In this study, the effects of altitude and soil properties on the essential oil amounts and essential oil components of the Turkish sage (Salvia fruticosa Mill.) plant were investigated. A location in the south of Turkey in the Kaş district of Antalya with altitude ranges of 0-200 m, 300-500 m, and 600-800 m was defined as the study area. During the full flowering period of S. fruticosa, plants and soil samples were collected. The contents of the essential oils of the plants were analyzed using GC-MS. According to theresults obtained, the essential oil content of plants varied between 1.91% and 5.10%. The main component of the essential oils of the plants collected from all study areas was 1,8-cineol, at 44.93%. It was concluded that variations in the proportions of the components limonene and linalool, which are essential oil components of plants, are not only dependent on altitude but also on changes in soil texture and the total CaCO3 content of the soil.

Origanum onites L., which is native to the Mediterranean region, is among one of the economically significant medicinal and aromatic plants that are not only gathered in the wild, but also cultivated in our country. The purpose of this study was to determine how the region in which Origanum onites grows affects the amount of essential oil and essential oil components in the plant's flowers and leaves. In this context, the effect of the plant's growing location on the essential oil content and essential oil components of the flowers and leaves of the Origanum onites, which grows naturally between 0-100 m in the Serik-Aksu, Demre, and Kaş regions of Antalya, was investigated together with the soil properties. The essential oils were extracted from the plant samples' leaves and flowers using the hydrodistillation method. The analysis of essential oils was done using gas chromatography-mass spectrometry (GC-MS) systems. Soil samples were analyzed for their pH, EC, CaCO3, texture, organic matter, total N, available P, and K values. The organic matter and exchangeable potassium contents of the soils, as well as the content of essential oil in the flowers and leaves of the plants, were found to increase gradually towards the west of Antalya. It has been demonstrated that the amounts of essential oil components of the plants varied depending on the region in each of the three different study locations.

With the development of technology, analysis methods have also increased and, as with many products, the properties of essential oils can be studied using methods based on electrical properties. In this study, the electrical properties of lavender essential oil mixed with various fixed oils were to be investigated to determine the adulteration rate more quickly and easily. Corn oil, olive oil, and sunflower oil were selected as fixed oils to obtain the oil samples with different adulteration rates. In this context, the real and imaginary parts of the permittivity, the loss tangents, the electrical conductivities, the amplitudes, and the phases of the impedances of the oil samples were measured. The measurements were also used to create an equivalent Debye circuit model for the lavender essential oil in order to analyze its electrical properties. The results showed that the lavender essential oil and the oil samples mixed at different rates showed different results in terms of electrical properties at different frequencies. According to the measurements, electrical conductivity was a critical parameter for a mixture of pure lavender essential oil and corn oil. The loss tangent was investigated for the mixture of pure lavender essential oil and olive oil, and the mixture of pure lavender essential oil and sunflower oil. It was observed that the electrical conductivity in the studied frequency band increased when the adulteration rate in the mixed corn oil samples increased. In addition, the loss tangent of the olive oil mixture and the sunflower oil mixture increased as the adulteration rate of said oil samples increased. By measuring the electrical properties, it may be possible to determine whether there is an adulteration and dilution process for particularly valuable essential oils, and if so, in what proportion.

The goal of this study is to investigate the variations in certain quality parameters, including total antioxidant activity, total phenol and total flavonoid contents, of various organs, including inflorescences, leaves and stems, of the Satureja thymbra plant, which grows naturally in the Kaş district of Antalya. Also, the relationship between these quality parameters and the nutrient content of the plant was revealed. The free radical (DPPH) was used to determine the antiradical scavenging activities of extracts prepared from various parts of the plant. The concentration of the antioxidant compound that can cause a 50 % loss in DPPH free radical activity is expressed by the IC50 value. S. thymbra leaf extracts have higher antiradical scavenging activity (IC50 = 0.11 mg dw/mg-DPPH), total phenol (38.79 mg GAE/g), and total flavonoid (29.0 mg/g) content than extracts of other plant components.

In this study, the germination performance of Asclepias curassavica L. seeds under salinity and drought stress, as well as their effects on radicle and plumule, were investigated. For the salinity stress experiment, solutions were prepared using 6 different NaCl at 0, 50, 100, 150, 200 and 250 mM. To simulate drought stress, six distinct levels of water stress were created using polyethylene glycol-6000 (PEG 6000) solutions with varying water retention capacities, encompassing 0, -2, -4, -6, -8, and -9.8 bar. Germination trials were carried out with 20 seeds in each petri dish according to the random plots experimental design with four replications. In order to examine the germination performances of the seeds, the petri dishes in which the solutions to create the stress conditions were applied and the seeds were placed were tested for 15 days in a controlled germination cabinet with a constant ambient temperature of 20°C, 70% humidity, 14 hours of light, and 10 hours of dark conditions. According to the results obtained, in salinity stress applications, the germination rate of Asclepias curassavica L. seeds ranged from 100.00% to 5.00%; the radicle length varied between 34.34 mm and 2.65 mm; the plumule length ranged from 35.11 mm to 8.11 mm; the fresh weight of the radicle fluctuated between 9.38 mg and 0.70 mg; and the fresh weight of the plumula varied from 20.25 mg to 5.88 mg. In drought stress treatments, the germination rate of Asclepias curassavica L. seeds ranged from 100.00% to 65.00%; radicle length ranged from 33.86 mm to 5.89 mm; plumule length ranged from 23.86 mm to 10.04 mm; radicle fresh weight ranged from 8.95 mg to 2.53 mg; and plumule fresh weight ranged from 15.55 mg to 5.58 mg. The study indicates that low to moderate salt levels did not hinder the germination of Asclepias curassavica seeds, but salt stress could lead to a reduction in radicle and plumule growth, resulting in disproportionate development of the plants. Additionally, it was concluded that the germination of Asclepias curassavica seeds was preserved under drought stress up to a certain level, with root and shoot growth increasing compared to plants that were not exposed to stress. These findings highlight the species' ability to adapt under stress conditions.

The research occurred in a plastic greenhouse in the autumn season between 2022-2023 and 2023-2024. Lettuce was grown in the greenhouse with organic agriculture-origin fertilizers. The cos type lettuce cultivar ‘Presidential’ was used. The aim was to evaluate the effects of various fertilizer applications, including seaweed, vermicompost, humic-fulvic acid, and a control, on lettuce yield and quality. Fertilizers were applied to the soil in liquid form at the recommended rates for lettuce production. The study revealed significant variations in several parameters across applications. Total yield ranged from 21.42 to 43.75 t ha-1, while market yield varied between 20.50 and 41.33 t ha-1. Marketable plant weight ranged from 410.00 to 826.67 kg plant-1, while the average plant weight was between 428.33 and 875.00 kg plant-1. Additionally, the number of discarded leaves ranged from 5.00 to 24.33 units. The SPAD value showed a range of 27.18 to 38.30, while water-soluble dry matter (WSDM) and dry matter values varied between 0.80-4.90% and 3.63-10.15%, respectively, depending on the applications. The study found that the applications generally yielded better results than the control application. In addition, the highest yield and plant weight were observed in lettuce plants treated with seaweed fertilizer.