Managing Plant Nutrients

17 essential mineral nutrients

1. Boron - BO₃^3-

2. Calcium - Ca²⁺

3. Carbon

4. Chlorine - Cl^-

5. Copper - Cu²⁺

6. Hydrogen

7. Iron - Fe²⁺, Fe³⁺, heme

8. Magnesium - Mg²⁺

9. Manganese - Mn²⁺

10. Molybdenum - Mo³⁺

11. Nickel - Ni²⁺

12. Nitrogen - NO₃^-, NO₂^-, NH₄⁺

13. Oxygen

14. Phosphorus - PO₄^3-, P₂O₇^4-

15. Potassium - K⁺

16. Sulfur - SO₄^2-, SO₃^2-, SH^-

17. Zinc - Zn²⁺

Plant mineral nutrients are in the charged (___) form of the element

ion

True or false. Some plant mineral nutrients have one or more different charges and chemical forms.

True

Plant cell walls are ______

porous

Water and nutrient ions can flow nearly unimpeded into the ____ and the flow continues as far as the endodermis

root

____ ____ are the site of water and ion entry into the plant

Root hairs

Nutrient ions can also be taken into the plant root through exchange with ____ ________, and through symbiotic relationships with microorganisms

soil particles

What are negatively charged nutrients?

Anions

Anions are _______ by negatively charged soil particles

repelled

2 examples of anions

1. Nitrate (NO⁻³)

2. Chloride (Cl^-)

What are positively charged nutrients?

Cations

Cations _______ to negatively charged soil particles

adhere

_______ may be exchanged with cations or H⁺ bond to root or in soil solution

Cations

Once in the endodermis, nutrients are imported into __________ cell

endodermal

Once in _____ cells, the nutrient is transported up to other plant organs

xylem

The main control point for mineral transport into the plant is the ________________

plasmalemma

The plasmalemma is a _____ bilayer that is mostly impermeable to water and ions

lipid

________ in the plasmalemma membrane act as selective channels

Proteins

Mycorrhizae infections are composed of hyphae (small tubular filaments) that form an ___________ with plants

association

Mycorrhizae infection: fungal hyphae are finer than _____ and extend further into soil pores than root hairs aiding in nutrient absorption

roots

What % of dicots have mycorrhizal associations?

83%

What % of monocots have mycorrhizal associations?

79%

Plant bacterium _________ relationship that is specific to plant species

symbiotic

Plants respond to specific soil bacteria (rhizobia) in a symbiotic relationship by forming _______ to house bacteria

nodules

In a symbiotic relationship between a plant and bacteria, the plant supplies the bacterium with __________ food

carbohydrate

In a symbiotic relationship between a plant and bacteria, the bacteria supplies the plant with a useable form of _________

nitrogen

3 primary macronutrients

1. Nitrogen

2. Phosphorus

3. Potassium

3 secondary macronutrients

1. Calcium

2. Magnesium

3. Sulfur

8 macronutrients

1. Boron

2. Chlorine

3. Copper

4. Iron

5. Manganese

6. Molybdenum

7. Nickel

8. Zinc

Plant mineral nutrients are governed by the “law of ________”, meaning that the nutrient in the least supply dicates plant growth

minimum

6 most limiting mineral nutrients (in order of most to least limiting)

1. Nitrogen

2. Phosphorus

3. Potassium

4. Magnesium

5. Calcium

6. Iron

Which nutrient is the most required of all macro and micronutrients?

Nitrogen

Which nutrient is known as the most limiting element?

Nitrogen

Which limiting element is…

• part of amino acids, proteins, and enzymes

• nucleosides, nucleotides, and nucleic acids

• constituent of the chlorophyll molecule

• synthesis of phytohormones

Nitrogen

What is the sufficiency range of Nitrogen?

1.0 - 6.0%

Which nutrient has a sufficiency range of 1.0 - 6.0%?

Nitrogen

2 most common forms of Nitrogen in the soil

1. NO₃^- (grows the plant)

2. NH₄⁺ (greens the plant)

NH₄⁺ (form of Nitrogen) is held by _________

colloids

NO₃^- (form of Nitrogen) is ______ leachable from soils?

highly

Nitrogen is most available at pH # to #

6.0 to 8.0

Are all forms of Nitrogen mobile or immobile in plants?

mobile, so deficinecy starts at base

Important points in the Nitrogen cycle are where Nitrogen is ____ ________ and where it can be ____

• crop available

• lost

Urea-based, ammonium-based, nitrate-based, and organic are all _________ fertilizers

Nitrogen

NO₃^- _____ the plant

grows

NH₄⁺ ______ the plant

greens

Which form of Nitrogen is usually found in higher concentrations than the other?NH₄⁺ or NO₃^-?

NO₃^-

Ideally, there should be a # : 1 ratio of NO₃^- : NH₄⁺ in soils

3:1

Which nutrient has the following deficiency symptoms?

• plants appear weak and stunted

• small leaves with light green to yellow color

• uniform yellowing

  • older leaves to younger leaves

• older leaves may fall prematurely

• photosynthesis is significantly reduced

• reduced cytokinin production

  • rapid shift towards senescence

Nitrogen

Which limiting element…

• is a component of enzymes and proteins

• is a component of ATP, RNA, and DNA

• buffers cellular pH changes

Phosphorus

What is the sufficiency range of Phosphorus?

0.2 - 0.5%

Which limiting element has a sufficiency range of 0.2 - 0.5%?

