Transformation of Brazilian eliteIndica-type rice (Oryza sativa L.) by electroporation of shoot apex explants

We have generated transgenic plants of a Brazilian elite Indica-type rice by electroporation of shoot apices. This approach avoids a callus phase and produces 0.4–13.8% resistant plants. Transgenic plantlets were transferred to soil a few weeks after explant electroporation. Root segments from plantlets obtained from transformation experiments with pAHC25 plasmid were GUS positive. Integration of the introduced gene into the genome was demonstrated by PPT and antibiotic screening as well as by PCR and Southern blot hybridization of genomic DNA isolated from R₂ plantlets.     

Ribotyping of rhizobia nodulating Acacia mangium and Paraserianthes falcataria from different geographical areas in Indonesia using PCR-RFLP-SSCP (PRS) and sequencing

Acacia mangium and Paraserianthes falcataria are leguminous tree species widely grown for timber in Indonesia and other tropical countries, yet little is known about the identity of their rhizobial symbionts. Polymerase chain reaction-restriction fragment length polymorphism-single-strand conformational polymorphism (PRS) analysis of the 16S rRNA gene was used along with sequencing to assess the diversity of 57 rhizobia isolated from nodules of A. mangium and P. falctaria in Indonesia. In total, 26 rhizobia isolated from A. mangium were analysed by PRS and sequencing. The PRS patterns indicated that 12 (46%) clustered with Bradyrhizobium elkanii , 13 (50%) with B. lianoningense / japonicum and one (4%) with Mesorhizobium loti . Thirty-one isolates were analysed from P. falcataria : five (16%) clustered with B. elkanii and 26 (84%) with B. lianoningense / japonicum. These results were confirmed by phylogenetic analysis of sequences. Intraspecific diversity of the 16S rRNA genes from rhizobia nodulating A. mangium and P. falcataria revealed by PRS was low, only one genotype was found within the isolates that clustered with B. elkanii and two within the B. liaoningense / japonicum group. These Bradyrhizobium species are apparently ubiquitous throughout the Indonesian archipelago and it is clear why the two tree species are able to successfully establish outside their native range without the need for inoculation with indigenous rhizobia.     

Assessment of Genetic Stability Among In Vitro Plants of Arachis retusa Using RAPD and AFLP Markers for Germplasm Preservation

Arachis retusa Krapov. et W. C. Gregory et Valls is endemic in the West-central region of Brazil, occurring In areas endangered by human actions. The establishment of in vitro preservation methods for wild species of Arachis is an alternative to seed banks for germplasm storage, multiplication and distribution. The risk of genetic changes Induced by tissue culture and the monitoring of the genetic stability of the biological material before, during and after storage must be considered In the context of conservation. Random amplified polymorphlc ONA （RAPO） and amplified fragment length polymorphism （AFLP） fingerprinting were used to evaluate the genetic stability of in vitro plants originated from cotyledons and embryo axes of A. retusa. Cotyledons originated shoots through direct organogenesls and embryo axes displayed muItishoot formation Induced by 110 mmol/L and 8.8 mmol/L BAP, respectively. Ninety genomlc regions （loci） generated from RAPO and 372 from AFLP analyses were evaluated. All amplified fragments detected by both techniques in plants derived from the two explant types were monomorphic. The results Indicate that the recovered shoots are genetically stable at the assessed genomic regions.     

