• Korean Journal of Plant Tissue Culture
• /
• v.28 no.2
• /
• pp.81-85
• /
• 2001

The experiment was conducted to know the effect of plant growth regulators on axillary bud elongation from in vitro stem cutting and the possibility of virus-free stock production. Axillary buds were well elongated in 3/4 strength MS medium supplemented with 0.1 or 0.5 mg/1 BA and 0.05 mg/1 NAA. Transferred plantlets could be established well in vermiculite and peat moss mixture (3:1, v/v) compare to other mixtures. In virus indexing, all the varieties of mother plants were infected by GLRV Ⅲ. Infected percentages of the three varieties were ranged from 30% to 75%. But negative response was revealed against the other species of virus, GLRV Ⅰ, GFLV and ArMV. Plantlet of 'Schuyler' and 'Muscat of Alexandria', which were cultured in vitro, showed positive response against GLRV Ⅲ and infected percentage of the former was 37.5% but the latter, 12.5%. On the other hand, that of 'Campbell Early' negativiely responded against all the species of virus indexed.

• Plant Biotechnology Reports
• /
• v.3 no.3
• /
• pp.243-250
• /
• 2009

In the present study, a simple one medium formulation protocol for callus culture, somatic embryogenesis and in vitro production of ${\beta}-carboline$ alkaloids and diosgenin in Tribulus terrestris L. was developed. Extensive callus induction and proliferation was obtained in leaf explant on Murashige and Skoog (MS) medium supplemented with $5.0{\mu}M$ 6 benzyl adenine (BA) and $2.5{\mu}M$ ${\alpha}-naphthaleneacetic$ acid (NAA). The embryogenic callus was maintained on subculture to fresh parental medium at 4-week intervals over a period of 28 months. The frequency of embryo formation was at a maximum ($18.1{\pm}0.9$ per g of callus) on MS medium containing $5.0{\mu}M$ BA and $2.5{\mu}M$ NAA together with $75mg\;1^{-1}$ casein hydrolysate. Globular embryo developed into torpedo stage embryo under the influence of starvation. The accumulation of ${\beta}-carboline$ alkaloids (harmaline and harmine) and steroidal saponin (diosgenin) in non-embryogenic and embryogenic callus culture derived from leaf explant was compared with root, leaf, stem, and fruit of the mother plant. The embryogenic callus accumulated equivalent amounts of harmaline ($66.4{\pm}0.5{\mu}g/g$ dry weight), harmine ($82.7{\pm}0.6{\mu}g/g$ dry weight), and diosgenin ($170.7{\pm}1.0{\mu}g/g$ dry weight) to that of the fruit of T. terrestris. The embryogenic callus culture of this species might offer a potential source for production of important pharmaceuticals.

• Korean journal of applied entomology
• /
• v.47 no.1
• /
• pp.101-105
• /
• 2008

Effects of different application of nematicides (fosthiazate 5% G, ethoprophos 5% G, and diazinon 34% EC) for the control of Aphelenchoides fragariae in strawberry were evaluated in a greenhouse experiments. Mother strawberry (Fragaria grandiflora) cv. Yeohong were dipped in solution of nematicides (fosthiazate or ethoprophos at 2.5 g a.i./liter in $20^{\circ}C\;or\;46^{\circ}C$) for 10 min. and planted in a greenhouse for dipping treatment. For the compare, mother strawberry were dipped in hot water for 10 min. without chemicals. For soil treatment, fosthiazate or ethoprophos at 3 kg a.i./ha were mixed into soil. For foliar spray, diazinon at 3.4 g a.i./liter was sprayed at foliage until runoff. At 40, 80, and 100 days after planting, runners were harvested from each treatment and the rate of nematode infestation and the number of nematodes per plant were examined. After 100 days of planting, mother strawberry plants dipped in fosthiazate solution (2.5 g a.i./liter, $20^{\circ}C$) for 10 min. produced more number of healthy runners and reduced % of infected runner as much as 90% and also had fewer nematodes per runner. Fosthiazate was more effective than ethoprophos. Foliar application of diazinon was reduced A. fragariae populations only in early season. Hot water treatment and nematicide soil treatment were less effective.

