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Diagnosing Nutrient Deficiency in Wheat
Compiled By: Mohammad Safar NooriPh. D Scholar
Plant Nutritional Physiology Laboratory
Graduate School of Biosphere Science,
Hiroshima University, Japan
ContentsMacronutrients• Nitrogen• Phosphorous• Potassium
Intermediaries• Calcium • Magnesium• Sulfur
Micronutrients• Zinc• Manganese• Coper• Boron • Iron• Molybdenum
Macronutrients
Nitrogen
Role of Nutrient: Primary building block for all plant parts – leaves, shoots, roots, fruit buds, etc. Promotes rapid growth. Enhances nutrient uptake. Increases protein content in plants. Nitrogen combined with high concentrations of chlorophyll utilizes the sunlight
as an energy source to carryout essential plant functions including nutrient uptake.
Nitrogen Deficiency Symptoms
Slow growth and stunted plants Chlorosis (a yellowing) of the leaves starting from older ones due to the declining chlorophyll Starts with mature leaves - firing of tips and mid rib of foliage Tillering and leaf size are reduced in cereals. Excess nitrogen results in reduced quality and delayed colouration.
Factors Affecting Deficiency Additions of organic matter (manure, crop residues) will immobilize Nitrogen. Leaching of nitrate can move N out of the root zone. Soil moisture affects N in that too much results in saturated soils and denitrification, causing limited root
development and movement of soil water and thus nutrients. Excess ammonium also decreases the availability of Nitrogen to the plant. Toxicity symptoms include excessive shoot growth, large, succulent, dark green leaves, profuse flowering, poor
colour development, prolonged growth into fall and higher susceptibility of winter injury and leaf diseases. Heavy N fertilization intensifies copper and zinc deficiencies
Nitrogen Deficiency Symptoms
Phosphorus
Role of Nutrient: Stimulates early season growth. Grows deeper and stronger roots. Hastens plant maturity and promotes seed production. Phosphorus functions as one of the main promoters of photosynthesis,
nutrient transport, and energy transfer via energy-rich linkages (ATP). Phosphorus is involved in the formation of all oils, sugars and starches, and
encourages early plant growth for longer growing seasons. Phosphorus is utilized by plants to form nucleic acids, which regulates
protein synthesis.
•Phosphorus Deficiency Symptoms Slow growth and stunted plants Abnormal purplish colouration of foliage starting from older leaves Delayed maturity Poor grain, fruit and seed development Fruits and old leaves drop prematurely
Factors Affecting Deficiency Cold soil temperature, wet soils reduce the supply or conversion of available or labile P into the soil
solution. Low soil pH (< 6) and high soil pH (>7.2) reduce the availability of P to the plant. Higher available Fe and Ca in soil can limit P availability. Excessive phosphorus fertilizer can aggravate iron and zinc deficiencies and increase the soil salt content. Nitrogen fertilization may increase P concentration in plants by increasing root growth and by decreaing soil
pH as a result of the absorption of ammonium (NH4+) and thus increasing the solubility of fertilizer P.
Phosphorus Deficiency Symptoms
Potassium
Role of Nutrient: Promotes stalk strength and standability and improves resistance to
drought, disease and stress as it makes plant cells thicker. Potassium controls stomatal opening and closing, preventing
transpiration losses. Increases seed and grain quality by reducing the infected seeds. Regulates water status and activation of many enzymes Involved in the formation and translocation of sugars, proteins, starch,
and plant growth hormones.
