Influence of plant growth regulators on yield attributes and physical parameters of fruit quality in sapota under the eastern tropical region of India

The present study was conducted at Central Horticultural Experiment Station (ICAR-IIHR), Bhubaneswar, during 2022 and 2023 to evaluate the impact of the application of plant growth regulators on fruit set, yield and physical fruit quality of Sapota (Manilkara zapota L.) cv. DHS-1. The experiment was designed in a randomized completely block design with nine treatments consisting of NAA (50 and 100 ppm), CPPU (5 and 7.5 ppm), SA (150 and 300 ppm) and Homobrassinolide (10 and 15 ppm) and water as control. Treatments were imposed on 24-year-old, uniformly grown sapota trees, planted at 10m x 10m spacing, at flowering, fruit set and one month after fruit set. In general, the application of PGRs was effective in augmenting fruit sets, fruit retention, yield attributes and physical fruit quality over control. However, the application of NAA and CPPU performed better at higher doses. The treatment NAA @100 ppm resulted in the highest fruit set (34.76 %), fruit retention (57.46% at 30 DAFS, 28.48 % at 120 DAFS), yield (47.77 kg/tree) and physical fruit viz. pulp content (93.80%), dry matter (26.15%), fruit length (7.47 cm) and fruit width (6.57 cm). Pearson correlation coefficient analysis showed positive links among fruiting, yield, yield attributing traits and physical fruit quality parameters of sapota, as well as a negative correlation for peel content.