• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.202-202
• /
• 2017

Global climate change resulted in unwarranted change in global temperature and caused heat and cold stress, which are consider major threat to agriculture productivity around the world. The use of plant growth-promoting microbes is an eco-friendly strategy to counteract such stresses and confer tolerance to the plants. In current study, previously isolated endophytic fungi Preussia sp. BSL-10 has been found to produce phytohormones such as IAA and GA and as such, endophyte Preussia sp. BSL-10 found to induced tolerance against heat and cold stress. The results showed that under both heat and cold stress the plant growth parameter such as shoot, root length, shoot fresh weight and root fresh weight is higher in Preussia sp. BSL-10 treated plants as compare to free Preussia sp. BSL-10 control plants. In addition, the stress-sensitive endogenous ABA levels were significantly increased in Preussia sp. BSL-10 host plant. The current result suggest that the phytohormone-producing endophyte Preussia sp. BSL-10 can increase plant resistance toheat and cold stress, in turn improving agricultural productivity.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.12
• /
• pp.1744-1749
• /
• 2010

The role of endophytic fungi in plant growth and development is well documented. However, endophytic fungi with growth promotion capacity have never been isolated from weeds previously. In the current study, we isolated 8 fungal endophytes from the roots of Monochoria vaginalis, a serious weed of rice paddy in Korea. These isolates were screened on Waito-C, in order to identify plant growth promoting metabolites. Two fungal isolates (M5.A & M1.5) significantly promoted the plant height and shoot length of Waito-C during preliminary screening experiments. The culture filtrates (CFs) of M5.A and M1.5 also promoted the shoot length of Echinocloa crusgalli. Gibberellins (GAs) analysis of the CFs of M5.A and M1.5 showed that these endophytic fungi secrete higher quantities of GAs as compared with wild-type G. fujikuroi KCCM12329. The CF of M5.A contained bioactive GAs ($GA_3$, 2.8 ng/ml; $GA_4$, 2.6 ng/ml, and $GA_7$, 6.68 ng/ml) in conjunction with physiologically inactive $GA_9$ (1.61 ng/ml) and $GA_{24}$ (0.18 ng/ml). The CF of M1.5 contained physiologically active GAs ($GA_3$, 1.64 ng/ml; $GA_4$, 1.37 ng/ml and $GA_7$, 6.29 ng/ml) in conjunction with physiologically inactive $GA_9$ (3.44 ng/ml), $GA_{12}$ (0.3 ng/ml), and $GA_{24}$ (0.59 ng/ml). M5.A and M1.5 were identified as new strains of Penicillium sp. and Aspergillus sp., respectively, based on their 18S rDNA sequence homology and phylogenetic analysis.

• Korean Journal of Agricultural Science
• /
• v.37 no.2
• /
• pp.171-175
• /
• 2010

This study was carried out to find the effect on growing media and proper time for water supply in rice seedling stages. Plant height of rice seedling for SIPAN-BRL among current several growing medias was higher in Chuchungbyeo than Ilpumbyeo, and that of root length was higher in check among used growing medias. Fresh and dry weight of shoot and root of two rice cultivar. Water time to absorption on each treatment of growing media concentration took similarly in SIPAN-BNH and check were similar. But 500 minutes did in 100ppm and did 370 and 470minute in 300 and 500ppm, respectively. Wilting time of rice seedling was appeared highly at 300ppm of SIPAN-BRL in Chuchungbyeo and 100ppm of SIPAN-BRL in Ilpumbyeo, while it prolonged at 300ppm in Chuchungbyeo and 500ppm in Ilpumbyeo, respectively. Water content at wilting stage was appeared highly at SIPAN-BRL 500ppm in both Chuchungbyo and Ilpumbyeo, while SIPAN-BNL was high in 300ppm of Chuchung-byeo and Ilpumbyeo, respectively. Plant and root length of SIPAN-BNL treated with 300ppm in 10day-rice seedling were highly appeared, while dry weight of shoot was high at 300ppm SIPAN-BNL.

