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

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