• Weed & Turfgrass Science
• /
• v.4 no.3
• /
• pp.219-224
• /
• 2015

This study was conducted to evaluate the effect of herbicidin, new natural herbicidal substances, derived from soil actinomycetes Streptomyces scopuliridis. Several weed species were subjected to examine the germination inhibition and herbicidal activity at the concentration from 100 to 2,000 ppm. There was no selectivity in germination inhibition and herbicidal activity against crops. Germination of Echinochloa oryzoides, Digitaria ciliaris, Abutilon theophrasti and Amaranthus retroflexus was inhibited completely when 7.81 ppm of extract was treated in petri dish. Pre-emergence application of herbicidin in soil condition showed low inhibition against weeds. However, post application of herbicidin in green house resulted in the necrosis of weeds at the concentration of 2,000 ppm. A. retroflexus was sensitive to herbicidin at the low concentration of 62.5 ppm, whereas E. oryzoides was tolerant to lower concentration of herbicidin until it became withered at the concentration of 2,000 ppm. In conclusion, herbicidal substances derived from S. scopuliridis herbicidin, which is consisted with herbicidin A and B, have dominant effect on germination and growth inhibition. On the other hand, herbicidin was insufficient to control gramineous weeds. In future, it will be needed to develop the combination of herbicidin with other herbicide or compounds to control gramineous weeds as well.

• Korean Journal of Weed Science
• /
• v.12 no.1
• /
• pp.46-51
• /
• 1992

The survey of weed population in paddy field was carried out to invegstigate the weed group on 340 fields in Kyonggi Area in 1991. The weed species observed include 4 species of grasses, 7 species of sedges, and 14 species of broadleaf weeds, and the ratio of annual weed vs perennial weed was 25 : 75. Major dominant weed species were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli and Cyperus serotinus. The dominant weed species in South Plain Region were Echinochloa crusgalli, Eleocharis kuroguwai, Sagitariu trifolia, Cyperus strotinus, in West Coast Region were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli, Cyperus serotinus, in East Interior Region were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli, Cyperus difformis and were Sagitaria trifolia, Eleocharis kuroguwai, Echinochloa crusgalli and Monochoria vaginalis in North Region. The dominant weed species in Normal and Poorly drained soil were Eleocharis kuroguwdi, Sagitaria trifolia, Echinochloa crusgalli and Cyperus serotinus and were Scirpus maritinus, Cyperus serotinus, Echinochlod crusgalli and Myriophyllum verticillatum in Saline Soil. More and many weeds were growing in single cropped field than double cropped field.

• Korean Journal of Agricultural Science
• /
• v.33 no.2
• /
• pp.123-127
• /
• 2006

This study was carried out to compare growth and yield performance for soil conditions at the Maize Genetics and Breeding Lab. in Chungnam National University. The waxy hybrid corn in the drained soil of paddy field showed higher fresh yield per 10a and 100-kernel weight per plant than control. The average dry yield of drained and drainless soil were 804kg/10a and 498kg/10a compared with a control (751kg/10a), respectively. The waxy hybrid corn in the drained soil also had better good stand and stay green characteristics than drainless soil condition, and showed moderately resistance to water stress and weed. Vegetational feature of weeds was characterized as the prevalence of Acalypha auatralis, Echinochloa crus-galli, Persicaria hydrpopiper in drained paddy soil and Persicaria hydrpopiper, Acalypha auatralis, Echinochloa crus-galli in drainless paddy soil, and Echinochloa crus-galli, Acalypha auatralis in upland soil.

