Micropropagation of chokeberry by in vitro axillary shoot proliferation.

The black chokeberry-aronia (Aronia melanocarpa Elliot) is a shrub native to North America although nowadays well known in Eastern Europe. The fruits are regarded as the richest source of antioxidant phytonutrients among fruit crops and vegetables. Chokeberries can be easily propagated by seeds but this method is not recommended. Micropropagation is far more efficient than other conventional cloning methods like layering or softwood cuttings. Aronia clones are propagated in vitro through four- or three-stage method based on subculturing of shoot explants. The double diluted MS or full strength MS medium with elevated 50% Ca(2+) and Mg(2+) content are used in the initiation and proliferation chokeberry in vitro cultures, respectively. They are supplemented with 0.5-1.0 mg LBA, and 0.05 mg LIBA. The double-phase medium is recommended in the last passage before shoot rooting. The regenerated shoots could be rooted both in vitro on double diluted MS with 0.05 mg L(-1) IBA or in vivo in peat and perlite substrate and subsequently grown in the greenhouse.

Fabrication of left-handed metal microcoil from spiral vessel of vascular plant.

Silver microcoil is fabricated through a biotemplating process combined with electroless plating. Spiral vessels in Lotus root are employed as a biotemplate because of their left-handed coil structure. The silver microcoil exhibits a solenoidal microcoil showing self-inductance in the level of picohenry, which could be applied for electromagnetic-responsive materials in the high-frequency region such as millimeter waves or terahertz waves.

Cryopreservation of Fraser photinia (Photinia x fraseri Dress.) via vitrification-based one-step freezing techniques.

An efficient vitrification-based cryopreservation procedure was developed for Fraser photinia shoot apices by assessing the influences of various vitrification solutions (PVS1, PVS2, PVS3 and VSL) and different vitrification methods (cryovial vitrification, droplet vitrification and droplet freezing) on shoot regrowth. Moreover, influences of cold-hardening period (0 to 8 weeks), preculture medium (with sucrose and proline) and regrowth medium (QL plus 4.4, 8.8 and 17.6 micromolar BA) were also evaluated. Among the different procedures tested, best shoot regrowth (40.3 percent) was achieved by using a droplet vitrification technique in which cold-hardened and precultured shoot apices were vitrified for 120 min at 0 degree C in droplets, rapidly cooled, thawed and then cultured on 17.6 micromolar BA-containing QL medium. Overall results indicated the importance of not only the composition of vitrification solution, and preculture and regrowth media, but also the application of an appropriate vitrification technique to achieve optimum recovery post-cryopreservation.