• Korean Journal of Environment and Ecology
• /
• v.19 no.1
• /
• pp.1-8
• /
• 2005

The removal affect of nitrogen and phosphorus were analyzed using a Acorus calamus var. angustatus. The nutrient concentration, growth stage of plants and the storage time of polluted water were considered. The results of this study were as follows: after an hour the content of nitrogen and phosphorus were considerably reduced in the Acorus calamus var. angustatus, while after two-four hours the rate of reduction was extremely low. This situation was the same in the early growth stage, growing stage and highest growth stage of the plant. The removal rate of nitrogen and phosphorus with the Acorus calamus var. angustatus was higher, when these two minerals remained in high levels of water. The Acorus calamus var. angustatus was more effective to remove nitrogen than that of phosphorus. The plant removed the most nitrogen and phosphorus when in the highest growth stage, but this was not clear in the growth stages. The removal rate was higher, in the case of moving polluted water to other plants after two days, than in the case of four days of growth in the same plants.

• Korean Journal of Plant Resources
• /
• v.37 no.3
• /
• pp.263-269
• /
• 2024

Embryos of early-ripening peaches could not achieve physiological maturation or undergo abortion before harvest. Embryo rescue is an effective strategy to rescue embryos from early-ripening peaches. Thus, the current study was carried out to determine the appropriate developmental stage and optimal medium composition for embryo rescue in early-ripening peach. Development of open-pollinated 'Yumi' fruit was investigated from 20 to 90 days after full bloom (DAFB) to explore period occurring endocarp hardening. After endocarp hardening, embryo development was observed by light microscopes. Shoot and root meristems were observed at 65 DAFB and embryo size rapidly increased at 75 DAFB. Embryos collected at 75, 80, 85, and 90 DAFB were cultured on four media based on Driver and Kuniyuki (DKW) medium. Germination rate of embryos cultured on four media gradually increased from 75 to 90 DAFB and reached 100% at 90 DAFB. Notably, M3 medium (0.5 DKW supplemented with 6-benzylaminopurine (BAP) 1.0 ㎎/L) displayed the highest germination rate at 75 and 80 DAFB stages. Growth and development of shoot and root were pronounced in plantlet cultured at 90 DAFB stage. While delayed shoot growth was evident in plantlets cultured at 75, 80, and 85 DAFB stages, this retardation could be overcome through the application of growth regulators, particularly in M3 and M4 (0.5 DKW supplemented with BAP 1.0 ㎎/L and indole-3-butyric acid 0.5 ㎎/L) media. Remarkably, roots of plantlet grown in M4 medium exhibited limited elongation. In conclusion, germination rate of embryo and growth of embryo cultured plantlet can be enhanced by collecting seeds from early-ripening 'Yumi' at the 90 DAFB stage and conducting embryo culture using the M3 medium.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.44 no.3
• /
• pp.282-287
• /
• 1999

The object of this study was to determine the difference of the time course changes of transpiration, diffusion resistance and photosynthetic rate of rice at several different growth stages subjected to soil moisture stress (SMS) and recovery by irrigation. A japonica rice cultivar 'Dongjinbyeo', was grown under flooded condition in a plastic container filled with silty loam soil. At 5 main growth stages, the container was treated by SMS until initial wilting point (IWP) and then reirrigated. The duration of SMS until IWP were the longest, 13 days for tillering stage, and the shortest, 7 days for panicle initiation and meiosis stage. The transpiration rate rapidly decreased during SMS and the transpiration rate at IWP of the stressed plant showed 10∼20% compared with control, and the transpiration rate of stressed plant at most growth stages also recovered rapidly after irrigation and then reached 100% of control within a week. The shoot photosynthetic rate in all growth stages rapidly decreased by SMS, and the rates at IWP of stressed plants were de-creased nearly to 0%, beside the treatment at tillering stage. The recovery degree of photosynthetic rate by irrigation ranged from 20 to 90%, showed higher at early growth stages of SMS treatment than that of later stages. At all growth stages the leaf diffusion resistance of stressed plants was over 3 times that of the control resulting from a rapid increase at 3 to 5 days after draining for SMS, and showed quick recovery by irrigation within 3 days after drainage. The above physiological parameters changed in close relation with the decrease of the soil matric potential after SMS. These results indicate that at all main growth stages of rice plants the transpiration and photosynthesis reduction by stomatal closure reponded sensitively to the first stage of SMS closely related with decrease of soil water potential, while those recovery pattern and recovered degree by irrigation are little different by growth stage of rice.

