In vitro study on regeneration of Gladiolus grandiflorus corm calli as affected by plant growth regulators

In this study, in vitro organogenesis of Gladiolus grandiflorus cultivar pink corm segments were evaluated by culturing corm calli in modified MS medium supplemented with 3% sucrose and 0.7% agar with different concentration of BAP (0, 1, 2 and 4 mg L(-1) medium) and NAA (0, 0.5, 1 and 2 mg L(-1) medium) in factorial experiment of Completely Randomized Design (CRD). In order to obtain Gladiolus calli, corm segments (Aprox. 5 x 5 x 1 mm in size) were kept in modified MS medium (Murashige and Skoog, 1962) that was supplemented with 1 mg L(-1) 2, 4-D, 3% sucrose and 0.7% agar. The results showed that increasing the concentration of BAP from 0 to 2 mg L(-1) medium simulated plantlet regeneration but no significantly effect was obtained on shoot and cormel organogenesis between 2 and 4 mg L(-1) BAP concentration in medium. Increasing of NAA content in media without BAP developed rootlet significantly. Interaction results showed that increasing BAP content against decreasing of NAA concentration stimulates the shoot and cormel proliferation.     

Bluetongue virus: virology, pathogenesis and immunity

Bluetongue (BT) virus, an orbivirus of the Reoviridae family encompassing 24 known serotypes, is transmitted to ruminants via certain species of biting midges (Culicoides spp.) and causes thrombo-hemorrhagic fevers mainly in sheep. During the 20th century, BTV was endemic in sub-tropical regions but in the last ten years, new strains of BTV (serotypes 1, 2, 4, 8, 9, 16) have appeared in Europe leading to a devastating disease in naive sheep and bovine herds (serotype 8). BTV enters into insect cells via the viral inner core VP7 protein and in mammalian cells via the external capsid VP2 haemagglutinin, which is the major determinant of BTV serotype and neutralization. BTV replicates in mononuclear phagocytes and endothelial cells where it induces expression of inflammatory cytokines as well as apoptosis. BTV can remain as nonreplicating entities concealed in erythrocytes for up to five months. Homologous protection against one BTV serotype involves neutralizing antibodies and T cell responses directed to the external VP2 and VP5 proteins, whereas heterologous protection is supported by T cells directed to the NS1 non structural protein and inner core proteins. Classical inactivated vaccines directed to a specific serotype generate protective immunity and may help control current epidemic situations. New recombinant vaccine strategies that allow differentiating infected from vaccinated animals and that generate cross protective immunity are urgently needed to efficiently combat this worldwide threatening disease.     

Modulus of elasticity in scarf-jointed wooden beams: a case study with polyvinyl acetate and isocyanate adhesives

In the present study, elastic properties of scarf-jointed oak (Quercus castaneifolia) timbers with the application of two different types of adhesives (polyvinyl acetate and isocyanate) were evaluated using free flexural vibration of free–free beam method in different flexural directions of vibration, i.e., tangential and redial directions. Samples were taken from trees of Hyrcanian forests in Iran with nominal dimensions of 20 × 20 × 360 mm³. Comparing the results of elastic properties of clear oak wood beams with scarf-jointed samples wood showed that scarf joints with the bonding angles of 70° and 75°, covered by polyvinyl acetate adhesive, did not demonstrate any significant effect on modules of elasticity. Scarf-jointed beams with smaller joint angles (60° and 65°) were considerably weaker or totally unreliable in their moduli of elasticity. It is also shown that the magnitude of effect gets worst by using isocyanate rather than polyvinyl acetate adhesive.     

Combining ability analysis of resistance to head blight caused by <Emphasis Type="Italic">Fusarium graminearum</Emphasis> in spring wheat

Fusarium head blight (FHB) caused by Fusarium spp. is one of the most important fungal diseases of wheat (Triticum aestivum L.) in regions with wet climatic conditions. Improvement of the FHB resistance by developing new varieties requires sound knowledge on the inheritance of resistance. An 8 × 8 diallel analysis was performed to estimate general (GCA) and specific (SCA) combining ability of resistance to FHB. The F₁s and parental lines were evaluated under artificial inoculation at the experimental field of IFA-Tulln, Austria during 2001 and 2002. Disease severity was evaluated by repeated scoring of the percentage of infected spikelets and calculating an area under the disease progress curve (AUDPC). The analysis of combining ability across two years showed highly significant GCA and non-significant SCA effects indicating the importance of additive genetic components in controlling FHB resistance. The significant GCA-by-year interaction presented the role of environmental factors in influencing the FHB reaction of wheat lines. The comparison of the crosses with low FHB infection and GCA effects of their parents showed that such crosses involved at least one parent with high or average negative GCA effect. The results revealed that it is feasible to use highly or moderately resistant genotypes and conventional breeding methods to achieve genetic improvement of FHB resistance in spring wheat.     

