Plant Nutrition

Slideshow Transcript

1. Slide 1: Chapter 37. Plant Nutrition AP Biology 2005-2006
2. Slide 2: Nutritional needs  Autotrophic does not mean autonomous  plants need…  sun as an energy source  inorganic compounds as raw materials  water (H2O)  CO2  minerals AP Biology
3. Slide 3: Macronutrients  Plants require these nutrients in relatively large amounts  C, O, H, N, P, K, Ca, Mg, S AP Biology
4. Slide 4: For what & from where? C synthesis CO2 O synthesis CO2 H synthesis H2O N protein & nucleic acid synthesis soil & fertilizer P nucleic acids, ATP, phospholipids soil & fertilizer K stomate control, water balance soil & fertilizer Ca cell wall & membrane structure, regulation soil Mg chlorophyll soil S proteins, enzymes soil AP Biology
5. Slide 5: Local Long Island soil issues Quartz silica based soils - low in P - can be acid Acid soils bind up mineral ions pH by adding lime AP Biology Granite
6. Slide 6: Micronutrients  Plants require in very small amounts  primarily cofactors AP Biology
7. Slide 7: Nutrient deficiencies  Lack of essential nutrients  exhibit specific symptoms  dependent on function of nutrient  dependent on solubility of nutrient AP Biology
8. Slide 8: Take 2 Magnesium deficiency fertilizer pellets & call me in the morning  Symptoms  chlorosis = yellowing of leaves  what is magnesium’s function? AP Biology
9. Slide 9: Chlorophyll Why does magnesium deficiency cause chlorosis? The chlorosis shows up in older leaves first, because plant moves Mg to newer leaves. Why? AP Biology
10. Slide 10: Water & mineral uptake  Water uptake  Cation uptake  plants cannot extract  cation uptake is aided by all water from soil, H+ secretion by root cells only free water (proton pump)  osmosis  active transport AP Biology
11. Slide 11: The role of soils  Plants are dependent on soil quality  texture / structure  relative amounts of various sizes of soil particles  composition  organic & inorganic chemical components  fertility AP Biology
12. Slide 12: So don’t rake Importance of organic matter your lawn or bag your leaves  Topsoil  most important to plant growth  rich in organic matter  humus  decomposing organic material  breakdown of dead organisms, feces, fallen leaves & other organic refuse by bacteria & fungi  improves soil texture  reservoir of minerals  organisms  1 tsp. of topsoil has ~5 billion bacteria living with fungi, algae, protists, insects, earthworms, nematodes AP Biology
13. Slide 13: Soil health as a global issue Not taking care of soil health has far-reaching, damaging consequences  1920’s Dust Bowl  lack of soil conservation  growing wheat  raising cattle  land exposed to wind erosion  drought AP Biology
14. Slide 14: Soil health as a global issue  Soil conservation & sustainable agriculture  maintaining healthy environment  production of food supply  economically viable farming industry “A sustainable agriculture does not deplete soils or people.” – Wendell Berry contour plowing cover crops crop rotation AP Biology
15. Slide 15: Global issues  fertility  erosion  irrigation  forestry destruction AP Biology
16. Slide 16: AP Biology
17. Slide 17: Fertilizers  “Organic” fertilizers  manure, compost, fishmeal  “Chemical” fertilizers  commercially manufactured  N-P-K (ex. 15-10-5)  15% nitrogen  10% phosphorus  5% potassium AP Biology
18. Slide 18: Nitrogen uptake  Nitrates  plants can only take up nitrate (NO3-)  Nitrogen cycle by bacteria  trace path of nitrogen fixation! root AP Biology What will the plant use N for?
19. Slide 19: Soybean root nodules  N fixation by Rhizobium bacteria  symbiotic relationship with bean family (legumes) AP Biology
20. Slide 20: Plow it under? Increasing soil fertility Why would you that?  Cover crops  growing a field of plants just to plow them under  usually a legume crop  taking care of soil’s health A man…  puts nitrogen back in soil outstanding in his field AP Biology erosion control, too
21. Slide 21: Some plant oddities… AP Biology 2005-2006
22. Slide 22: Parasitic plants  tap into host plant vascular system Indian pipe Mistletoe AP Biology
23. Slide 23: Plants of peat bogs  High acid environment  most minerals & nutrients bound up & are not available to plants  must find alternative sources of nutrients AP Biology
24. Slide 24: Carnivorous plants Sundew Venus fly trap Pitcher plant Are they really carnivores? AP Biology
25. Slide 25: AP Biology Pitcher plant
26. Slide 26: Uses of peat AP Biology
27. Slide 27: Any Questions?? AP Biology 2005-2006