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Abiotic and biotic elicitors may induce higher synthesis of bioactive compounds in medicinal plants. In the present study, the impact of salicylic acid (SA) and cellulase from Aspergillus niger (CE) elicitors with 200 mg/L concentration at 24, 48 and 72 h treatment durations was evaluated on total phenolic and flavonoid contents and Withaferin A and Withanolide A compounds (analyzed by HPLC) as well as free radicals scavenging activity in cell suspension culture derived from leaf and stem explants of Withania coagulans (Stocks) Dunal for the their production in commercial level. The results of this investigation revealed that all elicitors treated cell cultures obviously promoted total phenol content (TPC), total flavonoid content (TFC), Withaferin A and Withanolide A accumulation as well as antioxidant activity. Also, these characteristics increased as treatment duration of SA and CE elicitors enhanced in both leaf and stem cell extracts and reached a maximum at 72 h treatment duration. In most treatments, TPC and TFC of leaf cell extracts did not have significant difference with TPC and TFC of stem cell extracts. In contrast, the leaf cell extracts had higher Withaferin A and Withanolide A amounts when compared to stem cell extracts under all treatments. The highest values of TPC, TFC, Withaferin A, Withanolide A, and antioxidant activity observed in SA elicitor treated leaf cell extracts at 72 h treatment duration (1.61-fold, 2.46-fold, 3.08-fold, 1.99-fold, and 1.78-fold higher than control culture, respectively). Therefore, elicitation can be applied as a promising strategy for large-scale production of W. coagulans valuable secondary metabolites in cell suspension culture at commercial level. [ABSTRACT FROM AUTHOR]

The climate has drastically changed over the past two decades. Rising temperatures and climate change may lead to increased evapotranspiration, specifically soil evaporation, causing water to evaporate and salt to accumulate in the soil, resulting in increased soil salinity. As a result, there is a need to evaluate methods for predicting and monitoring the effects of salinity on crop growth and production through rapid screening. Our study was conducted on 20 wheat genotypes, 10 sensitive and 10 tolerant, exposed to two salinity levels (90 and 120 mM NaCl) with the control under greenhouse conditions. Our results revealed significant differences in the genotypes' response to salinity. Salt stress decreased chlorophyll index in sensitive genotypes but increased chlorophyll a and carotenoids in tolerant genotypes at 90 mM. Salt stress also increased protein, proline, lipoxygenase, and reactive thiobarbituric acid levels in all wheat genotypes. The study suggests that plant photosynthetic efficiency is a reliable, non-destructive biomarker for determining the salt tolerance of wheat genotypes, while other biochemical traits are destructive and time-consuming and therefore not suitable for rapid screening. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana Bert. is a medicinal plant used as a calorie-free sweetener due to the presence of steviol glycosides in its leaves. The present study evaluated morphological, biochemical, and molecular changes of stevia under salicylic acid (SA) elicitors (0, 25, 50, 75 and 100 µM) and yeast extract (YE) (0, 1, 2, 3 and 5 g/L) under in vitro conditions. The results showed significant effects of elicitors on morphological traits and photosynthetic pigments of stevia. The highest morphological traits were observed at 25 µM and control treatments of SA and YE respectively. On the other hand, increasing the concentrations of both elicitors resulted in lowered morphological traits. In general, plants treated with YE showed lowered growth, with the concentration rise lowering the growth further. HPLC results showed an increase in steviol glycosides content in 50 µM SA and 2 g/L YE treatments and then the highest amount of stevioside and rebaudioside A was at concentrations of 25 µM and 3 g/L. Investigation of expression levels of four genes (KA13H, UGT74G1, UGT76G1, and UGT85C2) indicated that the highest rate of expression occurred at the concentrations of 50 µM SA and 2 g/L of YE. While, control treatment had the lowest levels expression of the studied genes in both elicitors, which indicates the significant effect of elicitors compared to the control. These results demonstrate the significant effect of SA and YE at medium concentrations on levels of expression of key genes of biosynthetic pathway as well as the production of stevioside and rebaudioside A. Thus, this approach could be employed to elevate the steviol glycosides' levels under in vitro conditions. [ABSTRACT FROM AUTHOR]

