A have data of A-Ci curves in quinoa. It was obtained using a leaf fluorometer chamber (LICOR). Using the lineal part of this curve is possible to get photorespiration data ?
an explicit model is given by Long and Brnacchi in http://www.planta.cn/forum/files_planta/gas_exchange_measurements_what_can_they_tell_us_about_the_underlying_limitations_to_photosynthesis_112.pdf
It is relevant to estimate Cc and to check model by using some comparative curve obtained in 1%O2 even if C3 photorespiration is quite conservative. Also Thom Sharkey and al produced biochemistry parameters from gas exchange routines for C3 in http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2007.01710.x/pdf and later john Evans made available SAS rouitnes for the Licor http://prometheuswiki.publish.csiro.au/tiki-index.php?page=Gas+exchange+measurements+of+photosynthetic+response+curves
I add that some spreadsheet has been removed by PCE publisher, LICOR and other cross references for reasons that I miss. A recent upgrade is available from Plant Cell Environment 2015 by Bellasio et al., but may require subscription to the juornal. for program details and modifications you may follow .Thom Sgarkey docs in Rg and ask the author at http://onlinelibrary.wiley.com/doi/10.1111/pce.12560/abstract
Dr. Bongi can you give me more details to use air with 1 % O2 or nitrogen with 1 % O2 ? What about the fluxes ? Do you know some references in relation to this ?