EFFECT OF BOTTOM HEAT TEMPERATURES ON ROOTING OF MANGO CUTTINGS OF DIFFERENT CULTIVARS.
For all cultivars the highest rooting rate was found with time at 25°C and 30°C without significant difference between the two temperatures. At a temperature of 20°C rooting occured more slowly and with time good rates were obtained with 'Turpentine', 'Gomera', 'Sabre' and poor rates with '13–1' cuttings. At 35°C rooting was significantly suppressed in 'Gomera', 'Sabre' and '13–1' and only 'Turpentine' cuttings rooted at a high rate.
Significant differences were found in rooting capability of the cultivars in the following order: 'Turpentine', 'Gomera', 'Sabre', '13–1'. The number of roots per cutting was higher at the beginning than at the end of the experiment, it also differed between cultivars and was not affected by the bottom heat temperature.
Since no significant differences were found in the root system of established plants grown at different bottom heat temperatures, it is suggested that bottom heating of the medium during rooting has a qualitatively inductive effect on initiation of roots.