• Journal of Plant Biology
• /
• v.17 no.4
• /
• pp.31-37
• /
• 1974

Seedlings of Nongbaek representing strong cold tolerant variety of rice plant, Jinheung of medium variety and Tongil of weak variety were used respectively for the present study. These seedlings were water cultured in phytotron which maintained at the daytime and night temperature of 30-$25^{\circ}C$, 20-2$0^{\circ}C$, 20-15$^{\circ}C$ and 15-1$0^{\circ}C$. The growth rate of plant height, tillering rate, increase in dry weight and absorption pattern of important mineral nutrients at their early growth stage under each temperature conditions were observed. Generally, it appeared that Nongbaek was more active in the growth of plant height than Jinheung, and Jinheung was more active than Tongil under low temperature condition. The tillering rate of these three varieties was equally rapid while it was decreased in the order of weak cold tolerant variety, such as Tongil, Jinheung and Nongbaek as the temperature declined gradually. The dry weigh tincreasing curve showed almost the same pattern in the varieties at the treatment of each temperature. Under low temperature conditions, Nongbaek showed higher absorption rate of N per dry weight and higher absorption amount of per plant body, Jinheung followed and Tongil was the lowest. The absorption amount of P2O5 increased in the top part compared with the roots as temperature rose and decreased as temperature declined. There seemed to be no difference of absorption among the varieties which have different cold tolerance each other. Under low temperature the absorption rate of K per dry weight was high, as a whole, especially Nongbaek was markedly higher than the other two. The absorption rate of Ca, Mg and Fe was also equally high in all varieties under low temperature and Nongbaek showed a more absorptive tendency in the absorption amount under low temperature.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.142-142
• /
• 2017

Wheat (Triticum asetivum L.) is one of the major grain crops worldwide. The reduced productivity ascribed by adverse environment is increasing the risk of food security. Wheat cultivars have been actively released by public side since 1960s in Korea. Each variety has been developed for superior regional adaptation, pest resistance and mostly high yield. Heat stress tolerance is one of the major parameters that threaten wheat production in Korea. Heat stress during grain filling period has been conceived as critical level and directly influences on wheat production. We evaluated 11 common wheat cultivars ("Baegjoong", "Dajung", "Goso", "Hanbaek", "Jokyoung", "Joeun", "Jopum", "Keumgang", "Olgeuru", "Sinmichal", "Uri") that were exposed to abnormally high temperature during the grain filling period. Each plant was grown well in a pot containing "Sunshine #4" soil in controlled phytotron facility set on $20^{\circ}C$ and 16 h photoperiod. At 9 day-after-anthesis (DAA9), plants were subjected to a gradual increase in temperature from $20^{\circ}C$ to $33^{\circ}C$ and maintained constantly at $33^{\circ}C$ for 5 days. After the treatment, plants were subjected to gradual decrease to normal temperature ($20^{\circ}C$) and continue to grow till harvest. Seeds were harvested from each tiller/plant. Total chlorophyll contents decrease level as well as grain parameters were measured to evaluate varietal tolerance to heat stress. We also divide each spike into five regions and evaluate grain characteristics among the regions in each spike. The obtained results allow us to classify cultivars for heat stress tolerance. The pedigree information showed that typical wheat lines provide either tolerance or susceptible trait to their off-springs, which enable breeders to develop heat stress tolerance wheat by appropriate parental choice.

• Journal of Photoscience
• /
• v.1 no.2
• /
• pp.135-141
• /
• 1994

Elevated near-UV radiation, containing a large amount of UV-B and a small amount of UV-C, inhibited the development of leaves and tillers, the increase in biomass production, the elongation of plant height, the photosynthetic rate and the chlorophyll content in rice plants in a phytotron. Elevated UV-B radiation filtered through cellulose diacetate film or UV-31 cut filter (transmission down to 290 nm) similarly suppressed each growth component above. Near-UV radiation-caused injuries were alleviated either by elevated CO$_2$ atmosphere or by exposure to high irradiance-visible radiation. On the basis of these findings, we examined cultivar differences in the resistance to UV radiation-caused injuries among 198 rice cultivars belonging to 5 Asian rice ecotypes ( aus, aman, boro, bulu and tjeleh) from the Bengal region and Indonesia and to Japanese lowland and upland rice groups. It was shown that .various cultivars having different sensitivities to the effects of near-UV radiation were involved in the same ecotype and the same group, and that the Japanese lowland rice group and the boro ecotype were more resistant. Among Japanese lowland rice cultivars, Sasanishiki (one of the leading varieties in Japan) exhibited more resistance to near-UV radiation, while Norin 1 showed less resistance, although these two cultivars are closely related. It was thus indicated that the resistance to the inhibitory effects of near-UV radiation of rice cultivars is not simply due to the difference in the geographical situation where rice cultivars are cultivated. From the genetic analysis of resistance to the inhibitory effects of UV radiation on growth of rice using F$_2$ plants generated by reciprocally crossing Sasanishiki and Norin 1 and F$_3$ lines generated by self-fertilizing F$_2$ plants, it was evident that the resistance to the inhibitory effects of elevated near-UV radiation in these rice plants was controlled by recessive polygenes.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.1
• /
• pp.40-47
• /
• 1989

