1. Essential Plant Nutrients
PLSC-250
Chapter 4

2. 17 Essential Plant Nutrients
Carbon, Hydrogen & Oxygen
Primary Nutrients ( N, P,K)
Secondary Nutrients (S, Mg, Ca)
Micro Nutrients(B, Mn, Cu, Zn,Fe, Mo, Cl, Ni)

3. CHO Carbon- Forms back bone of plants. Photosynthesis is key.
Hydrogen- Water transport
Oxygen-important is respiration.

4. Primary Nutrients Nitrogen Function-growth and green color
Deficiency- stunted growth, pale yellow older leaves
Absorbed N03-, NH4+

5. Primary Nutrients Phosphorous
Stimulates early growth and root formation, promotes seed production
Deficiency-slow growth, purplish color
Absorbed H2PO4-, HPO42-

6. Primary Nutrients Potassium
Function-improves resistance to disease & cold. Aids in CHO production
Deficiency-slow growth,scorched effect
Absorbed-K+

7. Secondary Nutrients Calcium
Function Aids in movement of CHO in terminal buds
Deficiency- Terminal bud dies, blooms shed early
Absorbed-Ca2+

8. Secondary Nutrients Magnesium
Function-ingredient of chlorophyll aids in translocation formation of oils and fats
Deficiency-yellowing of lower leaves curl up
Absorbed-Mg 2 +

9. Secondary Nutrients Sulfur
Function-aids in the formation of oils and certain proteins.
Deficiency-lower leaves yellow-green, stems and roots small.
Absorbed SO42-

10. Micronutrients Zinc ( zinc ion Zn++)
It controls the synthesis of indoleacetic acid, an important growth regulator.
Deficiency – Terminal growth areas are affected first. Citrus & other tree crops.
Symptoms – decrease in stem length & rosetting of terminal leaves, Reduced fruit buds, Mottled young leaves, Dieback of twigs after first year, Striping or banding on corn leaves.

11. Micronutrients Iron ( Fe++)
An activator for respiration, photosynthesis, and symbiotic nitrogen fixation.
Symptoms – Interveinal chlorosis of young leaves. Veins remain green except in severe cases., Twig dieback, In severe cases, death of entire limbs or plants.

12. Micronutrients Manganese (ion Mn++)
An activator for enzymes in plant growth.
Symptoms – Interveinal chlorosis of young leaves. Gradation of pale-green leaf coloration, with darker color next to veins., There is no sharp color distinction between veins & interveinal brown spots or streaks (barley) or necrotic spots (potatoes)

13. Micronutrients Copper (ions Cu+ & Cu++)
An activator of several plant enzymes & may play a role in Vitamin A production.
Symptoms – Stunted growth., Dieback of terminal shoots in trees., Poor pigmentation., Wilting & eventual death of leaf tips., Formation of gum pockets around central pith in citrus.

14. Micronutrients Boron (boric acid H3BO3)
Functions in plants in the differentiation of meristematic tissue.
Symptoms – Reduced flower or improper pollination., Death of terminal growth, causing lateral buds to develop, producing a “witch’s broom” effect., Thickened,, curled, wilted, & chlorotic leaves., Soft or necrotic spot in fruit or tubers

15. Micronutrients Molybdenum (molybdate ion MoO4=)
Need by plants to utilize nitrogen
Symptoms –Stunting & lack of vigor. This is similar to nitrogen deficiency, because of the key role molybdenum in nitrogen utilization., Marginal scorching & cupping or rolling of leaves., “Whiptail” of cauliflower., Yellow spotting of citrus.

16. Micronutrients Chlorine (ion Cl-)
Required for photosynthetic reaction in plants & regulating cell turgor potential.
Symptoms – Spotting of leaves of small grains, first on older leaves & more severe toward the tip half of the leaf blade., Delayed maturity.

17. Micronutrients Nickel (divalent cation Ni++)
Used in the conversion of urea to ammonia in plant tissue – overall nitrogen metabolism.
Symptoms – Chlorosis of young leaves., Death of meristem.