EXPOSED TO MN STRESS Keywords: Barley; Genome Wide Association Analysis; Manganese; Morphological Traits; QTL EN Barley Genome Wide Association Analysis Manganese Morphological Traits QTL INTRODUCTION In agricultural systems, plant productivity is strongly influenced by environmental conditions. The objectives of this study were (1) to evaluate genomic regions affected Mn stress and contributive morphological traits in a diverse spring barley collection, (2) to establish marker-trait associations for each trait, and (3) to identify genes/loci affecting Mn stress in spring barley that can be used for genetic improvement in breeding programs. The manganese toxicity symptoms vary widely among plant species and varieties within species, perhaps because the phytotoxic mechanisms of Mn involve different biochemical pathways in different plant genotypes (El-Jaoual and Cox, 1998). [Extracted from the article]

Differentiation among populations of the Iranian Teucrium polium L. was analyzed on the basis of morphological and phytochemical variability, to evaluate the level and distribution of diversity among four distant populations from arid, semi-arid, and subhumid regions of Fars Province. Morphological analysis included 11 characters related to the plant, leaf, and stem morphology. Analyses of variances and clustering were done to establish the variability and significance of morphological differentiation. The morphological analysis of plants from the studied populations confirmed that the species belonged to malacophyllous xeromorphic species and were distinguished by stable conservative xeromorphic characteristics. Morphological variation was correlated with ecological conditions at the site of origin and there was a small difference between the plants belonging to arid and semi-arid populations and the sub-humid ones. Chemical analysis was performed using combination of capillary GC, GC-MS after fractionation on column chromatography. The chemical composition of their oil differed qualitatively and quantitatively between the populations. β-Caryophyllene was the major oil compound in the sub-humid and semi-arid populations, while the main compound of arid populations were farnesene-cis-b and linalool. In addition, oil samples from semi-arid and sub-humid populations contained β-bisabolene (1.6-2.2%), myrcene (0.9-1.1%), bornyl acetate (0.7- 0.8%), and 3-octanol (0.6-0.8%), which were not detected in oil samples from arid populations. All oil samples, however, were dominated by hydrocarbon compounds. The relatively low morpho-chemical diversity in the populations indicates that the maintenance of their evolutionary potential is at risk if population sizes are not maintained and if there is no protection of the habitats. [ABSTRACT FROM AUTHOR]

The population of this research included 167 recombinant inbred lines (RILs) derived from a Seri/Babax cross. In order to map and visualize the genetic architecture of the agricultural traits, an experiment was conducted in an alpha lattice under normal (2 ds m−1) and saline (12–14 ds m−1) conditions at the Research Farm of Agricultural and Natural Resource Station of Zabol, Iran for 2 years (2012–2013). in this study, a total of 20 QTLs with additive effects and of 24 QTLs with epistatic effects for these traits were identified and distributed across all 21 chromosomes of wheat. Twenty stable QTL regions were detected on chromosomes 1B, 1D, 2A, 3B, 4A, 6A, 7A and 7D, which could significantly affect traits in all experiments. The QTLs detected on chromosomes 7D and 1D were not only significant and consistent but also co-localized for days to heading and days to anthesis. Several colocalized and additive QTLs with variability in QTL regions of chromosome 3B were also identified, which included the QTLs for final dry biomass (BY, straw + grain), grain yield and water-soluble carbohydrate content. The only two QTLs on chromosome 1B identified for the two traits were chlorophyll Florence (FV/FM) and thousand grain weight in different regions. Most of the identified QTLs had significant additive and epistatic effects with QTL and environments (QEIs) interactions. [ABSTRACT FROM AUTHOR]