Bio Huma Netics, Inc.

Micronutrients Are the Key to Better Yields

Issue link:

Contents of this Issue


Page 1 of 12

2 Micronutrients Key to Better Yields 800.961.1220 • Acid leaching can remove micronutrients from the soil, as can intensive cropping—in which large amounts of plant nutrients are removed in the harvest. • Excessive use of phosphate fertilizers can diminish the availability of some micronutrients, particularly iron and zinc. • Extremes in soil pH can result in reduced micronutrient availability (Figure 1) or even cause micronutrient toxicity. Most plants have a pH range "sweet spot" in which the micronutrients in the soil are soluble enough to satisfy plant needs without becoming so soluble as to become toxic. • Soils very low or very high in organic matter or with sandy texture or heavy clay can result in micronutrient imbalance. • Soil erosion can carry away humus and organic matter in which some micronutrients are held. • Cold, wet soils can result in slowing or stopping plant root development; thus, roots explore smaller areas and take in an insufficient amount of micronutrients. Because micronutrients are required in very small amounts for adequate nutrition, the range between "enough" micronutrient and "too much" micronutrient can be a lot more narrow than for macronutrients. Micronutrient toxicities that occur can damage or retard plant growth and affect yield. Toxicities rarely result from over-fertilization: they are more commonly associated with contaminations such as from concentrated wastewater, waste sludges being continuously applied, or from the excessive application of copper- or zinc-containing fungicides. Contaminated irrigation water can also be a source of micronutrient toxicity. Common Micronutrient Deficiencies It is beyond the scope of this article to list all the possible types of micronutrient deficiencies and their characteristic symptoms. Information, photos, and tables of deficiency factors are available from multiple online sources. However, some crops and soil types are more prone to certain types of micronutrient deficiency than others: examples include boron deficiency in alfalfa; copper deficiency in wheat, corn, and soybeans; nickel deficiency in pecans; and molybdenum deficiency in soybeans. Zinc deficiencies frequently occur on calcareous, high-pH, sandy texture, high phosphorus, and eroded soils. Poorly drained soils may also be deficient. Some of the more common symptoms to look for include stunted growth; delayed maturation; yellowing and wilted Figure 1. Available Macro- and Micronutrients in Relation to Soil pH. Macronutrients Micronutrients 5.0 6.0 7.0 8.0 9.0 10.0 4.5 9.5 8.5 7.5 6.5 5.5 4.0 5.0 6.0 7.0 8.0 9.0 10.0 4.5 9.5 8.5 7.5 6.5 5.5 4.0 5.0 6.0 10.0 4.5 6.5 5.5 4.0 7.0 7.5 8.0 8.5 9.0 9.5 NITROGEN PHOSPHORUS POTASSIUM SULPHUR CALCIUM MAGNESIUM IRON MANGANESE COPPER & ZINC BORON MOLYBDENUM Modied from Truog E. (1947). Soil reaction inuence on availability of plant nutrients. Soil Science Society Proceedings of 1946. 11-C, 305308. Strongly Acidic Medium Acidic Slightly Acidic Neutral Strongly Alkaline Medium Alkaline Slightly Alkaline pH S U S T A I N A B L E SOIL FERTILITY O P T I M A L GROWTH MANAGEMENT U L T R A - E F F I C I E N T CROP NUTRITION Z E R O - R E S I D U E CROP PROTECTION V E R S A T I L E SPECIALTY PRODUCTS C A R B O N - R I C H ORGANIC ACIDS FOR A HUMA GRO ® oers a COMPLETE LINE of 50+ innovative, highly flexible liquid inputs that allow you to get more from your crop than ever before! LOOKING FOR ? PRODUCTS MADE IN U.S.A. Powered by

Articles in this issue

Links on this page

view archives of Bio Huma Netics, Inc. - Micronutrients Are the Key to Better Yields