• Korean Journal of Weed Science
• /
• v.4 no.2
• /
• pp.135-142
• /
• 1984

To obtain the basic information for weed management in polder land, a colligated assessment on weed distribution and it`s plant sociological indices on Gyewha polder land were arranged. At the situation of assessment, the Gyewha polder land was reclaimed with aim with paddy-rice production. As a result of reclamation, the salinity of most soil samples were below 0.3%, and acidity ranged from pH 5.5 to 6.5. Total weed species were counted as much as 17 species (3 gramineae, 7 cyperucese, and 8 broad-leaved species), and a most dominant species, Scirpus maritimus, were succeeded with Monochoria v., Eleocharis a., and Cyperus d., etc. by reclamation. Declining of soil salinity and soil pH, the number of weed species, individuals, biomass, species diversity, evenness, sociability index were increased, but the population particularity was weaken in tendencies. By developing of reclamation, the weed species which is summer annual broad leaf, wind and water disseminating, and tussock formed species are increased instead of salt-resistant, perennial cyperus, and rhizomatous extending species.

• Weed & Turfgrass Science
• /
• v.2 no.1
• /
• pp.30-37
• /
• 2013

The objective of this research was to understand herbicidal activity of essential oils isolated from leaves of pine (Pinus densiflora), nut pine (Pinus koraiensis), larch (Larix kaempferi) and khingan fir (Abies nephrolepsis) in Korea. In a seed bioassay, essential oils of nut pine, larch and khingan fir inhibited the growth of rapeseed (Brassica napus) seedlings by 50% at 4,766, 1,865, $5,934{\mu}g\;ml^{-1}$, respectively, however, that of pine did not show any herbicidal effect. In a green house experiment, fall panicum, Southern crabgrass, sorghum, barnyardgrass, quackgrass, black nightshade, Indian jointvetch, velvet leaf, and Japanese morningglory were controlled in 24 hours by the foliar application of 10% essential oils from pine, nut pine, larch and khingan fir. The treated plant parts showed burndown effect, however, new shoots appeared 3 days after treatment. Results of GC-MS analysis showed that essential oils from pine, nut pine, larch and khingan fir contained 16, 25, 25, and 16 compounds, respectively, with hydrocarbons, alcohols, ketones, and esters. The major compounds of the essential oils were 3-carene, bornyl acetate, camphene, limonene, ${\alpha}$-pinene, ${\beta}$-pinene and ${\beta}$-phellandrene.

• Korean Journal of Weed Science
• /
• v.2 no.2
• /
• pp.152-159
• /
• 1982

To investigate the effect of isoproturon (N,N-dimethyl-N-4-isopropyl phenyl urea) on weed-killing, crop injury and yield of barley, several experiments were conducted by application time, dosage, cultivars and soil texture. For the effective control of weeds the optimum application time was foliage application after winter. Alopecurus aequalis SOBOL was effectively controlled when isoproturon should be applied at three to four leaf-stage and most annual broad-leave weeds emerged through winter and spring could be controlled when applied even at five to six leaf-stage. But among the broad-leave weeds Vicia amoena Fisch. was resistant to isoproturn. The optimum application rate of isoproturon was 240g-300g/10a (prod.). Among 11 cultivars of barley and wheat, phytotoxicity of Olmil, Jokwang and Rye was slighter than that of the other cultivars when isoproturon was treated by foliage application after winter. At the time of foliage application after winter, the variation of phytotoxicity and effectiveness was a little despite the difference of soil texture and the grain yield of barley was higher in the plots treated 240-300g/10a than in other treated plots.

• Korean Journal of Weed Science
• /
• v.31 no.3
• /
• pp.240-249
• /
• 2011

The potential of juglone a plant naphthoquinone as a natural herbicide on new target, 7-keto-8-amino pelargonic acid synthetase (KAPAS) in the early step of biotin biosynthesis pathway, was performed in vitro and in vivo. Juglone effectively inhibited KAPAS activities in vitro and the $IC_{50}$ was $9.5{\mu}M$. Foliar application of juglone showed very good herbicidal activity to the eight-tested weed species. Among them, Solanum nigrum was completely controlled at a concentration of $250{\mu}g\;mL^{-1}$ with main symptoms of desiccation or burndown. Digitaria sanguinalis and Aeschynomene indica were also sensitive to juglone treatment. All eight weed species were controlled by 90~100% at a concentration of $500{\mu}g\;mL^{-1}$. However, soil application of juglone to Digitaria sanguinalis did not show any herbicidal symptoms. Cellular leakage from cucumber leaf squares treated with juglone increased depending on the concentrations increased from 6.25 to $100{\mu}M$ after 24 hours incubation with or without light. However, chlorophyll loss in cucumber leaf squares was negligible. Biotin supplements significantly rescued the inhibition of germination rate of Arabidopsis thaliana seeds previously inhibited by the juglone. Our results suggest that the juglone is a possible environmental friendly herbicide candidate with a new target KAPAS inhibiting activity.