• Clinical and Experimental Reproductive Medicine
• /
• v.32 no.3
• /
• pp.269-277
• /
• 2005

Objectives: Previously, we sought to compile a list of genes expressed during early folliculogenesis by using cDNA microarray to investigate follicular gene expression and changes during primordialprimary follicle transition and development of secondary follicles (Yoon et al., 2005). Among those genes, a group of genes related to the cell size growth was characterized during the ovarian development in the present study. Methods: We determined ovarian expression pattern of six genes related to the cell size growth (cyr61, emp1, fhl1, socs2, wig1 and wisp1) and extended into CCN family (${\underline{c}}onnective$ tissue growth factor/${\underline{c}}ysteine$-rich 61/${\underline{n}}ephroblastoma$-overexpressed), ctgf, nov, wisp2, wisp3, including cyr61 and wisp1 genes. Expression of mRNA and protein according to the ovarian developmental stage was evaluated by in situ hybridization, and/or semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), and immunohistochemistry, respectively. Results: Among 6 genes related to the cell size growth, cyr61 and wisp1 mRNA was detected only in oocytes in the postnatal day5 mouse ovaries. cyr61 mRNA expression was limited to the nucleolus of oocytes, while wisp1 was expressed in the cytoplasm and nucleolus of oocytes, except nucleus. cyr61 mRNA expression, however, was found in granulosa cells from secondary follicles. The rest 4 genes in the cell size growth group were detected in oocytes, granulosa and theca cells. Cyr61 and Wisp1 proteins were expressed in the oocyte cytoplasm from primordial follicle stage. Especially, Cyr61 protein was detected in pre-granulosa cells, Wisp1 protein was not. By using RT-PCR, we evaluated and decided that Cyr61 protein is produced by their own mRNA in pre-granulosa cells that was not detected by in situ hybridization. cyr61 and wisp1 genes are happen to be the CCN family members. The other members of CCN family were also studied, but their expression was detected in oocytes, granulose and theca cells. Conclusions: We firstly characterized the ovarian expression of genes related to the cell size growth and CCN family according to the early folliculogenesis. Cyr61 protein expression in the pre-granulosa cells is profound in meaning. Further functional analysis for cyr61 in early folliculogenesis is under investigation.

• Journal of Plant Biology
• /
• v.27 no.4
• /
• pp.241-251
• /
• 1984

The present study investigated the effects of triacontanol (TRIA) on plant growth and peroxisomal enzyme activities in radish seedlings. The optimum concentration of TRIA with respect to radish seedling bioassay was decided to 1.0mg $1^{-1}$. In comparison to untreated controls (including Tween 20 treatment), 1.0mg $1^{-1}$ TRIA treatment caused an increase in seed germination rate and root growth, but no stimulation in hypocotyl growth. Chlorophyll accumulation in cotyledon during carly development stage increased rapidly, and degradation of chlorophyll in later stage due to the cotyledon senesence was noticeably retarded. Increase of soluble protein content in cotyledon at early period of development was observed. Isocitrate lyase and catalase activity was not significantly different in both the treated and the untreated plants. But, glycolate oxidase activity was inhibited by TRIA down to 20% against controls. Also, the increase of the activity of peroxidase, a leaf-senescence marker enzyme, was continuously retarded over control for 8 days of development. Based on above results, TRIA was found to be active in both the growth and the peroxisomal enzyme activities of radish seedlings.

• Applied Biological Chemistry
• /
• v.11
• /
• pp.185-188
• /
• 1969

This experiment was carried out to investigate on the growth, yield behavior of phosphorus at different stage of growth under the different cultivating conditions in rice plants. The results obtained were as follows; 1) The phosphorous contents was increased in the direct-sowing plots of the rooting time and the early stage of tillering, while in the middle and the later stage of growth, the transplanting plots was increased. 2) In the moisture contents, the direct-sowing plots was more increased than the transplanting plot in the rooting time and the early stage of tillering, while in the later stage of growth, the transplanting plots was increased. 3) The plant height and the weight of dry matter were also increased in the direct-sowing plots of the early stage of tillering, on the other hand, after that the transplanting plots was increased. 4) In the yield of grain, the transplanting plots was increased about 15% compared with the direct-sowing plots.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.44 no.3
• /
• pp.236-242
• /
• 1999

To examine the seedling stand and growth as affected by early seeding dates of dry direct seeded rice in the Honam plain area of Korea, Dongjinbyeo was seeded at six seeding dates from early March to late April in rice fields of silty loam soil(Jeonbuk series) at the National Honam Agricultural Experiment Station (NHAES) for two years, 1996 and 1998. Seedling stand decreased slightly. with an early seeding date, but it produced more than the optimum seedling number except for the seeding of 25 March in 1996. Days to emergence was significantly longer, as seeding date was earlier, and days to emergence by early seeding was shortened only by 8 days because the mean air temperature was lower in 1996 than average, while in 1998, the reduction effect was nine to twenty five days because the mean air temperature was higher than average. In early seeding, various weeds occurred at the emergence date of rice and dominant weeds were Alopecurus aequailis, Ludwigia prostata and Rorippa islandica. NH$_4$$^{+}$ -N content in the soil at the 5th leaf stage and maximum tillering stage were lower, as the seeding date was earlier when nitrogen was split applied as basal and top dressed in 1996, while it was not significantly different among seeding dates when nitrogen was intensively applied as a top dressing in 1998. Tiller number at the maximum tillering stage and panicle number/m$^2$ were more, as seeding date was earlier in 1996, while it was not different in 1998. Filled grain rate and 1,000 grain weight was not different among the seeding dates. Milled rice yield was significantly decreased in the seeding before the middle of March, but in the seeding after late March, it was not varied when compared with the normal seeding date in 1996, while in 1998, there was no difference among seeding dates. From the above results, in consideration of seedling stand, weed occurance, rice growth and milled rice yield, the critical optimum early seeding time in the southern plain area may lie in early April. But it was suggested that when soil moisture is proper for seeding practices, seeding amount is increased and nitrogen is applied after plumule emergence of rice, milled rice yield may not be reduced in the seeding of middle or late March, compared with the seeding in April.l.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.2
• /
• pp.146-152
• /
• 1997

