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First study about mineral nutrition in 1918 Subsequently by Gericke in 1924 and
Ishizuka in 1932 Characteristics of various plant organ
greatly influence by environmental factor One of most important factor is mineral
nutrition
Element or simple inorganic compound ,indispensable for growth of crop and not synthesized by plant during normal metabolic process
16 essential element that need for plant
Categorized as major and minor element
• Major element :C,H,O,N,P,K,Ca,Mg,S,• Minor element :Fe,Mn,Cu,Zn,Mo,B,Cl• Each element has specific function• Some element only need for increase yield
and growth eg; Si• element must present in optimum amount
and as usable form
Most important nutrient element
Require in large amount
Highly demand in three stages of rice plant Early and mid tillering stage Panicle initiation stage Ripening stage
Give dark green appearance component of chlorophyll
Promote rapid growth involve in cell division
Increase plant height and tiller number
Increase size of leaves and grain
Effect to all three yield components Tillering stage: Increase number of panicle Panicle initiation stage :Increase spikelet
number per panicle Ripening stage: Increase filled spikelets %
in panicle Increase protein content of the grain
Involve in supply and transfer of energy for all the biochemical process
Important nutrient element in early stage of plant (at root initiation stage )
Stimulate root development
Promote earlier flowering and ripening
Encourage more active tillering
Promote good grain development and give high yield
Not constituent of any organic compound
Co factor for more than 40 enzymes
Basis of fertilizer recommendation
Increase fertilizer use efficiency
• Favours tillering
• Increase phosphorus response
• Transportation of assimilate within the plant
• Increase weight of the grain
• involve to control opening and closing of stomata
• Increase resistance to pest and disease
Connection with production of auxin
Activation of many enzymatic reaction
Close involvement in nitrogen metabolism
Cementing material of plant cell
Strengthen the cell wall
Maintain turgidity of cell wall
Promote root growth and development
• Constituent of chlorophyll molecules
• Component of several essential enzymes
• Strengthen cell wall
• Cementing material of plant cell
Constituent of the amino acids (cystine,cysteine)and plant hormones(thiamin,biotin)
Important to functioning of many plant enzymes,enzyme activators and oxidation reduction reaction
Relate to formation of chlorophyll
Possible catalyst in an organic form or combined with organic compound as component of redox enzymes
Factor in photosynthesis and in oxidation reduction process
Activator of several enzymes Oxidase Peroxidase Dehydrogenase Decarboxylase Kinase
• Catalyst in plant system
• Regulator of physiological function
–Nitrogen metabolism–Nutrient uptake–Calcium metabolism
Effect of normal growth of plant
Effect of water economy
Effect of disease and insect resistant
Effect on other nutrients
Growth stage Optimum level
Minimum level
N Tillering stage 2.9-4% <2.5%
Flowering stage 2.2-2.5% <2%
Mature stage 0.6-.8% _
P Tillering stage 0.2-0.4% <0.1%
Flowering stage 0.2-0.3% <0.18%
Mature stage 0.1-0.15% <0.06%
K Tillering stage 1.8-2.6% <1.5%
Flowering stage 1.4-2% <1.2%
Mature stage 1.5-2% <1.2%
S Tillering stage 0.15-0.3% <0.11%
Flowering stage 0.1-0.15% <0.1%
Mature stage - <0.06%
Growth stage Optimum level
Minimum level
Mg Tillering stage 0.15-0.3% <0.12%
Flowering stage 0.15-0.3% <0.13%
Mature stage 0.2-0.3% <0.1%
Ca Tillering stage 0.2-0.6% <0.15%
Flowering stage 0.3-0.6% <0.15%
Mature stage 0.3-0.5% <0.15%
Zn Tillering stage 25-30mg/Kg <20mg/Kg
Flowering stage 25-50mg/Kg <10mg/Kg
Mature stage -
Fe Tillering stage 75-150mg/Kg <70mg/Kg
Flowering stage 60-100mg/Kg <50mg/Kg
Mature stage -
Nutrient element Optimum level Minimum level
Nitrogen 0.25-1% <.25
Phosphorus 12-24 mg/Kg(acid soil)
<10 mg/Kg
24-36 mg/Kg( <10mg/Kg
Potassium 78-156 mg/Kg <78mg/Kg
Sulfur 10 mg/Kg <10mg/Kg
Magnesium >1cmmol/Kg <1cmmol/Kg
Calcium 3 cm mol/Kg <1cm mol /Kg
Silicon 40 mg/Kg <5 mg/Kg
Zinc 1-4 mg/Kg < 1mg/kg
Boron 0.5-1mg/Kg <0.5mg/Kg
Iron 5-10mg/Kg <5mg/Kg
