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Transgenic walnuts (Juglans regia L.) were produced in the presence of the Agrobacterium strain LBA4404 and the plasmid pBI121. This plasmid contains a BADH gene driven by a CaMV 35S promoter. It f...

Allicin is a sulfur compound found in genus Allium characterized by numerous biological and pharmacological properties. Melanocrommyum, the second largest subgenus of Allium, has about 10 sections and 82 species in Iran. In this study, allicin content of aerial part, aerial part fresh mass and allicin yield belonging to 17 wild populations of six species of Allium sect. Acanthoprason and Asteroprason growing in different region of Iran, were analyzed. Allicin content evaluation using HPLC method showed its variation between populations from 26.98 to 58.11 mg g-1 FW, also showing that all the tested populations of Allium are rich in allicin. The average of aerial part fresh mass and allicin yield varied between populations from 0.49 g to 1.66 g and from 14 mg to 78 mg, respectively. The populations were classified in four major groups using dendrogram generated by UPGMA method of cluster analysis. However, grouping of populations was not completely related to species and geographical regions. This study is the first evaluation of allicin content in wild populations of Allium sect. Acanthoprason and Asteroprason in Iran. High amount of allicin in these populations make them a new sources of allicin.

Light emitting diodes (LEDs) now enable precise light quality control. Prior to commercialisation however, the plant response to the resultant light quality regime ought to be addressed. The response was examined here in chrysanthemum by evaluating growth, chlorophyll fluorescence (before and following water deficit), as well as stomatal anatomy (density, size, pore dimensions and aperture heterogeneity) and closing ability. Plants were grown under blue (B), red (R), a mixture of R (70%) and B (RB), or white (W; 41% B, 39% intermediate spectrum, 20% R) light LEDs. Although R light promoted growth, it also caused leaf deformation (epinasty) and disturbed the photosynthetic electron transport system. The largest stomatal size was noted following growth under B light, whereas the smallest under R light. The largest stomatal density was observed under W light. Monochromatic R light stimulated both the rate and the degree of stomatal closure in response to desiccation compared with the other light regimes. We conclude that stomatal size is mainly controlled by the B spectrum, whereas a broader spectral range is important for determining stomatal density. Monochromatic R light enhanced stomatal ability to regulate water loss upon desiccation.

Transgenic walnuts (Juglans regia L.) were produced in the presence of the Agrobacterium strain LBA4404 and the plasmid pBI121. This plasmid contains a BADH gene driven by a CaMV 35S promoter. It further includes an NPTII gene as a selectable marker which, in turn, is driven by a NOS promoter. Somatic embryos of the walnut cultivar ‘Chandler’ were inoculated using an Agrobacterium suspension. Secondary embryos that developed on a selection medium were driven towards germination so as to develop micro-shoot cultures. The regeneration rate was 5.5%. PCRand southern blot analysis were used for confirming that the BADH transgene is successfully integrated into the plant genome. Transgenic and wild-type plants raised from somatic embryos were exposed to four osmotic stress levels (i.e. 0%, 2%, 4%, and 8% PEG) and four salinity levels (i.e. 0, 50, 100, and 200 mM NaCl). After 21 days, the transgenic plants grew almost vigorously in saline and drought-stress conditions, whereas the wild-type ones showed retarded levels of growth and did not survive after the cradle stage. These results show that the BADH gene can be expressed effectively in transgenic plantlets of walnut and can be used for breeding walnuts against drought and salinity.

Common basil is well known for its aromatic and medicinal properties. This study was aimed to investigate effects of light spectrum on essential oil composition, antiradical activity and to...

Mastali H, Zare-Mehrjerdi M, Norouzi M, Rezaei J. 2018. Karyomorphological variations in some populations of Allium subgenus Melanocrommyum section Acanthoprason in Iran. Biodiversitas 19: 720-725. Allium is the largest genus of Amaryllidaceae comprising more than 900 species belonging to 15 subgenera. Iran is reported to be a center of diversity for subgenus Melanocrommyum. Acanthoprason is a section in this subgenus. In this paper, karyomorphological variations of nine populations of four species including Allium derderianum, A. kurdistanicum, A. minutiflorum and A. subakaka of the section Acanthoprason growing in Iran were undertaken using squash technique and 2% (w/v) aceto-orcein stain. All of the populations have the same chromosome numbers 2n = 2x = 16 with the exception in Kochka population of A. derderianum 2n = 18. In the present study, the chromosome number of A. minutiflorum and new chromosome number of A. derderianum were revealed for the first time. Chromosomal characteristics were determined using photographs complemented by cluster analysis. According to dendrogram generated by the unweighted pair-group method with arithmetic average (UPGMA) cluster analysis, nine populations studied were separated into five groups at a cut off value of 5. Karyotype analysis indicated that Allium species studied here generally have metacentric and submetacentric chromosomes and symmetric karyotypes. Results of the present study revealed the natural variation in nine populations of four species of Acantoprason section which can further serve conservation and breeding planning.

