• Korean Journal of Agricultural Science
• /
• v.10 no.2
• /
• pp.269-276
• /
• 1983

Out of 50 seed samples of Sesamum indicum L. tested, Alternaria sesami and Corynespora cassiicola were detected in 29 samples and 38 samples, respectively. Heavy infection of A. sesami and C. cassiicola caused seed rot and seedling blight on water agar as well as in pots. In case of light infection the seed germinated showing elongation of the radicle and hypocotyl, but soon light brown or dark brown lesions appeared at certain parts of the shoot and root where sporulation of the fungi was observed after prolonged incubation in moisture. Four seed disinfectants were compared for the control of seed-borne infection of A. sesami and C. cassiicola. Complete control of seed-borne infection of C. cassiicola was obtained by seed treatment with Benlate T and Homai and seed treatment with Busan 30 was found superior to control seed-borne infection of A. sesami.

• The Plant Pathology Journal
• /
• v.38 no.4
• /
• pp.313-322
• /
• 2022

Seed-borne pathogens in crops reduce the seed germination rate and hamper seedling growth, leading to significant yield loss. Due to the growing concerns about environmental damage and the development of resistance to agrochemicals among pathogen populations, there is a strong demand for eco-friendly alternatives to synthetic chemicals in agriculture. It has been well established during the last few decades that plant seeds harbor diverse microbes, some of which are vertically transmitted and important for plant health and productivity. In this study, we isolated culturable endophytic bacteria and fungi from soybean seeds and evaluated their antagonistic activities against common bacterial and fungal seed-borne pathogens of soybean. A total of 87 bacterial isolates and 66 fungal isolates were obtained. Sequencing of 16S rDNA and internal transcribed spacer amplicon showed that these isolates correspond to 30 and 15 different species of bacteria and fungi, respectively. Our antibacterial and antifungal activity assay showed that four fungal species and nine bacterial species have the potential to suppress the growth of at least one seed-borne pathogen tested in the study. Among them, Pseudomonas koreensis appears to have strong antagonistic activities across all the pathogens. Our collection of soybean seed endophytes would be a valuable resource not only for studying biology and ecology of seed endophytes but also for practical deployment of seed endophytes toward crop protection.

• Journal of Ginseng Research
• /
• v.16 no.2
• /
• pp.129-137
• /
• 1992

This study was carried out to investigate the localization of lipids and lipase activity with lipid staining and cytochemical technique in endosperm cells of Panax ginseng C.A. Meyer seed. In endosperm cells of indehiscent seed, protein bodies facing the umbiliform layer are different in electron density during the various degraded processes. Gradually, protein matrix near the cell wall was lysed and electron lucent inclusions appeared on umbiliform layer. The protein body with high electron density and the spherosome with low electron density were observed in endosperm cells. As a result of lipid staining, electron density of spherosome is more intense than those of the protein matrix within the protein body in endosperm cells of indehiscent seed. Free spherical spherosomes within the umbiliform layer have a high electron density. The spherical spherosomes were more electron densed and were uniform in comparison with the cytoplasmic proteinaceous granules in endosperm cells of seed with red seed coat. The major component of spherosome was determined to be lipid. Lipase activity occurs in the spherosome and near the endosperm cell wall facing the umbiliform layer. Cytochemical reaction products of lipase were observed in the spherosome membrane and in the inner regions of spherosome. After protein bodies were digested, lipase activities were observed in free spherosomes and near the cell wall of endosperm cells. Umbiliform layer composing of fibrillized wall and digested materials of the endosperm cell showed a little lipase reaction products.

• 한국생태학회:학술대회논문집
• /
• 2002.08a
• /
• pp.79-82
• /
• 2002

Main attackers on pine seeds on the forest floor were investigated in Korea. Damage on pine cones begins in early stage of cone formation, especially by squirrel and Korean squirrel. The above animals left Kayak-like hulls of seed on rocks and fallen tree trunk. Field mice also left the same shape of Kayak-like hulls. But birds including doves and peasants left large shreds with longitudinal cracks or seed cup trace. Most of seeds on the leaf litters as well as under the fallen leaf were consumed by fold mice and birds. Especially fold mice found the seeds under fallen leaves and consumed all of them.

• The Korean Journal of Ecology
• /
• v.25 no.4
• /
• pp.213-216
• /
• 2002

Main attackers on pine seeds on the forest floor were investigated in Korea. Damage on pine cones begins in early stage of cone formation, especially by squirrel and Korean squirrel. The above animals left Kayak-like hulls of seed on rocks and fallen tree trunk. Field mice also left the same shape of Kayak-like hulls. But birds including doves and peasants left large shreds with longitudinal cracks or seed cup trace. Most of seeds on the leaf litters as well as under the fallen leaf were consumed by field mice and birds. Especially field mice found the seeds under fallen leaves and consumed all of them.

• Clinical and Experimental Reproductive Medicine
• /
• v.49 no.2
• /
• pp.110-116
• /
• 2022

Objective: Sperm vitrification leads to the production of reactive oxygen species (ROS) that can damage the functional parameters of sperm. The present study aimed to investigate the antioxidant effect of Nigella sativa extract on motility, plasma membrane function, mitochondrial membrane potential (MMP), DNA damage, and intracellular ROS production. Methods: A total of 20 sperm samples were used. Samples were divided into six experimental groups, including groups with aqueous extract from N. sativa seeds at concentrations of 1% to 6%, a cryopreserved control group, and a fresh control group. Results: Statistical analysis showed significantly higher total sperm motility at concentrations of 3% to 6% than in the vitrified semen control group. Additionally, progressive motility and all motion characteristics at all concentrations were significantly higher than in the vitrified semen control group. The presence of N. sativa seed extract also improved the quality of the sperm parameters assayed in all experimental groups (1%-6%; intracellular ROS production, DNA damage, MMP, and sperm membrane function) compared to the control group. Conclusion: Higher concentrations of N. sativa led to improvements in all sperm parameters and sperm quality. These findings indicate that N. sativa seed extract is effective for improving the quality of sperm after vitrification.

