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The present study was carried out to evaluate aerial yield, agronomic traits, essential oil production, and their relationships in 21 populations of Ziziphora tenuior in Karaj, Iran over two years (2016–2017). The experimental layout was a randomized complete block design with three replications. Data were collected for GDD (Growth Degree Days), plant height, canopy area, stem number, flower number, aerial fresh yield, aerial dry matter (DM) yield, seed yield, essential oil percentage and oil production. The essential oil compositions were detected in accession 2929 (Tassoj) using GC/MS. Result of combined analysis of variance across two years showed significant differences between years, populations and population x year interaction for all traits (P < 0.01). In comparisons among populations, the population of Avaj and Ijroud with average values of 13.5 and 14.33 g/p had higher aerial dry yield and other agronomic traits followed by Meshkin2 and 3. For seed yield, Ormieh with average values of 3.11 g/p had higher production. For oil content, the populations of Tassoj, Salmas and Sharkord with average values of 1.25 to 1.56% had higher oil content and essential oil production. Result of correlation analysis showed that DM yield was positively correlated with GDD, plant height, canopy area, stem number, flower number. Oil content was negatively correlated with aerial DM yield. The results of PCA analysis showed that the first four components accounted for 50, 20, 12 and 10% of the total variation, respectively. Plant height, canopy area, stem number, flower number and aerial yield in the PCA1, essential oil content and oil production in the PCA2, seed yield in the PCA3 and GDD in PCA4 components were identified as important traits. Using Ward cluster method, the 21 populations were grouped into 3 clusters. In total, 23 compounds were identified in the essential oil from the aerial parts Z. tenuior. The major components in the essential oil were pulegone ranged (47.54 to 65.26%) followed by neo-iso-dihydro carveol, carvacrol, piperitenone, limonene, 1.8-cineole, p-mentha-3,8-dien, alpha-terpinene and terpinen-u-ol. It was concluded that there were wide range of variations for agronomic trait and essential oil in domestic germplasm of Z. tenuior to improved breeding new varieties in Iran.

Abstract Background Buxus hyrcana (boxwood) is an endangered species in the Hyrcanian forests in the north of Iran. This tree is threatened by habitat loss but faces additional threats from the introduced disease the boxwood blight (caused by the fungus Calonectria pseudonaviculata syn. Cylindrocladium pseudonaviculatum, Cy. buxicola) and the potential effects of climate change. As wide range of genetic polymorphism is necessary to ensure successful adaptation to rapid climatic changes. Methods Genetic diversity and differentiation between 15 healthy and 15 infected trees of each of two populations were studied using RAPD and ISSR molecular markers. Results High-band polymorphism was found in pooled samples of B. hyrcana using both ISSR (58%) and RAPD (73%) markers. The ISSR data and the combined data set classified the trees into two groups. However, data from RAPD clustered the trees into three groups. These results indicate different degrees of genetic variation in the sequences of the tested B. hyrcana genomes targeted by the two marker types used. Genetic variation was found to be relatively high, with most of the diversity occurring within populations. Analyses of healthy versus infected pooled samples based on both marker types indicated that genetic diversity parameters were mostly higher in healthy trees. Conclusions Boxwood blight has had a major effect on B. hyrcana, killing individual stems quickly especially in dense populations and reducing population size (as observed in all populations). Considerable within-population diversity, and higher genetic variability in healthy trees than infected ones, suggested conservation efforts should focus on survivor trees in each population and consider the establishment of tree reservations. Propagation of plants from seeds is preferred, since it would include the widest range of genetic variation.

Ageing induces seed deterioration expressed as the loss of seed vigor and/or viability. Priming treatment, which consists in soaking of seeds in a solution of low water potential, has been shown to reinvigorate aged seeds. An experiment was conducted to evaluate the effects of naturally and accelerated aging on seed germination traits and enzyme activities (proxidase, catalase and superoxid dismutase) in three Achillea vermicularis accessions. Naturally aged seeds were provided from base (stored 10 or15 years at -18 °C) and active (stored 10 or 15 years at 4 °C) cold rooms of Natural Resources Gene Bank of Iran. A two years harvested seeds of the accessions were aged under moisture of 100% and temperature of 40 °C for 48 and 72 hours. The seeds were primed by incubation for 24 hours at 15 °C in solution of polyethylene glycol 6000 (PEG6000) −0.3 Mpa (as osmo-priming), gibberellic acid 250 and 500 ppm (as hormone-priming). Non-primed seeds were used as control. ANOVA suggested significant different among three accessions of A. vermicularis for all germination traits and enzymes activities. Results showed that responses of different accessions to aging and priming treatments were significantly different. The data demonstrated that catalase is a key enzyme for seed repair against ageing ROS-induced damage during priming treatment.

The Achillea L. genus has a wide distributional range, and the differences in oil composition may be affected by different environmental factors such as soil mineral fertilization, the climate conditions and the culture site. To evaluate the effect of temperate climate on content and chemical combination of essential oil of Achillea filipendulina Lam, A. arabica Kotschy and A. eriophora DC., this study was carried out.Essential oils were analyzed by GC and GC/MS. Yield of essential oil of A. filipendulina, A. arabica and A. eriophora cultivated was 0.9, 2.25 and 2.3%, respectively .The major components of A. filipendulina were santolina alcohol (37.2%), borneol (12.7%),1,8- cineole (8.7%), germacrene D (6.22%), and camphor (4.09%). In A. arabica, the major compounds were p-cymene (14.61%), piperitone (13.09%), camphor (12.81%) and 1, 8-cineole (11.97%). In A. eriophora, principal compounds were camphor (19.57%), 1, 8-cineole (19.06%), camphene (9.61%) and α-pinene (7.35%). Our results demonstrate variations in the qualitative and quantitative composition in the oils obtained from the aerial parts of the studied species. Also, chemical profile of A. filipendulina was slightly affected under temperate climatic conditions, suggesting its ability and flexibility to be cultivated in temperate zones.

Fifteen yarrow populations from different species Achillea millefolium L., A. biebersteinii L. and A. nobilis, from different geographical areas of Iran were studied using 24 morphological traits and peroxidase profiles. Comparison of mean values of different phenotypic traits show A. millefolium and A. biebersteinii L. had higher plant height and crown diameter; however, A. nobilis had higher dry matter yield and 1000-grain weight. Clustering pattern, made on the basis of different phenotypic traits, grouped the Achillea populations differently and gave no clear indication of origin or species. The results of peroxidase profiles revealed that the genetic diversity of A. nobilis samples was considerably higher than in A. millefolium and A. biebersteinii. Principal coordinate analysis revealed a clear separation between the different Achillea species. The results demonstrated that the study of genetic diversity and relationships among Achillea species using phenotypic traits and peroxidase profiles provides important information for the collection, conservation and the planning of future breeding programs.