Endogenous signals in response to exogenous factors determine the senescence of flowers. Interactions among phytohormones especially abscisic acid (ABA) and ethylene are the major determinant of the senescence. In the present study, complex expression patterns of the genes related to ABA and ethylene as endogenous signals were investigated on cut carnations (Dianthus caryophyllus L.) that were exposed to different light spectra. Expression of ethylene biosynthetic (DcACS and DcACO), and signaling (DcETR and DcEin2) genes and also genes involved in ABA biosynthesis (DcZEP1 and DcNCED1), transport (DcABCG25 and DcABCG40) and catabolism (DcCYP707A1) were evaluated in petals of carnations exposed to three light spectra [white, blue and red]. Lowest relative membrane permeability (RMP) was detected in flowers that exposed to Blue light (BLFs), as a consequence, the longest vase life was found in BLFs. The Red and White lights markedly accelerated flower senescence and increased expression of DcACS and DcACO on day 6 and 10 of vase life assessment respectively; while Blue light inhibited the expression of ethylene biosynthetic genes. Expression of the genes involved in the production and transport of ABA and in signal transduction of ethylene was elevated during vase life of flowers irrespective of exposure to different light spectra. In conclusion, Blue light can be an effective environmental factor to extend the vase life of carnation flowers by delaying the petal senescence through down-regulation of ethylene biosynthetic genes and up-regulation of ABA biosynthetic genes.

Carnation is an important cut flower with industrial and medicinal applications. To establish an efficient protocol without somaclonal variation for micropropagation of Dianthus caryophyllus, direct and indirect somatic embryogenesis (DSE and ISE) were investigated under six different light spectra (white, red, green, blue, red + blue and far red + red) and four combinations of different plant growth regulators (PGRs) never tested so far for carnation. The best results were achieved with 2,4-dichlorophenoxyacetic acid (2,4-D) + N-(2-chloro-4-pyridyl)-N′-phenylurea (4-CPPU) for ISE and picloram + 4-CPPU or naphthoxyacetic acid (NOA) + 6-benzylaminopurine (BAP) for DSE. The DSE method was faster (3 weeks compared to 8 weeks) and easier (no subculturing compared to two rounds of subculture with ISE methods) but the percentage of somatic embryos in the ISE method was higher compared to the DSE method. Our results showed that the highest DSE, formation of embryogenic callus, embryo maturation (generation of globular, heart and torpedo shapes) and ISE rate was observed in carnation explants exposed to blue light (450–495 nm). In contrast, green (495–570 nm), red (610–700) and far red (710–730 nm) lights caused negative effects on embryogenesis compared to white light controls (380–750 nm). For the first time, genetic stability of regenerated carnation plants was estimated using inter-simple sequence repeat (ISSR) markers. The amplified products showed 75 distinct and scorable bands, and regenerants [plants obtained by primary (PSE) and secondary SE (SSE)] were completely identical to the mother plant. Similarly, flow cytometric analysis confirmed that somatic embryo-derived plants had on average 1.53 pg nuclear DNA (2C), and all plants maintained their ploidy. In conclusion, obtained embryos under blue light were big in size and torpedo-shaped and their germination was highest compared to other light spectra. Moreover, blue light was effective for direct and indirect somatic embryogenesis in carnation without induction of somaclonal variation. An effective protocol through application of phytohormones is introduced. Blue light can be used to improve in vitro propagation of carnation by somatic embryogenesis. Genetic stability of regenerated carnation plants was confirmed using inter-simple sequence repeat (ISSR) markers.