Development of shoot and root, leaf water potential and photosynthetic rate affected by water stress in early growing stage of tobacco were surveyed to interpret stress response in terms of plant physiological and agricultural aspects. The growth of shoot and root was highly suppressed by water stress and the difference in dry weight by rewatering was smaller in root than in shoot. The total root length was highly decreased by water stress and the lengths of root for water stress and non-stress were 74m and 84m, respectively, after rewatering. The root growth treated by water stress was increased between 2nd and 3rd day after treatment indicating that temporary water stress at early growing stage might have increased of root zone activity for early growth stage. The leaf water potentials were decreased to -7.63MPa, -9.47MPa, -11.89MPa, -13MPa at the 2nd, 3rd, 4th and 5th day by water stress. The relative water contents were 75%, 62% and 57% at the 3rd, 4th and 5th day after treatment. Photosynthesis was reduced largely by water stress. The photosynthetic rate after treatment at 2nd day and 3rd day was dropped to 18.15$\mu$mol. $CO_2$/$m^2$ㆍsec$^{-1}$ and 9.35$\mu$mol. $CO_2$/$m^2$ㆍsec$^{-1}$. It was never recovered to the normal, even after rewatering. Stomatal conductance had been reduced since 2nd day after treatment and increased after rewatering.

• Molecules and Cells
• /
• v.45 no.9
• /
• pp.660-672
• /
• 2022

The target of rapamycin complex (TORC) plays a key role in plant cell growth and survival by regulating the gene expression and metabolism according to environmental information. TORC activates transcription, mRNA translation, and anabolic processes under favorable conditions, thereby promoting plant growth and development. Tomato fruit ripening is a complex developmental process promoted by ethylene and specific transcription factors. TORC is known to modulate leaf senescence in tomato. In this study, we investigated the function of TORC in tomato fruit ripening using virus-induced gene silencing (VIGS) of the TORC genes, TOR, lethal with SEC13 protein 8 (LST8), and regulatory-associated protein of TOR (RAPTOR). Quantitative reverse transcription-polymerase chain reaction showed that the expression levels of tomato TORC genes were the highest in the orange stage during fruit development in Micro-Tom tomato. VIGS of these TORC genes using stage 2 tomato accelerated fruit ripening with premature orange/red coloring and decreased fruit growth, when control tobacco rattle virus 2 (TRV2)-myc fruits reached the mature green stage. TORC-deficient fruits showed early accumulation of carotenoid lycopene and reduced cellulose deposition in pericarp cell walls. The early ripening fruits had higher levels of transcripts related to fruit ripening transcription factors, ethylene biosynthesis, carotenoid synthesis, and cell wall modification. Finally, the early ripening phenotype in Micro-Tom tomato was reproduced in the commercial cultivar Moneymaker tomato by VIGS of the TORC genes. Collectively, these results demonstrate that TORC plays an important role in tomato fruit ripening by modulating the transcription of various ripening-related genes.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.206-206
• /
• 2022

Sustainable agriculture is a potential strategy to enable agricultural cultivation systems to feed the growing population under climate change. Sustainable agriculture consists of environment-friendly farming methods that allow the production of crops with minimal harm to the ecosystem. Early establishment in rice might be helpful to adopt sustainable agriculture with less inputs, such as water and phosphorus fertilizer. Two QTLs conferring tolerance to abiotic stress and low nutrition condition, DTY4.1 and Pup1, respectively, are effective for good establishment in the early growth stage under low water and phosphorus fertilizer application. We developed 'Sechanmi' and 'MSI 1-DTY' harboring Pup1 and DTY4.1 into MS11, a japonica rice variety adaptable to tropical regions, using Marker-Assisted Backcrossing (MABC). MS 11-PD lines were developed to meet the demand for less water and P fertilizer application throughout the growth stage of rice. In the F5 generation, water-saving or rainfed cultivation was performed in different P (phosphorus) content. Irrigation was applied only when severe drought was observed one month after transplanting. There was no significant difference observed between the parents and MS11-PD lines in low P conditions. However, MS11-PD lines had more tillers in P-supplied conditions compared to that of the parents 40 and 50 days after transplanting. Under the same amount of P, MS11-PD lines might have higher phosphorus uptake capacity than the parents, increasing the number of tillers and showing better early establishment. The better vegetative growth stage is one of the factors that can potentially increase production by way of higher number of panicles. Through this breeding strategy, it is possible to attain sustainable agriculture by applying less P and water to address the need of a growing population.