The Study of Vegetative Traits and Oil Components in Three Populationa of Ziziphora clinopodioides L. in Esfahan

Lamiaceae is a large plant family with many important genus like Ziziphora. This genus has four species in Iran. Three species including Z. tenuior, Z. persica and Z. capitata are annual and Z. clinopodioides is Perennial. Ziziphora clinopodioides Lam. is an aromatic plant that leaves and flowers are frequently used as a traditional herbal medicines for the treatment of colds and cough. In Iran, this plant is mostly used in traditional medicine as a sedative, carminative, anti-emetic, anti-inflammatory and antiseptic substance in food. The present work was conducted to investigate the reaction of different plant populations to cultivation in one place.

The experiment was conducted during 2017-2019 in Fozveh station of Agricultural and Natural Resource Research Center of Isfahan. It was on the basis of randomized complete block design with three replications. Treatments were three populations of Z. clinopodioides that were collected from Isfahan province including Makooleh, Sarcheshmeh Golpayegan and Daran regions. Measured traits included: dry shoot weight, plant height, dry to wet weight ratio, 1000-seed weight, essential oil percentage, yield of essential oil and essential oil compounds. The percentage of essential oil was measured in 50% flowering stage by using hydro-distillation using an all-glass clevenger apparatus for 4 h. The amount of essential oil compounds was measured by gas chromatography (GC) and the qualification of essential oil was measured by gas chromatography-mass spectrometry (GC-MS). The chemical compounds of the essential oil were identified on the basis of GC-MS retention time on fused silica capillary column and by comparison between their retention indices (RIs) with retention indices of published data, Standard Mass Spectral Fragmentation Pattern. Sas 9.1 software package was used for data analyses. Mean and standard deviations of each experiment were calculated and then were subjected to analysis of variance. Duncan test was used to determine mean differences among the treatments at 1% probability. Also, interactions were analyzed by using MSTATC software.

The combined analysis results showed a significant difference for all traits among populations. Sarcheshmeh Golpayegan and Daran populations had the highest (179 and 7011 kg.ha-1) and lowest (70 and 6120 kg.ha-1) seed yield and aerial dry yield respectively. Also the highest amount of oil percentage and oil yield were observed in Sarcheshmeh Golpayegan population. The range of essential oil percentages between populations were from 1.2% (makooleh) to 1.4% (sarcheshmeh). Experimental years had a significant effect on all studied traits except of 1000-seed weight. Populations in the second year had higher performance than the first year. This was especially noticeable in shoot dry weight, seed yield and essential oil yield. Results of genotype*year interaction revealed that Sarcheshmeh Golpayegan population had the highest seed yield and shoot dry weight in the second year. In total, 26 compounds were identified in Z. clinopodioides essential oil populations. Two major identified compounds in essential oil analysis recognized as 1,8 cineole and polegone. In Makoole population Polegone was the main component but Sarcheshmeh Golpayegan and Daran were rich in 1, 8- Cineole.

In general, the results of this study indicated that the studied populations had the sufficient genetic diversity for various traits such as shoot yield, seed yield and essential oil percentage. The existence of this diversity can pave the way for remedial work in the future. This research has shown that Z. clinopodioides has the ability to adapt and cultivate in the field environments. Therefore, it can be used as a new medicinal plant in the country's agricultural system. This plant can also be introduced as an appropriate source to provide a combination of 1, 8- Cineole and Polegone used in food and pharmaceutical industries.