Molybdenum (Mo) deficiency occurs when plant growth is limited because the plant cannot take up sufficient quantities of this essential micronutrient from its growing medium. For crops growing in soil, this may be a result of low concentrations of Mo in the soil as a whole (i.e. the parent material of the soil is low in Mo), or because the soil Mo is held in forms that are not available to plants – sorption of Mo is strongest in acid soils.
In plants, Mo is essential for several enzymes including:
Molybdenum deficiency symptoms in most plants are associated with a build-up of nitrate in the affected plant part. This is a result of poor nitrate reductase activity. Symptoms include: [1] [2]
In legumes, inhibition of N2 fixation may lead to pale, yellowing, nitrogen-deficient plants. The size and number of root nodules are often reduced. [1]
Molybdenum deficiency is common in many different types of soil; some soils have low total Mo concentrations, and others have low plant-available Mo due to strong Mo sorption. Symptoms are most common where both conditions apply, such as in acid sandy soils. Molybdenum may be strongly sorbed in ironstone soils. Liming of soils frequently relieves Mo deficiency by decreasing Mo sorption. [2]
Molybdenum is an essential micronutrient which means it is essential for plant growth and development, but is required in very small quantities. Although Mo requirements vary among crops, Mo leaf concentrations (on a dry matter basis) in the range 0.2–2.0 mg kg−1 are adequate for most crops.
Raising the soil pH by liming frequently relieves Mo deficiency. In many situations, however, a soil-, seed- or foliar application of a Mo fertilizer is far more cost-effective than the use of lime to increase Mo availability. Sodium molybdate is a typical source of Mo. Typical soil and foliar application rates are 50–200 g Mo ha−1; recommended rates for seed treatment range from 7–100 g Mo ha−1. [1] Other sources recommend application levels of 0.25 kg/acre. [3]
Nitrogen fixation is a chemical process by which molecular nitrogen (N
2), which has a strong triple covalent bond, is converted into ammonia (NH
3) or related nitrogenous compounds, typically in soil or aquatic systems but also in industry. The nitrogen in air is molecular dinitrogen, a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms. Biological nitrogen fixation or diazotrophy is an important microbe-mediated process that converts dinitrogen (N2) gas to ammonia (NH3) using the nitrogenase protein complex (Nif).
A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced. For most modern agricultural practices, fertilization focuses on three main macro nutrients: nitrogen (N), phosphorus (P), and potassium (K) with occasional addition of supplements like rock flour for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment or hand-tool methods.
The chickpea or chick pea is an annual legume of the family Fabaceae, subfamily Faboideae. Its different types are variously known as gram or Bengal gram, chhana, chana, or channa, garbanzo or garbanzo bean, or Egyptian pea. Chickpea seeds are high in protein. It is one of the earliest cultivated legumes, and 9,500-year-old remains have been found in the Middle East.
A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excreted by cells to create non-cellular structures, such as hair, scales, feathers, or exoskeletons. Some nutrients can be metabolically converted to smaller molecules in the process of releasing energy, such as for carbohydrates, lipids, proteins, and fermentation products, leading to end-products of water and carbon dioxide. All organisms require water. Essential nutrients for animals are the energy sources, some of the amino acids that are combined to create proteins, a subset of fatty acids, vitamins and certain minerals. Plants require more diverse minerals absorbed through roots, plus carbon dioxide and oxygen absorbed through leaves. Fungi live on dead or living organic matter and meet nutrient needs from their host.
Boron deficiency is a common deficiency of the micronutrient boron in plants. It is the most widespread micronutrient deficiency around the world and causes large losses in crop production and crop quality. Boron deficiency affects vegetative and reproductive growth of plants, resulting in inhibition of cell expansion, death of meristem, and reduced fertility.
Calcium (Ca) deficiency is a plant disorder that can be caused by insufficient level of biologically available calcium in the growing medium, but is more frequently a product of low transpiration of the whole plant or more commonly the affected tissue. Plants are susceptible to such localized calcium deficiencies in low or non-transpiring tissues because calcium is not transported in the phloem. This may be due to water shortages, which slow the transportation of calcium to the plant, poor uptake of calcium through the stem, or too much nitrogen in the soil.
Iron (Fe) deficiency is a plant disorder also known as "lime-induced chlorosis". It can be confused with manganese deficiency. Soil iron concentration is high, but can become unavailable for absorption if soil pH is higher than 6.5. Excess of elements such as manganese in the soil can interfere with plant iron uptake triggering iron deficiency.
