2.6. Culture conditions, experimental design and data analysis
The in vitro experiments were performed with an incubation temperature of 25 ± 2 °C and a 16/8 h light/dark photoperiod provided by cool fluorescent lamps at 40 μmol m−2 s−1. All the experiments were set up in a completely randomized design and were conducted twice. Data were subjected to the analysis of variance using SAS ( SAS Institute Inc., 1999) software, and means were separated by Duncan's multiple range test at the 95% level ( Duncan, 1955).