Search Results

You are looking at 1 - 7 of 7 items for :

  • Author or Editor: Dong-Lim Yoo* x
  • HortScience x
Clear All Modify Search

This experiment was conducted to investigate the effects of artificial light sources for light period extension on growth and flowering of statice `Sophia' and `Early Blue'. The seeds were sown on 10 June in a plug tray with 128 plugs. The seedlings were grown at the highland (800 m above sea level) for 50 days, and transplanted on 30 July in 20-cm-diameter plastic pots. High-pressure sodium lamps (HPS) (220V, 400W), incandescent lamps (Il) (220V, 200W), and fluorescent lamps (Fl) (220V, 40W) for day length extension (16-h photoperiod) as compared with short day (8-h photoperiod) were tested. HPS gave the greatest photosynthetically active radiation (PAR), but Fl did the smallest. HPS or Fl as compared with Il showed high ratio of red/far-red light. The leaves of plant grown under HPS were effective for light absorbance and chlorophyll contents. HPS promoted photosynthesis as much as light period extension, while more respiration than photosynthesis occurred under Fl affected by low PAR. Long day condition as light period extension hastened flowering of statice, and HPS or Il were more effective than Fl on flowering among artificial light sources tested. The light compensation and saturation points of statice were 50 and 500 μmol·m–2·s–1, respectively. Photosynthesis hastened at high temperature, but amount of photosynthesis at vegetative stage showed much higher than flowering stage under the condition below 20 °C These results indicated that day length extension with HPS increased productivity and quality for cut flower of statice at the highland in Korea.

Free access

Iris hollandica `Blue Magic' was treated with deionazed water as a control, 3% sucrose (Suc), 3% sucrose plus 0.4 mm silver thiosulphate (Suc+STS), 3% sucrose plus 200 mg·L-1 8-hydroxyquinoline sulphate (Suc+HQS) and 3% sucrose plus 100 mg·L-1 benzyl amino-purine (Suc+BA) for 4hrs and then transferred to tap water. The vase life treated with Suc+BA was extended 4 days longer than that of control. The treatment Suc+STS or Suc+HQS did not improve vase life. The amounts of water uptake and transpiration by all treatments decreased after harvest, but those values were higher in cut iris treated with Suc+BA than in those with control. Cut flowers treated with by Suc+BA markedly improved water balance, comparing with control which was quickly changed to minus value. Anthocyanin content in petals of cut flower treated with Suc+BA was 3.5 fold higher than that of control. The treatment by Suc+BA delayed discoloration in petals and senescence of cut Iris. Peroxidase (POD) activities of all treatments were reached maximum at 4th day after treatment and decreased thereafter. POD activity was highest when the cut iris was treated with Suc+BA. These results show that the use of Suc+BA is most effective treatment for improving the vase life and quality of cut Iris flowers.

Free access

Hanabusaya asiatica has beautiful flowers as ornamental pot plant. It's a famous Korean endemic perennial plant in Korea. Recently many research items has been studying for developing cultivation technology of H. asiatica as a new commercial pot plant. Many endemic plants have much problems associated with maintaining quality for commercial plant. In H. asiatica, as a result of accumulation of anthocyanin in the leaves at reproductive stage, the leaf veins turn to brownish black and whole leaves become to necrosis and dry after all. This study was carried out to find out the suitable method for preventing the accumulation of anthocyanin in leaves by light quality. H. asiatica was treated three light quality, blue, far-red + blue, far-red and control on the middle stage of vegetative growth. Light quality sources were made by diodes. Light quality treatments were done in growth chamber. The photoperiod was 16 hours. Light quality treatments were done for 4 hours as daylight extension after 12 hours lighting by fluorescent lamps. Far-red lighting treatment was very effective to prohibit the formation of anthocyanin in the leaves. Blue lighting treatment was increased the anthocyanin accumulation but blue lighting treatment with far-red showed preventing the formation of anthocyanin. In these results, far-red lighting was very effective for preventing the action of cryptochrome by blue lighting on the anthocyanin formation in the leaves of Hanabusaya asiatica.

