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In nature, plants are constantly challenged by an array of drought episodes, which critically affect the distribution of the plants. The drought episodes might occur recurrently, so the plants endure drought by adjusting and shifting their metabolisms. The impacts of subjecting plants to drought stress have been widely investigated, but reports on how reiterated drought stress affects the plants are limited. The present study was designed to investigate the response of lavender, a reputed medicinal and aromatic plant, against single drought, recovery and reiterated drought stress at greenhouse conditions. In this regard, the experimental design was based on three cycles of 11 days of drought by withholding water, followed by subsequent periods of 6 days of recovery, and then double-stressed and single-stressed periods. As expected, the present findings revealed that single stress decreased the fresh and dry weights of the leaf, stem and root. Reiterated drought stress caused critical reductions in the fresh weight of the leaf, stem and root, while the dry weight of stem and root were not significantly affected. Of the estimated traits, only the dry weight of leaf increased with reiterated drought stress. The mineral status of the leaves was adversely affected with single stress, but the effects of recovery and reiterated stress were not in accordance with the improvement in water contents of the leaf and soil. Regarding essential oil compounds, eucalyptol, camphor and endo-borneol were predominant. Single and reiterated drought stress increased camphor percentage, while recovery and full irrigation decreased the percentage. Endo-borneol was decreased under single stress, but reiterated stress increased the percentage of the compound. Considering the phenolic acids, stressed and non-stressed groups were well discriminated and hence, phenolic acids might be useful as good indicators of the stress response in lavender.

Among industrial crops, flax (Linum usitatissimum L.) is a multi-purpose crop grown for production of stem fiber and seed oil. Through longterm domestication for these purposes, cultivated flax has diversified into two main types, namely fiber and oil or linseed types, as well as an intermediate type. This study was designed to investigate the effect of flax fibers of flax varieties (Antares, Dakota and Mures) in field and greenhouse cultivation on fiber mechanical performances, morphological properties and fatty acid composition in flaxseed was investigated. Additionally, plants can change their morphology and mechanical properties when exposed to stress, as is particularly the case when plants respond to wind, a phenomenon known as seismomorphogenesis. Greenhouse plants were found to be significantly lower than field grown plants, with an increase of 16.79cm in technical stem length and 56.02cm in technical stem height. In addition, the total plant height of flax grown in the field was 59.33 cm compared to 17.32 cm in the greenhouse. The Mures variety was found to be the highest both in the field (79.50-76.10cm) and in the greenhouse (18.36-17.47cm). Considering the fatty acid percentages, the highest a-linolenic acid was found in Dakota (29.23%) and the lowest in Antares (20.53%) in the field, while the highest was found in Dakota (19.25%) and the lowest in Mures (16.13%) in the greenhouse. In addition, the highest tensile strength was found in Dakota (704.6 Mpa) and the closest Antares (692.2 Mpa) under field conditions, while the lowest was found in Dakota (198.5 Mpa) and Mures varieties (288.8 Mpa) under greenhouse conditions. In order to reduce the dimension, correlate and visualize the measured parameters, the relevant data of the study were subjected to principal component analysis and heatmap clustering. [ABSTRACT FROM AUTHOR]

Of the medicinal plants' cosmos, yarrow species (A. millefolium L. and A. wilhelmsii L.) are of the reputed species due to their phytochemical composition and thereby antioxidant and antibacterial activities. Owing to the high diversity in chemical composition and production of essential oil, the species deserves to be investigated more. In this context, wild yarrow plants were collected in Eastern Anatolia region (Van, Türkiye) and then the dried samples of the plants were subjected to hyd-rodistillation for essential oil extraction. In addition, the essential oils were assayed for their potential antioxidant and antibacterial activities. Gas Chromatography Mass Spectrometry (GC-MS) analysis revealed the presence of 1,8-cineole (75.19%), α-phellandrene (5.53%), P-eugenol (5.53%), camphor (5.45%), α-terpineol (2.09%), β-pinene (1.66%), camphene (1.20%), α-pinene(1.02%) from A. millefolium L. However, A. wilhelmsii was characterized with menthoglycol (35.84%), 1,8-cineole (34.04%), endo-borneol (9.93%), chrysanthenil acetate (4.76%), thymine (3.66%), terpinene-4-ol (2.33%), camphene (1.66%), and verbenole (1.53%). Regarding scavenging activities of the species, A. wilhelmsii exhibited better activity than A. millefolium, with a value of 6.5 mM and 4.2 mM Trolox equivalents (TEAC) respectively. With respect to the antibacterial activity against three gram-negative and three gram-positive bacteria, essential oils of both species were compared with standard antibiotic discs (ampicillin and ofloxacin). [ABSTRACT FROM AUTHOR]