Mutation breeding techniques have been used to induce new genetic variations and improve agronomic traits in soybean. In Korea, the Korea Atomic Energy Research Institute (KAERI) has unique radiation facilities to induce plant mutations and has been conducting soybean mutation breeding programmes since the mid-1960s. Until now, the KAERI has developed five soybean mutant cultivars exhibiting early maturity, high yield and seed-coat colour change. In this paper, we review these five mutant cultivars in terms of how to successfully induce unique agronomic characteristics through mutation breeding programmes. A number of induced mutants exhibiting null lipoxygenase enzymes, altered protein patterns or Kunitz trypsin inhibitor activity could serve as genetic resources for the genetic analysis of target genes, and one mutant population has been developed for a reverse genetic study.

Blackberry is a fruiting berry species with very high nutrient contents. With the recent increasing consumer demand for blackberries, new sources of germplasm and breeding techniques are required to improve blackberry production. This study was carried out to evaluate the genetic diversity (GD) and relationship among 55 blackberry (Rubus fruticosus) mutants derived from γ-ray treatment (52 lines) and N-methyl-N′-nitrosourea (MNU) treatment (three lines) using an inter-simple sequence repeat marker. A total of 18 bands were amplified with an average of 3.6 bands per primer. Among them, eight bands were identified to be polymorphic with a rate of 44.4%. In addition, the GD information content values were highest in the 60 Gy treatment population and the GD values were higher in the γ-ray treatment populations than in the MNU treatment population. According to a cluster analysis, all the mutant lines can be classified into five categories, and the genetic distance was greatest between the 80 Gy-irradiated population and other populations. These results indicate that mutant lines have high GD and can be effectively utilized for improving blackberry breeding.

The effects of polymer substrates on the interfacial structure and the thermal stability of Ga-doped ZnO (GZO) thin films were investigated. The GZO thin films were deposited on polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) substrates by rf-magnetron sputtering at room temperature, and thermal stability tests of the GZO thin films on the polymer substrates were performed at 150°C up to 8 h in air. Electrical and structural characterizations of the GZO thin films on the PET and the PEN substrates were carried out, and the origins of the stable interfacial structure and the improved thermal stability of the GZO thin film on the PEN substrate were discussed.

Using immunostaining methodology, we traced the axonal projection of FMRFamide (Phe-Met-Arg-Phe-NH2)-like immunoreactive (LI) medial neurosecretory cells (MNCs) and lateral neurosecretory cells (LNCs) from the brain into the ventral nerve cord (VNC) and retrocerebral complex in Bombyx mori (L.) (Lepidoptera: Bombycidae). Of the seven pairs of FMRFamide-LI MNCs, one pair extended its axons from the brain pars intercerebralis into the VNC ipsilateral connective where they appeared to terminate. The axons of the remaining MNCs ran through decussation in the brain median region and contralateral nervi corporis cardiaci (NCC) I out of the brain, and eventually innervated the contralateral corpus cardiacum (CC). Axons from the single pair of FMRFamide-LI LNCs projected into the ipsilateral NCC II fused with NCC I without decussation in the brain, and finally terminated in the CC. These results suggest that transport of the FMRFamide-like neuropeptide from may be related to the modulation of functions such as gut contraction in MNCs terminating in the VNC, and regulation of production and/or secretion of specific hormones such as juvenile hormone in MNCs and LNCs terminating in the CC.

A novel route to organic-inorganic composites was described based on biomineralization of poly(ethylene glycol) (PEG)-based hydrogels. The 3-dimensional hydrogels were synthesized by radical crosslinking polymerization of poly(ethylene glycol fumarate) (PEGF) in the presence of ethylene glycol methacrylate phosphate (EGMP) as an apatite-nuclating monomer, acrylamide (AAm) as a composition-modulating comonomer, and potassium persulfate (PPS) as a radical initiator. We used the urea-mediated solution precipitation technique for biomineralization of hydrogels. The apatite grown on the surface and interior of the hydrogel was similar to biological apatites in the composition and crystalline structure. Powder x-ray diffraction (XRD) showed that the calcium phosphate crystalline platelets on hydrogels are preferentially aligned along the crystallographic c-axis direction. Inductively-coupled plasma mass spectroscopy (ICP-MS) analysis showed that the Ca/P molar ratio of apatites grown on the hydrogel template was found to be 1.60, which is identical to that of natural bones. In vitro cell experiments showed that the cell adhesion/proliferation on the mineralized hydrogel was more pronounced than on the pure polymer hydrogel.

By injecting additional argon gas, we were able to grow one-dimensional ZnO nanorod arrays with a uniform distribution on a large scale at a low temperature of less than 330 °C by metalorganic chemical vapor deposition. All of the nanorods grown on the sapphire substrate had a 30° in-plane rotation with respect to the substrate and showed the epitaxial characteristics of [10¯10]ZnO//[11¯20]sapphire, despite the low-temperature growth. These ZnO nanorods with high crystalline quality exhibited a high enhancement factor and low turn-on field value, thus having good potential to be used as a field emitter.