Free access

There are 25 species of aster in Korea. There is a controversy about the taxonomical classification of Aster. The genus Aster was classified into four genera, Aster, Gymnaster, Kalimeris, and Heteropappus, by morphological characters. In order to clarify the phylogenetic position of aster, the nucleotide sequence of the nuclear ribosomal DNA internal transcribed spacer (ITS) region was compared among 11 taxa in Korean native aster. The size of ITS1 and ITS2 ranged from 283 to 286 bp and from 251 to 257 bp, respectively. The size of 5.8S region was 164 bp in 11 taxa. The total length of ITS1, 5.8S and ITS2, A. tripolium was shown to be the shortest length, 701 bp; and A. scaber was shown to be the longest length, 706 bp. The G+C content of ITS1 ranged from 47.9% to 51.2% and ITS2 ranged from 52.2% to 55.1%. The range of each taxon was narrow. The total length of the character matrix was 708 characters. Among them, total indel showed 9; in the ITS1 region indel showed 6 it was 67%; and in the ITS2 region, indel showed 3. Most of the indels showed deletion or insertion of only one base pair, but in A. spathulifolius deleted two base pairs and in A. tripolium deleted five base pairs. But in A. yomena, A. hayatae, A. koraiensis, and A. hispidus, the indel was not detected. Phylogenetic trees did not even make a difference inter-genus, but A. yomena and A. koraiensis called genus Kalimeris and genus Gymnaster, respectively; these constituted a clade. A. hispidus called genus Heteropappus was placed as a sister group to the clade of A. ageratoides and A. glehni.

Free access

This study was conducted to overcome the problems occurring in soil cultured Sandersonia, such as secondary tuber formation, tuber russeting, browning and surface cracking. For the tuber production, soilless culture medium compositions (peatmoss, perlite, cocopeat) and harvesting times [4, 6, 8, 10, and 12 weeks after flowering time (WAF)] were compared. The mother tubers were planted and grown in a plastic box (40 × 60 × 23 cm) under a PE film house with shading in summer season. The tuber number and weight were higher in peatmoss-based media of peatmoss, 1 peatmoss: 1 perlite, and 2 peatmoss: 1 perlite (by volume) than in the other media. Particularly, the plant height and the numbers of leaf and flower were also higher. The contents of total nitrogen and phosphorus in leaves were lower when the tubers were grown in perlite. Leaf area index per plant reached the maximum at 8 WAF and decreased thereafter. The optimal harvesting time for tuber production was 8-10 WAF.

Free access

This experiment was carried out to determine correct applications of GA3 for the production of cut flowers of Zantedeschia albomaculata cv. Black Magic in highlands. Tubers were treated with GA3 in concentrations of 0, 100, and 200 mg·L-1. ABA contents in the tubers and roots were twice as high (20∼25 pmol/mL) in the control as in GA3-treated tubers and roots. ABA content in roots increased with increasing GA3 concentration. Growth of the calla was investigated according to the tuber hardness (3.3, 6.0 kg·cm-2), GA3 concentrations (0, 100, 200 mg·L-1), and GA3 treatment duration (24 h, 12 h, and 30 min before planting). Tubers with higher tuber hardness were strong against soft rot, regardless of the GA3 concentrations and treatment durations. Tubers with lower tuber hardness showed over 90% soft rot occurrence when treated with 200 mg·L-1 GA3 for 24 h before planting. However, soft rot did not occur when treatment with 200 mg·L-1 GA3 was used for 12 h before planting.

Free access

The efficiency of volatile formaldehyde removal was assessed in 86 species of plants representing five general classes (ferns, woody foliage plants, herbaceous foliage plants, Korean native plants, and herbs). Phytoremediation potential was assessed by exposing the plants to gaseous formaldehyde (2.0 μL·L−1) in airtight chambers (1.0 m3) constructed of inert materials and measuring the rate of removal. Osmunda japonica, Selaginella tamariscina, Davallia mariesii, Polypodium formosanum, Psidium guajava, Lavandula spp., Pteris dispar, Pteris multifida, and Pelargonium spp. were the most effective species tested, removing more than 1.87 μg·m−3·cm−2 over 5 h. Ferns had the highest formaldehyde removal efficiency of the classes of plants tested with O. japonica the most effective of the 86 species (i.e., 6.64 μg·m−3·cm−2 leaf area over 5 h). The most effective species in individual classes were: ferns—Osmunda japonica, Selaginella tamariscina, and Davallia mariesii; woody foliage plants—Psidium guajava, Rhapis excels, and Zamia pumila; herbaceous foliage plants—Chlorophytum bichetii, Dieffenbachia ‘Marianne’, Tillandsia cyanea, and Anthurium andraeanum; Korean native plants—Nandina domestica; and herbs—Lavandula spp., Pelargonium spp., and Rosmarinus officinalis. The species were separated into three general groups based on their formaldehyde removal efficiency: excellent (greater than 1.2 μg·m−3 formaldehyde per cm2 of leaf area over 5 h), intermediate (1.2 or less to 0.6), and poor (less than 0.6). Species classified as excellent are considered viable phytoremediation candidates for homes and offices where volatile formaldehyde is a concern.

Free access