Manganese 30-40mg/Kg <12mg/Kg
N, P, K, Zn most commonly apply by rice farmers as fertilizer
Sulfur occasionally apply to some soil- (NH4)2SO4,K2SO4,CaSO4
Other nutrient – air water soil plant residuals contaminant in commercial
fertilizer
low and improper levels of nutrient create nutrient deficiencies
Abnormally high mineral nutrient level cause to nutrient toxicities
Nutrient deficiencies and toxicity symptoms different for each element
In early stage ,have to identify symptoms
Occurs at critical growth stages (tillering and panicle initiation)
sometimes all leaves become light green and chlorotic at the tip
Older leaves or whole plants are yellowish
Leaves : narrow, short, erect, and lemon-yellowish green
The entire field may appear yellowish Reduced tillering, small leaves, and short
plants Grain number reduced Leaves die under severe N stress
Stunted dark green plants with erect leaves and reduced tillering
Leaves : narrow, short, very erect, and “dirty” dark green
Stems :thin and spindly and plant development retarded
Reduce the number of leaves, panicles, and grains per panicle
Young leaves appear healthy and older leaves turn brown and die
Maturity delayed (often by 1 week or more) In severe, stress plants not flowering
first on older leaves, then along the leaf edge, and finally on the leaf base
Upper leaves :short, droopy, and “dirty” dark green
Older leaves :change from yellow to brown
severe stress leaf tips turn to yellowish brown
Leaf tips and margins may dry up
Yellow stripes appear along leaf interveins and lower leaves become droopy
Rusty brown spots appear on the tips of older leaves and later spread over the whole leaf
Irregular necrotic spots occur on panicles
Lower leaves of stunted plants become droopy and dry with dusty brownspots
Symptoms appear 2–4 weeks after transplanting, with uneven plant growth
Under severe stress tillering decreases or stop
Time to crop maturity may increase
Increase spikelet sterility in rice
Midribs, near the leaf base of younger leaves, become chlorotic
Plant growth stunted and leaf blade size
reduced
In Sri Lankan soil sulfur some what deficient yellowing of the whole plant and chlorosis Mostly effect in vegetative stage Difficult to differentiate from N deficient No necrosis of lower leaves in N-deficient
plants Leaves become pale yellow in S-deficient
plants.
Orange-yellow interveinal chlorosis on older leaves.
plants become pale-colored interveinal chlorosis first appearing on older
leaves and later on younger leaves In severe cause Green coloring appears as a
“string of beads” In severe cases, chlorosis progresse to
yellowing and finally necrosis in older leaves
Chlorotic-necrotic split or rolled tips of younger leaves
Visible only under severe Ca deficiency The tips of the youngest leaves become
white (bleached), rolled, and curled Necrotic tissue develop along the lateral
margins of leaves, and old leaves turn brown and die
Interveinal yellowing and chlorosis of emerging leaves
Whole leaves become chlorotic and very pale
In severe cause entire plant becomes chlorotic and dies
decreased dry matter production, reduced chlorophyll concentration in leaves, and reduced activity of enzymes
Stunted plant with normal tiller number Intraveinal chlorosis on the leaves Chlorotic streaks spreading downward from
the tip to the base of leaves, which become dark brown and necrotic
Newly emerging leaves short ,narrow, and light green
Reduced plant height
Tips of emerging leaves become white
Growing point may die in severe cases
Bluish green leaves become chlorotic near the tip
Development of chlorosis downward along both sides of the midrib followed by dark brown necrosis of the tips
New leaves fail to unroll and maintain needle like appearance of entire leaf
Tiny brown spots on lower leaves starting from tips and spreading toward the bases
Leaf usually remain green
Severe cases the entire leaves become purplish brown
Orangish yellow interveinal chlorosisBecome necrotic in serious cases
Stunted plant and limited tilleringBrown spot on the veins of the leaf blade and leaf sheath,especially on the
lower leaves
Chlorosis at the tip of older leavesLarge dark brown elliptical spots in affected parts and ultimately turn brown and dry
up