• Korean Journal of Soil Science and Fertilizer
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• v.38 no.3
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• pp.134-141
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• 2005

Cultivation of winter cover crops and its soil utilization for summer main crops in slope upland is very important at the respects of diminution of soil erosion and non-point pollution source. The effects of cover crop, hairy vetch as no-tillage or conventional tillage on prevention of soil erosion and reduction of chemical nitrogen fertilization were investigated in the slope upland with whiter clover living mulch (partial tillage) in Suwon for three years and with rye (conventional tillage) in Hongcheon for two years, respectively. In Suwon, amounts of soil lost by rainfall runoff decreased as much as 90% by hairy vetch-no tillage (HV-NT), white clover-partial tillage (WF-PT) together with the decrease of rainfall runoff compared to winter fallow with conventional tillage (WF-CT). In addition, amounts of weed also decreased as much as 80-90% by HV-NT and WF-PT. Corn yield decreased much at the plot of WF-PT mainly due to competition for soil water and nutrients between clover and corn at the early corn growth stage. On the contrary, corn yield increased by HV-NT compared to WF-CT regardless of weed control. In Hongcheon, amounts of soil eroded during winter season before corn seeding were reduced as much as 95% by cultivation of hairy vetch and rye compared to winter fallow. Amount of soil eroded during waxy corn growing season was reduced as much as 98% by HV-NT compared to WF-CT. Also, soil incorporation of hairy vetch and rye as green manure with conventional tillage at corn seeding time could reduce soil erosion as much as 70% compared to no soil cover with conventional tillage. Ear yields of waxy corn were increased 10% higher at hairy vetch green manure (HV-CT) without nitrogen fertilizer, 20% higher at HV-NT with standard nitrogen fertilizer, respectively than WF-CT. But ear yields of waxy corn were decreased by rye green manure (R-CT) and HV-NT at the condition of no nitrogen fertilizer. It was concluded that hairy vetch was better as winter cover crop to reduce both soil erosion and chemical nitrogen fertilizer simultaneously in slope upland than other cover crops.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.33-41
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• 1986

This experiment was conducted to determine the influence of weed competition in sesame and the periods for weed control. Competition periods (days), for which sesame was seeded under transparent polyethylene film at May 15, were 10, 15, 30, 45, 60, 75, 90, and full growth season of sesame. Weed control periods (days), for which sesame was seeded under black polyethylene film at June 15, were 10, 15, 30, 45, 60, and full growth season of sesame. Dominant weeds were Ponulaca oleracea, Digitaria sanguinalis, Acalypha australis, L. Cyperus arnuricus, Arenaria aesrphllifolia, Cardamine flexucosa, Mollugo Stricta and Digitaria eschaemum. The number of weeds was maximum at the 30 days after planting. Broad leaf weeds were dominant than grass weeds, and then decreased the total number of weeds by the reason of major decrease of broad leaf weeds. However, the weight of weeds increased continuously. No weeds appeared until the 15 days after planting and the weight of broad leaf weeds was heavier than that of grass weeds until 45 days after planting. However, grass weeds were heavier than broad leaf weeds after 60 days after planting. The hazards of weeds on the growth and development appeared seriously from the 60 to 75 days after planting, but main yield reduction appeared from 30 days after planting. Therefore once more hand weeding should be practiced within 30 days after planting to minimize yield decrease. Serious hazards by weed growing appeared by removing black PE film after 15 to 30 days after planting in growth characteristics and 30 days later in grain yield. Leaf growth showed maximum from 45 to 60 days after planting and then decreased as compared with the continuous increase of stem and root in optimum planting, transparent PE film mulch and hand weeding. Leaf growth didn't show reducing in PE film mulch and weedy check but total weight of weeds increased and growth of sesame decreased as compared to PE film mulch and hand weeding. Leaf, stem and root growth of sesame, and weed weight under black PE film mulch showed same tendancy and lower growth of sesame as compared with optimum planting, transparent PE film mulch. Correlation between sesame yield and weeds weight were r =$ -0.874^{**}$ in the optimum planting and r = $-0.712^{**}$ in the late planting, so that the more weeds increase, the lesser sesame yield.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.256-261
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• 2015

