• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.440-446
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• 1986

The physiological reaction of two soybean (Glycine max (L.) Merrill) cultivars tolerant and susceptible to rust (Phakopsora pachyrhizi Syd.) was studied at the AVRDC in Taiwan, ROC. The rust epidemic on the susceptible cultivar began earlier and progressed more rapidly than on the tolerant cultivar. The defoliation by rust infection increased rapidly after the latter half of pod filling. The reduction of LA! by rust in the susceptible cultivar occurred earlier than in the tolerant cultivar. The differences in the chlorophyll content between the rust-free and rust-infected plants was 2.04% in the tolerant, and 16.43% in the susceptible cultivar. The shoot dry weight increased at each growth stage in the fungicide protected plots, but decreased in the non-fungicide protected plots after the R6 growth stage onward and the tendency to decrease was more severe in the susceptible than in the tolerant cultivar. The pod and seed dry weight of the suscep-tible cultivar in the fungicide-protected plot increased dramatically from the R6 growth stage, but in the non-fungicide plot, there was almost no increase in pod and seed dry weight from R6 growth stage, due to rust. The number of empty pods and imperfect grains were increased by rust infection, but the protein content was not afftected. There were reductions of oil content, seed length, seed width, seed thickness, pod thickness, number of pods and seeds, 100 seed weight, and yield due to rust infection. The yield losses by rust infection were 22.3%in the tolerant and 68.7% in the susceptible cultivar.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.215-219
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• 1998

This experiment was conducted to investigate effects of NaCl concentration on photosynthetic rate, free proline content and ion content in tobacco. As NaCl concentration was increased growth was retarded. The decrease growth characteristics(shoot/root ratio was 2.0) at 90mM NaCl indicated that this concentration could be a limiting level. As NaCl concentration was increased photosynthetic rate, transpiration rate, and water use efficiency were decreased. Photosynthetic rate was highly decreased at 60mM NaCl. There was no significant difference between transpiration rate and water use efficiency. Leaf water potential was decreased as NaCl concentration was increased, in that twice lower at 30mM than that of control and drop largely at 120mM NaCl. Free proline content was increased as NaCl increased until 120mM NaCl and drop at 150mM NaCl. The $Ca^{2+}$, $Mg^{2+}$, and $K^+$ contents were increased until NaCl concentration was 120mM. The $Na^{2+}$ content was slowly increased as NaCl concentration increased until 120mM NaCl, and largely increased at 150mM NaCl. There was no significant difference between $Cl^-$ and NaCl treatments except 30 mM NaCl in which $Cl^-$ content was higher than that of control. As NaCl concentration was increased $K^+/Na^+$ ratio was decreased. The negative correlation between $K^+$ and $Na^+$, and positive correlation between $K^+/Na^+$ and protein content were found.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.311-317
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• 2006

Using PCR amplification, we cloned a cellulase gene (ce/H) from the Bacillus subtilis AH18 which has plant growth-promoting activity and antagonistic ability against pepper blight caused by Phytophthora capsici. The 1.6 kb PCR fragment contained the full sequence of the cellulase gene and the 1,582 bp gene deduced a 508 amino acid sequence. Similarity search in protein database revealed that the cellulase of B. subtilis AH18 was more than 98% homologous in the amino acid sequence to those of several major Bacillus spp. The ce/H was expressed in E. coli under an IPTG inducible lac promoter on the vector, had apparent molecular weight of about 55 kDa upon CMC-SDS-PAGE analysis. Partially purified cellulase had not only cellulolytic activity toward carboxymethyl-cellulose (CMC) but also insoluble cellulose, such as Avicel and filter paper (Whatman No. 1). In addition, the cellulase could degrade a fungal cell wall of Phytophthora capsici. The optimum pH and temperature of the ce/H coded cellulase were determined to be pH 5.0 and $50^{\circ}C$. The enzyme activity was activated by $AgNO_3$ or $CoCl_2$. However its activity was Inhibited by $HgC1_2$. The enzyme activity was activated by hydroxy urea or sodium azide and inhibited by CDTA or EDTA. The results indicate that the cellulase gene, ce/H is an antifungal mechanism of B. subtilis AH18 against phytophthora blight disease in red-pepper.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.157-174
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• 1984

