Report mineral nutrition
description
Transcript of Report mineral nutrition
Mineral NutritionExperiment 4
INTRODUCTION
Introductory Concepts
• Plant nutrition –Organic nutrition - focuses on the
production of carbon compounds
–Inorganic nutrition - concerned with the acquisition of mineral elements from the soil
Introductory Concepts
• Nutrient–A substance needed to survive or
necessary for the synthesis of organic compounds
• Mineral – inorganic elements which come from the
soil and are dissolved in water and absorbed through the roots of the plants
Introductory Concepts
• Mineral Nutrient–may be toxic to plants–may play no role in metabolism–may be essential for plant growth
• A mineral nutrient is regarded as essential if, in its absence, a plant cannot complete its life cycle.
Introductory Concepts
• Essential Elements (essential mineral nutrients)1. one whose absence prevents a
plant from completing its life cycle
2. one that has a clear physiological role
Introductory Concepts
• Classification of Essential Elements–Based on their abundance in plants
1. Micronutrients
2. Macronutrients Nitrogen Phosphorus Potassium Calcium, Magesium, Sulfur, Silicon
Introductory Concepts
• Nutrient Deficiency–concentration of a nutrient decreases
below the typical range– lead to specific visual, often
characteristic, symptoms reflective of the role of that particular nutrient in plant metabolism
Objectives
1. To become familiar with the method of growing plants by hydroponics
2. To observe deficiency symptoms associated with inadequate supplies of selected essential element
METHODOLOGY
one -week old Zea mays
5 set-ups of amber bottle
with solutions
Observe for 3 weeks
Stock Solution
1Complete
2-N
3-P
4-K
5Distilled
H2O
1 M Ca(NO3)2 5 mL - 5 mL - -
1 M KNO3 5 mL - 5 mL - -
1 M MgSO4 2 mL 2 mL 2 mL 2 mL -
1 M KH2PO4 1 mL 1 mL - - -
FeEDTA 2 mL 2 mL 2 mL 2 mL -
Micronutrients 1 mL 1 mL 1 mL 1 mL -
1 M NaNO3 - - - 5 mL -
1 M NaH2PO4 - - - 1 mL -
1 M CaCl2 - 5 mL - - -
1 M KCl - 5 mL 1 mL - -
Other procedures
• Get initial and final length of root and shoot• Regularly aerate each set-ups• Regularly change the stock solutions in each
set-up
Sample set-up
Hydroponics5 set ups: 1 – complete; 2 – minus K; 3 – minus N; 4 – minus P; and 5 – distilled water
Zea mays seedlings
15 seedlings grouped into 5 according to height and age
RESULTS
Growth of Seedlings in Different Nutrient Solutions
Treatment
Average Initial length (cm)
Average Final length (cm)
Root Shoot Ratio Root Shoot Ratio
Complete 5.0 17.6 0.28 9.8 46.9 0.22
Minus N 9.0 19.0 0.47 9.1 36.5 0.25
Minus P 11.0 16.2 0.67 13.4 19.0 0.71
Minus K 6.5 17.5 0.37 7.2 19.2 0.38
Distilled H2O
11.5 18.0 0.63 43.1 29.6 1.45
Observations in each set-up
• Complete–Short roots but high amounts of lateral
roots–Good shoot growth–Lively green leaves–Minor chlorosis at leaf tips–Generally healthy
Observations in each set-up
• Minus Nitrogen–Very poor shoot growth–Interveinal Chlorosis–Violet leaf sheaths
Observations in each set-up
• Minus Phosphorus–Very minimal shoot growth–Very minimal root growth–Violet coloration of leaf sheaths–Root system is very fragile– Interveinal Chlorosis–Necrosis
Observations in each set-up
• Minus Potassium–Marginal Necrosis–Very poor root growth–Very poor shoot growth–Leaves were twisted, curled and fragile– Necrosis
Observations in each set-up
• Distilled Water–Chlorosis–Light green color–Very good root growth, but poor in
lateral roots–Violet leaf sheaths–Fragile shoot system
DISCUSSION
Hydroponics – the set-up
• Soil-less culture• Inorganic solution that contain nutrients• Roots of plants are immersed on the
solution• Continually aerated and exposed to
sunlight
Sample set upWith aerator, nutrients in the aqueous solution
Hydroponics – the set-up
• Better than the soil–chronic and acute deficiencies of several
elements may occur simultaneously–absence or excessive amounts of one
element may induce deficiencies or excess accumulations of another
–some virus-induced plant diseases may produce symptoms similar to those of nutrient deficiencies
Different hydroponic
set-ups
Hydroponics – the solution
• Sachs’ solution - contributed a total of nine mineral nutrients (K, N, P, Ca, S, Na, Cl,Fe, Mg)
• Hoagland solution–contain all of the known mineral elements
needed for rapid plant growth–Used in our experiment (slightly
modified)
Stock Solution
1Complete
2-N
3-P
4-K
5Distilled
H2O
1 M Ca(NO3)2 5 mL - 5 mL - -
1 M KNO3 5 mL - 5 mL - -
1 M MgSO4 2 mL 2 mL 2 mL 2 mL -
1 M KH2PO4 1 mL 1 mL - - -
FeEDTA 2 mL 2 mL 2 mL 2 mL -
Micronutrients 1 mL 1 mL 1 mL 1 mL -
1 M NaNO3 - - - 5 mL -
1 M NaH2PO4 - - - 1 mL -
1 M CaCl2 - 5 mL - - -
1 M KCl - 5 mL 1 mL - -
Hydroponics – the solution
• Modified Hoagland Solution–Concentrations of the elements were
set to their optimum levels in such a way that it will not produce any toxicity symptoms or salinity stress
–E.g. source of nitrogen which is ammonium (NH4
+) and nitrate (NO3-)
Hydroponics – the preparations
• Distilled water must be first placed in each bottle to prevent formation of precipitations
• one-week old germinating Zea mays –easily germinated –widely available–stored endosperm – food of the germinating
seed–suitable height for the transport of the
nutrients
Hydroponics – the preparations
• Proper aeration–provide the roots of the plants with sufficient
oxygen for their aerobic respiration• Maintenance of solution
– to replenish the consumed nutrients –and to remove by-products of metabolism
• Maintenance of pH –within 5.5 to 6.5 –element abundance is dependent to it
Essential Elements
• Nutrient deficiency symptoms - the expression of metabolic disorders resulting from the insufficient supply of an essential element.