Trampling stress in turfgrass fields caused by traffics often occurs in zoysiagrass (Zoysia japonica) fields including golf course. In order to know the influences of trampling stress on the growth and development of turfgrass, leaf and root growth, chlorophyll fluorescence, chlorophyll content and 2-DE protein analysis were conducted in the turfgrass plants subjected to various levels of trampling stress from 0 to $9,420J\;day^{-1}$ day. Shoot growth was more highly inhibited by trampling stress than root growth. Although root growth was affected by trampling with weak intensity, the highest root length was observed in the turfgrass treated with weak trampling ($1,570J\;day^{-1}$). Chlorophyll fluorescence (Fv $Fm^{-1}$) was drastically lowered by trampling stress with moderate intensity. Leaf number showed similar tendency with leaf greenness. The number was decreased as the trampling intensity was increased. Shoot dry weight was decreased showing a similar tendency with the result of shoot length. The specific protein expressions under weak trampling were related to the functions of stress amelioration. Heat shock 70 kDa protein 10 and oxygen-evolving enhancer protein 1 were the proteins increased positively under trampling stress.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.318-322
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• 2014

The effects of cover crops on weed suppression were evaluated in this study. Weed suppressing effects of hairy vetch cover crops were evaluated in summer grain fields. Cover crops were sown at the sowing rate of $60kg\;ha^{-1}$ on Oct. 2012 and Feb. 2013 without basal fertilization. Three weeks old sorghum seedlings were transplanted after minimum tillage on June 2013. Hairy vetch cover crop treatment significantly reduced weed biomass in the transplanted sorghum. By smothering, the cover crops reduced weed biomass to economic level in sorghum. Besides the weed suppression, hairy vetch cover crop resulted in green manure effect on crop growth. Hairy vetch treatment showed beneficial effects on sorghum growth. Reduction of weeds caused by use of strip-tillage machine and polyethylene film mulching was 71% and 88%, respectively. At harvest, yield of sorghum was greater in order of polyethylene film mulching > hairy vetch cover crop > control in transplanted fields.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.212-222
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• 1994

Thiobencarb retarded the growth of new leaves in only barnyardgrass under dry condition while under water condition the shoot growth of broadcast rice, and both shoot and root growth of barnyardgrass was considerably inhibited. Root elongation of rice and barnyardgrass was severely inhibited only under water condition, while that of transplanted rice was slightly inhibited. Inhibition of shoot and root growth in broadcast, drilled rice and barnyardgrass under water condition was much higher than that under dry condition, whereas the inhibition was less in transplanted rice than direct seeded rice. Microscopically, thiobencarb severely inhibited shoot growth and development of barnyardgrass by inducing tubular-like leaves. The cells of the shoot apices of treated barnyardgrass seedling under dry condition was vacuolated and irregularly arranged. Under water condition, leaf primordia of broadcast rice was constricted, barnyardgrass showed tubular-like leaves, inhibited apices elongation and vacuolated cells(visually lack cytoplasm).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.564-570
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• 1997

Field experiments were carried out to investigate the effects of different residue treatment of vetch sward on soil improvement, rice growth and grain yield from 1995 to 1996. With Chinese milkvetch, pH, Ca, and Mg of paddy soil were increased in subsoil(10~20cm soil depth), and organic matter, P$_2$ $O_{5}$, and K were increased in top soil (0~10cm soil depth). Redox potential of the paddy soil with milkvetch residue was severely reduced at earlier flooding period, and recovered gradually as rice growth continued. Weeds were more abundant in the paddy with unchanged vetch stand. The most dominant weed species in the paddy soil with vetch sward residue was Echinochloa crus-galli, followed by Leersia japonica, Polygonum hydropiper in the order of abundance. Seedling establishment ratio of rice directly sown over vetch-sward was lower than in conventional tillage paddy(no-vetch, tilled) condition. Rice growth pattern, however, was not significantly affected by vetch sward treatments. The number of tillers per square meter and plant height at heading date were not significantly different among the vetch-sward treatments. Grain yield was the highest in plough of vetch vegetation, followed by conventional (no-vetch, tilled), live-mulching of vetch, vetch-removed, and vetch-desiccated by weedcide. The whole grain rice yield was the lowest in vetch-desiccated by weedcide.

