Hee Jung Ji

Transgenic Expression of MsHsp23 Confers Enhanced Tolerance to Abiotic Stresses in Tall Fescue

Tall fescue (Festuca arundinacea Schreb.) is an important cool season forage plant that is not well suited to extreme heat, salts, or heavy metals. To develop transgenic tall fescue plants with enhanced tolerance to abiotic stress, we introduced an alfalfa Hsp23 gene expression vector construct through Agrobacterium-mediated transformation. Integration and expression of the transgene were confirmed by polymerase chain reaction, northern blot, and western blot analyses. Under normal growth conditions, there was no significant difference in the growth of the transgenic plants and the non-transgenic controls. However, when exposed to various stresses such as salt or arsenic, transgenic plants showed a significantly lower accumulation of hydrogen peroxide and thiobarbituric acid reactive substances than control plants. The reduced accumulation of thiobarbituric acid reactive substances indicates that the transgenic plants possessed a more efficient reactive oxygen species-scavenging system. We speculate that the high levels of MsHsp23 proteins in the transgenic plants protect leaves from oxidative damage through chaperon and antioxidant activities. These results suggest that MsHsp23 confers abiotic stress tolerance in transgenic tall fescue and may be useful in developing stress tolerance in other crops.

Identification of Copper and Cadmium Induced Genes in Alfalfa Leaves through Annealing Control Primer Based Approach

The present research investigated copper and cadmium stress-induced differentially expressed genes (DEGs) using annealing control primers (ACP) with the differential display reverse transcription polymerase chain reaction technique in alfalfa (Medicago sativa L. cv. Vernal) leaves. Alfalfa leaves were subjected to of copper and cadmium treatment for a period of 6 h. A total of 120 ACPs was used. During copper and cadmium treatment, 6 DEGs were found to be up or down regulated. During copper stress treatment, 1 DEG was up-regulated, and 3 novel genes were discovered. Similarly, during cadmium stress treatment, 1 DEG was up-regulated and 5 novel genes were identified. Among all 6 DEGs, DEG-4 was identified as the gene for trans-2,3-enoyl-CoA reductase, DEG-5 was identified as the gene for senescence-associated protein DIN1 and DEG-6 was identified for caffeic acid O-methyltransferase. All the up-regulated genes may play a role in copper and cadmium stress tolerance in alfalfa.

Development and Characterization of Tall fescue Variety 'Greenmaster2ho'

Subtropical Livestock Research Institute, National Institute of Animal Science, RDA, KoreaABSTRACTA new tall fescue variety(Festuca arundinacea Schreb.) named ‘Greenmaster2ho’ was developed by the National Institute of Animal Science, Rural Development Administration, in Cheonan, Korea from 2010 to 2014. For the synthetic seed production of this new variety, 5 superior clones were selected and polycrossed: 09XFa02, 09XFa03, 09XFa11, 09XFa13, and 09XFa14. The agronomic growth characteristics and forage production capability of the seeds were studied at Cheonan from 2010 onward, and regional trials were conducted in Cheonan, Hoengseong, Jeju, and Jinju from 2012 to 2014. Greenmaster2ho showed resistance to disease, persistence, and regrowth ability that were all enhanced when compared with Fawn. At 15,119kg/ha, the dry matter (DM) yield of Greenmaster2ho was 29% higher than that of Fawn, but the nutritive value of both varieties as forage was similar. This study aimed to make a contribution to the vitalization of the Korean grassland industry by developing a new tall fescue variety with excellent environmental adaptability. (Key words :Tall fescue, Endophyte, Greenmaster2ho, Variety, Grassland)

Effect of Seeding Method and Pre-emergence Herbicides on Plant Growth and the Production of Sorghum × Sudangrass Hybrid

Jeong Sung Jung, Ki-Won Lee, Ki Choon Choi, Hee Jung Ji, Hyung Soo Park, Won Ho Kim, Young-Jin Kim,Sang Hak Lee and Sang-Hoon Lee*National Institute of Animal Science, Rural Development Administration, Cheonan 330-801, KoreaABSTRACTThe following experiments were used to evaluate the effect of seeding method and pre-emergence herbicides on weed control and the production of the sorghum×sudangrass[sorghum bicolor (L.) Moench] hybrid under field and in vitro conditions. Under the in vitro condition, we evaluated how different kinds of herbicides affect the rate of seed germination and the growth of early seedlings in the sorghum×sudangrass hybrid treated with herbicides. Simazine, alachlor, and methabenzthiazuron were used, and their concentration levels were 0%, 40%, 70%, and 100%. The germination ratio of the seeds was reduced by the application of simazine, methabenzthiazuron, and alachlor compared with the control(distilled water). The alachlor application severely decreased the sorghum germination ratio. However, seed germination was not greatly influenced by the concentration level of the herbicides. Root and shoot length were increased in the following order: control>simazine>methabenzthiazuron>alachlor. Overall, alachlor significantly reduced root length more than shoot length. The differential tolerance of the sorghum×sudangrass hybrid to pre-emergence herbicides by seeding method was then tested under the field condition. The plants were severely injured by the alachlor application, leading to a great reduction in the number of stems. However, for the simazine and methabenzthiazuron applications the number of stems lost was slightly lower than it was for the alachlor and simazine+alachlor applications. In the seeding method, drilling was more effective in reducing herbicide injury than broadcasting. All of the herbicides effectively controlled weeds. The simazine and methabenzthiazuron applications showed a significantly higher dry matter(DM) yield. However, the alachlor and simazine+alachlor applications severely reduced the DM yield. This result suggests that the alachlor application has a significant effect on plant production. Similarly, the total digestible nutrient(TDN) yield was greatly reduced by the alachlor and simazine+alachlor applications. From the results presented above, we concluded that the yield of DM was the highest for broadcasting with no herbicide. and drilling was the most-effective way to reduce herbicide injury. The simazine application was the most-effective herbicide, showing the highest forage yield and TDN yield.(Key words :Pre-mergence herbicide, Sorghum×sudangrass hybrid, Seeding method, Production, Plant growth)