Potassium Deficiency Symptoms
Tip and marginal leaf scorch - predominantly old mature foliage Interveinal chlorosis throughout the leaf Tendency to lodging - weak stalks in cereals Retarded root growth & reduction in yield Small and poorly coloured fruits, lacking flavour Wilted appearance under dry conditions
Factors Affecting Deficiency Dry weather, poor drainage and compaction are factors that inhibit root growth and therefore reduce the
availability of K. Plants require varying amounts of K at different growth stages, particularly at later growth stages. Magnesium, manganese, and calcium deficiencies become more pronounced with excess K. High levels of Ca and/or Mg can limit K uptake in some soils
Potassium Deficiency Symptoms
Tip and marginal leaf scorch - predominantly old mature foliage Interveinal chlorosis throughout the leaf Tendency to lodging - weak stalks in cereals Retarded root growth & reduction in yield Small and poorly coloured fruits, lacking flavour Wilted appearance under dry conditions
Factors Affecting Deficiency Dry weather, poor drainage and compaction are factors that inhibit root growth and therefore reduce
the availability of K. Plants require varying amounts of K at different growth stages, particularly at later growth stages. Magnesium, manganese, and calcium deficiencies become more pronounced with excess K. High levels of Ca and/or Mg can limit K uptake in some soils
Potassium Deficiency Symptoms
Intermediaries
Calcium
Role of Nutrient: Promotes stalk strength and standability. Stimulates root and leaf development. Improves disease resistance. Important in cell wall and membrane construction. Plays a vital role in Nitrogen metabolism. Critical for receptiveness of pollen and proper pollen tube development.
Calcium Deficiency Symptoms
Leaf margins irregular and foliage reflect spotted or chlorotic areas Deficiency visible in the storage tissues of fruit causes cells to collapse Failure of terminal growth and apical root tip development Distortion and reduced size of youngest leaves Due to the general immobility of Ca, the parts of the plants with low transpiration capacity, such as young leaves,
flowers and fruits are affected mostly by Ca deficiency.
Factors Affecting Deficiency In higher pH soils, Calcium forms a number of insoluble bonds rendering the Calcium fraction unavailable for
plant use (ie. Calcium Carbonate). Higher levels of Nitrogen can reduce the availability of Calcium. Presence of competing ions can also affect deficiency - calcium competes with other positively charged ions,
such as sodium (Na+), potassium (K+), and magnesium (Mg+2), and applying too much of these positively charged ions might decrease calcium uptake by plants.
High humidity
Calcium Deficiency Symptoms
Magnesium Role of Nutrient: An activator of more enzymes than any other nutrient, and plays key role in
chlorophyll production. Improves utilization and mobility of phosphorus and influences earliness
and uniformity of maturity. Essential for synthesis and the transport and storage of important plant
substances such as carbohydrates, proteins and fats. Involved in carbohydrate production and transportation. Involved in energy transfer and protein synthesis.
Magnesium Deficiency Symptoms Starts with interveinal chlorosis of older leaves Necrosis and red discoloration of stems occur during prolonged periods of deficiency Inadequate Mg will accentuate Phosphate deficiency Leaf curling upwards along margins Dropping foliage Reduced root growth Related to an imbalance of water, the entire plant looks wilted.
Factors Affecting Deficiency At pH values >6, magnesium is largely insoluble and therefore unavailable. Soils that are acidic and/or high in organic matter, highly leached soils with low CEC and calcareous soils and typically
affected by Magnesium deficiency. Excess levels of other cations such as K, Ca, and N can further restrict Mg availability. Higher amounts of exchangeable Mg than Ca will limit Ca availability. Low soil pH negatively affects the uptake of Mg by the plant. The uptake of Mg by the plant is negatively affected by large K, Mg and Ca, Mg ratios. This means that even at high
magnesium concentrations in the soil a latent or even severe deficiency of magnesium in plants is possible.
Magnesium Deficiency Symptoms
Sulphur
Role of Nutrient: Improves root growth and seed production. Promotes nodule formation on legumes. Required for synthesis of amino acids and proteins. When used with Nitrogen, Sulphur leads to improved protein &
milling quality. Sulphur helps with vigorous plant growth and resistance to cold.
Sulphur Deficiency Symptoms Yellow-green color, very similar in appearance to N deficiency Uniform chlorosis and yellowing on the younger leaves In canola, a cupping and/or reddish or purple colouration on the underside of the leaves Typical symptoms in oilseed rape are stunted growth, spoon-like arched leaves, pale yellow or white petals and
pods can appear bladder-like and bloated.Factors Affecting Deficiency Factors that will reduce S availability to the plant:
o Leaching of sulfateo Amount and type of soil colloids (higher clay = less availability)o Higher pHo Lower organic matter in soils
It is possible for sulphur to be temporarily fixed by microbial activity when they incorporate sulphur into fulvic acid and humic substances. Under anaerobic conditions, the sulphate-ion can be reduced by bacteria to hydrogen sulphide which is unavailable for plants.