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.408-412
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• 2013

Dollar spot caused by Sclerotinia homoeocarpa F.T. Benn. is a common and economically important turfgrass disease in South Korea. Fungicides mixture (propiconazole 25% + boscalid 47%) treatments, showing synergistic interaction, with three application rates (low: 50.3 ml $10a^{-1}$ and 97.5 g $10a^{-1}$, intermediate: 67.0 ml $10a^{-1}$ and 130.0 g $10a^{-1}$, and high: 100.5 ml $10a^{-1}$ and 195.0 g $10a^{-1}$) and two application intervals (10 and 15 days) were evaluated for control of dollar spot in creeping bentgrass golf course putting green. In both nontreated plots of field A and B, the disease has severed as 48.3 and 60.0% after the pathogen inoculation. Two fungicide mixture treatments showed significantly higher the disease control effect than a single fungicide treatment (propiconazole). Field A which showed more the disease severity but the fungicide still showed acceptable level of the disease efficacy (89.0%), significant differences in control value were not detected among treatments. The results suggest that the lower application rate of two fungicides mixture treatments may reduce the dollar spot disease severity in creeping bentgrass golf course putting green.

• Weed & Turfgrass Science
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• v.5 no.1
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• pp.42-50
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• 2016

Superintendents have been used microbial fertilizers to improve turfgrass growth and quality and to decrease turfgrass diseases in golf course. This study was conducted to investigate the effects of compound fertilizer containing microbe (MF) on the growth and quality of creeping bentgrass with turf color index (TCI), chlorophyll index (ChI), root length, turfgrass density, clipping yield and nutrient content. Treatments were designed as follows; non-fertilizer (NF), compound fertilizer (21-17-17; CF) as control, compound fertilizer (14-6-17) containing microbe. In pot experiment, TCI and ChI of creeping bentgrass in MF plot were similar to those in CF. But clipping dry weight of MF plot increased by 39.1% compared to that of CF plot. At field experiment applied with MF treatment, TCI, ChI, root length, and nutrient content and uptake of creeping bentgrass were similar to those with CF treatment, but turfgrass density with MF higher about 7.9-15.8% than with CF. These results indicated that the application of MF improved growth and quality of creeping bentgrass by enhancing clipping yield and shoot number.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.7
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• pp.593-598
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• 2006

This study was conducted to investigate the effect of tillage methods such as plowing and rotary tillage (PRT), rotary tillage (RTG), no-tillage after barley straw application (NTB), and barley straw mulching after plowing and rotary tillage (BPR) on the growth and the yield of soybean when cultivated after the cultivation of barley. The methods were compared with the control method in which plowing and rotary tillage after barley straw incineration was applied. Barley straw application resulted in increase in organic matter, total nitrogen, phosphate, and exchangeable cation regardless of tillage methods. Porosity and moisture level in paddy soil was ranked as follows : PRT > RTG > BPR > control > NTB. Decomposition rate of barley straw dramatically increased to 41.7% toward 30 days after soybean sowing, higher in NTB, DRB, and RTG than in BPR. Weed occurrence was decreased 36% in NTB and 40% in BPR. Root activity, nodulation and the dry weight per plant of soybean at flowering stage were highest in NTB and lowest in PRT. Soybean yield in NTB was 3,070 kg/ha increasing 19%, whereas that in PRT was not increased. Therefore in case of a frequent rain during the cultivation of soybean in paddy field PRT could result in excess moisture level in soil, the cultivation without tillage is desirable.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.865-874
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• 2003

Red sorrel, as one of exotic weeds in Korea, was introduced along with imported cereals for concentrate feed or within the seed for forage production. The plant was dominated in grassland and reduced the quality of forage. In particular, this weed cause severe problem in alpine grassland. This study was carried out to investigate the effect and response of red sorrel and forage crops by foliar and soil applied herbicide application. Mecoprop(MCPP) and pendimethaline were selected by pre-field experiment trials and applied to control the red sorrel in grassland. Herbicidal activity of MCPP was 77.2% at 500$m\ell$/10a level and 82.8% at 750$m\ell$/10a level. However, seeds of red sorrel from bare land formed after foliar applied herbicide treatment were germinated and covered bare land. Pendimethalin was not reduced the rhizome growth grown from red sorrel root but retarded seedling growth of germinated red sorrel. The herbicidal activity of pendimethalin to the red sorrel seedling was 83.0%. 2 times application of MCPP at the rate of 750$m\ell$/10a was effective to control of red sorrel regrown from root and herbicidal activity was 93.2%. MCPP and pendimethaline treatment was not reduced growth of grass and have no herbicidal injury to forage crop seedling. Amount of MCPP and pendimethalin remained in grass plant was decreased from 20 days after herbicide treatment and could not be problem in livestock feeding.