ผลของระยะปลูกต่อการเจริญเติบโต ผลผลิต และปริมาณสารแคนนาบิไดออล ของกัญชงที่ปลูกในแปลงกลางแจ้ง

Watcharin Jantawan; Orapin  Saritnum; Ravee  Ganeshaborirak; Seksan  Songchainthuek; Winai  Wiriya-Alongkorn

doi:10.14456/jare-mju.2026.1

Authors

Watcharin Jantawan Faculty of Agricultural Production, Maejo University, Chiang Mai, Thailand https://orcid.org/0009-0001-2632-6709
Orapin Saritnum Faculty of Agricultural Production, Maejo University, Chiang Mai, Thailand
Ravee Ganeshaborirak Faculty of Agricultural Production, Maejo University, Chiang Mai, Thailand
Seksan Songchainthuek The Office of Agricultural Research and Extension, Maejo University, Chiang Mai, Thailand
Winai Wiriya-Alongkorn Faculty of Agricultural Production, Maejo University, Chiang Mai, Thailand

DOI:

https://doi.org/10.14456/jare-mju.2026.1

Keywords:

plant spacing, hemp, cannabidiol, factor, variety

Abstract

Since the legalization of the cultivation, utilization, and research of hemp and cannabis plants in Thailand in 2022, commercial cultivation of these crops has significantly increased. However, such enterprises have experienced varying outcomes, including both successful ventures and substantial financial losses, mainly due to insufficient knowledge, especially regarding optimal plant spacing and appropriate varieties for open-field cultivation. This study was conducted at the Hemp Research and Development Center, Maejo University Chiang Mai, Thailand. The experiment followed a 3×3 factorial arrangement in a randomized complete block design (RCBD), with factor 1 being plant spacing (1×1 m, 2×1 m, and 2×2 m), and factor 2 being hemp variety (EHFGP#1, EHFGP#3, and EHFGP#8). The results showed that plant spacing had a significant effect on plant height, plant canopy diameter, number of nodes per plant, number of branches per plant, inflorescence size, fresh flower yield per plant, dry flower yield per plant, and dry flower yield per rai (1,600 m²). Interaction effects indicated that the EHFGP#3 variety, when planted at 1×1 m spacing, had the highest average plant height at 238.38 cm. EHFGP#1, when planted at 2×1 m and 2×2 m spacing, produced the highest number of nodes and branches per plant, with statistically significant differences. Inflorescence size varied with both variety and plant spacing. A 2×2 m spacing resulted in the largest inflorescence size for EHFGP#3 and EHFGP#8, while a 2×1 m spacing produced the largest inflorescence size for EHFGP#1. In terms of cannabidiol (CBD) content, cultivar was a highly significant factor. Cultivars EHFGP#1 and EHFGP#3 exhibited the highest CBD concentrations, ranging from 11.76–12.93% and 11.79–13.10%, respectively. The interaction between cultivar and plant spacing was significant; however, plant spacing alone had no effect on CBD content.

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