• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.6
• /
• pp.684-696
• /
• 1995

A mutant for chalky endosperm and genetic male sterility (GMS) was newly developed in rice. The two characters were found to be controlled by single recessive gene which has pleiotropic effect, indicating that chalky seeds should be GMS seeds in segregating populations. Chalky seeds showed the same shape and size as normal seeds. However, starch composition of central part of endosperm was looser and shape of starch granules was rounder compared with normal endosperm, resulting in significantly lower grain weight, absolute density and grain hardness in chalky grains than in normal ones. Amylose content and gel consistency of chalky grains were much lower and harder, respectively. Male sterile plants showed much shorter plant height, poorer panicle exsertion and lesser panicle number compared with normal plants. Microspore abortion stage in pollen developmental process was observed as before meiosis. Male sterility of the mutant was stable regadless of temperature and day length. A system breeding hybrid rice using this mutant was discussed, comp ring with other systems utilizing cytoplasmic-genic male sterility(CGMS) and environment sensitive GMS(EGMS). Separation of GMS seeds in mixed seed bulks by specific gravity (1.14∼1.16g / cm3) was successful about 85∼90%. But some mixed normal plants were seemed to be easily removed by the apparent difference in growth characters at seedling stage. The highest natural outcrossing rate of this GMS line was as 17.3 % in a plot treated with 2-row pollinator, I-row GMS, and GA3 + cutting of flag leaf + pollen-scattering by rope.

• Korean journal of applied entomology
• /
• v.1
• /
• pp.42-46
• /
• 1962

1) The purpcse of the present study is to investigate the effects of culture filtrates of Fuarsium oxysporum f. vasinfectum which is known to produce wilt toxin (fusaric acid) on the germination of host plants (sesame, cotton) and non-host plants (wheat, rice). 2) The experiment on the germination of sesame, cotton, wheat and rice seeds in the seed beds separately added with culture filtr ates of 10 differential strains of Fusarium oxysporom f. vasinfectum demonstrated that culture filtrates of most strains of the fungus inhibit or retard the germination of seeds of 4 plants used in this study while those of a few strains do not give notable influence on the germination of seeds of those plants. a) Culture filtrates of strain 201 of the fungus strongly inhibited the germination of seeds of those plants in nearly same degree, but culture filtrates of the other strains, 281, 321, etc., showed remarkable differences in the toxicity inhibiting or retarding the germination of the seeds of those plants. b) In general, sesame seeds are greatly susceptible, wheat and cotton seeds are moderately susceptible and rice seeds are resistant to the toxicity of culture filtrates of the fungus. 3) In the soil containing a number of differential strains of Fusarium oxysporum f. vasinfectum, the germination of seeds and also the growth of seedlings of non-host plants are possibly checked by the toxic substance, fusaric acid produced by the fungus.

• Korean Journal of Medicinal Crop Science
• /
• v.3 no.1
• /
• pp.66-70
• /
• 1995

These experiments were conducted to investigate the growth and characteristics of Adenophora triphylla DC. seed, and effects of some pretreatments and light condition on the gemination of it. The results were as follows. Seed coat was soft and white at 30 days after flowering, but it became hard and brown from 40 days. The 1,000 grain weight was 247mg at 40 days after flowering and high at 50 days as 268mg, and decreased from 60 days. Germination percentage was highest at 100ppm $GA_3$ treatment for 24 hours as 96.7% and 88.3% at moistured treatment at $0^{\circ}C$ for 7 days, but only 40% at control. Adenophora triphylla. seed was light germinator, but it could be germinated 80% even under dark condition if $GA_3$ was treated 100ppm for 24 hours. The optimum temperature of germination in Adenophora triphylla. seeds was $25^{\circ}C$.

• Korean Journal of Plant Resources
• /
• v.20 no.5
• /
• pp.481-489
• /
• 2007

Present experiments are conducted to study the seed viability and optimum germination temperature of Polygonatum odoratum var. pluriflorum that is known to have low germination ability and long germination duration. To enhance germination rate, various growth regulators and inorganic salts were employed. Low germination rate was obtained with 4 year old seeds, but not with $1{\sim}2$ year old seeds. The seeds germinated very well under $22{\sim}25^{\circ}C$ and germinated speed was rapid. Especially, $1{\sim}2$ year old seeds germinated at $25^{\circ}C$ showed $70{\sim}71.2%$ germination rate. Priming treatments using $GA_3$, IAA, NAA, kinetin, $KNO_3$, $KH_2PO_4$, $Ca(NO_3)_2$ were effective compared to control except BA. 1 year old seeds treated with $GA_3$ 0.5 mM and IAA 1 mM showed 96% and 93% germination rate, respectively.

