Genetic diversity of different ecotypes from three Althaea species using SCoT phytochemical and molecular markers

Althaea genus belongs to the Malvaceae family. Althaea officinalis is the most important species of this genus for medicinal use. Other species, such as A. rosea and A. ficifolia, also have medicinal uses. Different flower organs (flower, fruit, seed, root, and leaf) of Altheae species have many medicinal uses due to high mucilage, phenolic compounds, and antioxidant properties. This research aims to find the best ecotypes for the investigated phytochemical traits. It also aims to determine the distance and genetic similarity between the studied Altheae species ecotypes. It is intended to be used in various projects.

The research was carried out in 1401 in the research greenhouse, the agriculture and medicinal plants laboratory, and the genomics laboratory in the Aburihan Faculty of Agricultural Technology (Tehran University) located in Pakdasht city at 51 degrees east longitude and 33 degrees north latitude. It was conducted at 1013 meters above sea level and 36 kilometers southeast of Tehran. In this research, the molecular diversity and phytochemical traits of total phenol content, mucilage content, and antioxidant capacity were investigated in 9 ecotypes of three species of Altheae species. In the phytochemical evaluation, extracts were obtained from the roots by the Soxhlet method. Evaluation of molecular diversity was done after extracting DNA from leaves by the CTAB method using 10 SCoT primers. The quality and quantity of the extracted DNA were evaluated using two methods a spectrophotometer and horizontal electrophoresis on 1% agarose gel.

In the phytochemical evaluation, it was found that in terms of total phenol, the Kermanshah ecotype had the highest value statistically, with 10.67 mg of gallic acid per gram of extract. Regarding the amount of mucilage, the Kermanshah and Kerman ecotypes were ranked first in the same group with 2.86 and 2.77 mg per gram of dry weight, respectively, compared to other ecotypes. Pearson's correlation coefficient was calculated between phytochemical traits. It was determined that there was a positive and strong relationship between the traits evaluated in the experiment. Evaluation of molecular diversity was done after extracting DNA from leaves by the CTAB method using 10 SCoT primers. A total of 111 bands were formed, and 76 were polymorphic bands. PIC values varied between 0/22 and 34%. The percentage of polymorphism in this research varied between 0/5 and 0/87, and its average was 0/67. The average MI and RP indices were 1/55 and 5/48, respectively. In cluster analysis of molecular data, ecotypes were divided into three groups with 70% similarity. The dendrogram obtained from cluster analysis of ecotypes shows genetic similarity between ecotypes belonging to the same species. It also shows the genetic distance between ecotypes related to different species. The results of decomposition into principal coordinates also confirmed cluster analysis results. In the analysis of molecular variance, it was found that 27% of the variation was within species, and 63% was between species.

In the end, it was found that SCoT phytochemical and molecular markers have the necessary efficiency to differentiate different ecotypes of Altheae species. Due to genetic diversity, to improve this plant, the ecotypes examined in this research can be crossed as the initial population and parents.