• Two types of elements based on their mobility1. Mobile
2. immobile
Mobile – deficiency seen in old leafImmobile – deficiency seen in young leaf
Essential Elements – Categories
1. Based on Abundancea. Micronutrients – Cl, Fe, I, B, Mn, Na, Zn,
Cu, Ni, Mo
b. Macronutrients – N, K, Ca, Mg, P, S, Si
Essential Elements – Categories
2. Based on biochemical roles and physiological function
a. G1: forms the organic components of the plant
b. G2: important in energy storage or maintaining structural integrity
c. G3: of the free ions or ions bound to pectic acids present in the plant cell wall
d. G4: important roles in electron transfer
Nitrogen (NH4+, NO3
-)
• Functions– constituent
of many important cell components • Amino acids• Nucleic acids• Chlorophyll• hormones
• Deficiencies – inhibited plant
growth–Chlorosis–woody stems – formation of purple
pigmentation
Observations in each set-up
• Minus Nitrogen–Very poor shoot growth–Interveinal Chlorosis–Violet leaf sheaths
Phosphorus (HPO4−, HPO2−)
• Functions–DNA and RNA–Sugar-phosphate
int. :RuBP –plant
metabolism: ATP–phospholipids
• Deficiencies–Stunted growth–Necrosis–Purple
coloration–Slender stems–Delayed
maturation
Observations in each set-up
• Minus Phosphorus–Very minimal shoot growth–Very minimal root growth–Violet coloration of leaf sheaths–Root system is very fragile– Interveinal Chlorosis–Necrosis
Potassium (K+)
• Functions–regulation of
osmotic potential in plant cells
–Activation of enzymes in respiration and photosynthesis
• Deficiencies–chlorosis necrosis–Leaf curl and crinkle–slender and weak–abnormal short
intermodal region– roots susceptible to
rotting due to fungi– tendency to lodge off
Observations in each set-up
• Minus Potassium–Marginal Necrosis–Very poor root growth–Very poor shoot growth–Leaves were twisted, curled and fragile– Necrosis
Observations in each set-up
• Complete–Short roots but high amounts of lateral
roots–Good shoot growth–Lively green leaves–Minor chlorosis at leaf tips–Generally healthy
Observations in each set-up
• Distilled Water–Chlorosis–Light green color–Very good root growth, but poor in
lateral roots–Violet leaf sheaths–Fragile shoot system
CONCLUSION
1. To become familiar with the method of growing plants by hydroponics
Hydroponics – uses a soil-less culture that uses only inorganic solutions as source of nutrients where the roots of the plant are immersed and are continually aerated, and exposed to ample sunlight
2. To observe deficiency symptoms associated with inadequate supplies
of selected essential element
• Minus Nitrogen - inhibition of growth and yellowing of leaves
• Minus Phosphorus - dark green coloration of leaves or necrosis and stunted growth
• Minus Potassium - plant lodged off and exhibited curling and necrosis in leaf tips
The Conclusion
• Essential elements – needed by plants to grow and develop (N, P, K)
• Specific functions can be observed using methods such as hydroponics
• Deficiency symptoms are reflective of the nutrients’ functions
• Nitrogen influences plant growth, phosphorus stores energy, and potassium regulates osmotic potential
GUIDE QUESTIONS
Study Questions
• What can be deduced from the relative age of organ showing the first sign of deficiency for a given nutrient?
Helps determine mobility of nutrients
Study questions
• Why are dark colored containers preferably used in culture solution studies?
In order to keep out lightreduce the growth of algae that would
compete with the plants for nutrientsPrevent reactions of chemical that can
be induced by light
Study questions
• Why is it necessary to observe aseptic protocols in the experiment?
to avoid contaminationeven a little increase or decrease in the
nutrient content can have a considerable effect on the results, making them unreliable
Study questions
• Give examples of plants that have been grown using hydroponics (not necessarily in the Philippines).
WatercressTomatoesPepperLettuceSeedless cucumber
Study questions
• Soil-less agriculture is practiced extensively in Israel. Why do you think so?
country lacking in fertile agricultural landdeserts (not efficient in water retention)less organic materials – less retention
for nutrients (low CEC)
REFERENCES
• F. Evangelista. 2012. Lecture in Plant Nutrition in a plant physiology course. Gat Andres Bonifacio bldg., University of the Philippines, Manila
• Hopkins. 2009. Introduction to Plant Physiology 4th Edition. John Wiley & Sons, Inc. United States of America
• Taiz & Zeiger. 2002. Plant Physiology 3rd Edition. Sinauer Asssociates Inc., Publishers, Sutherland, Massachusetts
• Plant Mineral Nutrition PowerPoint. 2010
Prepared byUy, Masa, Josue, De layola,
CortezPlant Physiology Laboratory, WAB2
August 8, 2012