Effect of Plant Growth Regulators on Seed Treatment and Foliar Spray of Okra (Abelmoschus esculentus L.)

Abstract

Aim: The present investigation was conducted at the Agricultural Research Farm, Suresh Gyan Vihar University, Jaipur, to evaluate the influence of plant growth regulators as seed treatments and foliar sprays on okra (Abelmoschus esculentus L.). Place and Duration of Study: The field experiment was conducted during the kharif season of 2025–2026. Methodology: The experiment comprised eight treatments: Control (T₁), GA₃ @ 50 ppm (T₂), Ethrel @ 200 ppm (T₃), 2,4-D @ 5 ppm (T₄), Triacontanol @ 0.5 ml of 0.1% (T₅), NAA @ 10 ppm seed soaking + 5 ppm foliar spray (T₆), BAP @ 50 ppm (T₇) and CPA @ 50 ppm (T₈). Treatments were arranged in a Randomized Block Design (RBD) with three replications. Observations were recorded on reproductive parameters including days to first flowering, days to 50% flowering, days to first harvest, fruit diameter, number of fruits per plant, fruit length, and fruit weight. Results: Application of plant growth regulators significantly influenced all reproductive parameters of okra. Triacontanol (T₅) induced the earliest flowering (34.68 days) and first harvest (49.99 days), while 2,4-D (T₄) recorded the minimum days to 50% flowering (44.03 days). Triacontanol also produced the maximum fruit diameter (1.88 cm), fruit length (13.19 cm) and fruit weight (17.23 g). The highest number of fruits per plant (36.38) was observed with NAA (T₆), followed closely by Triacontanol (35.13). In contrast, the untreated control recorded delayed flowering, later harvest, and the lowest values for all reproductive traits. The superior performance of Triacontanol may be attributed to enhanced photosynthetic efficiency, improved assimilate translocation and better hormonal regulation, resulting in early floral initiation and improved fruit development. Conclusion: Among the plant growth regulators evaluated, Triacontanol @ 0.5 ml of 0.1% applied through seed soaking and foliar spray proved to be the most effective in enhancing the reproductive performance of okra by promoting early flowering, early harvesting, and superior fruit quality attributes. Therefore, Triacontanol can be recommended for improving the reproductive phase and productivity of okra under the agro-climatic conditions of Jaipur, Rajasthan.