Genetic studies in Aloysia gratissima (Gill. et Hook) Tronc., Chenopodium mandonii (S. Watson) Aellen and Clinopodium gilliesii (Benth.) Kuntze

Abstract

In Tucumán, there are aromatic native populations with therapeutic properties like Aloysia gratissima (Gill. et Hook) Tronc, Chenopodium mandonii Willd. and Clinopodium gilliesii (Benth.) Kuntze. The last two share ecological niche and grow between 2,200 and 4,500 masl. Aloysia gratissima and C. mandonii are required for their digestive properties. Clinopodium gilliesii stands out for its antifungal and antioxidant potential. The objective of this work was to characterize genetically and reproductively A. gratissima, C. mandonii and C. gilliesii. Materials came from Tafí del Valle (Tucumán). Traditional cytogenetic techniques of mitosis, meiosis and pollen grain viability to evaluate reproductive potential were used. Results revealed for A. gratissima a 2n=54 with irregularity in meiosis and 92.4% of pollen inviability. These values were similar to those of C. gilliesii, but the chromosomal number was not confirmed in the last case because of its size (0.2 μ approx.). Chromosomes at diakinesis indicate it could be a polyploid with x=5, infertile. In C. mandonii meiosis was regular, with 2n=54 and 93.4% of pollen viability. The situation found in C. mandonii refers to an evolution process of diploidization that explains the regularity in meiosis and the good seed germinating power, useful condition for the conservation of its germplasm. In the other two species, clonation tasks aimed to the preservation of their genetics must continue.