An efficient estimation of crop performance in sheep fescue (Festuca ovina L.) using artificial neural network and regression models.

Festuca ovina L. (sheep fescue), a perennial grass plant found in mountainous regions, is important from both an ecological and economic viewpoint. However, the variability of biological yield of sheep fescue due to its reliance on different characteristics makes it difficult to accurately prediction using classic modeling techniques. In this study, machine learning methods and multiple regression models (linear and non-linear) are used to investigate the interdependence of various morphological and physiological characteristics on accurate prediction of the biological yield (BY) of sheep fescue. Principal components analysis and stepwise regression were used to select six agronomic parameters i.e. thousand seed weight (TSW), relative water content (RWC), canopy cover (CC), leaf area index, number of florescence, and viability (VA), while the output variable was BY. To optimized the artificial neural network (ANN) structure, different transfer functions and training algorithms, different number of neurons in each layer, different number of hidden layers and training iteration were tested. The accuracy of the models and algorithms is analyzed by root mean square error (RMSE), mean absolute error (MAE), and determination coefficient (R2). According to the findings, ANN models were more accurate than regression models. The ANN model with two hidden layers (i.e. structure of 6-4-8-1) which had RMSE, MAE and R2 scores of 0.087, 0.065 and 0.96, respectively, was discovered as the best model for predicting the BY. In addition, result of the sensitivity analysis showed TSW, RWC and CC, in that order, were the variables most important for high-quality BY estimation in both models regardless of input combination. Finally, the paper concludes that early flowering sheep fescue genotypes with long maturation and great TSW must be regarded as the most suitable model for increasing BY in breeding projects.

Determining Effective Environmental Factors in the Distribution of Endangered Endemic Medicinal Plant Species Using the BMLR Model: The Example of Wild Celery (Kelussia odoratissima Mozaff., Apiaceae) in Zagros (Iran).

Kelussia odoratissima Mozaff. is a medicinal species native to Iran. The goal of this research was to determine the environmental factors important for the distribution of K. doratissima in Iran using BMLR modeling. Six random transects were established throughout the species' habitat, and 220 quadrats with an area of 4 m2 were plotted. The canopy cover percentages of K. doratissima were estimated in each quadrat. Topographic factors, including elevation, slope, and aspect maps, were generated by creating DEM images. Land use, land evaluation, evaporation, temperature, and precipitation maps of the area were created accordingly. The data collected from the experiments were analyzed using the Minitab and R statistical packages. To determine the effect of the studied factors in the distribution of K. doratissima, we ran a set of backward multiple linear regressions. The results showed that the effects of evaporation, elevation, and slope were significant in the species' distribution, with elevation having a positive effect and evaporation and slope showing negative effects. Further, elevation had the highest effect on distribution (greatest absolute value of beta at 9.660). The next most significant factors in the plant's distribution were evaporation (beta = 8.282) and slope (beta = 0.807), respectively.

Phytoremediation ability of H. strobilaceum and S. herbacea around an industrial town.

Contaminations of soil and water resources with various organic and inorganic compounds are of great importance on account of the close relationship between the living organisms and their feeding. That is due to direct impact in supplying food for living organisms in terms of environmental and human health aspects. In this regard, the present study aimed to investigate the phytoremediation potential of H. strobilaceum and S. herbacea in contaminated soils. For this purpose, soil and plant samples were collected from around the sewage channel in Eshtehard industrial region of Iran. Sampling started at the edge of the channel and ended in a distance of 500 m from the channel. The distance of 1000 m from channel was considered as the control point. ICP-OES was used for the measurement of heavy metals. The obtained results showed that the highest and lowest amounts of soil lead (Pb) were 17.6 and 2.33 mg kg-1, respectively. For Cadmium (Cd), the values ranged from 0.341 to 0.11 mg kg -1 at 21-50 cm depth for the control point. For the plants, the highest and lowest amount of Pb belonged to H. strobilaceum shoot (10.38 mg kg -1) and S. herbacea root (7.54 mg kg -1), respectively. The maximum (1.64 mg kg-1) and minimum (0.36 mg kg-1) Cd concentration was observed in the root and shoot of H. strobilaceum, respectively. In both species, Translocation Factor (TF) for Pb and Cd was greater than 1 and less than 1, respectively. Cd Bio Concentration Factor (BCF) in the roots of both species was estimated to be greater than 1 while for Pb, this index was smaller. Bio Accumulation Factor (BAF) in the shoots of Pb and Cd for both plants were lower and greater than 1, respectively. In general, the results revealed that the highest concentrations of Cd and Pb are absorbed and stored by the underground organs of H. strobilaceum and S. herbacea and these plants have the ability to remove Pb and Cd from contaminated soils.

Chemical composition, antimicrobial, antioxidant and cytotoxic activity of the essential oil from the leaves of Stachys pilifera Benth.

Stachys pilifera Benth is an endemic species of Stachys family found in Iran with a wide application as an herbal tea. The objective of this research was to evaluate the antimicrobial, antioxidant and cytotoxic activity of the essential oil from the aerial parts of S. pilifera. Essential oil (EO) composition analysis showed that cis-Chrysanthenyl acetate (24.9%), viridiflorol (18.3%), trans-Caryophyllene (9.8%), caryophyllene oxide (4.6%), α-terpineol (3.3%) and linalool (3.1%) were the most abundant components. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the EO showed a higher antimicrobial activity against Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) than Gram-negative organisms (Escherichia coli, Shigella sonnei, Pseudomonas aeruginosa and Salmonella enterica subsp. Enterica). The antioxidant activity of EO was studied using DPPH, FRAP and ß-carotene/linoleic acid assays. IC50 for the DPPH, FRAP and ß-carotene/linoleic acid tests were 23.2, 28.7 and 16.1 µg/mL, respectively, that it was higher than the results for BHT (P ≤ 0.05). The cytotoxic activity of the EO was evaluated using HT29 and HUVEC cells and it was observed that by increasing in EO concentration from 0.026 to 19.4 ug/mL, the viability of the cells for HT29 and HUVEC reduced to 6.8 and 7.1%, respectively. The results from this study suggest the possibility to use the essential oils from S. pilifera Benth as a natural preservative in processed or packaged food due to its high antibacterial, antioxidant and cytotoxic activities.

Essential oil variability in Stachys pilifera Benth populations: a narrow endemic species of Iran.

Stachys pilifera Benth is an endemic species of Iran where it is found in the mountainous habitats of Zagros region. The plant is a rich source of secondary metabolites endowed with different medicinal properties. Here, for the first time, the essential oil variability among eleven wild populations of S. pilifera, was investigated. Results indicated that the variation of the chemical profile of essential oils was remarkable. The most abundant components were cis-chrysanthenyl acetate (19.1-48.2%), viridiflorol (1.4-19.1%), trans-caryophyllene (2.3-11.9%), caryophyllene oxide (1.9-11.0%), limonene (2.0- 5.9%) and spathulenol (0.0- 9.5). Based on the cluster analyses (CA), four main chemotypes were recognized: chemotype I (cis-chrysanthenyl acetate), chemotype II (cis-chrysanthenyl acetate/viridiflorol), chemotype III (cis-chrysanthenyl acetate/viridiflorol/spathulenol), chemotype IV (cis-chrysanthenyl acetate/trans-caryophyllene/α-pinene). The chemical variation detected can be useful to consider these populations for pharmaceutical industries and industrial applications as well as for domestication and conservation purposes.