• Journal of Korean Society of Forest Science
• /
• v.55 no.1
• /
• pp.47-54
• /
• 1982

Soft X-ray photography was used to study some characters of seeds, such as fullness, damage by blight and harmful insects and degree of mechanical damages, degree of development of embryos and endosperms, size and position of cotylendons, existence and position of twin seed. Thirty nine species of woody plants (31 angiosperms and 8 gymnosperms)and four species of herbs were examined in this study. The results showed that through the mechanism of the selective sensitivity of seed structure of soft X-ray, seed characters mentioned above could be recognized regardless of size of seeds and thickness of seed coat. We concluded that it is possible to use soft X-ray photography reliably to find out the various characters of seeds.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.4 no.1
• /
• pp.12-17
• /
• 2002

This study identified the physiological characteristics of Alnus firma seedlings collected from air polluted industrial complex of Yeosu area with inoculation of nitrogen-fixing nodule. A. firma individuals resistant or sensitive to air pollution stress at the study area were selected. Seeds of the individuals were sown in a pot and inoculated with the nodules collected at the same area about 3 weeks after germination. To compare the inoculation effects, photosynthesis was measured among the A. firma seedlings under 12 inoculation combinations of seed sources and nodule sources. Photosynthetic activities of seedlings from resistant mother trees were obviously higher than those from sensitive mother trees. In general, the seedlings inoculated with nodule of sensitive trees, showed a worse physiological trend on every combination. In this study, inoculation effect was less important factor than seed sources to photosynthetic activities of A. firma. This physiological characteristic seemed to be determined by seed sources rather than nodule sources.

• Current Research on Agriculture and Life Sciences
• /
• v.7
• /
• pp.41-46
• /
• 1989

The seeds of Malus sieboldii were collected in late fall of 1988 and stored in cold stratification condition for 15 weeks. Growth regulators such as $GA_3$, BA and ABA were treated to the seed to know germination capacity and seedling growth. The results were as follows. 1) Higher germination was achieved in $GA_3$ and BA plots, But ABA treatment showed lower germination percentage and physiological dwarf and also induced to the secondary dormancy condition in partly. 2) Average length of time for germination was delayed over 2 days in ABA plot when comparing with the other plots. 3) Average length of plumule and radicle also was inhibited by ABA treatment. This means lower seedling vigor. 4) Fresh and dry weight of the seeding were higher in BA plot while ABA plot was lower and undesirable seedling was produced. From above mentioned results, it is believed that ABA treatment to the seed induced the secondary dormancy and physiological dwarf pattern. Therefore, utilization of BA can be produced the normal seedling, the authors believed.

• 농업기술회보
• /
• v.49 no.2
• /
• pp.33-34
• /
• 2012

벼 무논점파란 무논상태에서 종자를 점파형식으로 파종함으로써 파종의 균일도를 높이고, 입모 및 벼 생육이 고르게 자랄 수 있게 한다. 따라서 벼 직파를 하되, 입모 및 벼의 생육을 안정적으로 도모하여 마치 기계이앙으로 재배한 벼와 비슷한 효과를 보이는 벼 무논점파 재배기술을 농가현장에서 실증한 결과와 농민방응 및 기술보급 경향을 알아보자.

• Korean Journal of Weed Science
• /
• v.8 no.3
• /
• pp.309-316
• /
• 1988

Several experiments were conducted to investigate the achene viability and growth characteristics of Eclipta prostrata (L.) L. No dormancy and no after-ripening requirement were found for E. prostrata achenes. When achenes were stored at room temperature, germination did not decrease with up to 5 months storage. Large differences in loss of viability of E. prostrata achenes occurred when different dehydration methods were used. Immediate dehydration resulted in high viability, but slow dehydration resulted in severe loss of viability. Achene viability at shallow burial depths (5 and 10 cm deep) was lower under upland soil conditions than under lowland soil conditions. Seedling growth was greatly reduced when flooding to a depth of 10 cm occurred at or before the 4-leaf stage. Flooding after the 4-leaf stage stimulated stem elongation. Branching started from the second week and usually terminated at the tenth week. Leaf size was determined by the branch which are related to the assimilate supply. Flowering of E. prostrata started during the fifth week after emergence, and mature achenes were produced from the sixth week. Ten to 14 days were needed for the achenes to mature. About 14,000 achenes were produced on each plant. Achene production per week increased from the sixth week to the tenth week and thereafter it declined. The average number of achenes per inflorescence decreased with delay in flowering.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.31 no.4
• /
• pp.493-498
• /
• 1986

In order to evaluate the effect of various cultural methods developed during last 30 years on grain yield of wheat and barley and structure of plant stand for uptake of nutrient and water, solar energy use and com-petitive capacity with weed, 10 kinds of cultural practices were compared in the clayey upland soil. Row fertilization is more effective for uptake of N,P and K than rotary fertilization. Weed occurrence was deeply related with width of non-seeded area in the row and affected yield decrease. Winter injury was more serious in the cultural practices with thick plant community than in those with isolated individual plant. Root distribution was more remarkable in drill seeding or broadcasting than row seeding and had positively correlated with water consumption of barley.