• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.337-342
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• 2012

This study was conducted to evaluate the weed suppressing effects of different cropping system including hairy vetch and rye cover crops, polyethylene plastic film, and transplanting film mulching in direct sowing and transplanted foxtail millet field in 2011. Crop growth and development and weed occurrences in the fields were examined to know the efficiency of proposed cropping system. In polyethylene film mulching treatment, heading date of foxtail millet was earlier by 4 days than control, on the other hands, rye cover crop mulching delayed heading date by 8 days. Besides the effect of cover crop on the heading of foxtail millet, the residues changed growth characteristics. Plant height of foxtail millet was increased by 92.4% at hairy vetch treatment although the height of was reduced by 63.7% in the rye cover crop treatment. Hairy vetch treatment showed beneficial effects on foxtail millet growth reduced the occurrences of grasses and broadleaf weeds higher than 90%, as compared to control in foxtail millet fields. While rye cover crop treatment showed poor foxtail millet growth reduced less strongly grasses and broad-leaf weeds by 47% and 90%, respectively. At harvest, yield of foxtail millet was greater in order of hairy vetch cover crop > polyethylene film mulching > rye cover crop ${\fallingdotseq}$ control in both transplanted and direct sown fields.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.187-192
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• 1994

This study was conducted to evaluate the effect of herbIcides on weed control, growth characteristics and yield in Angelica gigas NAKAI, after transplanting it to the field. All herbicids treated had no effect on the emergency period, bolting rate, and growth characteristics of A. gigos. Simazin wp, methabenzthiazuron wp were slightly harmful, but linuron wp pendimethalin ec, triflurain ec had no injury on the A. gigas, even with double dosage level. Under the treatment of pendimethalin ec, linulon wp, effect of weed control valuae at 55 days after transplanting was 89.6, and 88.3 respectively with 5 or 7 species of weeds appearing. Broadleaf weeds f?ere abundant than grasses, and the major weeds were C. albam, C. flexuos, D.sanguinalis, and E. arvense. Dry yield were increased somewhat more with herbicides than by hand weeding, even with double dosage level.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.62-70
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• 1994

This study was conducted to find out if there are some differences in germination, growth and morphological characteristics between rice(Oryza saliva) and barnyardgrass(Echinochloa crus-galli) under various cropping patterns and to abtain the fundamental information on weed control method in direct seeded rice. Rice was broadcast on soil-surface(Broadcast rice), drill seeded in soil(Drilled rice) and barnyardgrass was drill seeded in soil(Barnyardgrass) under dry(Dry condition) and water direct seeded condition(Water condition). Also rice was transplanted with 8-day seedlings(8 -day-old seedling) and 25-day seedlings(25-*day-old seedling) under transplanting condition(Transplanting condition) At 1, 2, 3, 5, 7, 10, 15 and 20 days after seeding or transplanting(DAS/T), plants were harvested to examine their germination, growth and morphology. The major results were as follows ; Until 5 DAS/T growth of rice and barnyardgrass were well established under dry condition but under water condition growth of shoots was mainly elongated. At 20 DAS/T barnyardgrass had greater plant height and shoot fresh weight than rice under direct seeded condition, while plant height and shoot fresh weight of rice was greater than those of barnyardgrass under transplanting condition. Root length of barnyardgrass was greater under the dry, drilled, direct seeded conditions than that of rice under the water, broadcast, transplanting condition, respectively. And root fresh weight of rice under direct seeded condition was similar to that of barnyardgrass but that of rice under transplanting condition was significantly greater than that of barnyardgrass. Barnyardgrass only formed mesocotyls and its length increased with increased depth of seeding. Leaf stage and leaf area of barnyardgrass was greater under the dry, drilled than those of rice under water, broadcast conditions, respectively, while those of rice was greater than those of barnyardgrass under transplanting condition. Chlorophyll contents were higher in barnyardgrass, dry direct seeded rice, transplanted rice, water direct seeded rice in descending order.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.127-132
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• 2012