• Korean Journal of Breeding Science
• /
• v.40 no.1
• /
• pp.15-21
• /
• 2008

It was previously pointed out that mutation is the ultimate source of variation. Adequate variation is needed for plant breeding if there is a limitation in natural genetic resources. When the ionizing radiation has been known to cause chromosomal and genomic alternations, it is widely used for inducing mutagenesis. The electron beam as an ionizing radiation is the principal physical mutagens that induces mutation and effectively used in plant breeding. Since dose-response relationships of electron beam in plant species are rarely known, we investigated the seed germination rate and early seedling growth of irradiated seeds of creeping bentgrass (Agrostis palustris Huds., cv Penn-A1) with various electron beam irradiating conditions (1, 1.3, 2 MeV at both 0.03 mA and 0.06 mA with dose of 100 Gy (Gray) and 0.03, 1, 1.3, 2 MeV at 0.03 mA with dose of 200 Gy, respectively) using electron accelerator at Korea Atomic Energy Research Institute. The growth parameters in terms of shoot length, primary root length, and secondary root length showed similar response between 0.06 / 1 (mA / MeV) at 100 Gy and 0.03 / 0.3 (mA / MeV) at 200 Gy. Bentgrass seed germination was mainly affected by the intensity of irradiated dose (Gray). Germination rate was lowered as the irradiated dose increased. On the other hand, early seedling growth was mainly governed not by the dose of radiation but by voltage.

• Korean Journal of Environmental Biology
• /
• v.21 no.4
• /
• pp.400-404
• /
• 2003

This study was to evaluate the effects of gamma irradiation on the germination, nutrient concentrations and growth of spinach and radish. Both the spinach and radish seeds exhibited relatively higher germination rates in response to the low doses of gamma irradiation compared to the non -irradiated control. Leaf DW of the radish did not respond to gamma irradiation but that of the spinach increased significantly in response to a gamma radiation of 4 Gy (P< 0.05). Leaf growth parameters of the spinach including the leaf area and SLA (leaf area/leaf dry weight) also demonstrated increased responses to gamma irradiation. R/S (root dry weight/shoot dry weight), root DW and root length of the spinach exhibited a positive response to gamma irradiation while those of the radish did not. In contrast, SRL (root length/root dry weight) significantly decreased with gamma irradiation at 8 Gy for the spinach, but not for the radish. The tissue nitrogen concentrations of the spinach showed an increased response to gamma irradiation while that of the radish did not. Furthermore, higher concentrations of phosphorus, potassium, calcium and magnesium were found in the irradiated spinach, but not in the irradiated radish. It seems that the non-specific physiological and/or biochemical activities of spinach might be accelerated by gamma irradiation, possibly accounting for the stimulation of nutrient uptake from the root media and early biomass accumulation in the current study.

• Korean Journal of Organic Agriculture
• /
• v.25 no.1
• /
• pp.125-134
• /
• 2017

This study was carried out to examine the effects of soil sulfur mixture on the control apple valsa canker in apple orchard for two years. In organic apple orchard, The recovery percentages of apple valsa canker were compared among control (no treatment), lime sulfur, and soil sulfur in organic orchards. In conventional apple orchards, those of recovery percentages were compared among control, neoasozin, lime sulfur, and soil sulfur. Compared with control, soil sulfur treatments significantly improved the recovery percentages of apple valsa canker infected trees in organic orchard. However, there were no differences between lime sulfur and soil sulfur treatment in organic apple orchard, except BongHyun orchard experiment in 2013. Compared with control fruit qualities, fruit skin red color and fruit firmness were improved in lime sulfur and soil sulfur treatment, respectively. In conventional orchard, apple trees treated with lime sulfur, soil sulfur or neoasozin improved recovery percentages, compared with those of control trees. Soil sulfur treatments recovered 87.5~97.5% of infected 'Fuji'/MM106 apple trees in organic and conventional apple orchards. The trees applied with neoasozin showed significant lower shoot growth than those of soil sulfur treatment in conventional orchard. Soli sulfur treatment improved fruit red color, but did not affected fruit weight, fruit firmness, soluble solids concentrations, and titratable acidity.

• Current Research on Agriculture and Life Sciences
• /
• v.5
• /
• pp.1-11
• /
• 1987

This study was conducted to evaluate the effect of several fungicides and growth regulators on rice seedling growth and damping-off in seedling boxes for machine transplanting. Fungicide treated plots were better seedling growth, shoot regrowth, rooting ability, change of moisture content than those of nontreated plot. Metalaxyl application of Samgangbyeo and SF8002 application of Nagdongdyeo apparently increased plant height, length of the third leaf and fourth leaf. And metaiaxyl application highly increased dry weight. Fungicide treated plots were highly effective in reducing the incidence of damping-off. Benzyladenine application of Samgangbye and $GA_3$ application of Nagdongbyeo apprently increased plant height. But ABA application highly decreased plant height. ABA application and aCE application resulted in highly increased rooting ability. Fungicide and $GA_3$ treated plots, Metalaxyl and growth regulator treated plots resulted in highly increased plant height. I soprothiolane and growth regulator treated plots resulted in decreased plant height. Dachigaren and lAA treated plot apprently increased dry weight and shoot dry weight/plant height. Fungicide and growth regulator treated plots were highly effective in reducing the incidence of damping-off.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.1
• /
• pp.202-207
• /
• 2010