Action of growing degree days on the morphogenesis and physiological responses of calla lily

The calla lily (Zantedeschia aethiopica) is an ornamental plant with growing acceptance in the market place that shows thermal constraints during planting. This study aimed to analyse its biological cycle in growing degree days (GDD) to determine the best time for planting and production of flower stalks. Rhizomes were planted in pots during all four seasons, and the pots were kept in a greenhouse. Growth analysis and gas exchange measurements were performed every 30 days. Rhizomes planted in the fall and summer showed greater shoot growth, a larger root system and increased production of flower stalks, and they remained in the vegetative phase longer before the onset of flowering, attaining a lower GDD value. Rhizomes planted in winter and spring matured early, which resulted in a higher GDD value and a decrease or lack of flower stalk production during this period. Calla lily rhizomes planted in the fall and summer showed higher water-use efficiency, light-use efficiency and net photosynthesis. It is possible to characterise the stages of development according to gas exchange. The calla lily must be cultivated with an irradiance of 250–400 µmol m^?2 s^?1 in a temperature range of 25–28 °C during the initial growth phase (up to 1,000 GDD). Thereafter, the temperature range should be reduced to between 13 and 15 °C until 3,500 GDD are reached, which was found to enable increased flower stalk production.     

The role of BAP in somatic embryogenesis induction from seed explants of <Emphasis Type="Italic">Arachis</Emphasis> species from Sections <Emphasis Type="Italic">Erectoides</Emphasis> and <Emphasis Type="Italic">Procumbentes</Emphasis>

Somatic embryogenesis was induced from seed explants of Arachis archeri, A. porphyrocalix (Section Erectoides) and A. appressipila (Section Procumbentes) in response to 6-benzylaminopurine (BAP). Embryo axes first developed into single shoots in response to 4.4 μM BAP. Friable embryogenic calluses were produced from the hypocotyl region of these explants in response to different BAP concentrations. Embryonic leaflets also gave rise to friable calluses, but somatic embryos were only observed in explants of A. archeri and A. appressipila. Histological analyses revealed the presence of heart-shaped, torpedo and cotyledonary stages embryos, both as isolated and fused structures. A low frequency of embryo-to-plant conversion was achieved by inducing shoot development on medium solidified with 0.5% phytagel and supplemented with 1.5% or 3% sucrose. Rooting was induced on MS supplemented with indole-3-acetic acid (IAA).     

Resistance of grapevine to the erineum strain of Colomerus vitis (Acari: Eriophyidae) in western Iran and its correlation with plant features

The interaction of grape erineum mite (GEM), Colomerus vitis Pagenstecher (Acari: Eriophyidae), with grape was investigated in the laboratory. We studied some plant morphological biochemical features potentially related to vine resistance/tolerance of eight native grapevine cultivars, extensively cultivated in western Iran, and two non-native cultivars. Free-choice experiments indicated that the cultivars Shahani, Flame seedless and Yaghuti were colonized by lower levels of GEM, whereas Muscat Gordo, Gazne and White Thompson seedless hosted denser populations. These differences between cultivars may be due to differential attractiveness to GEM, possibly associated with plant biochemical and morphological traits. In no-choice assays with six grapevine cultivars, mite population development and some cultivar features were assessed. Mite populations grew fastest on Gazne and Muscat Gordo, and slowest on Yaghuti and Shahani. The degree of mite infestation was associated with reduction of leaf area, increase of leaf weight, shortening of shoots and more numerous erinea: these features were larger on the most infested Gazne, whereas morphological features of Shahani and Yaghuti were scarcely affected by GEM infestation. Also trichome type and density of the assayed cultivars appeared to be related to mite density: the most infested cultivars (Gazne and Muscat Gordo) displayed higher ranks of blade and vein hairs and lower ranks of blade and vein bristles and domatia. No correlation was found between mite density and leaf thickness of mature leaves. The amount of leaf waxes was highest in Shahani and Yaghuti, which displayed the lowest mite density, the fewest erinea and the largest leaves. Carbohydrate amount of uninfested leaves was lowest on the least infested Shahani and highest on the most infested Gazne; phenols increased in leaves of Shahani and decreased in those of Gazne after mite infestation. Finally, cultivars also appeared to influence some morphological traits of the mites: larger specimens were detected on White Thompson seedless, Flame seedless and Gazne, whereas smaller mites were found on leaves of the less infested Yaghuti and Shahani. These results indicate that leaf hairiness, leaf wax and carbohydrate contents may be useful tools for a preliminary screening among vine cultivars and help predict resistance/tolerance to GEM. Shahani and Yaghuti seem quite promising for developing grape resistance programs against GEM in western Iran.     

