A brief introduction on plant nutrition and hydroponics

1. Di Liang Michigan State University Kellogg Biological Station A brief introduction on plant nutrition and hydroponics

2. Plants need the right combination of nutrients to live, grow and reproduce.

3. The major source of plant nutrition is the fixation of atmospheric CO2 into sugar. CO2 enters through the stomata.

4. Plants also need inorganic nutrients. • Macronutrients and Micronutrients Not sufficient?

5. Carbon, Hydrogen, Oxygen, Nitrogen, Potassium, Calcium, Phosphorus, Magnesium and Sulfur Each may exceed 1% dry weight of plant. Macronutrients

6. Iron, Chlorine, Copper, Manganese, Zinc, Molybdenum, and Boron Constitute from less than one, to several hundred PPM in most plants. Micronutrients

7. Functions

8. Functions

9. The Story of Boron

10. Plants will stop growing when a single nutrient is lacking although all other nutrients are sufficient. Leybig’s Law of the Minimum

11. General yellowing of older leaves (bottom of plant). The rest of the plant is often light green. N deficiency

12. N deficiency Corn: “V” shape on old leaves

13. Leaf tips look burnt, followed by older leaves turning a dark green or reddish-purple. P deficiency

14. P deficiency Rice: decreased tiller number, smaller ear, less fruits

15. P deficiency Citrus: thicker skin and lower quality

16. Older leaves may wilt, look scorched. Inter veinalchlorosis begins at the base, scorching inward from leaf margins. K deficiency

17. K deficiency Cotton: spots occurred between veins.

18. K deficiency Tomato: “green back”

19. K deficiency

20. New leaves (top of plant) are distorted or irregularly shaped. Causes blossom-end rot. Ca deficiency

21. Yellowing occurs between veins. “web” pattern is on old leaves. Mg deficiency

22. Mg deficiency

23. Too much fertilizer Easy to control Straightforward Why hydroponics

24. 6 ml of 1 M potassium nitrate 4 ml of 1 M calcium nitrate 1 ml of 1 M monoammonium phosphate 2 ml of 1 M magnesium sulfate 1 ml of micronutrient stock solution 1 to 5 ml of iron chelate stock solution Micronutrient stock solution per liter: 2.86 g boric acid 1.81 g manganese chloride - 4 hydrate 0.22 g zinc sulfate - 7 hydrate 0.08 g copper sulfate - 5 hydrate 0.02 g 85% molybdic acid True Hoagland Solution

25. Hydroponics

26. Roots -N +N

27. Thank you!