• Horticultural Science & Technology
• /
• v.29 no.2
• /
• pp.95-101
• /
• 2011

The influence of physicochemical properties of root substrates on the growth of mother plants and occurrence of daughter plants in 'Seolhyang' strawberry propagation were investigated through plastic bag cultivation. Six different formulations of root substrates were coir dust + perlite (5:5, A), coir dust + perlite (6:4, B), coir dust + perlite (7:3, C), coir dust + coconut chip (7:3, D), coir dust + coconut chip (6:4, E), and peatmoss + vermiculite (5:5, v/v; F). The total porosities (TP) and container capacities (CC) of all root substrates were higher than 85% and 55%, respectively, indicating that all substrates were in the acceptable range. But the TP and CC of F substrate were 91.5% and 60%, respectively, which were the highest among the root substrates tested. In the soil chemical properties analyzed before planting and after harvesting of 'Seolhyang' strawberry mother plants, the root substrates of A, B, C, and F had higher electrical conductivity and $NO_3$-N concentrations than those of D and F. The root substrates of A, B, C, and F had heavier runner fresh and dry weights, longer runner lengths, and more daughter plant occurrence than those of D and F. The treatment F had higher tissue N content than any other treatments at 120 days after the transplanting of 'Seolhyang' strawberry and statistical differences were not observed among remained 5 substrates. The treatment of F also had the higher tissue contents of other nutrients except N analyzed at 120 days after transplanting. These results indicated that soil chemical properties rather than physical properties severely influenced the growth of runners and occurrence of daughter plants.

• Journal of Bio-Environment Control
• /
• v.21 no.4
• /
• pp.385-391
• /
• 2012

This study was conducted to investigate the effects of the runner cutting time on the growth and yield of strawberry (Fragaria ${\times}$ ananassa cv. Maehyang and Seolhyang) during nursery period of two consecutive years (2009 and 2010). Strawberry runners which connected from mother plants to daughter plants were cut 30, 20, 10 and 5 days before transplanting day (11 Sep. 2009 and 10 Sep. 2010). When runner cutting time delayed, more nutrition was supplied to the daughter plant until late nursery period. It showed that there was a tendency to increase the fresh weight, crown diameter and leaf chlorophyll content. On the other hand, when the runner was cut earlier, the growth of underground part such as root weight was improved. Irrigation demand increased to 29.7% in case of runner cutting from mother plant compared with runner non-cutting treatment. In addition, infection ratio of anthracnose through runner part was 37.6% higher in case of runner cutting than that of runner non-cutting treatment. After transplanting, budding and flowering period were delayed up to 2 or 3 days because of late runner cutting. But there was no significant difference in marketable fruit yield among runner cutting times. It is recommended to conduct runner cutting 5 or 10 days before transplanting for reducing the occurrence of anthracnose.

• Research in Plant Disease
• /
• v.15 no.3
• /
• pp.202-208
• /
• 2009

The genetically modified leaffolder-resistant (Cry1Ac1) rice plant was evaluated for the changes of resistance by comparing the occurrence of major diseases with a japonica type Korean rice variety, Nakdong which was the mother plant of the transgenic rice event, in greenhouse and field conditions. There was no difference in the occurrence of sheath blight and Helminthosporium blight between the two varieties in the fields. We couldn't find any difference of resistance for fungal blast and bacterial leaf blight by artificial inoculation in greenhouse. There was also no difference in the susceptibility to sheath blight in artificial inoculation tests confirming the results in the fields. The possibility of gene transfer of Bar and Cry1Ac1 from the genetically modified rice plant to naturally infected pathogens such as Fusarium moniliforme and Pyricularia oryzae in the field conditions was tested by PCR. And the possible transfer of those genes by continuous inoculation of Xanthomonas oryzae pv. oryzae and Rhizoctonia solani was also tested. However, we couldn't find any possibility of transfer of the genes in natural and artificial conditions.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.18 no.4
• /
• pp.253-263
• /
• 2016

Chrysanthemum production would benefit from crop growth simulations, which would support decision-making in crop management. Chrysanthemum is a typical short day plant of which floral initiation and development is sensitive to photoperiod. We developed a model to predict phenological development and leaf appearance of chrysanthemum (cv. Baekseon) using daylength (including civil twilight period), air temperature, and management options like light interruption and ethylene treatment as predictor variables. Chrysanthemum development stage (DVS) was divided into juvenile (DVS=1.0), juvenile to budding (DVS=1.33), and budding to flowering (DVS=2.0) phases for which different strategies and variables were used to predict the development toward the end of each phenophase. The juvenile phase was assumed to be completed at a certain leaf number which was estimated as 15.5 and increased by ethylene application to the mother plant before cutting and the transplanted plant after cutting. After juvenile phase, development rate (DVR) before budding and flowering were calculated from temperature and day length response functions, and budding and flowering were completed when the integrated DVR reached 1.33 and 2.0, respectively. In addition the model assumed that leaf appearance terminates just before budding. This model predicted budding date, flowering date, and leaf appearance with acceptable accuracy and precision not only for the calibration data set but also for the validation data set which are independent of the calibration data set.

