Effect of different growth regulators on vegetative growth and fresh fruit yield of squash

sDuring the two consecutive summer seasons of 2021 and 2022, a field experiment was conducted at the Research Farms of the vegetables department, Horticultural Research Institute (HRI), Agriculture Research Center, Kaha, Qalubia Governorate, to investigate the effects of applying ethephon (ETH), salicylic acid (SA), and naphthalene acetic acid (NAA), using three distinct concentrations (50, 100, and 200 mg per liter) and different application methods (soaking the seeds, foliar spraying plants, and soaking +foliar spray) regarding the vegetative growth and fresh fruit output of summer squash plants (Cucurbita pepo) cv. Eskandrani. Results revealed that the treatment with salicylic acid (seed soaking + plant spraying) or NAA (seed soaking) at 100 mg/l was more efficient in increasing the number of summer squash leaves and plant height, Furthermore, the best treatment concerning increasing early yield, quantity of fruits and overall fruit production per plant was seed soaking using ethephon at the different concentrations in both seasons.