• Korean journal of applied entomology
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• v.19 no.3 s.44
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• pp.135-140
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• 1980

Out of 12 seed samples of Sesamum indicum L. tested, Macrophomina phaseolina (Tassi.) Goid was detected in 7 samples for the first time in Korea. Detailed descriptions of the habit character and pycnidial and pycnospore morphology of this fungus were described. Pycnidia of this fungus were not formed on agar media but they were formed on Water Agar Leaf Media under fluorescent light. M. phaseolina caused heavy reduction in seed germination and seedling stand of sesame and produced charcoal rot symptom on potato tubers. It was also detected from over wintered plant debris and diseased seedlings in the field.

• BMB Reports
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• v.43 no.5
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• pp.330-336
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• 2010

5-Aminolevulinate (ALA) is well-known as an essential biosynthetic precursor of all tetrapyrrole compounds, which has been suggested to improve plant salt tolerance by exogenous application. In this work, the gene encoding aminolevulinate synthase (ALA-S) in yeast (Saccharomyces cerevisiae Hem1) was introduced into the genome of Arabidopsis controlled by the Arabidopsis thaliana HemA1 gene promoter. All transgenic lines were able to transcribe the YHem1 gene, especially under light condition. The chimeric protein (YHem1-EGFP) was found co-localizing with the mitochondria in onion epidermal cells. The transgenic Arabidopsis plants could synthesize more endogenous ALA with higher levels of metabolites including chlorophyll and heme. When the $T_2$ homozygous seeds were cultured under NaCl stress, their germination and seedling growth were much better than the wild type. Therefore, introduction of ALA-S gene led to higher level of ALA metabolism with more salt tolerance in higher plants.

• Korean journal of applied entomology
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• v.14 no.1 s.22
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• pp.23-27
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• 1975

Occurrence of sheath rot rice caused by Acrocylindrium oryzae on indica varieties, IR lines and IR varieties was light to moderate in the field, whereas generally none of the recommended japonica varieties showed the disease. In general, percentage infection in the field agreed with that obtained from seed inoculation tests made in the laboratory. Culture filtrates of the fungus inhibited the sprouting of seeds of rice, barley, wheat, rye and rape. A new variety, Tongil obtained from a hybrid between japonica and indica was inhibited significantly more than was Jinheung. Conidial germination of Pyricularia oryzae was inhibited by the filtrate while no inhibitory effects were found on conidia of Cochliobolus miyabeanus.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.292-297
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• 1995

We developed an in vitro assay method for evaluating plant growth promotion and providing an evidence that the growth promotion is rendered by growth enhancing factors. The amendment of culture filtrates of Trichoderma harzianum T95 and Gliocladium virens G872 and G872B in Murashige and Skoog (MS) agar medium enhanced the cotyledon growth of cucumber in terms of fresh weight and primary leaf area of cucumber cotyledon cuttings, of which the treatment of G. virens G872B was the most effective. The mycelial culture filtrate of G872B was more effective in the growth promotion than its conidial germling filtrate. The addition of 1% sucrose in MS mineral medium with 0.1% culture filtrates of the antagonists (T95 and G872B) was optimum for enhancing the effect of the filtrates on the growth of cotyledon cuttings in vitro. When cucumber seeds treated with G872B, Pseudomonas putida Pf3 or the G872B-Pf3 mixture were planted in a greenhouse, the rate of seed germination, biomass of shoot and root, and yield of cucumber fruits were increased, especially by G872B or the G872B-Pf3 mixture. Correspondingly, cucumber fruit yields in early to middle-cycles of harvest were significantly greater in the plots of G872B than the control and Pf3-treated plots, and the final yield was highest in the plots of the G872B-Pf3 mixture applications.

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.213-218
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• 2008

Swertia chirata is an endangered gentian species that prefers to grow at higher altitudes. This ethnomedicinal herb is known primarily for its bitter taste caused by the presence of important phytochemicals that are directly associated with human health benefits. Due to a continuous loss of habitat and inherent problems of seed viability and seed germination, alternative strategies for propagation and conservation are urgently required to prevent the possible extinction of this species. We have formulated a reproducible protocol for the rapid propagation and conservation of this plant using leaves taken from in vitro shoot cultures. Direct induction of more than seven shoot buds per explant was achieved for the first time when the explants were placed on MS medium supplemented with $2.22{\mu}M$ N-6-benzyladenine, $11.6{\mu}M$ kinetin, and $0.5{\mu}M$ ${\alpha}-naphthalene$ acetic acid. Direct organogenesis was noted exclusively from the adaxial surface of the basal segments of leaves. Leaves closer to the apical meristem were more responsive than those farther away from the meristem. Plants raised through direct organogenesis were evaluated for their clonal fidelity by chromosomal analysis and DNA fingerprinting. Complete plants were successfully transferred to the field condition and produced viable seeds. Given the enormous potential of this age-old medicinal plant in terms of potential health-benefitting drugs, this protocol can be used for commercial propagation purposes and to initiate future genetic improvement studies.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.56-61
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• 1989

In the present paper, we intented to analyze and to compare the different seed dormancy of two legume plants, Albizzia and Cercis. We found two different types of seed dormancy: one type of dormancy in Albizzia seed was caused by the water impermeability, and other type of seed dormancy was found in Cercis and it was induced by inhibitors. We confirmed that the extract substances from Cercis seed seemed to have strong regulational functions on the inhibition of seed germination and primary root growth of lettuce seed.

• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.97-105
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• 2009

Seed storage lipids of plants, essential for seed germination as energy supplier, have been used for humankind and animal as nutrition sources. Fatty acids of vegetable oils have the characters appropriate for industry based on their chain length, the position and the number of double bonds. So they are used as raw materials for lubricants, cosmetics, soaps, paints and plastics or as energy source such as bio-diesel. However, there is a limit that applies vegetable oils from typical oil crops for industrial uses, mainly because of the mixture of five common fatty acids. Therefore, identification of unusual fatty acids for industrial uses from diverse plant resources and metabolic engineering to produce unusual fatty acids have been carried out in Arabidopsis as a model for the study of oilseed biology. Here, we discuss the unusual fatty acids for industrial uses, the genes synthesizing them in lipid metabolism, and the current limits in production of transgenic plants accumulating unusual fatty acid in their seeds. In addition, we describe our work on metabolic engineering of Brassica napus for the production of the unusual fatty acid ricinoleic acid in the seed, because of its industrial uses.

• Journal of Crop Science and Biotechnology
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• v.10 no.3
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• pp.141-146
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• 2007

The roots of Aristolochia elegans Mast.(Aristolochiaceae) are widely used in Mexican traditional medicine as a remedy for scorpion venom. Current experimental evidence supports its purported antidote properties. However, collection from the wilderness has lead to local extinction of natural populations. In order to contribute to species preservation, cultivation, and standardization of morphological and pharmacological properties, a micropropagation method was developed. This includes in-vitro germination of seeds to produce aseptic plantlets, induction of multiple budding, and acclimatization. The treatment with benzylamino purine(10 ${\mu}M$) induced the highest number of buds(3.1 on average) in both types of explants. On the other hand, indolebutyric acid(1.5 ${\mu}M$) caused the highest root index(11.8) per explant. One hundred percent of the micropropagated plantlets developed vigorously after the acclimatization process.

• The Plant Pathology Journal
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• v.36 no.1
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• pp.29-42
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• 2020

Acidovorax citrulli causes bacterial fruit blotch in Cucurbitaceae, including watermelon. Although A. citrulli is a seed-borne pathogen, it can cause diverse symptoms in other plant organs like leaves, stems and fruits. To determine the infection routes of A. citrulli, we examined the virulence of six isolates (Ac0, Ac1, Ac2, Ac4, Ac8, and Ac11) on watermelon using several inoculation methods. Among six isolates, DNA polymorphism reveals that three isolates Ac0, Ac1, and Ac4 belong to Clonal Complex (CC) group II and the others do CC group I. Ac0, Ac4, and Ac8 isolates efficiently infected seeds during germination in soil, and Ac0 and Ac4 also infected the roots of watermelon seedlings wounded prior to inoculation. Infection through leaves was successful only by three isolates belonging to CC group II, and two of these also infected the mature watermelon fruits. Ac2 did not cause the disease in all assays. Interestingly, three putative type III effectors (Aave_2166, Aave_2708, and Aave_3062) with intact forms were only found in CC group II. Overall, our results indicate that A. citrulli can infect watermelons through diverse routes, and the CC grouping of A. citrulli was only correlated with virulence in leaf infection assays.

• Journal of Plant Biology
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• v.14 no.3
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• pp.1-20
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• 1971

Ecological factors limiting Stipa pulchra have been determined in experimental gardens and at several sites in the hills south and east of Monterey, California. The Stipa pulchrafacies of Valley Grassland communities were found to be dominated by that species, though a total of 36 grasses and forbs were collected and identified. Basal area was not large, but aerial cover by Stipa alone averaged over 50 per cent. Across an ecotone between a Stipa association and the California Annual Type a sudden and dramatic change was recorded. Soil measurements there, and in other nearby areas, showed a much higher clay content with more available water and elemental phosphorus at the Stipa sites. Germination of Stipa seeds was high under all laboratory and field conditions, though growth of seeldings was highly variable. Seedlings grown in Stipa woil with an abundance of water were vigorous and reached anthesis the first year. In other soils they grew less, and when grown in competition with Avena fatua they scarcely grew at all. These findings indicate that when established on desirable soils, Stipa competes well and apparently precludes the dominance of Avena fatua and other large annual grasses. On the other hand, because of a lack of vigor in its seedlings, Stipa cannot reinvade the rich more friable soils on which it was once found, and on which it was shown to grow satisfactorily. This supports the contention that Sipa pulchra was the dominant grass through much of the Valley Grassland and Foothill Woodland, but also indicates that well-drained soils and those poor in mineral nutrients probalby never supported such associations.