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Home , Atom, Atomic number, Calcium, Chemistry, Iron, Oxygen

Plants’ essential chemical elements

Every garden center and hardware Approximate composition of elements necessary for growth store sells guaranteed to “feed” . In a strict sense, we can’t feed plants. contains an source. Green plants capture solar energy and make their own food through ! Photosynthesis and other metabolic processes require chemical elements in appropriate doses for plants to survive and thrive. We can help, directly or indirectly, to provide plants these essential chemical elements. Back in 325 B.C., taught that all earthly things were composed of four elements: , , , and . That remained the dominant view for many centuries. In the and 1840s, -- such as the pioneering agricultural J. von Liebig -- hotly debated the question of “What do plants need to grow?” , mild , sunlight, and water were easy answers that roughly corresponded to Aristotle’s elements. But why did manure and compost tells us that virtually all provide natural fertility. increase growth? Was there some vital chemical elements were formed in the However, the contained in in organic that nurtured aftermath of the or in the is not directly taken up plants? thermonuclear heat of as they by plants. Through the , the This concept of was burn or explode. The essential elements A.B. Frank described the discredited by the new agricultural can vary widely in the quantities critical role of mycorrhizae in plant . They determined that required to support survival and , especially for trees. inorganic elements were growth. The relative amounts that are Mycorrhizae (Greek for “fungus- essential for plant . Their arguments needed can be compared by or ”) are symbiotic organs containing were so convincing that the concept of by the number of (table, above). plant roots and one or more species a vital life force became a discredited from a broad array of fungi. The plant superstition. could be Essential elements for growth. The feeds sugar to the fungus while the reduced to a recipe of sterile elements. elements in greatest abundance in fungus enhances the uptake of essential plants are the raw materials for elements -- particularly P and N. These Origin of elements. What is an photosynthesis. Photosynthesis uses beneficial infections may also increase element? Chemically, an element is a energy to split apart the resistance to drought and some plant pure substance composed of atoms that and of water and to split diseases. all have the same number of in apart the carbon and oxygen from This nutritional role of mycorrhizae the nucleus. That number is the taken from the and of free-living communities of “” and specifies the . Photosynthesis then fungi, , and other element’s in the . releases the oxygen from carbon microorganisms is sometimes hidden, The also contains dioxide back into the atmosphere and largely due to disruption of the natural . For each element, the sum of recombines the remaining elements to soil environment and through the numbers of protons and neutrons is form sugar. Sugar is the starting inhibition due to heavy applications of the approximate atomic weight. material for all processes in plants that chemical fertilizer -- particularly of P Depending on the definition, 16 out of require energy. Also, the bulk of a and N. These non-target consequences the 94 naturally occurring elements are plant is made of sugar (e.g. of common cultural practices in plant generally considered essential for the and starch) or compounds care are just beginning to get the depth growth of plants. Where do these derived from sugar (e.g. lignin). Soil and breadth of attention that they elements really come from, before they organic matter is largely cellulose and warrant. Ongoing research seeks to are bagged and boxed for sale? lignin which is critically important for identify what we can do to restore and retention, aeration, maintain these important relationships. mineral element storage, and to the Products and treatments continue to communities of soil that be developed to restore these communities of microorganisms that chlorosis and in older benefit plants. Although the treatment as as rosetting of lateral shoots. thresholds are not always known, the is required for target should be clear. Practices that photosynthesis, but in such low increase the natural ability of soil to quantities that deficiencies rarely cycle elements in a form available to occur. plants should be encouraged and Although present in plants in even situations or practices that disturb or smaller quantities, deficiencies diminish the processes such as low do occur, resulting in marginal scorch organic matter, heavy fertilization, soil of leaves, dead shoot tips, and compaction, and improper drainage deformation of fruits. should be discouraged. has a key role in the synthesis of , the site of photosynthesis What do essential elements do for within cells, as well as several critical the plant? is the element that respiratory . Deficiency of Fe is most associated with enhanced plant is extremely common in alkaline growth and is a key component of all due to impaired availability at high pH, . Many proteins as causing interveinal chlorosis and shoot enzymes or biological catalysts, dieback. making plant possible. is also required for Plants have very efficient pumps to synthesis and the release of take N from the soil, usually in the oxygen during photosynthesis. form of , and to bind it to sugar Deficiency of Mn causes chlorosis, fragments to form amino , the necrosis, and deformation of leaves. building blocks of proteins. Deficiency is a structural part of some in N decreases production of enzymes and a for others. chlorophyll and enzymes, resulting in Deficiency in Zn can reduce internodal decreased photosynthesis, decreased elongation and discolor the lower Healthy, -grown seedling is growth, and premature . to produce “bronzing”. showing extensive connections between is also critical for is a constituent of several roots and soil organic matter that photosynthesis, expansion, and to enzymes. Deficiencies of Cu can cause support soil microorganism diversity regulate the opening and closing of interveinal chlorosis, defoliation, leaf stomates. Deficiency of K to mottling, and shoot dieback. chlorosis and scorching of the leaf Although is the communities of microorganisms margins. essential element in the lowest sustains living communities of green interacts with pectin to in plants, Mo is still plants and especially trees. As plant crosslink plant cell walls and to act as a essential for the conversion of nitrate parts are shed and individuals die, the to regulate growth into amino acids in living cells. breakdown of organic matter as well as hormones. Woody stems contain an exudates from living plants fuel even greater proportion of Ca than is Plants as part of natural systems. communities of beneficial shown in the table, which is drawn In , plant nutrition is far from the microorganisms. from herbaceous plants. Calcium simple view of roots immersed in a Plant nutrition links the astrophysics deficiency reduces elongation of of inorganic chemicals. The of chemical elements to the utilization internodes and overall growth. importance of the living web of plant of solar energy of plants, the capture of A lies in the center nutrition is especially clear with trees carbon from and the release of oxygen of the chlorophyll and also and other perennial woody species that to the atmosphere, and the rich increases the effectiveness of some involve long-term relationships with diversity of soil microorganisms. Of enzymes. often communities of soil organisms course, urban and appears as chlorosis and scorching including fungi, bacteria, and protozoa. landscapes and the nurseries that serve between leaf and premature leaf All of these organisms, directly or them may feel the need to compromise shedding. indirectly, require organic matter in the part of the natural system to support Phosphorous is part of the soil to fuel their metabolism. As with short-term management needs. Still, “backbone” of nucleic acids that carry living roots, these organisms require plants did not develop in sterile genetic information. Phosphorous is the proper combination of air and water , but in living soil. also a key element in ATP, the primary in the soil for their own . molecule for the transfer of biological Soil compaction and adverse changes (Written by Dr. Kevin T. Smith, US energy. Deficiency in P causes severe in soil and drainage reduce Forest Service and originally published stunting and reduced flowering and the effectiveness of the microbial in American Nurseryman 206 (10): 10- fruiting. communities to support plant growth. 11, 2007). is a constituent of two The 19th century vitalists held a germ essential amino acids as well as plant of truth in the midst of their and cofactors. misunderstanding of plant nutrition. Deficiency of S causes on overall The life force in manure was exactly yellowing of younger leaves, and that. Life in diverse, interacting

(Essential elements, page 2)