Sharmila Tiwari¹ , Surendra Khadka¹ , Binaya Babu Koirala² , Padma Nath Atreya² , Arjun Subedi³ , Sudip Tiwari¹ , Nitika Pandey¹ , Amit Chhetri¹

1 Faculty of Agriculture, Agriculture and Forestry University, Rampur, Chitwan, 44209, Nepal
2 Temperate Horticulture Development Center, Marpha, Mustang, 33100, Nepal
3 Department of Horticulture, Agriculture and Forestry University, Rampur, Chitwan, 44209, Nepal
Author    Correspondence author
International Journal of Horticulture, 2026, Vol. 16, No. 3   doi: 10.5376/ijh.2026.16.0015
Received: 03 May, 2025    Accepted: 15 Jun., 2026    Published: 23 Jun., 2026

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Tiwari S., Khadka S., Koirala B.B., Atreya P.N., Subedi A., Tiwari S., Pandey N., and Chhetri A., 2026, Effect of different concentrations of gibberellic acid (GA₃) and naphthalene acetic acid (NAA) on growth and seed yield of cabbage at Marpha, Mustang, International Journal of Horticulture, 16(3): 164-171 (doi: 10.5376/ijh.2026.16.0015)

The experiment was carried out at Marpha, Mustang in order to determine the effect of different concentrations of plant growth regulators: Gibberellic acid (GA₃) and naphthalene acetic acid (NAA) on growth and seed yield of cabbage from February to July 2024. The experiment was laid out in one factor randomized complete block design (RCBD) with seven treatments. The treatments consist of application of different concentrations of GA₃ and NAA namely: T₁: Control (distilled water spray), T₂: GA₃-50 ppm, T₃: GA₃-75 ppm, T₄: GA₃-100 ppm, T₅: NAA-50 ppm, T₆: NAA-75 ppm and T₇: NAA-100 ppm. Each treatment was replicated 3 times. Thus, there were 21 plots consisting of 2 sample plants in each plot. So, there were total of 42 plants. Different growth parameters like peduncle height, number of leaves, number of branches, canopy cover and yield parameters like number of inflorescences, number of pods per inflorescence, number of seeds per pod, Thousand Grain Weight (TGW), seed yield per plant were assessed. The solution for spray was made using standard procedures. Application of the plant growth regulators was done twice; the first application was done at the time of head initiation and second application was done at 50% flowering. The data was first entered in MS excel and R-Stat was used for further analysis of the parameters. The application of GA₃ at 50 ppm (2.91 t/ha) was found most effective for seed yield than other treatments. The control treatment was found least effective in all parameters. Similarly, other growth and yield parameters like peduncle height, leaf number, number of pods per inflorescence and Thousand Grain Weight (TGW) were found to be highest by the application of GA₃ at 50 ppm. Hence the results revealed that the different concentrations of GA₃ and NAA significantly influenced seed yield of cabbage along with growth parameters.

Plant growth regulators; GA₃; NAA; Cabbage; Seed yield; Growth