• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.169-174
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• 1997

This study was conducted to obtain basic information needed to develop the effective weed control method by using thermal weeder which uses LPG as fuel. For survey of weed distribution in herb field, weed species were investigated at two kinds of herb field of Codonopsis lanveolata and Aster scaber located in Hoengseongkun and Hwacheonkun, Kangwondo. In Codonopsis lanveolata field, Digitaria sanguinalis and Persicaria viridis L were dominated. In Aster scaber field, Digitaria sanguinalis and Erigeron canadensis were dominated. In general, Grasses weeds in herb were more dominated than other broadleaf and Cyperaceae weeds. The treatments of $H_2SO_4$ in weed seeds were more effective for germination of several weeds, compared with that nontreated weed seeds. However, the rate of germination differed depending on weed species and tereatment time of $H_2SO_4. Also, viability of weed seeds was significantly affected by irradiation time and temperature. As the temterature and treatment time of irradiation increased, the rate of germination was decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.171-177
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• 1992

The purpose of this study was to compare the test methods for predicting field emergence of Lotus corniculatus and Trifolium pratense. Four seed lots of two herbage legumes were controlled deteriorated, accelerated aged before germination test and conductivity of each seed lot was determined. Those germination percent and conductivity of seed lots were compared with actual field emergence rate. Field emergence rate could be estimated by the controlled deterioration test ($R^2$=0.687), by the accelerated aging test ($R^2$=0.260), and by the conductivity test ($R^2$=0.238). A multiple regression equation for predicting field emergence rate(equation omitted) was estimated as (equation omitted)=-198.16 ＋ 2.3493X$_1$-1.5564X$_2$ ＋ 1.9812X$_3$where X$_1$, percent germination of controlled deterioration test ; X$_2$, percent germination of accelerated aging test; and X$_3$, conductivity of solute leakage in the conductivity test. Conclusively, unless multiple tests are not available, the controlled deterioration test was comparatively high efficient for predicting field emergence rate, however, the combined measurements of those three tests can enhance the efficiency.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.228-232
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• 1994

The influence of temperature, soil depth, burial duration, and soil moisture on the germination and viability of Galium spurium L. was studied in field and laboratory. Germination and maturing date were Oct. 20 and May 30, respectively. 1000 seed weight was 1.478g and seed color was dark brown. Optimum storage temperature to break dormancy was that $5^{\circ}C$, and germination rate of $10^{\circ}C$ was 81%, seed was not germinated at $20^{\circ}C$ or greater than $20^{\circ}C$. Optimum burial depth was 2cm and emergence rate was 40%. As bural duration in upland was longer, germination rate was increased, but buried seed of paddy land was died in a month. Optimum soil moisture content for germination was 25.3% in sand loam soil however seeds were not germinated above 43.6% or below 2.1%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.245-251
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• 1985

Distributions of seed weight were investigated with different seed sized peanut varieties planted at the same time, and germination and field emergence percentage, growth, and seed yield were compared among three seed sizes of four peanut genotypes. Field performance also was carried out to evaluate the effects of cotyledon removal on growth and yields in field with large and small seed-sized peanut varieties. The variation of seed weight of large seed-sized was wider than small seed-sized peanut variety. The larger seed showed the higher percent germination after 3 days cold treatment in laboratary and field emergence. The growth was not different with their sizes, while seed yield was related to seed size in small seed-sized genotypes. The growth of peanut such as main stem, internodes, and total branches was affected significantly by cotyledon removal, although the differences were not obvious after podding time, and in small seed-sized variety Oltangkong, the yields was decreased by cotyledon removal but not in large seed-sized variety.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.241-248
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• 2009

Varietal differences on viviparous germination of newly released rice varieties were investigated to provide selection criteria for the high quality rice production. Laboratory and field tests were conducted on 20 different rice varieties in 2007. Varieties which showed below 10% of viviparous germination at the laboratory test were Odaebyo, Hitomebore, Koshihikari, Hwasungbyo, Hopyongbyo, Ilpumbyo, Chuchungbyo when they were treated 35 days after heading (DAH) at the temperature of 25/$15^{\circ}C$ (day/night) for 8 days, and were Hitomebore, Koshihikari, Hwasungbyo, Hopyongbyo under diurnal temperature of 30/$20^{\circ}C$ (day/night). At the field test with artificial lodging, there were 12 varieties including Hopyongbyo, Hitomebore that showed lower viviparous germination below 10% when they were treated at 35DAH and measured 8 days after lodging treatment but there was only four varieties (Ilpumbyo, Hwasungbyo, Chuchungbyo, Hopyongbyo) when lodging treatment was made at the 45DAH. Among newly released rice varieties, viviparous germination rate of Hopyongbyo was below 10% and was 11 to 20% at Hithomebore and Samgwangbyo, 21 to 40% at Koshihikari, Odae-No.1, Josaengheukchalbyo, Chonghobyo, 41 and 60% at Suean-No.1, Whongwangbyo, Bosukchalbyo, and 61 to 90% at Gopumbyo when it was examined 8 days after lodging treatment at 45DAH.

