The experiment was conducted during the cropping season of 2015-16 and 2016-17 at Department of Horticulture, College of Agriculture, Dapoli, Maharashtra on 35 years old uniform mango (cv. Alphonso) trees with an objective study the effect of plant growth regulators on suppression of post monsoon vegetative flush in mango. In the investigation the physiological behavior of the mango trees were assessed in relation to influence of plant growth regulator sprays. After 24 hours of treatment, the rate of photosynthesis was significantly varied due to foliar application of plant growth regulators. The rate was lowered down than control. Among the treatments, PBZ 2000 ppm treatment showed lowest rate of photosynthesis (6. 40 μmol CO2 m-2 Sec-1) and on par with CCC 1500 ppm and 3500 ppm treatments. The control had highest rate of photosynthesis (6. 65 μmol CO2 m-2 Sec-1). After two weeks of treatment, the rate of photosynthesis was significantly influenced due to treatments of different CCC and PBZ concentration. It was reduced compared to previous readings. The significantly lowest rate (5.30 μmol CO2 m-2 Sec-1) was recorded in CCC 3500 ppm and highest (7.62 μmol CO2 m-2 Sec-1) was in control. The respiration rate after 24 hours of treatment, did not differed significantly during first year but differed significantly in second year and it was significantly highest (2.37 μmol CO2 m-2 Sec-1) in PPP 2000 ppm treatment. The lowest rate (2.18 μmol CO2 m-2 Sec-1) was in PPP 500 ppm) and T7 (Control) treatments. The pooled data showed non significant effect of plant growth regulators on respiration rate at 24 hours after treatment. At two weeks after treatment, PBZ 2000 ppm treatment had highest respiration rate (2.53 μmol CO2 m-2 Sec-1) and the lowest rate (2.21 μmol CO2 m-2 Sec-1) was in control. The treatments of CCC were on par among themselves. No significant differences were observed in leaf transpiration rate after 24 hours of treatment. Whereas, it was significantly differed at two weeks after treatment only in the first year. The significantly highest transpiration rate (4.358 μmol H2O m-2 Sec-1) was recorded in PBZ 2000 ppm treatment and lowest rate (4.358 μmol H2O m-2 Sec-1) was in control. The stomatal conductance did not differ significantly as reading taken after 24 hours of treatment. At two weeks after treatment, the rate was significantly differed and highest stomatal conductance (0.220 μmol H2O m-2 Sec-1) was in control and lowest (0.156 μmol H2O m-2 Sec-1) in CCC 2500 ppm treatment.

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