• Korean Journal of Weed Science
• /
• v.7 no.1
• /
• pp.3-11
• /
• 1987

The study was conducted to identify growth habit of Monochoria vaginalis gathered from three different locations (Suweon, Jeonju and Milyang). The plant height, number of leaves and dry weight of M. vaginalis gathered from three different locations were greatly affected by the seeding dates. The earlier the seeds of M. varginalis sown, the greater M. vaginalis grew, In general, the earlier seeding dates produced significantly longer plant height, number of leaves and dry weight than those of later seeding dates, showing no difference in the collection of weed seeds in different locality. The earlier seeding dates resulted in the earlier flowering, but the interval between dates of seeding and flowering decreased progressively as the seeding times were delayed. Seed production was not significant among three locations and but seeding date on June 15 produced th highest seed production as compared with other seeding times. No. of flowers and capsule per pot among yield components were two major factors affecting seed production.

• Weed & Turfgrass Science
• /
• v.1 no.4
• /
• pp.64-68
• /
• 2012

Creeping bentgrass (Agrostis stolonifera L.) is one of the highest maintained turfgrass but often problematic especially for Kentucky bluegrass fairway. Mesotrione is one of selective herbicide that is firstly registered for corn (Zea mays L.) and provides preemergence and postemergence control of broadleaf and annual grassy weeds. Although mesotrione is effective to eradicate area contaminated by creeping bentgrass, protracted time is required to recover damaged area by rhizome extension of Kentucky bluegrass. Overseeding is typically used to fill bare or damaged areas using appropriate turf species to create a uniform turfgrass surface. The objectives of this study were to evaluate mesotrione and seeding rate effects to recover Kentucky bluegrass contaminated by creeping bentgrass. Six treatments consisted of three mesotrione rates and two Kentucky bluegrass seeding rates. The mesotrione rate were 0, 0.05 and 0.10 m $ml^{-2}$. Two seeding rate of to Kentucky bluegrass 'Midnight' were 15 and 30 g $m^{-2}$. Mesotrione application and Kentucky bluegrass overseeding at the same time is helpful to damage creeping bentgrass but not for establishment of Kentucky bluegrass to refill damaged area. To maximize mesotrione effects, temperature above $20^{\circ}C$ would be recommended based on this study.

• Korean Journal of Weed Science
• /
• v.10 no.4
• /
• pp.294-304
• /
• 1990

For the survey of weed distribution in the cultivated upland of Korea, weed species were investigated at 2 field by crop of 2 myon per kun in 81 kun selected among the 139 kun of the whole country. 232 species in 46 families were observed, totally. From among the result, 165 species in 39 families the in winter crop field, 189 species in 41 families in the summer crop field were classified. 122 species in 34 families were emerged the from the upland crop field of the whole season. Further more, in the 10 dominant weed species which emerged from upland crop field, Alopecurus aequalis, Chenopodium album, slellaria media, Galium spurieum, Capsella bursa-pastoris and Rorippa islandica were dominated in the winter upland and paddy field, and that Erigeron canadensis, Cyperus amuricus, Equisetum arvense and Arenaria serpyllifolia were dominated in the winter upland field, additionally. Stellaria alsine, Bothriospermum tenellum, Trigonotis peduncularis and Polygonum arviculare were dominated in the winter cropping on drained paddy field, additionally. In the summer crop field, Digitaria sanguinalis, Portulaca oleracea, Acalypha australis, Echinochloa crus-galli, Setaria viridis, Persicaria hydropiper, Amaranthus lividus, commelina communis, Chenopodium album and Cyperecs amuricus were dominated.