Properties of PP/wood flour/organomodified montmorillonite nanocomposites

In this research, composites based on polypropylene (PP), beech wood flour, and organomodified montmorillonite (OMMT) were prepared and characterized for their properties. The blend nanocomposites were prepared by melt mixing of PP/WF at 50% weight ratios with various amounts of OMMT (0, 3, and 6 per hundred compounds (phc)) in a Hakee internal mixer. Then the samples were made by injection molding. The influence of organomodified montmorillonite contents on clay dispersion, physical and mechanical properties of PP/wood flour composites were investigated. Results indicated that the flexural strength and modulus, tensile strength and modulus increased by addition of 3 per hundred compounds (phc) of organomodified montmorillonite (OMMT), but decreased with 6 phc OMMT addition. However, impact strength, water absorption and thickness swelling of the composites decreased with increasing nanoclay loading. X-ray diffraction patterns (XRD) and transmission electron microscopy (TEM) revealed that the nanocomposites formed were intercalated. Also, morphological findings showed that samples containing 3 phc of OMMT had higher order of intercalation.     

Effect of Winter Planting Date on Oil Yield and Fatty Acids of New Spring Canola (Brassica napus L.) Cultivars Under Foliar Zinc Spray

Canola (Brassica napus L.) oil yield and fatty acid composition are the function of genotype, climate conditions, morphology, and physiology as well as crop management. In this study, the reaction of different canola cultivars—in terms of seed oil content and fatty acids—to different planting dates and foliar zinc application during two experimental years (2016–2017) was investigated in the field in arid and semi-arid regions of Karaj, Iran. The experiment was performed as a factorial split plot in a randomized complete-block design with three replications. Three sowing dates (February 9, 19, 29) and two foliar zinc applications (non-application as control and zinc application; spraying in the stem elongation stage) were factorially randomized to main plots, and canola cultivars (Sarigol, Dalgan, Salsa, and Solar) were allocated to sub-plots. The results indicated that the effect of year, planting date, zinc application, cultivar, and the interaction effect of planting date and cultivar on quality traits (glucosinolate and fatty acids) and seed yield were significant (p?<?0.01). The delay in winter planting of spring canola cultivars caused a significant reduction in seed yield, oil yield, and the content of oleic, linoleic, and palmitic fatty acids and increased the content of linolenic, erucic, stearic, arachidic, and behenic fatty acids and glucosinolate. The highest seed yield (4732.2?kg/ha), oil yield (2066?kg/ha), and oleic acid content (66.52%) were observed in the Dalgan cultivar in the zinc application treatment with normal planting date (February 9). The Salsa cultivar had the highest content of erucic acid (0.46%) and glucosinolate (17.3?μmol/g meal) in the control treatment with the last planting date. Because the quality of edible canola oil depends on the increase in unsaturated fatty acids, particularly oleic and linoleic acids, and the reduction of erucic acid and glucosinolate, planting Dalgan cultivar with zinc application at the normal planting date is recommended for the study area and similar areas.

     

Localization of herpes simplex virus type 1 DNA in latently infected BALB/c mice neurons using in situ polymerase chain reaction

Background: Herpes simplex virus type-1 (HSV-1) establishes a lifelong latent infection in neurons following primary infection. The existence of latent HSV-1 DNA in the trigeminal ganglia of infected BALB/c mice was examined using a direct in situ PCR technique, based on Digoxigenin-11-dUTP detection system with anti-digoxigenin-peroxidase and 3,3''-diaminobenzidine (DAB) substrate. Methods: Eight-week-old male BALB/c mice were inoculated via the eye by 10⁴ plaque forming unit of wild type Iranian isolates of HSV-1. After establishment of latency, trigeminal ganglia were removed and examined using in situ PCR to detect HSV-1 genome. Finally, the results of in situ PCR were verified by a two-round PCR method, using amplification cocktail of in situ reaction, as a template for a conventional gel base PCR. Results and Conclusion: The results suggest that a direct in situ PCR method using a peroxidase and DAB detection system is a useful means for detection of latent HSV-1 DNA in the latently infected ganglia. Key Words: Herpes simplex virus-1, Latency, In situ PCR, two-round PCR, Trigeminal ganglia     

Zygosity identification in transgenic cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis>) by real-time quantitative PCR

Successful identification of homozygous and heterozygous transgenic plant with currently available techniques such as southern blot hybridization, dot blot hybridization, fluorescence in situ hybridization (FISH) and so on, demands tedious and time-consuming procedures with a high proportion of ambiguous results. Real-time PCR is a quantitative and extremely precise method with high throughput that could be applied to the analysis of large number of plants differing only by a factor of two in the amount of target sequences. In the present study, we determined zygosity level of transgenes in cotton [Gossypium hirsutum L.] with two zygosity assays, based on TaqMan technology that uses a fluorogenic probe which hybridizes to a PCR target sequence flanked by primers. TPS, a single copy gene per haploid Gossypium hirsutum genome was used as the endogenous reference to estimate copy number of transgene. Both assays were accurate and reproducible in determination of the number of transgenes present in a cell line. These methods are standard curves and Delta delta C _t method.     

Diterpenoid (poly)esters and a ring A-seco-phorboid from the aerial parts of Euphorbia macroclada Boiss

Euphorbia macroclada Boiss., a spurge endemic to the Iranian plateau, afforded four pre-myrsinane polyesters, three α-phorboids and one A-seco-phorboid, a type of compound so far unreported within natural products. All new compounds were structurally elucidated by spectroscopic methods, and especially 2D NMR measurements.