Four different levels of nitrogen were applied to 3 naked barley cultivars (Hordeum vulgare L.) Yonezawa, Baekdong and Yeongsanbori. Changes in chlorophyll content, green leaf area and light penetration were monitored after heading. Yield and its components were examined upon these changes. Increased level of N-application delayed the days to heading and ripening by 2-3 and 6-7 days, respectively, in Yonezawa. Yonezawa with a short culm was more resistant to lodging than two tall ones (Baekdong, Yeongsanbori) under heavy nitrogen applications. Yield was affected mostly by the number of spikes per unit area and 1, 000 grain weight at all levels of N-applications. The increase in dry weight of Baekdong was more than in that of Yonezawa. A sharp increase in dry weight was observed after 3 weeks of heading. Maximum yield was obtained at $N_2$ in Yonezawa (234kg/10a) and Baekdong (302kg/10a) and at $N_1$ in Yeongsanbori (332kg/10a). It appears essential to attain the sufficient leaf area and the increase in chlorophyll content for maximum yield. However, too much leaf area at the highest N level up to the ripening stage was not beneficial for dry matter production.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.1
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• pp.49-64
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• 1989

The study was carried out to investigate the effect of control leaf number on growth and chemical characteristics, and on yield and quality In (rue-cured tobacco The rest upper leaves of 14, 16, and 18 leaves per plant were removed at button stage, and the plants were harvested :0, 12, and 16 leaves with discard 4 leaves of the bottom, respectively. 1. There were showed a tendency to increase in length (LL), width (LW), area (LA), fresh (LFW) and dry weight (LDW) per leaf as leaf numbers were decreased, while those per plant and the ratios of increase of those per plant were decreased. 2. In compensation effect (CE), there were increase in LL, LFW, LDW, LL/LW and LDW/LFW with each decreased in leaf numbers while LW was decreased, LA unchanged. 3. There were significant Increases in LL, LW, and LA at 5th~8th stalk positions form bottom (SP), while those .at 13th~16th SF were decreased. Also, LDW at 5th~l0th, and LDW/LFW and weight Per unit leaf area at 11th 16th were Increased as leaf numbers decreased. 4. Mean per plant and CE of nicotine were increased, but those of sugar were decreased with each decrease In leaf numbers. In addition, nicotine contents at 5th~14th SP except for 9th~10th were increased, otherwise sugar contents at 7th~14th were decreased. 5. There were showed a tendency to increase in grade per Plant and in tirade at 5th~8th SP, but decrease in CE of grade as leaf numbers were decreased. There wee significant decrease in grade at 11th~14th SP. Also, ratio of 5 grade was decreased, while ratios of 3 and 4 grades were increased. 6. When the 2 leaves at 3rd~4th SP were harvested, price was decrease 2.6% and yield was increased 5.8 %. 7. When the 6 leaves from convention were removed at but ton stage, effects of apparent, compensational, and net per leaf on yield were -3.9%, +2.6%, and -6.5%, respectively, and those on price were +1.1%, -1.6% and +2.7%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.401-411
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• 2015

Drought stress has detrimental effects on the seedling development, vegetative/ reproductive growth, photosynthesis, root proliferation, anthesis, anthesis-silking interval (ASI), pollination and grain yield in maize. Typically, two weeks before silking through pollination are an important time in maize life. Here we reviewed the effects of drought stress on growth, physiological/ molecular researches for drought tolerance, and breeding to genomics in maize. Drought stress during kernel development increases leaf dying and lodging, decreases grain filling period and grain yield. Physiological factors of drought stress/ effects are water content, water deficits, and water potential. Nowdays molecular marker assisted breeding method is becoming increasingly useful in the improvement of new germplasm with drought stress tolerance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.174-182
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• 1993

Performance of 3 indica ${\times}$ japonica(Chilseungbyeo, Samgangbyeo, and Gayabyeo), 7 japonica(Yeongsanbyeo, Yeongdeugbyeo, Hwajinbyeo, Palgongbyeo, Seumjinbyeo, Tamjinbyeo, and Milyang 95), and 2 indica(Tebonnet and Lemont) rice varieties was tested at 1, 3, 5, and 7cm seeding depths in a growth chamber and field. In the growth chamber the number of days from seeding to seedling emergence increased as seeding depth increased, while percent germination and emergence and emergence / germination ratio decreased. However, in the field seedling emergence at 1em seeding depth delayed slightly compared to 3cm probably due to lack of soil moisture. The number of seedlings and maximum tillers at 1, 3, and 5cm seeding depths was similar, but it was higher compared to 7cm seeding depth. Yield and yield components were similar among the seeding depths when all the varieties averaged although 1,000-grain weight was slightly higher at 7cm deeding depth compared to others. At 1cm seeding depth the length of mesocotyl of all varieties was similar and ranged 0.1-0.2cm and that of coleptile ranged 0.8-1.1cm. As seeding depth increased up to 7cm Tebonnet which showed the highest percent emergence emerged by elongation of both mesocotyl and coleoptile, while the other varieties emerged largely by elongation of coleoptile.