Garlic is known for its capacity to accumulate sulfur (S) and selenium (Se) in its bulbs. Therefore, it is a brilliant plant crop for S and Se biofortification and enrichment of consumers' diet with these elements. However, environmental and consumer concerns may limit mineral biofortification of plant crops by chemical fertilizers. This study investigated the effects of using a natural source of S, gypsum (0, 20, and 40 ppm S in the soil) and foliar application of Se (0, 15, and 30 ppm Se) on mineral biofortification of two of Iranian garlic ecotypes (Gorgan and Ramhormoz). After 40 days, the plants were harvested and their mineral composition and bioactive compounds were evaluated. In both ecotypes, the use of S with low Se concentration increased antioxidative capacity of the bulbs. Simultaneous application of S and Se resulted in the highest concentration of total phenolics in both ecotypes. Effect of application of selenium and sulfur on flavonoids' concentration in the bulbs of the ecotypes was different. Gorgan ecotype had the highest flavonoids' concentration under low sulfur concentration, while Ramhormoz ecotype obtained the highest flavonoids following application of high concentrations of S and Se. In both ecotypes, the highest content of allicin was found in high S but with low Se levels. Moreover, in parallel with increasing of S and Se levels, concentration of these elements increased in both ecotypes. The highest concentrations of selenium and sulfur in the bulbs (969.9 μg kg−1 DM and 1.97 mg g−1 DM, respectively) were observed in high S combined with high Se in Gorgan ecotype. Therefore, this study demonstrated the possibility of improving the nutritional value of garlic by simultaneous application of gypsum and Se foliar spray.

Light spectrum of growing environment is a determinant factor for plant growth and photosynthesis. Plants under different light spectra exhibit different growth and photosynthetic behaviors. To unravel the effects of light spectra on plant growth, photosynthetic pigments and electron transport chain reactions, purple and green basil varieties were grown under five different light spectra including white (W: 400–730 nm), blue (B: 400–500 nm), red (R: 600–700 nm) and two combinations of R and B lights (R50B50 and R70B30), with same PPFD (photosynthetic photon flux density). Almost all values for shoot and root growth traits were higher in purple variety and were improved by combinational R and B lights (especially under R70B30), while they were negatively influenced by B monochromatic light when compared to growth traits of W-grown plants. Highest concentration of photosynthetic pigments was detected in R70B30. Biophysical properties of photosynthetic electron transport chain showed higher florescence intensity at all steps of OJIP kinetics in plants grown under R light in both varieties. Oxygen evolving complex activity (F(v)/F(o)) and PSII maximum quantum efficiency (F(v)/F(m)) in R-grown plants were lower than plants grown under other light spectra. Values for parameters related to specific energy fluxes per reaction center (ABS/RC, TR(o)/RC, ET(o)/RC and DI(o)/RC) were increased under R light (especially for purple variety). Performance index was significantly decreased under R light in both varieties. In conclusion, light spectra other than RB combination, induced various limitations on pigmentations, efficiency of electron transport and growth of basil plants and the responses were cultivar specific.

Artemisinin represents medicinally employed compound of Artemisia annua (L.) and is widely used against a num- ber of diseases. This study presents the effect of an exogenous application of salicylic acid (SA) and gibberellic acid (GA3) on the expression of genes coding for artemisinin pathway enzymes as well as on the biosynthesis of artemisinin. We found a temporary increase in artemisinin content in A. annua leaves 12 h after SA application. However, the transcript levels of all studied genes coding for artemisinin pathway enzymes decreased throughout the period studied and artemisinin content dropped down to an even lower level than in control plants at 168 h after treatment. In addition, artemisinin content increased, together with up-regulation of genes coding for en- zymes of artemisinin biosynthesis pathway, owing to GA3 application. However, down-regulation of all investi- gated genes was also observed at 72 h after treatment, probably due to the negative feedback control. As can be seen, both SA and GA3 exogenous applications can increase artemisinin accumulation in different ways. Because of a temporary increase in artemisinin content after SA or GA3 application, it is critical to determine the best harvesting time. Future research should focus on removing the negative feedback mechanism to achieve high- yield Artemisia plants.

Artemisinin, produced in very low amounts in Artemisia annua L. plants, is one of the most effective drugs in treating malaria. In this study, the effect of exogenous applications of methyl jasmonate (MeJA) and 2-isopentenyladenine (2-iP) in artemisinin production and the main genes of its biosynthesis pathway within a 1-week time period were investigated. Both MeJA and 2-iP increased artemisinin content, but no correlation was found between gene expression and its content. In plants treated with 2-iP, despite increased gene expression following elicitor application, downregulation of gene expression was also observed, which might be attributed to the negative effects of rising artemisinin levels in gene expression. In plants treated with MeJA, the steady increase in artemisinin content was not explained by the few changes observed in gene expression, suggesting that some other mechanism may increase artemisinin. Our results indicate that the negative feedback mechanism of artemisinin is likely an obstacle for the selection of biotechnological strategies to increase artemisinin content. This may be overcome by studying the role of trichome in artemisinin production as a step toward achieving high yields of this valuable component.