To elucidate the relationship of the Quality of aromatic tobacco to their chemical constituents, certain chemical components and leaf Quality by price were compared among leaves produced, 1) under 4 different light intensities during maturing stage in field, 2) under 4 different temperature of 20$^{\circ}C$. 25$^{\circ}C$. 30$^{\circ}C$ and control of l8-22-28$^{\circ}C$ in phytotron. As the light intensity decreased chlorophyll content of harvested leaves increased, but specific leaf weight and Quality of cured leaves lowered. The content of sugar. pet. ether exts. and volatile organic acids decreased, but total nitrogen, nicotine, ash and pH increased as the .light intensity decreased. As the growth temperature increased days to flower was shortened and the growth was decreased without significant difference in leaf Quality. With higher growth temperature the content of nitrogen, ash and pH increased, but sugar decreased with no difference in pet. ether exts., volatile organic acids and volatile neutral content. Several Quality indices were disscussed for the Quality evaluation of aromatic leaves for two groups, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.6 no.2
• /
• pp.73-76
• /
• 1987

The effects of light, active oxygen, inorganic $SO_3\;^{-2}\;ion$, $SO_2$ fumigation duration, $SO_2$ concentration on the degradation of photosynthetic pigments in Green perilla (Perilla frutescens Suwon No. 8) fumigated by $SO_2$ were investigated inside a phytotron. The results were as follows: 1. With the increase of the $SO_2$ dosage, visible injury and the degradation of chlorophyll increased. 2. The degradation of chlorophyll b was less than that of chlorophyll a and the carotinoid was more easily degratated than chlorophyll b. 3. The degradation of chlorophyll by $SO_2$ fumigation was induced directly by $SO_2$, itself. 4. Light is necessary to the degradation of chlorophyll. $SO_2$ and $O_2^-$ made in the photolysis process of the water molecule were the major components in the degradation of chlorophyll.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.2
• /
• pp.80-84
• /
• 2002

In spite of simple and cheap cultivation method, water broadcast-seeded rice demonstrates uneven and unstable seedling establishment per unit land area and requires more herbicide and labor-input for weed control. Three experiments were conducted in a phytotron at 18$^{\circ}C$ to evaluate the adaptability of seed-mat mulching cultivation technologies in water seeded rice for the uniform seedling establishment and the inhibition of weed occurrence without herbicide application. Five different kinds of mat with different mesh sizes and fabric properties were tested. The emergence of rice was the highest in Lawn-mat treatment, being comparable with the control, in which seeds were sown without mat. The Lawn-mat also exhibited the lowest mat tension. Mat tension may influence the emergence of rice. And once it was soaked in water, it didn't maintain its original shape any more. The emergence rate of rice was the lowest in Safer-mat treatment. In Lawn-mat treatment, which was the most effective for rice emergence in the first study, the differences of emergence and seedling establishment of rice depending on the seeding position (upper, beneath, and between mats) treatments were negligible, while they were higher in dry seeds than in pre-germinated seeds treatment. The emergence as affected by the kinds of mat also showed the same trend when tested using barnyard grass. Depending on the kinds of mat, the inhibition effect of weeds was the greatest in Safer-mat and the poorest in Lawn-mat. These results strongly suggest the possibility that the uniform seedling establishment and weed management without chemical could be achieved simultaneously by seed-mat mulching through the combination of effective mat for the emergence of rice and another efficient mat for the inhibition of weed occurrence. This possibility was also tested in the field.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.1
• /
• pp.41-47
• /
• 2006

To understand the heading habit of recently developed 20 Korean rice cultivars, rice plants in a phytotron were exposed to different temperature: $22.5^{\circ}C(day\;27^{\circ}C/night\;18^{\circ}C),\;27.5^{\circ}C(day\;32^{\circ}C/night\;23^{\circ}C)$, and day-length conditions: 10, 12, 13, 14, 15 hours. Four rice cultivars (Sobibyeo, Juanbyeo, Ilpumbyeo and Shindongjinbyeo) showed relatively short Basic Vegetative Phase (BVP) of 17 to 18 days, while Dasanbyeo showed the longest (35 days) BVP, compared to other remaining 15 tested cultivars which exhibited 24 to 31 days of BVP. In this experiment, it was tried out to separate the eliminable vegetative phase into photosensitivity and thermo-sensitivity with two different pathways. Many tested cultivars, however, exhibited quite different responses under low temperature and / or long day-length conditions. Especially, Surabyeo and Juanbyeo were the most difficult cultivars to separate into photo- or thermo-sensitivity in that the eliminable vegetative phase of these two cultivars increased greatly only under low temperature $(22.5^{\circ}C)$ and long day-length (15 hr.) conditions. Regarding the heading response to temperatures, tested cultivars could be categorized into 2 groups. In 1st group of rice cultivars, the eliminable vegetative phase decreased almost equally as the temperature changed from $20.0^{\circ}C\rightarrow22.5^{\circ}C\rightarrow25.0^{\circ}C\rightarrow27.5^{\circ}C$. In contrast, the 2nd group of rice cultivars exhibited eliminable vegetative phase slowly decreasing when the temperature changed from $22.5^{\circ}C\rightarrow25.0^{\circ}C\rightarrow27.5^{\circ}C$, but rapidly decreasing when the mean temperature changed from $20.0^{\circ}C\;to\;22.5^{\circ}C$. All the cultivars belonged to 2nd group, the heading date would be very delayed if cool summer comes.

