Impact of Auxin and Gibberellin on Vegetable Crops: A Review

Plant growth regulators, also known as phytohormones, are a class of organic chemicals, either naturally occurring or artificially synthesised, that exert control over specific physiological processes in plants. The application of these substances elicits a range of effects on vegetables, encompassing seed germination, the disruption of seed dormancy, the commencement of flowering, the induction of gametocidal effects, the promotion of fruit set, the stimulation of parthenocarpy, and the facilitation of fruit ripening, among others. Auxin plays crucial factor in the development of several vegetable crops, including cucurbits. Notably, the application of Naphthalene acetic acid at a concentration of 10 ppm has been observed to exert a significant influence on sex expression, fruit set, and overall production in cucumber plants. The application of 4-CPA resulted in the greatest quantity of commercially viable fruit in tomato plants. The application of Naphthalene acetic acid at a concentration of 40 ppm exhibited the most substantial enhancements in leaf area, percentage of fruit set, total fruit production, as well as the quantity and weight of seeds per fruit in chilli plants. The treatment involving the application of 80 ppm Naphthalene acetic acid in brinjal resulted in the observation of increased fruit length, average weight of fruit per plant, and greatest fruit diameter. Gibberellin is also of significant importance, since it participates in using the gibberellic acid route to produce tomato plants that exhibit enhanced performance in both irrigated and water-limited environments, hence increasing their drought tolerance. The application of GA3 at a concentration of 75 ppm has been found to be highly beneficial in improving vegetative growth and yield characteristics in brinjal, as well as in several other vegetable crops as detailed in the present study. Additionally, they serve a crucial function in augmenting the output and productivity of many vegetables breeding programmes, and ensuring food safety.