Biotic activation of abiotic temperature stress tolerance in transgenic BT and wild type cotton

Activation of abiotic temperature stress tolerance in transgenic Bt and non-Bt cottonwas studied using Pseudomonas fluorescens as biotic regulator. Seeds germinated at differenttemperatures after the bacterial treatment exhibited variation at the temperatures of 30°C and37°C as measured in terms of percent seed germination in both Bt and non-Bt cotton.Pseudomonas treatment enhanced the seed germination in non-Bt cotton at 30°C.Enhancement of seed germination in Bt cotton was significant at 37°C after bacterialtreatment. At elevated temperature of 45°C, neither Bt nor non-Bt seeds germinated,irrespective of Pseudomonas treatment. The temperature of 30°C supported better shoot androot growth of seedlings as compared to other temperatures tested. Pseudomonas treatmentresulted in enhanced shoot and root length of Bt cotton seedlings at 30°C, whereas at 37°Chad negligible influence. Non-Bt cotton seeds treated with bacteria failed to show significantvariation in root and shoot growth compared to untreated control. Activity gelelectrophoresis carried out to study the expression of superoxide dismutase revealed that theSOD activity in both Bt and non-Bt cotton was enhanced due to Pseudomonas seed treatment.