The manipulation of the ploidy level of plant species has been suggested as a relevant strategy to obtain greater biomass (Lavania, 2005; Caruso et al., 2013; Xu et al., 2014). Polyploidy induced in medicinal plants is generally a successful strategy for obtaining highly productive species, as seen in Salvia miltiorrhiza (Bunge) polyploids (Gao et al., 1996), Artemisia annua (L.) (De Jesus-Gonzalez and Weathers, 2003), Panax ginseng (C. A. Mey.) (Kim et al., 2004), Centella asiatica (L.) Urb. (Kaensaksiri et al., 2011), Pinellia ternate (Thunb.) Makino (He et al., 2012), and Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson (Julião et al., 2020).

Pfaffia glomerata (Spreng.) Pedersen is commonly known as Brazilian ginseng and its tuberous roots are of commercial interest due to the presence of a wide variety of triterpene saponins, including its major active compound the phytoecdysteroid 20-hydroxyecdysone (20E)(Nicoloso et al., 1999; Vigo, 2004). The 20E present in the hydroalcoholic extract of P. glomerata (diploid) induced changes in the testicular microstructure caused by the increase in reactive oxygen species, leading to the death of testicular germ cells (Dias et al., 2019). In females, the extract induces embryonic and fetal loss, as well as the occurrence of malformations (Barilli and Montanari, 2008). Nevertheless, Brazilian ginseng has been widely used in traditional medicine as an aphrodisiac (Dias et al., 2020a; Matta et al., 2020). In this context, the polyploidization of P. glomerata resulted in plants with greater photoautotrophic potential in vitro, also showing higher biomass accumulation and production of 20E ex vitro (Corrêa et al., 2016; Gomes et al., 2014).

Previous studies show that hydroalcoholic extract of P. glomerata diploid caused changes in the testicular microstructure caused by oxidative stress, leading to the death of testicular germ cells (Dias et al., 2019). Such changes decreased sperm production and quality, leading to an increase in post-implantation loss in females who did not receive treatment with the extract (Dias et al., 2020b). In addition, it also caused an increase in the corpora cavernosa and penile NO (Dias et al., 2020a). Therefore, the present study aimed to evaluate the effects of the hydroalcoholic extract of P. glomerata tetraploid root in the seminiferous tubules, sperm quality, and fertility of adult Swiss mice.