• Environmental Analysis Health and Toxicology
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• v.14 no.4
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• pp.135-144
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• 1999

Environmental toxicities of priority water pollutants were evaluated by two selected bioassays, Lettuce seed germination/elongation test and Microtox acute toxicity test. Toxic chemicals (heavy metals, polycyclic aromatic hydrocarbons, and phenolic compounds) inhibited the germination rate and root elongation of Lettuce seed, as well as the bioluminescence of Microtox bacteria. When test biota were exposed to target chemicals, the sensitivity of Lettuce bioassay was relatively lower than that of Microtox bioassay. However, Lettuce bioassay may be a good candidate for prescreening the environmental toxicities of priority water pollutants, since the testing method with Lettuce seed was relatively easier and more economic than with Microtox bacteria. Toxicity tests were conducted to compare the validity and sensitivity of both bioassays for sediment from a small stream passed through urban area as well as leachate from a municipal solid waste landfill. From experimental results, we found that Lettuce test and Microtox test are compensated each other as a battery of bioassay for evaluating the environmental toxicities of field samples obtained from a small stream contaminated by pollutants.

• Animal cells and systems
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• v.9 no.2
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• pp.75-78
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• 2005

Fungicides and antagonists were tested for their efficacy in the management of fungal pathogens of watermelon. The fungal species in different genera were isolated from the seeds of watermelon and their vulnerability was assessed against an array of chemicals and bioagents. Among the fungal pathogens, Fusarium species were effectively controlled by Bavistin. Topsin also showed the promising effects against all the fungal pathogens, and Dithane M-45 effectively controlled Didymella bryoniae. Seed treatment with antagonists like Trichoderma harzianum and T. viride improved the seed germination, seedling vigour and reduced the incidence of seed-borne fungal pathogens. Bavistin and Topsin among chemicals increased significantly the seed germination and vigour index. Trichoderma harzianum showed its efficacy against all Fusarium species and even stood effective than Captan and Blitox. However, Pseudomonas fIuorescens also showed promising effect against Didymella bryoniae over fungicides. Under field condition, Topsin and Dithane M-45 showed better yield than Bioagents.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.78-83
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• 1986

To obtain the information about the reasons why hulless barley varieties generally have poor germination and emergence rate in the field, hulled and hulless isogenic lines were bred and used. The germination rates of hulless isogenic lines were 4-6 percent lower than those of hulled lines at artificial precipitation treatment, and seriously dropped down at 5 day precipitation treatment. As the thresher rotation speeds up 600 to 1,000 rpm, the differences of germination rate were 10 percent in hulled, but 22 percent in hulless lines. Also emergence rates of hulless lines became seriously low at deep seeding. The emergence rates of hulless isogenic lines became low in the order of deep seeding, high speed thresher, and rain-fall. These results suggest that barley breeders especially for hulless varieties should plan their breeding programs to improve the emergence rate or seedling vigour in the field.

• Asian Journal of Turfgrass Science
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• v.14 no.1
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• pp.251-256
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• 2000

The purpose of this study is to select the appropriate herbicide, which is needed to control the bentgrass in kentucky bluegrass(Poa pratensis) fairway effectively. The best control of bentgrass was observed at /$0.3mL\m^2$ of dithiopyr applied on Kentucky bluegrass. A field experiment was conducted to determine the priming effects on seed germination of Kentucky bluegrass. Ground covering rates by turfgrass were investigated under field conditions for 70 treatments by thirty days after treatment. The solid matrix priming(SMP) treatments on Kentucky bluegrass reduced the number of days requited for emergence and improved final cover ratings. Primed seeds of Kentucky bluegrass (incubated for five days at $20^{\circ}C$) resulted in most rapid germination and covering rate.

• The Korean Journal of Ecology
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• v.11 no.2
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• pp.65-76
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• 1988

A number of laboratory and field experiments have performed with aqueous extracts from fresh leaves, fallen leaves and roots of Pinus rigida in order to investigae the effetct of the pine tree. The results obtained found its inhibitive effect on the germination and growth of tested species. Though relative germination ratio of the species was somewhat lower than the control plot, severe inhibition was observed in relative dry weight ration, These results were more obvious in aqueous extracts than in the case of leachates and similar results were also confirmed by field bioassays on the forest soil of P. rigida. Therefore, to find out the inhibitory sybstancesm 14 different kinds of KDICical substances were isolatd from the leaved of the tree by chromato-graphy and nist if them were confirmed to be phenoic compounds, The growth of lettuce was inhibition was observed in the concentration of less than 5X10-3M soluton. Phenolic compounds are assumed the substance related to the allelopathic effect of P. rigida.