The growth regulator used to reduce flower drop in chilli is

The growth regulator used to reduce flower drops in chili is NAA.
Spraying of NAA (20 ppm) at 30 days after planting to get early flowering, increased number of flowers, fruit set, and reduced flower drop and fruit drop.
Spraying of NAA (50 ppm) at the beginning of flowering in chili was found to reduce flower drop as compared to control.