In this study, 160 tea tree (Camellia sinensis L.) lines were classified by caffeine content using colorimetric methods. Among them, caffeine-rich lines (HR-78, HR-137, HR-82 and HR-123) and poor lines (HP-85, HP-88, HP-19, and HP-131) were selected. To know the difference in morphological and genetic characters between caffeine-rich and poor lines, we used leaf/shoot growth and RAPD methods. Cluster pattern of morphological characters (leaf width, leaf length, leaf area and shoot length) showed that shoot length was longer in caffein-rich lines than in -poor lines. In genetic analysis, amplified DNA bands having various sizes were detected in RAPD analysis where 30 random primers were used. However, the discriminated primer set that distinguish caffein-rich tree line from -poor lines was not found. These results can be used as the basic data to determine the morphological and genetic differences among caffein-rich and -poor lines
An efficient method for the rapid micropropagation of Camptotheca acuminata from axillary buds was established by application of various plant growth regulators. Among various cytokinins, 0.5 mg L-1 BA showed the best performance on shoot multiplication, number average multiple shoots up to 10.8. The propagated shoot cuttings in vitro were elongated on NN basal medium without plant growth regulators. The secondary multiple shoots were induced at the site of initially induced buds. Rooting was induced directly near the base of the shoot on half-strength NN medium containing 0.5 mg L-1 of IBA, whereas high concentration of 1.0 mg L-1 IBA could induce callus at the base of the shoot. The camptothecin content, anticancer compound of the micropropagated plants was contained in various tissues. Camptothecin contents were 1.8 and 2.5 mg g-1 dry weight in stems from propagated in vitro and mother plant, respectively. This result may be used to develop strategies for large-scale propagation of elite C. acuminata trees.
An efficient method for the rapid propagation of Smilax china from axillary buds was established. Plants with thick leafage were selected from Korea native S. china population. Axillary buds of S. china collected from selected plant and were cultured in various culture media (2MS, MS, 1/2MS, WPM, B5 and SH medium). Shoot was induced from axillary bud on MS basal medium after 4 weeks of culture. 1/2MS medium showed a higher growth rate than those of the others, while the lowest shoot growth was obtained in 2MS medium. Among the sucrose concentrations, 5% sucrose was the optimum level for shoots growth from axillay buds. Among cytokinins, 0.5 mg L -1 6-benzylaminopurine (BAP) treatment showed the best performance on shoot multiplication, yielding average shoot multiplication forming about 2.4. Rooting was induced directly near the base of the shoot on 1/2MS medium containing with three-auxins α-napthalene acetic acid (NAA), indole acetic acid (IAA) and β-indolebutyric acid (IBA) (0.5 and 1.0 mg L -1 ). The 1.0 mg L -1 IBA treatments induced earliest rooting with maximum of root number and root growth. These rooted plantlets were successfully transferred to pots for 4 weeks hardening process, and were transferred to soil with above 90% survival rate.
Korean soybean variety Kwangan was transformed with ORE7 gene using highly efficient soybean transformation system. The gene is known to exhibit a delayed leaf senescence phenotype in Arabidopsis. To confirm phenotypic characterization of leaf senescence for non-transgenic (NT) and transgenic plants, we transplanted T1 transgenic lines 7, 9, 14 and 15 together with two negative controls (NT and EV) in greenhouse. As a result, line 15 showed dramatic phenotypic characterization of yield increase and senescence delay. In addition, to investigate the agriculture traits for transgenic plants with leaf senescence delaying, T2 transgenic lines and two negative controls were transplanted on GMO fields in Ochang and harvested T3 seeds (2010). Most transgenic lines showed higher total seed weigh than NT. Especially, total seed weight of line 15 was increased by about 180% and 120% compared with the NT and EV, respectively. Therefore, we carried out the second field experiments with T3 transgenic line 15 and NT in Ochang (2011). A total of 117 transgenic plants were divided into two groups, senescence delaying (64 out of 117 plants) and increased yield (53 out of 117 plants), by transcript level of ORE7 gene. Interestingly, among increased yield plants, total seed weight of each 7 plants were increased by more than 200% compared with NT.
Effects of nitrogen (N), phosphorous (P) and potassium (K) on the shoot and bulb growth of wild garlic (Allium victorialis var. platyphyllum) were studied by adopting in vitro culture. These macronutrients influenced the growth of both the shoot and bulb of garlic depending upon their application doses. A minimum of 3% potassium nitrate (KNO3) as a source of nitrogen was found to be critical for shoot elongation while higher concentrations were inhibitory. Garlic bulb growth was profuse on the usual KNO3 strength and sucrose (7%), followed by KNO3 (9.4 mM) supplement. On providing 41.22 mM ammonium nitrate (NH4NO3) as nitrogen source highest shoot growth was observed while 82.45 mM NH4NO3 as a source of nitrogen supported high bulb growth. With regard to potassium a good shoot growth was observed in medium that contained 0.31 mM KH2PO4 and 3% sucrose, while bulb growth was high on 2.5 mM KH2PO4 and 7% sucrose. These experiments may thus direct the development of excellent growth conditions for the commercial production of edible wild garlic.