility Mobility Form taken up Soil Plant by Plants ____________________________________________________________________________________ Overall chlorosis seen N Nitrogen Yes Yes NO3-,NO2-,NH4+ First on lower leaves Purple leaf margins P Phosphorus No Yes HPO4=,H2PO4-,H3PO4 Chlorotic leaf margins K Potassium No Yes K+ Uniform chlorosis, stunting S Sulfur Yes Yes(no) SO4=,SO2* (younger leaves) N*S interaction Stunting-no root elongation Ca Calcium No No Ca++ Interveinal chlorosis Fe Iron No (ls) No Fe+++,Fe++ (veins remain green) Interveinal chlorosis Mg Magnesium No (ls) Yes/No Mg++ Reduced terminal growth B Boron (NM) Yes No H3BO3° (chlorotic tips) Interveinal chlorosis Mn Manganese No No Mn++, Mn+++ Wilting, chlorosis Cl Chlorine Yes Yes Cl– reduced root growth Young leaves, yellow stunted Cu Copper No (ls) No Cu++ Interveinal chlorosis Zn Zinc No (ls) No Zn++ in young leaves  Interveinal chlorosis, stunting Mo Molybdenum Yes/No(ls) No MoO4= Dark green color Na Sodium No(ls) Yes Na+   C Carbon CO2 H Hydrogen H2O O Oxygen H2O * absorbed through plant leaves (NM) Non Metal (ls) Low Solubility Mo availability increases with soil pH, other micronutrients show the opposite of this. Immobile nutrients in plant; symptoms of deficiency show up in the younger leaves. Stage of growth when deficiency symptom is apparent = later stage

What are the Primary Nutrients needed by all crops Nitrogen (N) Potassium (K) Phosphorus (P) Soil (lb/a)* 400 – 8,000 800 - 60,000 400 – 10,000 Crop (lb/a)** 80 40 12 *Range of total amount in soil. From Chemical Equilibria in Soils. W.L.Lindsay, 1979. Wiley & Sons. **Calculated for 2 ton crop yield (67 bushel wheat).

Secondary Nutrients Needed by all Crops Calcium Magnesium Sulfur Soil (lb/a)* 14,000 – 1,000,000 1,200 - 12,000 60 – 20,000 Crop (lb/a)** 16 8 6 * Range of total in soil. From Chemical Equilibria in Soils. W.L.Lindsay, 1979. Wiley & Sons. **Calculated for 2 ton crop yield (67 bushel wheat).

Micronutrients Needed by all Crops Iron Manganese Copper Zinc Boron Chlorine Molybdenum Soil (lb/a)* 14,000 – 1,100,000 40 – 6,000 4 - 200 20 - 600 40 – 1,800 0.4 - 10 Crop (lb/a)** 1 0.8 0.08 0.6 4 0.0008 *Range of total in soils. From Chemical Equilibria in Soils. W.L.Lindsay, 1979. Wiley & Sons. **Calculated for 2 ton crop yield (67 bushel wheat).

Review: Nutrients Needed by all Crops Primary Nitrogen (N) Potassium (K) Phosphorus (P) Secondary Calcium (Ca) Magnesium (Mg) Sulfur (S) Micro Iron (Fe) Zinc (Zn) Manganese (Mn) Copper (Cu) Chlorine (Cl) Boron (B) Molybdenum (Mo)

Nutrients are grouped according to crop removal. Primary (N, P, K). Removed in largest amount by crop. Most commonly deficient. Secondary. Removed in moderate amount by crop. Micro. Removed in minute amount by crop.

Nutrients not found deficient in Oklahoma crops. Calcium. Liming prevents Ca deficiency. Manganese. Copper. Molybdenum.

Nutrients seldom found deficient in Oklahoma crops. Magnesium. Sulfur. Iron. Zinc. Boron. Chlorine.

Magnesium and Sulfur deficiencies. Occur on deep, sandy, low organic matter soils in high rainfall regions with high yielding forage production. Storage capacity for Mg and S is low. Large annual removal of nutrients.

