COMPARATIVE EFFECTS OF 3-INDOLYLBUTYRIC ACID, 2,3,5-TRI-IODOBENZOIC ACID, AND β-NAPHTHOXYACETIC ACID ON FLOWER GROWTH AND FLOWER WEIGHT OF THE CAULIFLOWER (BRASSICA OLERACEA)
Three synthetic growth-promoting substances were administered to cauliflower plants (Brassica oleracea) to determine their effect on flower weight and flower growth. A Youden square experimental design was employed to set up treatment groups for all possible combinations of three substances at four concentration levels and three frequencies of application, and an untreated control group. The substances employed were 3-indolylbutyric acid (IBA), 2,3,5-tri-iodobenzoic acid (TIBA), and β-naphthoxyacetic acid (NOXA); concentrations used were 0.01, 0.2, 4.0, and 80.0 parts per million; and frequencies adopted were 2, 3, and 6 times in a 12-day period. Final flower weights were analyzed by an analysis of variance which showed that the treatments differed significantly (P <.01). Treatments with NOXA and IBA produced flowers weighing significantly more than those of the control group. Flower growth was characterized by a rapid initial rise, which subsequently levelled off in the control group. For treated groups, the initial rise continued throughout the flowering period. The results suggest that the use of certain synthetic growth-promoting substances may be feasible commercially for enhanced production of cauliflower crops.