• ALGAE
• /
• v.25 no.1
• /
• pp.27-35
• /
• 2010

Marked declines in seagrass meadows are increasingly being reported from coasts around Korea and many regions of the world. The transplantation of seagrasses has been attempted to mitigate and control their degradation from a range of anthropogenic factors. In this study, Zostera marina shoots, which were collected from a donor bed in Koje Bay, were transplanted in Jindong Bay in December 2004. In 2008, a comparative investigation of shoot morphology, growth, and reproduction strategy of Z. marina was carried out between the donor and transplant sites to assess their adaptation success. Shoot height, individual shoot weight, and leaf productivity at the transplant site were significantly greater than those at the donor site. However, below-/aboveground tissue ratio was significantly lower at the transplant site compared to the donor site. Z. marina survival was maintained through vegetative reproduction, while peak season for lateral shoot recruitment was late winter for both donor and transplant site populations. However, vegetative reproduction mainly occurred during late winter and spring at the transplant site, whereas lateral shoots were evident across all seasons except late spring in the donor site. More pronounced seasonal variations were found at the transplant site compared to the donor site. These results indicate that Z. marina populations at the two sites possess distinct phenotypic variations induced by different environmental conditions, and Z. marina transplants have adapted well to the new transplant environment.

• Journal of Korean Society of Forest Science
• /
• v.79 no.4
• /
• pp.359-366
• /
• 1990

This study was carried out to investigate rooting rate, plagiotrophic growth and root-promoting effect of IBA in Taxus cuspidata S, et Z. cuttings. The results obtained were summarized as follows ; 1. As the ortet ages of cuttings were increased in 5, 10, to 20 years, the rooting rates were decreased in order of 85.7%, 81.7% and 62.4%, and the number of primary roots were also decreased in 5.3, 3.7 and 2.9, respectively. 2. Rooting rate by cutting types of lateral shoot were higher than those of main shoot type, significant at the 1% level. 3. IBA(l00ppm) treatment promoted the rooting rates and the number of primary roots. 4. As the ortet ages were increased in 5, 10 to 20 years, angles of central shoot of rooted cuttings which mesured cyclophysis were decreased in order of $75.9^{\circ}$, $68.5^{\circ}$ and $59.6^{\circ}$, respectively, significant at the 1% level. 5. Average angles showed $77.0^{\circ}$ for main shoot cutting, $65.9^{\circ}$ for upper lateral shoot and $61.7^{\circ}$ for lower lateral, which was significant at 1% level, and lateral shoot cutting showed more topophysis than main shoot cutting. 6. Shoot length of rooted cuttings from main shoot cutting was longer than that from lateral shoot significant at the 1% level. 7. Relationship between some characteristics showed highly positive correlation.

• Journal of Bio-Environment Control
• /
• v.17 no.1
• /
• pp.14-19
• /
• 2008

The experiment was investigated the effects of lower root zone temperature on shoot and root growth of 'Akihime' strawberries in aeroponics in cold season. Root growth was decreased with decrease of root zone temperature, especially in lateral roots. Elongation of main roots was highest in $18^{\circ}C$ of root zone temperature. Number of lateral roots and length of lateral roots were lowest in $8^{\circ}C$ of root zone temperature. Lower root zone temperature resulted significantly in decrease of fresh weight of root and shoot and leaf area of strawberry. But there were no significant statistical differences in shoot fresh weight and leaf area in $8^{\circ}C$ and $13^{\circ}C$ of root zone temperature. Leaf length, leaf width and number of leaves of strawberry were decreased in lower root zone temperature. The results of this experiment will be utilized in the winter season cultivation for strawberry in hydroponics.

• Journal of Bio-Environment Control
• /
• v.14 no.1
• /
• pp.52-55
• /
• 2005

An experiment was conducted to evaluate the efficacy of continuous lateral shoot pinching and gradual adjustment of drip irrigation lines in improving plant health as well as fruit yield and quality in white-spined cucumber grown in the greenhouse. Grafted white-spined cucumber seedlings were established at a density of 18,000 plants per ha in a greenhouse. Main stems were pinched at 21st node. Each of the lateral shoots was pinched at the 3rd node and 2-3 fruits per lateral shoot were harvested. Drip irrigation lines were gradually adjusted to provide water to the area of maximum root concentration. Plants grown with these combined treatments produced $55\%$ more lateral shoots and 38% more marketable yield, as compared to the control.

