PLANT PHYSIOLOGY. Az Agrármérnöki MSc szak tananyagfejlesztése TÁMOP /1/A

Transcription

1 PLANT PHYSIOLOGY Az Agrármérnöki MSc szak tananyagfejlesztése TÁMOP /1/A

2 Essential nutrients Nutrient deficiencies

3 Overview 1. Special techniques are used in nutritional studies 2. Essential nutrients 3. Mineral defficiencies 4. Soil, roots, and microbes

4 1. Special techniques are used in nutritional studies 1.1. Essential elements can be studied in plants grown under experimental conditions 1.2. The absence of certain elements reveals data about essentiality 1.3. Nutrient solutions containing only inorganic salts have been used in nutritional studies

5 Hydroponic growth system: plants are grown in nutrient solution fully saturated with oxygen Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 111.

6 Nutrient film technique Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 111.

7 Aeroponics: nutrient solution is sprayed on roots Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 111.

8 Ebb-and-flow system: roots are covered periodically with nutrient solution Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 111.

9 2. Essential nutrients 2.1. An essential element is defined as: - one that is intrinsic component in the structure or metabolism - whose absence causes several abnormalities in plant growth, development, or reproduction 2.2. They are classified according to their relative concentrations in plant tissues: macronutrients or micronutrients

10 Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 108.

11 3. Mineral defficiencies 3.1. Analysis of plant tissues reveals mineral deficiencies 3.2. Some essential elements can be recycled from older to younger leaves, others are relatively immobile 3.2. Inadequate supply of an essential element is manifested by characteristic deficiency symptoms

12 Relationship between yield (or growth) and the nutrient content of the plant tissue Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 117.

13 Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 113.

14 3. Mineral defficiencies 3.3. They can be grouped as: Group 1: Deficiencies in mineral nutrients that are part of carbon compounds (N, S) Group 2: Deficiencies in mineral nutrients that are important in energy storage or structural integrity (P, Si, B) Group 3: Deficiencies in mineral nutrients that remain in ionic form (K, Ca, Mg, Cl, Mn, Na) Group 4: Deficiencies in mineral nutrients that are involved in redox reactions (Fe, Zn, Cu, Ni, Mo)

15 Deficiency symptoms of nitrogen that is a constituent of many critical macromolecules Source: Taiz L., Zeiger E. (2010): Plant Physiology. Web material,

16 Deficiency symptoms of phosphorus that is part of the nucleic acid backbone and has a central function in intermediary Source:

17 Deficiency symptoms of potassium that activates enzymes and functions in osmoregulation Source: Taiz L., Zeiger E. (2010): Plant Physiology. Web material,

18 Deficiency symptoms of calcium that is important in cell division, cell adhesion, and as a second messenger Source:

19 Deficiency symptoms of magnesium that is a constituent of the chlorophyll molecule and an important regulator of enzyme reaction Source:

20 Deficiency symptoms of iron that is required for chlorophyll synthesis and electron transfer reactions Source: Taiz L., Zeiger E. (2010): Plant Physiology. Web material,

21 Deficiency symptoms of zinc that is an activator of numerous enzymes Source:

22 4. Soil, roots, and microbes 4.1. Negatively charged soil particles affect the adsorption of mineral nutrients 4.2. Soil ph affects nutrient availability 4.3. Excess mineral ions in the soil limit plant growth 4.4. To obtain nutrients from soil, plants develop extensive root system 4.5. Nutrient availability influences root growth

23 The principle of cation exchange on the surface of a soil particle Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 120.

24 Influence of soil ph on the availability of nutrient elements in organic soils Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 118.

25 Fibrous root systems of wheat (a monocot) Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 121.

26 Root biomass as a function of extractable soil NH 4+ and NO 3 - Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 124.

27 4. Soil, roots, and microbes 4.6. Mycorrhizal fungi facilitate nutrient uptake by roots 4.7. The fine hyphea of micorrhizae extend to reach of roots into the surrounding soil 4.8. In return, plants provide carbohydrates to the mycorrhizae 4.9. Symbiotic nitrogen fixation

28 Root infected with ectotrophic mycorrhizal fungi Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 125.

29 Association of vesicular-arbuscular mycorrhizal fungi with a section of a plant root Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 126.

30 Root nodules on a common bean (Phaseolus vulgaris) Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 352.

31 The infection process during nodule organogenesis that contains nitrogen fixing bacteria Source: Taiz L., Zeiger E. (2010): Plant Physiology. p. 356.

32 Summary Plants are autotrophic organisms capable of using the energy from sunlight to synthesize all their components from carbon dioxide, water, and mineral elements. Certain visual symptoms are diagnostic for deficiencies in specific nutrients in higher plants. The size of soil particles and the cation exchange capacity of the soil determine the extent to which a soil provides a reservoir for water and nutrients. To obtain nutrients from the soil, plants develop extensive root systems. Plant roots often form associations with mycorrhizal fungi. The fine hyphae of mycorrhizae extend the reach of roots into the surrounding soil and facilitate the acquisition of mineral elements.

33 Questions What does a plant need to grow from seed and complete its life cycle? What is an essential element? How many have been identified? What is a mineral deficiency? How can a mineral deficiency be recognized? How can farmers benefit from nutrient analysis? What is the importance of micorrhizal fungi?

34 THANK YOU FOR YOUR ATTENTION Next lecture: Nutrient uptake Solute transport Compiled by: Prof. Vince Ördög Dr. Zoltán Molnár