Effect of plant growth regulators on growth and seed yield of onion

Abstract

Onion is an important vegetable crop grown in almost all parts of the world as a flavouring agent in food preparation. It is propagated by bulb or seeds. The field experiment was carried out during 2023-24 at Department of Vegetable Science, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. Presence study aimed to find out the effect of different plant growth regulators on growth and seeds yield of onion at different concentration-Ethephon (100 & 200 ppm), Cycocel (100 & 200 ppm), Paclobutrazol (100 & 200 ppm) and Brassinosteroid (0.5 &1 ppm) on onion (Allium cepa L.). Two foliar sprays of these plant growth regulators are given at seed scape emergence stage and flower initiation after planting of bulbs. The statistical design adopted for experiment was randomized block design (RBD) with three replications and nine treatments. The observation recorded for vegetative growth in terms of Plant height, number of leaves per plant, number of seed stalks per plant, number of primary umbels per plant, number of secondary umbels per plant, yield parameters viz. flowers per primary and secondary umbels, seed weight of primary and secondary umbels, yield per plant, yield per plot, and yield per hectare, post harvest parameters viz. 1000 seed weight of primary and secondary umbel, germination percentage of seed of primary and secondary umbel were observed. The results showed that 200 ppm CCC significantly reduced the plant height and increased number of leaves, and number of seed stalks, number of primary and secondary umbels were found with Ethephon 200 ppm. The Ethephon application also significantly improved flowers per umbels, seed weight per primary and secondary umbel, yield per plant, yield per plot, yield per heactare, 100 seed weight of primary umbel, germination% of primary and secdondary umbel were recorded with ethephon 200 ppm. Hence, foliar spray with ethephon 200 ppm followed by CCC 200 ppm were found to be effective in improving the seed yield and seed quality in onion.