• Molecules and Cells
• /
• v.19 no.3
• /
• pp.342-349
• /
• 2005

Cytokinins are adenine derivatives that regulate numerous plant growth and developmental processes, including apical and floral meristem development, stem growth, leaf senescence, apical dominance, and stress tolerance. However, not much is known about how cytokinin biosynthesis and metabolism is regulated. We identified a novel Arabidopsis gene, ALL, encoding an aldolase-like enzyme that regulates cytokinin signaling. An Arabidopsis mutant, all-1D, in which ALL is activated by the nearby insertion of the 35S enhancer, exhibited extreme dwarfism with rolled, dark-green leaves and reduced apical dominance, symptomatic of cytokinin-overproducing mutants. Consistent with this, ARR4 and ARR5, two representative primary cytokinin-responsive genes, were significantly induced in all-1D. Whereas SHOOT MERISTEMLESS (STM) and KNAT1, which regulate meristem development, were also greatly induced, expression of REV and PHV that regulate lateral organ polarity was inhibited. ALL encodes an aldolase-like enzyme that belongs to the HpcH/HpaI aldolase family in prokaryotes and is down-regulated by exogenous cytokinin, possibly through a negative feedback pathway. We propose that ALL is involved in cytokinin biosynthesis or metabolism and acts as a positive regulator of cytokinin signaling during shoot apical meristem development and determination of lateral organ polarity.

• Journal of Plant Biotechnology
• /
• v.5 no.2
• /
• pp.115-119
• /
• 2003

To determine the appropriate concentrations of nutrients and growth regulators for shoot proliferation and root initiation, several rose hybrid tea cultivars were cultured. Cultured shoot tips and lateral buds from different cultivars proliferated multiple shoots on Murashige and Skoog (MS) medium supplemented with 0 to 4 mg/L BA and 0 to 0.05 mg/L NAA. The ability of the explants to proliferate shoots and initiate roots was affected by genotype, the nodal position of explant, the strength of MS basal medium and growth regulators used. The buds nearest the apex exhibited the slowest rate of development. Most cultivars had the highest shoot proliferation when cultured on MS medium with 2 mg/L BA and 0.01 mg/L NAA, but the degree varied by cultivars. Root development was enhanced by lowering the concentration of MS salts.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 2004.11a
• /
• pp.49-52
• /
• 2004

• Korean Journal of Plant Resources
• /
• v.26 no.6
• /
• pp.709-717
• /
• 2013

The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

• Korean Journal of Agricultural Science
• /
• v.29 no.1
• /
• pp.8-14
• /
• 2002

Spray of maleic hydrazide (MH) was confirmed to be highly effective on the inhibition of lateral shoot growth regardless of grape cultivars and application concentration examined in this experiment. The optimal spray times were 30 days aft er full bloom in 'Kyoho' and 35 days in 'Campbell Early'. However, the optimum season of application should be adjusted depending on the vine vigor. The apical buds of lateral shoot was significantly affected at the concentration of $3,900mg{\cdot}L^{-1}$ resulting in the death and/or abscission. Thus the optimal concentration of MH seemed to be $1,950mg{\cdot}L^{-1}$. The inhibition effect by MH application was derive d from the decrease of node number and length. No adverse effect on fruit quality was found by MH application. In contrast, there was a tendency of anthocyanin in crease in 'Campbell Early' grapes. Results indicated that MH could be an effective agent to reduce the labor charge through the inhibition of later shoot growth.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.4
• /
• pp.189-195
• /
• 2001

This study was carried out to investigate the effects of in vitro culture condition and among lines on growth pattern of lateral buds from nodal cuttings of Phalaenopsis flower stalks. The ratio of bud growing into shoot from nodal cuttings of flower stalks were 90.9% and 54.4% on MS and hyponex medium, respectively. The number of buds grown vegetatively were increased remarkably on the MS medium containing 5 mg/L BA. The rate of buds grown vegetatively was higher in basal and middle parts than in upper part of flower stalks. The flower stalk sections cultured at 25~28$^{\circ}C$ showed the highest ratio of vegetative growth. Medium contamination was decreased by pretreatment of etiolation to the flower stalk. However, the pretreatment did not show specific effects on shoot development and reduction of phenolic compound. Average shoot number which was formed from flower stalk segments in 27 of 30 accessions were 3.17, while high number of shoots were obtained from Phal. 3020 and Phal. 3039. The growth pattern of lateral buds in F$_1$hybrids was similar to that of their parents.