اندازه گیری نفوذ پذیری نسبی غشاء به روش ژائو و همکاران (1992)

Membrane Permeability and Electrolyte Leakage

با تو جه به اینکه برای پی بردن به میزان خسارت اکسیداتیو وارد شده به فسفولیپیدهای غشای پلاسمایی بر اثر پراکسیداسیون ناشی از رادیکال های آزاد، اندازه گیری نشت الکترولیت ها یکی از بهترین روش ها می باشد لذا مطلب زیر می تواند راهگشای محققین برای درک بهتر تحمل یا حساسیت ژنوتیپ ها نسبت به تنش باشد. 

Leaves or leaf segments of heat-treated plants were cut into 1-cm2 pieces and placed in test tubes with 20 mL deionised distilled water (0.5-0.8 g fresh leaf tissue per sample). After vortexing the samples for 3 s, the initial electrical conductivity (EC₀) of each sample was measured. The samples were stored at 4°C for 24 h, and conductivity (EC₁) was measured again. Samples were then autoclaved for 15 min, cooled to room temperature, and conductivity (EC₂) was measured for a third time. The relative permeability of cell membranes was calculated using a slight modification of the method of Zhao et al. (1992) as:

 Relative Permeability (%) = ((EC₁-EC₀)/ (EC₂-EC₀))*lOO.

The tolerance of leaf cell membranes to high temperature also was estimated by continuously monitoring the electrical conductivity of the incubation solution while the temperature of the system was slowly increased. Approximately 3 g of leaf tissue was vacuum infiltrated with distilled deionised water for 10 min. Leaf pieces were then transferred to a glass beaker with 1 L of distilled deionised water and placed on a stirring hotplate. Controls were adjusted to provide gentle stirring and to increase the solution temperature from 25 to 70°C at a rate of 0.3-0.4"C m i d. Electrical conductivity and temperature were monitored using a conductivity meter (Fisher Scientific model 20) connected to a computer; data were logged at 20 s interval

Reference:

Zhao, Y., Aspinall, D., and Paleg, L.G. (1992). Protection of membrane integrity in Medicago saliva L. by glycinebetaine against the effects of freezing. Journal of Plant Physiology 140, 541-543.