Effects of Seeding and Organic Fertilizer Rates and Harvest time on Kenaf Yield and Feed Value

This study was conducted in 2014 in the Gangjin area of Jeonnam province for the purpose of confirming the potential of Kenaf as an alternative feed crop of rice. The weather and soil conditions were favorable and there was no adverse effect on the growth of Kenaf. The amount of seeding was given at 10 kg, 15 kg and 20 kg. As the seeding volume increased, plant height and dry matter yield increased, and stem diameter and number of nodes decreased. The highest growth rate was observed between 75 and 90 days from the date of planting(p<0.05). As the growth progressed, stem rate increased and leaf rate decreased(p<0.05). Increased amount of seeding and growth resulted in decreased CP and TDN and increased ADF and NDF, which resulted in the decreased economic value of Kenaf as a feed crop. The result of increasing the use of organic fertilizer to 20 kg and 30 kg was similar to increasing the amount of seeding. As organic fertilizer usage increased, dry matter yield and growth rate improved(p<0.05). (

Salt-induced Differential Gene Expression in Italian Ryegrass (Lolium multiflorum Lam.) Revealed by Annealing Control Primer Based GeneFishing approach

Salt stress is one of the most limiting factors that reduce plant growth, development and yield. However, identification of salt-inducible genes is an initial step for understanding the adaptive response of plants to salt stress. In this study, we used an annealing control primer (ACP) based GeneFishing technique to identify differentially expressed genes (DEGs) in Italian ryegrass seedlings under salt stress. Ten-day-old seedlings were exposed to 100 mM NaCl for 6 h. Using 60 ACPs, a total 8 up-regulated genes were identified and sequenced. We identified several promising genes encoding alpha-glactosidase b, light harvesting chlorophyll a/b binding protein, metallothionein-like protein 3B-like, translation factor SUI, translation initiation factor eIF1, glyceraldehyde-3-phosphate dehydrogenase 2 and elongation factor 1-alpha. These genes were mostly involved in plant development, signaling, ROS detoxification and salt acclimation. However, this study provides new molecular information of several genes to understand the salt stress response. These genes would be useful for the enhancement of salt stress tolerance in plants.

Isolation and Identification of Short Term Drought-Induced Genes in Zea mays L. Leaves

Drought is one of the detrimental factors that impair plant growth and productivity. In this study, we applied annealing control primer (ACP)-based reverse transcriptase PCR (polymerase chain reaction) technique to identify differentially expressed genes (DEGs) in maize leaves in response to drought stress. Two-week-old maize seedlings were exposed to drought (DT) by suspending water supply. DEGs were screened after 3 days of DT-treated samples using the ACP-based technique. Several DEGs encoding 16.9 protein, antimicrobial protein, hypothetical protein NCLIV_068840, thioredoxin M-type were identified in maize leaves under drought stress. These genes have putative functions in plant defense response, growth and development. These identified genes would be useful for predictive markers of plant defense, and growth responses under drought stress in plants.

Effects of Sodium Chloride Treatment on Seed Germination and Seedling Growth of Italian Ryegrass Cultivars

ABSTRACT This study was conducted to evaluate the performance of Italian ryegrass cultivars for salt tolerance under in vitro condition. Italian ryegrass cultivars such as Greenfarm, Florida80, Kowinearly, and Hwasan101 were tested for their tolerance to various sodium chloride levels (0, 50, 150, 250, and 350 mM). The seed germination, growth, and activities of antioxidant enzymes were investigated under salt treatment. Physiological traits such as seed germination percentage, germination period, shoot and root length, and dry weight were suppressed under entire salt stress conditions. The results indicated that the highest germination percentage and shoot and root length were recorded at normal conditions. Increased sodium chloride levels caused a significant reduction in the seed germination and growth rate. Among the four tested cultivars, Italian ryegrass ‘Hwasan101’ could be considered as salt tolerant owing to its higher germination percentage, better seedling growth and antioxidant activities under salinity stress, whereas Greenfarm cultivar was more sensitive. The selection of Italian ryegrass cultivars for greater tolerance to saline environment would allow greater productivity from large saline lands.(

Effects of Salt and Drought Stresses on Seed Germination and Gene Expression Pattern in Tall Fescue

ABSTRACT Salinity and drought stresses are probably the most significant abiotic factor limiting plant’s growth, also negatively affect seed germination and early seedling development. To study on effect of NaCl and PEG stress on seed germination and gene expression pattern of tall fescue, the levels of NaCl and PEG-induced water stresses were determined in first experiment. Different concentration of NaCl (0 to 350 mM) and PEG (0 to 30%) were used for seed treatment. Seed Germination percentage reduced with increasing osmotic potential of growth medium either due to NaCl or PEG. Seeds were not germinate at 350 mM NaCl or 30% PEG treatment. On the basis of the results, Kentucky31(E-) had more resistant than Fawn in both stress conditions. Furthermore, we have used an annealing control primer-based differential display reverse transcription-polymerase chain reaction method to identify salt- and drought stress-induced differentially expressed genes (DEGs) in tall fescue leaves. Using 120 annealing control primers, a total of 4 genes were identified and sequenced. The possible roles of the identified DEGs are discussed in the context of their putative role during salinity and drought stresses.(