Phosphorus

2 forms of Phosphorus in soil

1. PO₄^3-

2. P₂O₇^4-

The majority of phosphorus in soil is __________ to plants

unavailable

Is Phosphorus mobile or immobile in plants?

mobile, so deficiency starts at base

Phosphorus is mostly available at the slightly acidic to neutral pH range (## - ##)

5.5 - 7.0

Identify which nutrient is deficient

Nitrogen

Identify which nutrient is deficient

Phosphorus

Which nutrient has the following deficiency symptoms?

• Purple/reddish coloration

• Slows and retards growth of roots and shoots, stunting the plant

• Redding or purple color on lower leaves

Phosphorus

Phosphorus deficiency symptoms occur when it falls below ## %?

0.2%

Low soil ______ can cause a Phosphorus deficiency

temps

True or false. Phosphorus is held tightly in the soil.

True

Which nutrient has high potential to be carried in runoff and erosion?

Phosphorus

Which nutrient is the most limiting nutrient for aquatic plant growth?

Phosphorus

Phosphorus is important for ____ growth

root

“Starter fertilizers” are high in soluble forms of which nutrient?

Phosphorus

Which limiting element…

• essential in maintaining water status

  • controls turgor pressure & opening / closing the stomata

• required for carb transport

• involved in cellulose synthesis

Potassium (K)

What is the sufficiency range of Potassium (K)?

1.5 - 4.0%

Which limiting nutrient has a sufficiency range of 1.5 - 4.0%?

Potassium (K)

Less than #% of soil Potassium is avaible, while 90 - 98% is tied up

2%

Identify the nutrient deficiency

Potassium (K)

Which nutrient has the following deficiency symptoms?

• plants easily lodge or fall over (reduce lignification)

• yellow color around edges of older leaves

• leaves appear to be “burned” around edges

• droopy, flaccid leaves due to loss of water status

• symptoms appear on older leaves first

Potassium (K)

Is Potassium (K) mobile or immobile in plants?

mobile, so deficiency starts at base

Potassium (K) increases plant ______ and quality

vigor

Potassium (K) application is needed on ______ soils

sandy

Which limiting element…

• binds cell wall pection for structural role

• is involved in cell elongaation and division

• regulates cellular anion levels

• enhances pollen tube germination

• helps in protein synthesis and carb transfer

Calcium (Ca)

High levels of Calcium (Ca) in soil may interfere with which other 4 nutrients?

1. Potassium (K)

2. Iron (Fe)

3. Magnesium (Mg)

4. Boron (B)

Calcium (Ca) is taken up by plants ________

passively

Because Calcium (Ca) is taken up by plants passvely, plant uptake is highly dependent on adequate _____ supply to plant roots

water

Calcium (Ca) availability in soil depends on ___

pH

At pH above 7.0, Calcium (Ca) readily reacts with _________, rendering both relatively unavailable to plants

phosphate

Which nutrient has the following deficiency symptoms?

• growing points of leaves and roots turn brown and die

• young leaves become chlorotic and deformed, eventually leading to marginal necrosis

• fruit/flower quality is reduced

Calcium (Ca)

Is Calcium (Ca) mobile or immobile in plants?

immobile, so deficiency starts at top

Which limiting element…

• is found in center of tetrapyrrole ring of chlorophyll molecule

• catalyzes the transfer of phosphoryl groups between ATP and ADP

• cofactor for kinase enzymes

• neutralizes anions in thylakoid membrane

• stabilizes ribosomes during protein synthesis

Magnesium (Mg)

What is the sufficiency range of Magnesium (Mg) in plants?

0.15 - 0.4%

Which limiting nutrient has a sufficiency range of 0.15 - 0.4% in plants?

Magnesium (Mg)

Identify the nutrient deficiency

Calcium (Ca)

Magnesium (Mg) availability in soil depends on the soil’s ___

pH

In mineral soils, exchangeable Magnesium (Mg) is most available at pH ## - ##

6.5 - 8.5

Mg is not held to soil CEC sites tightly so exchangeable Magnesium (Mg) can _____

leach

Excess K, NH₄, Ca, and Al can lead to ___________ deficiencies

Magnesium (Mg)

________ stimulates Magnesium (Mg) uptake

Nitrate (NO₃^-)

Identify the nutrient deficiency

Magnesium (Mg)

Which nutrient has the following deficiency symptoms?

• yellowing and interveinal chlorosis of older leaves

• margins of younger leaves become necrotic

• green conductive tissue surrounded by yellow background

Magnesium (Mg)

Is Magnesium (Mg) mobile or immobile in plants?

mobile, so deficiency starts at base

Magnesium uptake declines rapidly at a pH less than ##

5.5

Which limiting nutrient…

• has a role in oxidation-reduction, electron transfer

• is involved in chlorophyll synthesis

• is a component of cytochromes of PS I and II

• is a component of ferridoxin

• is required for NO₃^- and SO₄^2- reduction

• is needed for N₂ assimilation

• is needed for energy production (NADP)

Iron (Fe)

2 most common forms on Iron (Fe) in soil

1. Fe³⁺ (Ferric)

2. Fe²⁺ (Ferrous)

Which form of Iron (Fe) dominates in soil? Fe³⁺ (Ferric) or Fe²⁺ (Ferrous)?

Fe³⁺ (Ferric)

Which form of Iron (Fe) is the physiologically active form? Fe³⁺ (Ferric) or Fe²⁺ (Ferrous)?

Fe²⁺ (Ferrous)

As pH increases, Iron (Fe) intake ________

decreases