• Journal of Radiation Industry
• /
• v.5 no.4
• /
• pp.347-352
• /
• 2011

In order to identify the genetic relationship analysis by acute and chronic gamma irradiation, Arabidopsis (Arabidopsis thaliana L.) were irradiated with 200 Gy of gamma-rays using gamma-irradiator (3,000 Ci; Nordion, Canada) and gamma-phytotron (400 Ci; Nordion, Canada) for acute and chronic irradiation, respectively. Genetic relationship among two acute gamma-irradiated plants (A1 and A24) and three chronic gamma-irradiated plants (C1W, C2W, C3W) were analyzed using the amplified fragment length polymorphism (AFLP) technique compared with each non-irradiated plant. A total of 28 EcoRI and MseI primer combinations were used to screen 8 treatments by the ABI3130 capillary electrophoresis system. Amplified products by 28 primer sets showed 1,679 bands with an average of 51 bands per primer combination. Out of the total bands scored, 1,164 fragments were polymorphic bands, with different alleles existing among the treatments. The cluster analysis was performed using the UPGMA (Unweighted Pair Group Method using Arithmetic) in the computer program NTSYS-pc. In clustery analysis, acute gamma-irradiation showed higher genetic variation compared with chronic gamma-irradiation.

• Journal of Soil and Groundwater Environment
• /
• v.19 no.6
• /
• pp.37-48
• /
• 2014

Lab scale rhizofiltration by using four plants was performed to investigate the uranium removal efficiency from groundwater. Lettuce (Lactuca sativa L.), Chinese cabbage (Brassica campestris L.), radish sprouts (Raphanus sativus L.) and buttercup (Oenanthe javanica) were cultivated during 3 weeks in the phytotron. Glass jar ($12cm{\times}12cm{\times}8cm$ for each), containing 350 ml of the artificially uranium contaminated solution was used for 72 hours of the rhizofiltration. In experiments with different initial uranium concentration ($18.00{\mu}g/L$, $31.00{\mu}g/L$, $84.00{\mu}g/L$ and $116.00{\mu}g/L$) in solution, more than 70% of the initial uranium were removed by using lettuce, Chinese cabbage and radish sprouts and the residual uranium concentration in solution maintained lower than USEPA water tolerance limit ($30{\mu}g/L$). From the rhizofiltration experiments at various pH conditions, the highest uranium removal for all four plants was acquired at pH 3 in solution. Rhizofiltration experiments testing two field samples of groundwaters having high uranium concentrations ($86.00{\mu}g/L$ and $173.00{\mu}g/L$) were duplicated and more than 83% of the initial uranium were removed from the groundwater within 72 hours of rhizofiltration by using radish sprouts, which, suggests that the rhizofiltration can be a useful process to remediate uranium contaminated groundwater in the field. After the rhizofiltration experiment, the SEM and EDS analyses for the root surface of the radish sprouts were conducted, suggesting that the main mechanism of the rhizofiltration for the removal of uranium from groundwater would be surface precipitation on the root surface of the plant.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.4
• /
• pp.330-335
• /
• 1993

Sesame cultivars were treated with temperature and daylength to determine the environmental variance of Antioxidant content The experiment was performed in phytotron with 11, 13, 15hours of daylength and 20/15, 25 120, 30/25$^{\circ}C (day / night) of temperature treatment. Varietal differences of antioxidant content were significant by the temperature and daylength treatment. Antioxidant content was incrased at higher temperature(25/2$0^{\circ}C$, 30/25$^{\circ}C) and daylength(13hours) but decreased at lower temperature (20/15$^{\circ}C), short daylength (l1hours) and long day length (15hours) condition. Sesamin content were showed 0.06% difference as maxium by the temperature treatment, while 0.03% by the daylength treatment. Sesamolin content were showed 0.03% difference as maxium by the temperature treatment, while 0.01% by the daylength treatment. The antioxidant content was influenced by the increased temperature than daylength.