Vol. 10, Issue 9 (2021)

Author(s):
Pravin, Dr. VNP Sivarama Krishna, Dr. G Thanuja Sivaram, Dr. M Jayaprada and Dr. Y Sireesha

Abstract:
The present investigation was conducted at Fruit Science block, Department of Fruit Science, College of Horticulture, Anantharajupeta, Dr. Y.S.R. Horticultural University, Andhra Pradesh during the year 2020-21. The experiment was laid out in completely randomized design for germination parameters and factorial concept for physiological parameters with two factors and three replications. Result of present investigation revealed that the custard apple seeds soaked in S₂ (Thiourea @ 500ppm for 12hr) found significantly maximum number of leaves at 30 DAS, whereas S₁ (GA₃ @ 200 ppm for 12hr) was found better for germination viz. days taken for germination, percentage of germination, plant height and physiological parameters viz. rate of photosynthesis, rate of transpiration, stomatal conductance, leaf temperature, internal cellular CO₂. Among the foliar spray of different growth substances, custard apple seedlings sprayed with F₁ (GA₃ @ 200ppm) was found better for rate of photosynthesis, rate of transpiration, stomatal conductance and F₃ (19:19:19 @ 1%) was found better for leaf temperature, internal cellular CO₂ at 45 and 60 DAS. Considering the interaction effect between seed treatment and foliar spray of chemical substances, found better for rate of photosynthesis, rate of transpiration, stomatal conductance in custard apple seedlings receiving treatment combination of S₁F₁ (GA₃ @ 200 ppm for 12hr as a seed treatment and GA₃ @ 200 ppm at 45 and 60 days after sowing as a foliar spray) and S₁F₃ (GA₃ @ 200 ppm and 19:19:19 @ 1%) was found better for leaf temperature, internal cellular CO₂.