University of Isfahan Taxonomy and Biosystematics 3115-9001 15 56 2023 11 22 Assessment of morphological traits variation of Mentha piperita L. genotypes of different origins of Iran ارزیابی تنوع صفات ریخت‌شناسی ژنوتیپ‌های نعناع‌فلفلی ایران با منشأهای مختلف 79 94 28538 10.22108/tbj.2024.141658.1268 EN Zahra Bashir Zadeh MSc, Department of Horticultural Science, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Mehdi Mohebbadini Professor, Department of Horticultural Science, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Roghayeh Fathi Assistant Professor, Department of Horticultural Science, Faculty of Agriculture and Natural Resources, University of Lorestan, Khorramabad, Lorestan, Iran. Seyed Yaghob Seyed Masoumi Assistant Professor, Department of Crop and Horticulture, Research and Education Center for Agriculture and Natural Resources of Ardabil Province, Agricultural Research, Education and Extension Organization, Ardabil, Iran. Journal Article 2024 05 29 Peppermint (<em>Mentha piperita</em> L.) from the Lamiaceae family is one of the most widely used medicinal plants. Due to the importance of morphological trait variation in the management of plant germplasm for plant breeding, as well as the preservation of valuable genetic reserves in breeding programs, further morphological studies are needed. In this research, different accessions of this plant were collected from various regions of Iran (Ardabil, Hamedan, Kordestan, Golestan, Meshginshahr, Firoozabad, Noorabad, Zanjan, Tabriz, Orumieh, and Shiraz). An experiment was conducted in 2021 based on a randomized complete block design to evaluate the morphology of these accessions in the Meshginshahr climatic condition. Analysis of variance showed significant differences between the populations in traits. Comparison of mean traits in total showed that important traits such as leaf width (1.22-1.67 cm), petal length (0.20-0.35 cm), stem diameter (0.20-0.27 cm), leaf length (2.48-3.34 cm), leaf petiole (0.53-2.16 cm), leaflet width (0.31-0.50 cm), and number of leaves (22.83-92) varied among accessions. The maximum correlation was observed between leaf petiole and pedicel length (0.98), while the minimum correlation was observed between the number of inflorescences and petal length (0.01). Cluster analysis classified the accessions into two major groups. The results suggested that <em>Mentha piperita</em> L. accessions from Iran have high genetic diversity, which can be utilized in breeding programs. https://tbj.ui.ac.ir/article_28538_ab502d5c96715936d21d1961297ea266.pdf