Plant NutrientsAG-GH-PS-6

Why are nutrients important for plant

growth?

What are the three major macronutrients?

• Nitrogen• Phosphorus• Potassium

What are the three other major nutrients?

• Calcium• Magnesium• Sulfur

What are the seven micronutrients?• Iron• Manganese• Zinc• Boron• Copper• Molybdenum• Chlorine

What is the importance of nitrogen?

• Nitrogen is a vital component of most plant cell parts and is especially important in the creation of proteins during growth

• Helps the plant to recover from damages due to wind, animals, and cultivation.

• Helps to resist diseases and tolerates the effects of heat, cold, and drought.

What is the importance of nitrogen?

• Excess nitrogen can cause:• Dark green foliage• Weak tissues• Succulent vegetative growth• Delay in flowering and fruiting• Lower plant resistance to disease

What is the importance of nitrogen?

• A deficiency in nitrogen can cause:• Stunted growth• Pale green to yellow leaves that are

smaller than normal

What are some sources of nitrogen?

• Gradual decomposition of soil organic matter

• Fertilizer

What is the nitrogen cycle?

What is the importance of phosphorus?

• Storage and transport of energy in the plant

• Makes up nucleic acids and other important molecules

What is the importance of phosphorus?

• A deficiency of phosphorus can cause:• Altered metabolism and growth• Growth is stunted• Leaves are dark green and

sometimes distorted• Leaves and stems can turn red or

purple• Supply of phosphorus is limited to what

is already in the soil and what has been added. It must be monitored carefully.

What is the importance of potassium?

• Exact use is not known but it is theorized that potassium aids in regulation of stomatas and in general plant health• Deficiency symptoms include• Leaf chlorosis• Marginal scorch

• Although soil supply of potassium is high, it is usually not in a form usable by plants. Available potassium can range from 1-10%.

Advantages Disadvantages

Deficiency Symptoms

Nitrogen

• Constituent of amino acids

• Constituent of chlorophyll

• Stimulates use of carbohydrates

• Stimulates root growth and development

• Regulates uptake and use of other nutrients

• Too much can burn the plant

• Activates enzymes

• Regulates opening and closing of stomata

• Stunted growth

• Small, pale, yellow leaves

Advantages Disadvantages

Deficiency Symptoms

Phosphorus

• Component of DNA & RNA

• Affects cell division, root development, maturation, flowering and fruiting, and overall crop quality

• Component of high-energy bonds in plant cells, necessary for release of energy for plant processes

• Deficiency can reduce growth

• Cause dark to reddish leaf colorations

• Purpling of the stem, leaf, or veins in the underside of the leaf

• Altered metabolism and growth

• Dark green leaves

Advantages Disadvantages

Deficiency Symptoms

Potassium

• Activates enzymes

• Regulates opening and closing of stomata

• Regulates water uptake by root cells

• Essential for photosynthesis, starch formulation, and translocation of sugars

• Cause increased respiration & transpiration

• Reduce environmental stress tolerance

• Increase disease and reduce growth

• Burn or scorch of margins of leaves, particularly older leaves

What is the pH scale? How does it work?

• The pH is used to measure the amount of alkalinity or acidity in the soil

• The scale is based on the hydrogen ion concentration in the soil

• The soil has many different chemical reactions that take place

What is the pH scale? How does it work?

• The degree of acidity or alkalinity of the soil controls the availability of nutrients to the plants that inhabit it

• Plants have a certain pH that they need in order to prosper to their full potential

What are examples of acids and bases?

The pH Range Most Suitable for Some Plants

pH 4.5 – 5.5Strong Acid

pH 5.5 – 6.0Medium Acid

pH 6.0 – 6.5Moderate Acid to Slight

Acid

pH 6.5 – 7.5Slight Acid to Slight

Alkaline

• Azaleas

• Camellias

• Irish potato

• Watermelon

• Bermuda grass

• Fescue, tall

• Hollies

• Kudzu

• Peaches

• Pecans

• Sweet potatoes

• Strawberries

• Apples

• Cantaloupes

• Kentucky bluegrass

• Lespedeza

• Lima beans

• Peanuts

• Peas

• Pepper

• Sweet corn

• Tomatoes

• Turnips

• Cabbage

• Spinach

• Pyracanthea

The relationship of plant growth to the pH scale

Multiple choice, select the best answer. 

1. Which of the following is not a major macronutrient?A. PhosphorusB. MagnesiumC. PotassiumD. Nitrogen

 2. Lack of nitrogen, or nitrogen deficiency will cause:

A. Purple or red leavesB. Pale green to yellow leaves that are smaller than normalC. Marginal scorchD. Extreme root growth 

3. Which is not a direct source or nitrogen to the plant in the nitrogen cycle?A. Animal wasteB. Soil nitrogenC. Atmospheric nitrogenD. Nitrogen in rain water

 4. Which is not true of the pH scale?

A. The scale is based on hydrogen ion concentrationB. pH measures the acidity of soilC. Plants require certain pHs to reach maximum growthD. The scale is based on hydroxide ion concentration