Determining the Water Potential of Potato Tubers Using Gravimetric anc Chardakov Techniques

1522 Words4 Pages
bulb-icon

Recommended: how to determine the water potential of potato tuber cells practical

Determining the Water Potential of Potato Tubers using Gravimetric and Chardakov Techniques

1. INTRODUCTION:

Water potential (W) is the measure of free-energy status of water in plant cell, which is the driving force governing the movement of water into and out of the plat cell and affect various metabolic activities (O’Leary, 1970). Water potential is depends on different solute concentrations, pressure and matrix a particle; measured in Mega Pascal’s (MPa) and written as:

W = s + p + m

In plants dissolved solutes such as ions, sugars, proteins, amino acids and other substances decrease the availability of free energy and induce solute potential (S) , having a negative value. Another factor affecting W is the pressure potential (P) which could be either positive for turgor cells or zero for flaccid cells or negative for cells with active transpiration. Also the binding of water to colloids which decreases water potential is known as Matric Potential (m), it is often small and considered a component of solute potential (Saupe), so for convinces it is ignored and now the equation is:

W = s + p (1)

Water Potential can be determined by measuring the equilibrium vapor pressure, which can be measured by varied methods based on different parameters for this purpose utilizing gravimetric parameters (Length, volume and weight) or Chardakov methods of using specific gravity changes (O’Leary, 1970) or Chardakov pressure bomb chamber or Freezing Point Depression determination using hydrolytic pressure chambers or Cryoscopic or Oblioscopic methods amongst others ( Bland and Tanner, 1985). In this experiment The Gravimetric and Chardakov techniques are used for determining the W for potato tubers by incubation in inc...

... middle of paper ...

...of the water potential of stored potato-tubers. Plant Physiology 79 (3), p 891-895. Available From: http://www.plantphysiol.org/content/79/3/891

O’Leary J. W. (1970). A Critical Evaluation of Tissue-Immersion Method for Measurement of Plant Water Potential. Ohio J. of Sci., 70(1), p 34-38. Available from: http://kb.osu.edu/dspace/handle/1811/5510 33 [Access date: April 12, 2014]

Ros Barcelo A., Calderon A. and Munoz R. (1994). Measuring water conductivity coefficients in plant tissues. Journal of Biological Education, 28 (2), p 83 – 85. from: http://www.tandfonline.com/doi/abs/10.1080/00219266.1994.9655371 [Access date: April 12, 2014]

Saupe S.G. Measuring the Water status of Potato tubers. St. John’s University, Minnesota. [Online] Available from: http://employees.csbsju.edu/ssaupe/biol327/Lab/water/water-lab-intro.htm [Access date: April 12, 2014]

Show More
Related

  • The Effect of Gibberellic Acid on Wild Type and Rosette Brassica rapa Plants

    831 Words  | 2 Pages

    Two members of the group were instructed to visit the laboratory each day of the experiment to water and measure the plants (Handout 1). The measurements that were preformed were to be precise and accurate by the group by organizing a standardized way to measure the plants. The plants were measured from the level of the soil, which was flat throughout all the cups, to the tip of the apical meristems. The leaves were not considered. The watering of the plants took place nearly everyday, except for the times the lab was closed. Respective of cup label, the appropriate drop of solution was added to the plant, at the very tip of the apical meristems.

    Read More

  • The Effect of Recycled Water Irrigation on Young Olive Trees

    1166 Words  | 3 Pages

    The effect of water quality on Vegetative measurements and photosynthesis indices of the trees are presented in Table 1. No significant differences were found between parameters: gs, shoot number in both years, but others were higher in RW application. Height of trees and leaf area in first year was not significant but in second year it increased by 42 and 29% respectively in application RW. Photosynthesis rate appears significantly higher (23.4 µmol m−2 s−1) in plants receiving recycle water than clean water.

    Read More

  • Osmosis Diffusion Investigation Lab Report

    1986 Words  | 4 Pages

    Diffusion and osmosis are necessary for the efficient transport of substances in and out of living cells. Diffusion is the most common and effective transportation process between cells and their surroundings, the movement of a substance along a concentration gradient from high to low, allowing essential nutrients and compounds to be transported without expending energy. Osmosis is a special kind of diffusion, specific to water. In order to observe diffusion and osmosis in real and artificial cells, a series of experiments was put together to observe how the surface area to volume ratio effects the rates of diffusion by using agar in different shapes with different ratios, next the rate of diffusion due to tonicity was observed using different solutions with different tonicities. And lastly live plant cells were submerged in different solutions with varying water potentials to observe how was potential effects the rate of osmosis and diffusion. It was concluded that the larger surface area to volume ratio, the faster rate of diffusion, the hypertonic solutions caused water to leave a cell and the hypotonic solutions allowed water to enter a cell, and that water potential will move from high to low in an attempt to maintain equilibrium.