Plant growth promoting fungi (PGPF) are well known for the production of useful secondary metabolites. However, limited information is available on the gibberellin (GA) production capacity of PGPF of endophytic origin. In the current study, 15 fungal endophytes were isolated from the roots of Crown daisy, and then screened on Waito-c rice, in order to identify plant growth promoting fungi. The fungal isolate MH7 significantly increased the shoot length (12.1 cm) of Waito-c in comparison with control treatment (7.9 cm). In a separate experiment, the culture filtrate (CF) of MH7 significantly promoted the growth attributes of Crown daisy. The MH7 CF was analyzed for gibberellins and it contained all physiologically active gibberellins ($GA_1$, 1.37 ng/ml; $GA_3$, 5.88 ng/ml; $GA_4$, 8.62 ng/ml; and $GA_7$, 2.05 ng/ml) in conjunction with physiologically inactive $GA_9$ (0.83 ng/ml), $GA_{12}$ (0.44 ng/ml), $GA_{15}$ (0.74 ng/ml), $GA_{19}$ (1.16 ng/ml), and $GA_{20}$ (0.98 ng/ml). The CF of MH7 produced higher amounts of $GA_3$, $GA_4$, $GA_7$, $GA_9$, and $GA_{12}$ than wild-type Fusarium fujikuroi, which was used as a control for GA production. The fungal isolate MH7 was later identified as a new strain of Penicillium on the basis of its morphological characteristics and phylogenetic analysis of the 188 rDNA sequence.

• Current Research on Agriculture and Life Sciences
• /
• v.15
• /
• pp.101-107
• /
• 1997

Bioenzyme was made up of two predominant strain, which were nomenclated PN-1 and PN-2, respectively. PN-1 possessed spore forming ability, motility, gram positive, catalase activity, but didn't have oxidase activity, urease activity, nitrate reduction and indole forming ability. Taxonomical characteristics of the PN-2 were similar to PN-1 strain, but colony color of PN-2 was yellow-white and nitrate reduction ability was positive. Predominant strains were ascertained by physiologically and morphologically. PN-1 and PN-2 were identified Bacillus lichenifonnis and Bacillus thuringinensis, respectively. Yield of lettuce significantly increased in first and second bioenzyme treatment. Fresh weight, length of shoot, width of leaves significantly increased in N,P,K and N,P,K followed by Bioenzyme application.

• Korean Journal of Soil Science and Fertilizer
• /
• v.30 no.4
• /
• pp.377-383
• /
• 1997

Studies were conducted on the nature of allelopathic effect of the substances in the waste of ginkgo leaves from pharmaceutic factory. In the first step, to find out whether there was any allelophatic effect, young seedlings of radish and rice were grown in the water (crude) extract of ginkgo leaf waste and in different liquid/lquid partitioned fractions of EtOAc at pH 9, EtOAc at pH 3, and BuOH. As second step, attempts were made to isolate and identify the allelophatic substance in different liquid/liquid partitioned fractions using GC/MS and NMR techniques. The water (crude) extract of ginkgo leaf waste retarded the growth of radish seedlings under 10% concentration. In case of rice seedlings, the water extract of ginkgo leaf extract showed adverse effect on the growth when combined with $3.3{\times}10^{-6}M$ gibberellin A3. All of the liquid/liquid fractions of crude extract showed strong retardation of seedling growth of radish and rice at the concentration of 1%. Allelophatic substance was isolated from the crude extract using liquid/liquid partition, column chromatography and HPLC techniques. The analytical results of isolated componet using GC/MS and NMR proved that the allelophatic substance in the ginkgo leaf wastes is catechol; one of phenol compounds. Based on the experiences current study, a practical method for the testing of allelophatic effect of crude extract of some materials was proposed. In this method, rice seeds were allowed to sprout until the length of coleoptile to reach 0.5 mm. Such seedlings were submerged in the solution containing supposedly allelophatic substance and the length of shoot and root was measured 3 days after treatment.