Magnesium Deficiency in Alfalfa.

Sulfur Deficiency in Corn. Overall light green color, worse on new leaves during rapid growth.

Sulfur Deficiency in Wheat. Overall light green color, worse on new leaves during rapid growth.

Magnesium and Sulfur additions. Lime, especially dolomitic, adds Mg. Rainfall adds 6 lb/acre/yr of S. Like 120 lb of N (crop needs 1 lb S for every 20 lb N).

Iron deficiencies. Limited to high pH soils and sensitive crops. West-central and western Oklahoma. Grain sorghum, sorghum sudan, and wheat (also pin oak, blueberries and azaleas). Crop symptoms are chlorosis between veins of newest leaves.

Iron Deficiency in Corn. Note yellowing (chlorosis) between veins.

Iron Deficiency in Peanuts Note yellowing (chlorosis) between veins of newest leaves.

Correcting and Minimizing Iron Deficiency in Crops. Select tolerant varieties and crops. Incorporate several tons of rotted organic matter per acre of affected soil. Use a foliar spray of 1 % Fe as iron sulfate. Usually will require repeat spraying and will not be economical.

Zinc deficiencies. Usually found in high pH, low organic matter soils, and sensitive crops. Pecans, corn, soybeans and cotton. Crop symptoms are shortened internodes and bronze coloring.

Zinc Deficiency in Cotton (Mississippi)

Zinc Deficiency in Corn (Kansas). Note short internodes (stunted plants). Note “bronze” coloring of leaf.

Correcting Zinc Deficiency in Crops. Broadcast and incorporate 6 to 10 lb of Zn as zinc sulfate preplant. This rate should eliminate the deficiency for 3 to 4 years as compared to 1 to 2 lb applied annually. Foliar apply low rate to pecans annually.

Boron Deficiencies. Occasionally found in peanuts grown in sandy, low organic matter soils. Responsible for “hollow heart”.

Correcting Boron Deficiency in Crops. Apply ½ to 1 lb B according to soil test. May be applied as addition to N-P-K blend or foliar spray in-season. Excessive rates may kill crop. Applications may be needed each year.

Chlorine Deficiency. Occasionally found in wheat grown in sandy, low organic matter soils.

Chlorine Deficiencies. Symptoms are yellow “blotches’ on mature leaves.

Chlorine Deficiencies. Limited to areas where potassium (K) fertilizer is not used. K fertilizer is usually potassium chloride. Soil test Cl is < 20 lb/acre in top 2 feet.

Nutrients often Deficient in Oklahoma crops. Nitrogen (N). Legumes like soybeans and alfalfa get their N from microorganisms (rhizobium) that fix N from the atmosphere. Phosphorus (P). Potassium (K).

Nitrogen Deficiency. Shows up as chlorosis (yellowing) at the tip of the oldest leaf. Progresses toward the base of the leaf along the midrib (corn). Chlorosis continues to the next oldest leaf, after the oldest leaf becomes almost completely chlorotic, if deficiency continues.

Nitrogen Deficiency in Corn. chlorosis (yellowing) at the tip of the oldest leaf.

Nitrogen Deficiency in Corn. Chlorosis continues to the next oldest leaf

Potassium Deficiency. Common in crops grown in weathered soils developed under high rainfall. Symptoms are chlorosis at the tip of the oldest leaf (like N), that progresses toward the base along the leaf margins.

Potassium Deficiency. Common in crops grown in weathered soils developed under high rainfall.                                                                                                                        K Usually adequate K Usually deficient

Potassium Deficiency. Chlorosis at the tip of the oldest leaf progressing toward the base along the leaf margins (corn, alfalfa).

Phosphorus Deficiency. Deficiency in Oklahoma cultivated soils is related to historical use of P-fertilizers. P builds up in soils when high-P, low-N fertilizers are the only input. 10-20-10 and 18-46-0. Deficiency symptoms are purple coloring and some yellow on lower (oldest) leaves.

Phosphorus Deficiency. CORN purple coloring and sometimes yellow on lower (oldest) leaves.