• Journal of Life Science
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• v.7 no.1
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• pp.30-38
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• 1997

For screening thermostable $\alpha$-amylase from thermophiles, various samples from extreme environments such as hot spring and sewage near them, and compoat, wereexamined microbial growth in enrichment culture medium at 55$\circ$C on the assumption that enzymes from thermophiles are inevitable thermostable. One strain showing higher $\alpha$-amylase activity was pure cultured and designated as Bacillus sp. TR-25 from the results of morphological, cultural and physiological characteristics. The most important carbon sourses for the enzyme production were soluble starch, dextrin, potato starch and corn starch. Glucose and fructose had a catabolite repression on the enzyme production. The good nitrogen sources for the enzyme production were yeat extract, nutrient broth, tryptone, corn steep liquor and ammonium sulfate. The enzyme production was accelerated by addition of CaCl$_{2}$. $\cdot $ H$_{2}$O. The optimal medium composition for the enzyme production was soluble starch 2.0%, yeast extract 0.55, CaCl$_{2}$ $\cdot $ 2H$_{2}$O 0.015, Tween 80 0.001%, pH8.0, respectively. In jar fermenter culture, this strain shows a rapid growth and required cheaper carbon and nitrogen source. These properties are very useful to fermentation industry. The $\alpha$-amylase of this strain demonstrated a maximum activity at 80$\circ$C, pH 5.0, respectively. And calcium ion did not improve thermostability of the enzyme. At 10$0^{\circ}C$, this enzyme has 235 of relative activity. Transformation was carried out by thermophilic Bacillus sp. TR-25 genomic DNA. As a result, the transformant has increased thermostable $\alpha$-amylase activity.

• Journal of Ginseng Research
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• v.27 no.2
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• pp.86-91
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• 2003

To develop a new ginseng variety with good quality and high yielding, a lot of individual ginseng plant were selected in the farmers'fields in 1968. Among them, a promising line,680-83-4, has been developed through comparative cultivation of several lines selected with pure line separation from local races in KT&C Central Research Institute, preliminary and advanced yield trials were performed fir 8 years.680-83-4 was designated as KG103, which was then registered as a new variety “Gopoong” with the regional yield and adaptation trials for 10 years (1981-1990) on December 27,2000 in Korea. Gopoong has different phenotype of a dark violet stem and dark red fruit and inverted triangle shape of berries cluster as compared with other varieties. Taproot of Gopoong was longer than local race Jakyungjong, and root yield was 4.5% higher than local race Jakyungjong. In red ginseng quality, the rates of Chun-Jeesam grade(Chun and Jee means 1 st and 2nd grade, respectively) were 16.6% and 9.4% for Gopoong and Jakyungjong, respectively. In these results, it was that Gopoong was superior ginseng line with good quality far manufacture of red ginseng.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.1-6
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• 2010

To evaluate agronomic characteristics for the use of biodiesel crop, 328 collections of sunflower (Helianthus annus L.) were obtained from Genebank in Rural Development Adminstration (RDA). The necessary days from seeding to emergence of collections were from 7 to 12 days, and the days to flowering were widely distributed from 55 to 86 days. Stem length ranged from 131 to 345 cm with a mean of 259 cm, and the mean maturing days were 35 days. The number of head flower was 1~23 ea per plant, and the mean size of head flower was 17.6 cm with a range from 14.7 to 21.3 cm (72.8%). The mean seed number per head flower was 1,430 ea, and the weight of seed per plant ranged from 23 to 379 g with a mean of 91.4 g. The mean seed length was 11.7 mm with a range from 9.0 to 21.5 mm, and the mean diameter was 6.4 mm. The mean weight of seed per litter, 1000 grain weight and seed weight per plant were 322.5 g, 63.3 g and 204 g, respectively. Variation of number of head per plant was largest and weight of grain per plant was large in next among growth and grain characteristics. At the results of correlation analysis among characteristics, the seed diameter was getting bigger and the days for flowering dates were prolonged in the higher stem length plant, but the days to maturing and growth duration was shortened.