Essential Plant Nutrients

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.