• Korean journal of applied entomology
• /
• v.22 no.2 s.55
• /
• pp.130-137
• /
• 1983

A wide variety of pathogens are known io be seedborne, carried either as infectious mycelium internally or as contaminants on the seed coat. When seed is infected with a pathogen, the seed nay be rendered nonviable or it may remain viable but produce weak seedling. In some cases, the Infected seedling nay not be severely weakened, but nay serve as a source of primary inoculum within a community of plants. A recent problem nay be the dissemination of seedborne pathogens occurring as a result of the massive movements of seed, as a part of the 'Green revolution' Disease of great danger to agriculture may be introduced with seed from other parts of world. Seed treatment with organic mercury compounds in liquid form had become popular since about 1955. Organic mercury compounds contributed considerably to the increase in production of many crops and vegetables. In 1975, however, the use of organic mercury compound was forbidden because of doubts regarding their residual mammalian toxicity in agricultural products. Benomyl-thiram mixture, thiophanate methyl-;hiram mixture and TCMB have now been registered as seed disinfectants for the use of rice blast, brown spot and Bakanae disease. Oxathiinsthiram mixture has been registered as seed disinfectant for barley and wheat loose smut and leaf stripe of barley. Agricultural techniques have made such rapid progress that the nursery methods changed from the use of paddy nursery to box nursery designed for machine-transplanting. The spread of rice transplanting machines has caused increase of seedborne diseases. Among seedborne diseases, Bakanae disease has remarkably increased and causes much damage recently. In order to counter this trend, seed disinfectants must also be diversified. First, effective non-selective disinfectants need to be developed, and second, appropriate control methods always need to be prepared in parallel with the development of new techniques for cultivation.

• Korean journal of applied entomology
• /
• v.23 no.2 s.59
• /
• pp.126-131
• /
• 1984

Twenty one fungi were detected from 26 rice seed samples obtained from Yeongnam Crop Experiment Station, Honam Crop Experiment Station, Chungnam Provincial Office of Rural Development and farmers of Chungnam Province. Gerlachia oryzae was one of frequently detected fungi with $1.0\~45.0\%$ of detection ratio from 22 rice seed samples. The deep-freezing method was selected as the most suitable for routine seed health testing when the blotter method, deep-freezing method and agar plate method were evaluated for efficiency of detecting seed-borne G. oryzae from rice seeds. Our data obtained by seed component plating technique suggested that G. oryzae was present not only on chaff, in endosperm and in seed coat, but also in the embryo. Seed-borne G. oryzae caused seed rot, seedling blight and symptom of brownish discoloration on coleoptile primary and 2nd leaf when the infected seeds were sown in agar of test tube or in soil.

• Korean Journal of Breeding Science
• /
• v.42 no.5
• /
• pp.439-447
• /
• 2010

Riptortus clavatus, one of the many insects in major crops, damages pods and seeds, which reduces seed vigor and viability in soybeans. This study was conducted to examine the effect of diversely damaged seeds by R. clavatus on seed germination and seedling emergence and to determine the association of damaged seed with quality and yield of soybean sprouts. All seeds damaged by R. clavatus significantly (P<0.05) reduced seed vigor as measured by the rates of seed germination, germination speed, and seedling emergence. Mean seed germination rate of non-damaged seeds in sprout-soybean varieties was 97.8%, whereas the rates of seeds damaged at different levels, 31-50% and 51-80%, were 23.0 and 5.4%, respectively. The rates of seedling rot and abnormal, incomplete germination significantly (P<0.05) increased as the amount of seeds damaged by R. clavatus increased to 5, 10 and 15% against the total seeds for sprout production. Yield of soybean sprouts from seeds damaged at different levels decreased up to 13% as compared to that in normal seeds. In customer preferences on soybean sprout produce, 84% of customers participated in survey preferred to purchase sprouts from seeds with 5% of damaged seeds, but sprouts produced from seeds with 15% of damaged seeds were intended to purchase only by 22% of the customers. Areas of the seed damaged by R. clavatus were readily infected by pathogens as the seed germinated, resulted in deteriorated quality and reduced yield of sprout produce.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.2
• /
• pp.139-150
• /
• 1993

This experiment was carried out to investigate the difference of seed vigor according to seed size, and the physiological aspects and physico-chemical phenomena related with seed vigor in soybean cultivars. Portion of seed coat and radicle to entire seed was much higher in cultivars with small seed than with large. Seed coat rate ranged 7.9% to 9.9%, and radicle 2.5% to 3.3% in small seed group, Whereas in large seed, seed coat rate did 5.5-6.4% and radicle, 1.5 to 2.1%. After accelerated aging treatment, there are significant difference in germination ability between seed size. The germination rate after aging ranged 47 to 80% in cultivars with small seed, but in large seed, only 14 to 24%. After seed was carried out dehydration in incubator at 25 after soaking for 6 hours, the moisture content of seed in drying for 12 hour was 25.5% in small seed, while it was 51% in large seed. Electrical conductivity, leaching soluble nitrogen and sugar content were higher in large seed cultivars. Besides, cotyledon damage after soaking was occurred frequently in large seed cultivars, and seed vigor within same cultivars was higher in small seed than large.