    Read More

  • Potato Osmosis Lab Report

    923 Words  | 2 Pages

    The purpose of the Tonicity lab was to help identify the effects of an isotonic, hypertonic, and hypotonic solution to a slice of potato. The difference between diffusion and osmosis is that diffusion is the movement of particles or molecules from a region of higher concentration to a region of a lower concentration. While osmosis consists of the movement of water molecules through a semipermeable from a region of high water concentration to the region of less water concentration (Major Differences). Tonicity is the ability of a solution to ?alter the internal water volume of a cell? (Difference Between Solution, 2013). An isotonic solution should keep their normal shape; the osmotic pressure outside the cell has the same pressure within the cell. A hypotonic solution, are more dilute and contain a lower concentration of nonpenetrating solutes than cells. In contrast, a hypertonic solution have a higher concentration of

    Read More

  • The Hoover Dam

    1748 Words  | 4 Pages

    Snyder, R. (2009). Water In The Greenhouse. Growing Produce. Retrieved on March 20, 2014 from http://www.growingproduce.com/uncategorized/water-in-the-greenhouse/

    Read More

  • Effect of Intraspecific Competition on the Biomass and Height of Helianthus Annuus

    1250 Words  | 3 Pages

    Our subject plant for this experiment is Helianthus annuus, a common sunflower plant cultivated all over the world for its seeds and seed oil. Helianthus is an annual plant that grows from 1 to 3 meters, depending on conditions. It is for this reason I chose Helianthus as our subject plant. Shorter plants have a less measurable variable. Helianthus plants, with their long straight stems, would have a much easier variable to measure. A total of 24 Helianthus plants, six to each pot, will be used in the treatment. The large number of subject plants is because of genetic variation that might sway my results if I were to use only a single treatment pot.

    Read More

  • Osmosis Through A Semi Permeable Membrane Using Dialysis Bags

    2246 Words  | 5 Pages

    In this experiment we took dialysis bags and filled them with various sucrose solutions and put them in water over a period of about 90 minutes to look at the osmosis in each bag and the tonicity of each environment the bags were in. We also took potato pieces and submerged them into various sucrose solutions to determine the ideal state of tonicity for plants and the osmosis that occurred over a period of time. The final results for the first exercise was that 0.8M sucrose solution gained the most mass and that it was hypertonic to its environment. The overall results for exercise 2 was that 1.0M sucrose solution lost the most amount of mass and was hypotonic to its environment.

    Read More

  • Essay On Potato Lab

    774 Words  | 2 Pages

    We will be testing how the size and shape of a potato changed based on what water solution it is placed in. There will be 5 different solutions. 1. Pure water (No Sugar added) 2. 10% sugar 3. 20% sugar 4. 30% sugar 5. 40% sugar.

    Read More

  • Yuma: Beginning Anew

    904 Words  | 2 Pages

    For some people irrigation systems may not sound interesting or useful, however; they play a huge role in keeping produce alive and well-watered. Be...

    Read More

  • Potato Osmosis Lab

    836 Words  | 2 Pages

    In order to understand the concept of the three solutions; hypertonic, hypotonic, and isotonic, used in the experiment one must learn to understand the concept of how and why molecules move by processes of osmosis. As conducted, this hands-on experiment will help you examine water molecule movement when exposing the plant cell that make up the potato to be either hypertonic or hypotonic solutions. Although, plant cells have rigid cell walls external to the plasma membrane versus animals that do not make a difference that can result in an opposite outcome when being placed in these two solutions. I believe that experiment b (potato mixed with salt and water) will be more affected since it will conflict

    Read More

  • Lab Report: Concentration of Sucrose Affect on Osmosis

    1609 Words  | 4 Pages

    The variables I could change would be the temperature of the solution. The higher the temperature of the solution the more osmosis would occur. The surface area of the potato strip, the larger the surface area the more osmosis would occur as there would be more area exposed for osmosis to take place. The concentration of the solution will affect osmosis, the higher the concentration the less osmosis would take place. The duration of the experiment also affects how much water is gained/lost by osmosis as the longer the duration is, the more osmosis would take place (osmosis would stop as soon as it reaches an equilibrium of water content inside and outside the cell.

    Read More

  • Osmosis Lab Report

    1858 Words  | 4 Pages

    This occurs as in the process of osmosis, the water moves from a dilute solution to a more concentrated solution through a protein pore or semi-permeable membrane, without the expenditure

    Read More

  • A Comparison of the Water Potential of Potato and Sweet Potato Tubers

    1827 Words  | 4 Pages

    the gain or loss of water when samples of the tissue are placed in a

    Read More

  • Potato Osmosis Lab

    281 Words  | 1 Pages

    In this experiment, the effect of osmosis on the weight change of a potato was examined. The purpose of this lab was to study whether the weight or volume of the potato was effected if there was an increase or loss of water.

    Read More

  • Effect Of Sucrose Hypothesis On The Concentration Of Osmosis

    1066 Words  | 3 Pages

    If a plant cell is places in a hypotonic solution the cell has a lower water concentration to that of the solution. Water will move into the cell by osmosis from a high water concentration outside the cell to a lower water concentration inside the cell through a selectively permeable membrane. The cell becomes turbid

    Read More

More about Determining the Water Potential of Potato Tubers Using Gravimetric anc Chardakov Techniques

Open Document