Deformity Correction in Ankle Osteoarthritis Using a Lateral Trans-Fibular Total Ankle Replacement: A Weight-Bearing CT Assessment

BackgroundAnkle osteoarthritis (AO) is often secondary to prior trauma and frequently presents with joint deformity. Total ankle replacement (TAR) has been shown as a viable surgical option to reduce pain, improve function, and preserve ankle joint range of motion. The standard TAR uses an anterior approach, but recently a lateral trans-fibular approach has been developed. Our aim was to determine if the lateral TAR was able to correct alignment and improve patient reported outcomes (PROs) in patients with end-stage AO.MethodsThis IRB-approved, retrospective comparative study included 14 consecutive patients that underwent lateral trans-fibular approach TAR for end-stage AO. All patients had received pre-and post-operative WBCT imaging on the affected foot and ankle. Using multiplanar reconstruction of WBCT images, measures of coronal and sagittal plane ankle alignment: Foot and Ankle Offset (FAO), Talar Tilt Angle (TTA), Hindfoot Moment Arm (HMA), and Lateral Talar Station (LTS) were performed. PROs were collected pre- and postoperatively at the latest clinical follow-up.ResultsAll patients demonstrated a significant deformity correction in all measurements performed: FAO (7.73%-3.63%, p=0.031), HMA (10.93mm – 5.10mm, p=0.037), TTA (7.9o-1.5o, p=0.003), and LTS (5.25mm-2.83mm, p=0.018). Four of the PROs measured exhibited significant improvement postoperatively, the Tampa Scale for Kinesiophobia (TSK) (42.7-34.5, p=0.012), PRO-MIS Global Physical Health (46.1-54.5, p=0.011), EFAS (5-10.3, p=0.004), and FAAM Daily Living (60.5-79.7, p=0.04). Multivariate analysis assessing the influence of deformity correction in the improvements of PROs found that PROMIS Global Physical Health was significantly associated with improvements in FAO and LTS, TSK associated with HMA, and FAAM Daily Living with FAO and TTA (p<0.05).ConclusionThe results of this retrospective comparative cohort study suggest that the lateral trans-fibular TAR can correct different aspects of AO deformity. The method also impacted PROs, particularly TSK, PROMIS Global Physical Health, EFAS, and FAAM Daily Living. Direct correlation between some of the deformity correction measurements and the significantly improved PROs was found. The obtained data could help surgeons when making treatment decisions and be the base for comparative prospective studies. Level of Evidence: III     

In vitro Osteogenic impulse effect of Dexamethasone on periodontal ligament stem cells

Periodontium is a complex organ composed of mineralized epithelial and connective tissue. Dexamethasone could stimulateproliferation of osteoblast and fibroblasts. This study aimed to assess the osteogenic effect of dexamethasone on periodentalligament (PDL) stem cells. PDL stem cells were collected from periodontal ligament tissue of root of extracted premolar of youngand healthy people. The stem cells were cultured in α-MEM Medium in three groups, one group with basic medium contains (α-MEM and FBS 10 % and 50 mmol of β_ gelisrophosphat and L_ ascorbic acid µg/ml), the second group: basic medium withdexamethasone and the third one: basic medium without any osteogenic stimulant. Mineralization of cellular layer was analyzedwith Alizarin red stain method. Osteogenic analysis was done by Alkaline phosphates and calcium test. These analysis indicatedthat the amount of intra-cellular calcium and alkaline phosphates in the Dexamethasone group was far more than the control andbasic group (P<0.05). The results of Alizarin red stain indicated more mineralization of cultured cells in Dexamethasone group(P<0.05). The study results showed that Dexamethasone has significant osteogenic effect on PDL stem cells and further studies arerecommended to evaluate its effect on treatment of bone disorders.