Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
In situ apoplastic pH calibration curve for Oregon Green 488 dextran fluorescence excitation ratio R (490 excitation/440 excitation; 525 emission) in maize leaves. The Boltzmann fit was chosen for fitting sigmoidal curves to in situ calibration ratio data. Fitting resulted in an optimal dynamic range for pH measurements between 3.2 and 6.6 (corresponds to the ratios 0.95 and 2.15). In situ calibration was conducted on 12 different plants.
