Response surface methodology (RSM) is one of the statistical methods for optimizing dependent variable in response to independent variables, and has been used in various field of food engineering. The model coded by RSM has a canonical formulation of 2nd order polynomial with the normalized ranges of independent variables. To accurately accomplish the optimization using RSM an adequate experimental design, i.e., response surface design, is necessary. Response surface design is determined by type of design and number of independent variables. In this study, we are to develop a response surface design applicable for optimizing hulled barley (Hordeum vulgare) production under various conditions of temperature and humidity in forage growing system. As a result, 3 experimental designs were conceived for future RSM; central composite design (CCD), inscribed central composite design (ICCD) and equiradial design. Each design requires experimental trials of 13, 13, and 8, respectively. We will further select one of the designs for actual experiments for finding the optimal temperature and humidity necessary for maximizing fresh forage production in the system.
In vitro high-frequency plant regeneration of Muscari comosum var. plumosum through somatic embryogenesis was obtained via two developmental pathways: direct embryos and multiple shoots regenerated from embryogenic callus. Flower bud with pedicel, receptacle, petal and ovary wall, floral stalk and leaf as explants were cultured in MS medium supplemented with various plant growth regulators. Embryos formed directly from pedicel, receptacle and floral stalk. Depending on explant sources, the optimal medium was MS medium supplemented with 0.2 mg/L IBA and 0.3 mg/L BA, 3.0 mg/L IBA and 3.0 mg/L BA, and MS-free medium for pedicel, receptacle, and floral stalk, respectively. Multiple shoots regenerated from embryogenic cal]i which was initiated from petal, ovary and leaf were observed in MS medium with different concentrations and combinations of hormone. The most suitable medium for each type of explant was 3.0 mg/L IBA and 3.0 mg/L BA(petal and ovary) and 5.0 mg/L IBA and 5.0 mg/L BA (leaf) Furthermore, the combination of 0.1 mg/L 2,4-D and 1.0 mg/L BA was also good for all sources of explants not only for direct embryo formation, but also, for embryogenic callus induction.
Transgenic Petunia hybrida cv. Rosanpion was produced by Agrobactepium tumefaciens LBA4404 harboring a binary vector pBI 121 containing β-glucuronidase (gus) and neomycin phosphotransferase (nptII). For genetic transformation, leaf discs were precultured on MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L BA (MNB) for 2 days and cocultured for 15 mins with A. tumefaciens. For selection of transformant, leaf discs were transferred to fresh MNB containing 50 mg/L kanamycin and 500 mg/L cefotaxime. Eighteen plants were regenerated and four were confirmed by PCR for detection of gus and nptII gene integrated into the nuclear genome of petunia ‘Rosanpion’. Using this transformation system, we expect that transgenic petunia ‘Rosanpion’ incorporating a useful gene can be produced.