The risk of sulphur deficiency is high on lighter soils, especially after heavy rain, on soils with a poor structure and under any conditions which result in a restricted root system. Excess sulphate reduces molybdenum uptake.
Sulphur Deficiency Symptoms
Zinc
Role of Nutrient: Aids plant growth hormones and enzyme systems. Helps in seed formation. Necessary for protein synthesis and membrane function. Influences plant hormone proteins, for example auxin development,
especially IAA. Active in chlorophyll synthesis & manufacturing of carbohydrates. Zinc causes healthy root growth, leading to enhanced grain yield
Micronutrients
Zinc Deficiency Symptoms
Leaves are smaller and narrower than normal (“little leaf”), and their tips are often white. The entire plant is often stunted (dwarfism)
Malformation of foliage and reduced fruit set Yellow or chlorotic striping Older and middle leaves display chlorotic spots with necrotic areas Shortened internode The growth of sprigs is inhibited and young shoots die Premature leaf senescence can also occur
Factors Affecting Zinc Deficiency:
Low organic matter soils, high pH soils, light and sandy soils. The pH and the total Zinc content of the soil. Excessive sulphate and phosphate content in the soil solution will result in
immobilization of zinc. Under anaerobic conditions, zinc can be precipitated into the barely soluble
sulphide form which is largely unavailable to plants. Conditions in which restrict root development such as compacted and cold wet
soils, will negatively affect Zinc availability. High available P can accentuate Zn deficiencies as well as high N fertilization and
very high potassium levels may also induce Zn deficiency.
Zinc Deficiency Symptoms
Manganese
Role of Nutrient: Regulates the splitting of the water molecules during photosynthesis Accelerates germination and early season seed development Activates several enzymes Increases the availability of P and Ca Aids in chlorophyll synthesis Heightens the concentration of valuable ingredients such as citric acid
and vitamin C
Manganese Deficiency Symptoms
Chlorosis on mature foliage followed by chlorosis on young foliage Crops become yellowish to olive green, and foliage appears wilted Interveinal chlorosis developing in leaves Gramineae show chlorotic and necrotic strips Acidification of soils with sulfur can correct manganese deficiency Limited mobility of Mn in the plant The deficiency symptoms are especially characteristic in oats which are called: grey speck or early blight; here
the plant exhibits dirty grey strips or spots on the base of the leaves The entire water balance is affected
Factors Affecting Deficiency High soil pH (7.0 or above) Soils that are high organic matter, cold wet soils, poorly drained soils, light sandy soils Low levels of K can also interfere with effective uptake of Mn. High soil levels of available copper (Cu), iron (Fe), or zinc (Zn) will reduce Mn uptake by plants.
Manganese Deficiency Symptoms
Copper
Role of Nutrient: Stimulates protein formulation Enhances N utilization Activates several enzymes Critical in the role of photosynthesis, protein and carbohydrate metabolism, and respiration. Has a significant influence on color development and regulates the photosynthetic electron
transport. Copper assists in the binding of free oxygen radicals which makes them harmless. Copper is important for lignification of cell walls.
• Copper is important for rhizobia production associated with legumes
Copper Deficiency Symptoms Young leaves become wilted with chlorosis and twisting, eventually they wither and die Heads may become deformed and fill poorly Higher incidence of stem melanosis and ergot in self-pollinating crops like wheat and barley In cereals, the youngest leaves turn white due to damaged chloroplasts
Factors Affecting Deficiency High soil pH, high organic matter, poorly drained and light sandy soils are all factors reducing
Cu availability. Excessive manure applications may bind copper to the additional organic matter, further
reducing availability. Increasing N impedes movement of Cu from older to newer tissue growth. High concentrations of available Mn, Fe, and P can depress copper absorption by plant roots
and may increase the intensity of copper deficiency.