• Korean Journal of Plant Resources
• /
• v.35 no.4
• /
• pp.502-507
• /
• 2022

In the present study, plant regeneration through adventitious shoot formation from hypocotyl segments of in vitro seedlings of groundcherry (Physalis angulata L.) was investigated to determine the optimum culture conditions for highly efficient regeneration of the species. Adventitious shoots in hypocotyl segments were efficiently induced on MS media with low concentrations of BAP, specifically, with 0.5-1.0 mg/L BAP singly or in combination with 0.1-0.5 mg/L NAA. The 1.0 mg/L BAP single treatment was most effective for forming multiple adventitious shoots. When the induced shoots were transferred to the root induction media, low concentrations of NAA, IBA, and IAA enhanced the development of adventitious roots from adventitious shoots, suggesting that low concentrations of auxins were optimal for producing regenerated plantlets. The number of roots per shoot was large (> 2.0), and the root length exceeded 8.0 cm. In particular, the development and the overall shape of the roots were ideal. Furthermore, the number and length of shoots exceeded 2 and 6.0 cm, respectively. When the regenerated plantlets were transferred to compost soil, the root and shoot systems had developed well to the point that all of the regenerated plantlets acclimated successfully, resulting in normal morphology and growth characteristics, similar to those of the mother plant. Therefore, plant regeneration via adventitious shoot formation is expected to be one of the main methods for producing groundcherry on a large scale for a stable supply of the raw materials.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.57 no.3
• /
• pp.209-214
• /
• 2012

Indigo crop, Persicaria tinctoria H. Gross is an annual plant containing natural colorant, the blue dye indigo, and local cultivars had been cultivated to produce natural indigo for textile dyeing in Korea since ancient times. Naju No. 2 is a new mass-selected line from the mother population, Naju Local cultivar. In this study, two breeding lines of Naju Local and Naju No. 2, have been cultivated in four different locations, the South regions of Korea, to compare plant growth and yield characteristics between two lines. Naju No. 2 was higher in plant height, and Naju Local has more 1st branches. Naju No. 2 has larger leaf area and higher width/length ratio of leaf, showing the round leaf type as morphological stable character without regional differences. Though there was considerable regional variation in fresh and dry top weight of harvested plant, the significant difference of plant weight between two lines were not shown. The ratio of leaf to total shoot of dry weight of Naju No. 2 was higher than one of Naju Local, indicating that Naju No. 2 has better yielding of colorant which is synthesized mostly in leaf. Naju No. 2 contained more Niram (crude indigo extract) and indigo, and showed much blueness at dyeing of silk using fresh leaves than Naju Local. We concluded that a new line, Naju No. 2 could be a superior cultivar due to having higher leaf yield and better quality of natural colorant than Naju local cultivar.

• Journal of Plant Biology
• /
• v.30 no.1
• /
• pp.43-57
• /
• 1987

The epidermal structure and stomatal types in vegetative and reproductive organs of three species of Bryophyllum(B. crenatum, B. diagremontion, B. tubiflorum) were described. The epidermal cells were polygonal, isodiametric, and rectangular in the leaves and stems, and elongated cells in the stamens, styles, and ovaries. These cells were commonly thick, and arched or sinuous in the leaves, epiphylous bunds, petals and ovaries. They were straight in the stems, petioles, pedicels, and peduncles. In both vegetative and reproductive organs, the subsidiary cell walls were commonly thin and mostly arched in all the organs. The great majority of the mature stomata in all the organs were helicocytic type with a helix of four to six subsidiary cells. The mature stomata varied from organ to organ with regard to the number and arangement of subsidiary cells. The ontogenetic type of stomata in all the organs was mostly helico-eumesogenous type. This type was subdivided into three subtypes such as parahelico-eumesogenous, anomohelico-eumesogenous, and diahelico-eumesogenous stomata on the basis of the division angle fo the guard mother cell. Sometimes, the anisoeumesogenous type was found in various organs. This type was subdivided into three subtypes such as paraniso-eumesogenous, anomoaniso-eumesogenous, and dianisoeummesogenous stomata. The tetra-eumesogenous and duplotetra-eumesogenous types were rarely found; the former in the leaf of B. crenatum and the latter in the leaf of B. diagremontiana. Anomometric patterns in the mesogenous categorry of stomatal types was observed in a few organs of all the materials. A new stomatal type with tetra-eumesogenous stoma within a girdle of three subsidiary cells fo aniso-eumesogenous in the leaf of B. diagremontiana was firstly observed in the vascular plants. This stoma was termed the cotetra-aniso-eumesogenous type. Anormal stomata such as aborted stomata, single guard cells, stoma with a constricted part in the middle of large guard cells, and arrested stomata were found in the various organs of all the materials.