Nitrogen deficiency is a deficiency of nitrogen in plants. This can occur when organic matter with high carbon content, such as sawdust, is added to soil. Soil organisms use any nitrogen available to break down carbon sources, making nitrogen unavailable to plants. This is known as "robbing" the soil of nitrogen. All vegetables apart from nitrogen fixing legumes are prone to this disorder.
Potassium deficiency, also known as potash deficiency, is a plant disorder that is most common on light, sandy soils, because potassium ions (K+) are highly soluble and will easily leach from soils without colloids. Potassium deficiency is also common in chalky or peaty soils with a low clay content. It is also found on heavy clays with a poor structure.
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig’s law of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil.
Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place of nutrient application.
Micronutrients are essential dietary elements required by organisms in varying quantities throughout life to orchestrate a range of physiological functions to maintain health. Micronutrient requirements vary among organisms. Humans and other animals require numerous vitamins and dietary minerals. Plants tend not to require vitamins, but minerals are required still. For human nutrition, micronutrient requirements are in amounts generally less than 100 milligrams per day, whereas macronutrients are required in gram quantities daily.
Nitrate reductases are molybdoenzymes that reduce nitrate to nitrite. This reaction is critical for the production of protein in most crop plants, as nitrate is the predominant source of nitrogen in fertilized soils.
Zinc deficiency is defined either as insufficient zinc to meet the needs of the body, or as a serum zinc level below the normal range. However, since a decrease in the serum concentration is only detectable after long-term or severe depletion, serum zinc is not a reliable biomarker for zinc status. Common symptoms include increased rates of diarrhea. Zinc deficiency affects the skin and gastrointestinal tract; brain and central nervous system, immune, skeletal, and reproductive systems.
Micronutrient deficiency is defined as the sustained insufficient supply of vitamins and minerals needed for growth and development, as well as to maintain optimal health. Since some of these compounds are considered essentials, micronutrient deficiencies are often the result of an inadequate intake. However, it can also be associated to poor intestinal absorption, presence of certain chronic illnesses and elevated requirements.
William Albert Albrecht chairman of the Department of Soils at the University of Missouri, was the foremost authority on the relation of soil fertility to human health and earned four degrees from the University of Illinois at Urbana–Champaign. As emeritus professor of soils at the University of Missouri, he saw a direct link between soil quality, food quality and human health. He drew direct connections between poor quality forage crops, and ill health in livestock and from this developed a formula for ideal ratios of cations in the soil, the Base Cation Saturation Ratio. While he did not discover cation exchange in the soil as is sometimes supposed, he may have been the first to associate it with colloidal clay particles. He served as 1939 President of the Soil Science Society of America.
Twenty years before the phrase 'environmental concern' crept into the national consciousness, he was lecturing from coast to coast on the broad topic of agricultural ecology.
" The soil is the ‘creative material’ of most of the basic needs of life. Creation starts with a handful of dust.” Dr. William A. Abrecht.
Haifa Group is a private international corporation which primarily manufactures Potassium Nitrate for agriculture and industry, specialty plant nutrients and food phosphates. Haifa Group (Haifa) is the world pioneer in developing and supplying Potassium Nitrate and Specialty Plant Nutrients for advanced agriculture in various climates, weather, and soil conditions. Haifa also manufactures Controlled Release Fertilizers (CRF) for agriculture, horticulture, ornamentals, and turf. Many of Haifa's fertilizers can be used as a fertilizer solution that is applied through drip irrigation. This latter application is the principal driver of demand today, now that more countries are turning to controlled irrigation systems that make more efficient use of water.
Zinc deficiency occurs when plant growth is limited because the plant cannot take up sufficient quantities of this essential micronutrient from its growing medium. Zinc is one of the most important micronutrients.
Seventeen elements or nutrients are essential for plant growth and reproduction. They are carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), iron (Fe), boron (B), manganese (Mn), copper (Cu), zinc (Zn), molybdenum (Mo), nickel (Ni) and chlorine (Cl). Nutrients required for plants to complete their life cycle are considered essential nutrients. Nutrients that enhance the growth of plants but are not necessary to complete the plant's life cycle are considered non-essential. With the exception of carbon, hydrogen and oxygen, which are supplied by carbon dioxide and water, and nitrogen, provided through nitrogen fixation, the nutrients derive originally from the mineral component of the soil. The Law of the Minimum expresses that when the available form of a nutrient is not in enough proportion in the soil solution, then other nutrients cannot be taken up at an optimum rate by a plant. A particular nutrient ratio of the soil solution is thus mandatory for optimizing plant growth, a value which might differ from nutrient ratios calculated from plant composition.
Molybdenum is an essential element in most organisms. It is most notably present in nitrogenase which is an essential part of nitrogen fixation.
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