Copper Deficiency Symptoms
Boron
Role of Nutrient: Essential for elongation of pollen tubes Promotes maturity Improves seed set Regulates metabolism of carbohydrates Facilitates the synthesis of nucleic acids Maintains cell wall integrity of roots to reduce beneficial root exudates Essential for cell division and development Aids in the use of nutrients and regulates other nutrients Aids production of sugar and carbohydrates, and is essential for seed and fruit development Boron enhances uptake of Ca, Mg, and K, and enables sugar translocation.
Boron Deficiency Symptoms Poor seed set or fruit set Causes breakdown of growing tip tissue Retardation of new growth, followed by death of younger leaves At B concentrations 12 ppm or less, terminal buds die and shoot dieback takes place Deficiency in alfalfa - yellowish to reddish yellow discolouration of the terminal foliage Breakdown of root crops such as beets and turnips, which develop corky dark discolorations Rhizobia development in the roots of legumes is inhibited
Factors Affecting Deficiency Low soil moisture Coarse textured, well drained, sandy soils and soils with low organic matter can all reduce Boron
availability. Soil with high organic matter will have greater availability of Boron. Soils with high levels of available Calcium may require additional applications of Boron. Boron deficiencies decrease the rate of water absorption, root growth, and translocation of sugars in
plants.
Boron Deficiency Symptoms
Iron
Iron serves as an activator for biochemical processes such as protein synthesis and forming of respiratory enzyme systems.
Iron is a component of many enzymes associated with energy transfer, nitrogen reduction and fixation, and lignin formation.
Because Iron (Fe) is immobile in the plant, deficiency symptoms appear on newly formed leaves or terminal growth.
Form used by plants: Fe+2 (ferrous) or Fe+3 (ferric). However, Fe+3 must be reduced to the ferrous form before uptake can occur.
Role of Nutrient: Promotes the formation of chlorophyll Acts as an oxygen carrier in respiration and photosynthesis Is an activator for biochemical processes Iron is an important part of the nitrogenase enzyme which effects N fixation in N fixing plants.
•Iron Deficiency Symptoms
Interveinal homogenous chlorosis of foliage, veins remain green, areas in between pale or almost white Stunted growth Deficiency shows up in terminal leaves Necrosis of tips and margins as deficiency progresses Can be mistaken for Mg deficiency
Factors Affecting Deficiency High soil pH Poor soil aeration Low organic matter, poorly drained, and/or compacted soils Alkaline soils (pH>7), or acidic sandy soils which also reduce Iron availability due to leaching and oxidation Soils receiving excessive amounts of irrigation water, especially in early spring Application of NO3- fertilizer may increase the chlorosis Deficiencies may also be induced by excess amounts of Cu, Mn, P, Na, Zn, or by a shortage of K.
Iron Deficiency Symptoms
Molybdenum Molybdenum is essential for the process of symbiotic nitrogen (N) fixation by Rhizobia bacteria in
legume crops. Molybdenum is needed by the plant in the synthesis and activation of nitrate reductase enzyme which
reduces nitrate to ammonium in the plant. Several materials supply Mo and can be mixed with NPK fertilizers applied as foliar sprays or used as a
seed treatment. Form used by plants: MoO4-2
Role of Nutrient: Optimizes plant growth Aids in the formation of legume nodules Converts nitrates (NO3) into amino acids and proteins within the plant. Involved in synthesis of ABA
Molybdenum Deficiency Symptoms The first symptoms of Mo deficiency is shown as a N deficiency, (yellow, yellow-green
or orange mottling of leaves followed by curling of leaf margins) because Mo is required for N fixation by leguminous plants.
Appears in older leaves first, and then in younger leaves until the growing point dies. Flowers wither or are suppressed, tissue has an abnormally low content of protein, total
soluble nitrogen and chlorophyll.
Factors Affecting Deficiency Soils below pH of 5.5 and low in Phosphorus will affect availability. Application of nutrients containing sulphates and ammonium N can negatively impact
Mo availability. Increase in P will increase Mo. Availability of Mo increases with soil pH. Soils derived from sands tend to be low in Mo.
Molybdenum Deficiency Symptoms
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