Field survey on the weed occurrence and the use of herbicides was carried out targeting 214 rice cultivating farmers at Gyeongsangbuk-do. 96.2% of farmers did machine planting in late May and this is 68.0% of total cultivating area. Spring plowing was first with 54.6%, followed by spring-fall and fall plowing with 24.8% and 15.0%, respectively. 75% of the farmers treated herbicide twice. 57.5% of them treated herbicide before transplanting and treated at post-emergence again. In case of only application, 84% of the farmers treated herbicide before transplanting. Twenty-three species were occurred at Gyeongsangbuk-do and Echinochloa spp. was the most dominant with 20.8%, Sagittaria trifolia was second with 10.4%, followed by Monochoria vaginalis and Sagittaria pygmaea with 9.9% and 9.7%, respectively. Sagittaria pygmaea was the most difficult to control followed by Echinochloa spp., M. vaginalis, and S. trifolia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.439-451
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• 1982

In fact, rice cultivation technique from 1962 to 1970 was very slight, but this technique from 1970 to now was remarkably developed in Korea, it was due to development of high fretilizer responsive and lodging resistant variety, Tongil; ie. Ind. ${\times}$ Japonica remote-cross rice variety. The main factors of this development is as follow: Firstly the most farmer (more than 90%) used newly developed seedling growth method; polyethylene film covered protected nursery bed. Secondly date of transplanting (middle or late part. of May) was earlier 10-15days than before 1970. Thirdly new varieties were highly lodging resistant at high fertilizer level $(N-P_2O_5-K_2O:15-9-11 kg/l0a)$. However, this level is 50% increased one than it for Japonica varieties. At forth planting density increased up to 75-80 hills per $3.3m^2$. Added to these factors, farm labor shortage and wage increase due to economic development gave a chance for introduction of transplanting machine to farmer in 1977. It's use increased for 100, 800 ha in 1981. The most of farmers are using herbicides and weed control system dependoing on wood composition has been established and disseminated to farmer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.104-115
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• 1992

The rice culture techniques included 'Jodosukyungbeob'(旱稻水耕法 : culture techniques of early-ripening paddy rice), 'Mandosukyungbeob' (晩稻水耕法) : culture techniques of late-Ripening paddy rice 'Handobeob'(旱稻＆lt;山稻＆gt;法 : culture techniques of upland rice), 'Myojongbeob'(苗種法 : culture techniques of paddy rice by transplanting), 'Kunangbeob'(乾秧法 : culture techniques of rice by transplanting which rears seeding in dry paddy) and 'Sudogunpanongbeob'(水稻乾播農法 : culture techniques of paddy rice seeding in dry field). Especially, 'Kunangbeob' and 'Sudogunpanongbeob' were originally developed in Korea as seen in 1600s(Kyoungje : 經濟) and early 1800s (Yoji : 要旨). In 'Jodosukyungbeob' it took 9 days for seed dipping, water-sprouting and prevent damage by birds, each for 3 days in China, but in Korea seed dipping in water took 3 days and the rest of the procedures were flexibly established. In matured soils, practices were fall plowing right after harvest, recognition of effective tillering and additional fertilization use of human manure, and stimulation of sprouting by lime application. The unique culture techniques adequate for Korean situations were practiced, which included weed control after draining accurately for 3 to 4 times, draining at mid season for improving wind and drought tolerance, rice harvesting at appropriate time for preventing grain shattering, and seeding in rows. 'Mandosukyungbeob' was improved techniques contrast to those of China, and the major contents were selection of proper varieties, good stand establishment by seeding high rates, induction of vigorous tillers, and adoption of 'Jokjongbeob'(足種法 : seeding method by foot). Also, one of the most prominent rice cultures by our ancestors was 'Kunpanongbeob' that was systemized form habitual practice of Pyongan Province. The unique technique actualized was 'Hando [旱稻(山稻)]' culture technique which was the combinations of 'Jokjongbeob', root stimulation method, and disaster-tolerant mixture cropping with adoptation of variety theory, although it was originated from China. The transplanting techniques has come before 'Jikseol'($\ulcorner$直說$\lrcorner$) and its merits were sufficiently realized. However, this method was basically prohibited from the early Chosun dynasty because extremely bad harvest was expected under drought conditions and insufficient conditions of water storage. But, it was permitted in the areas that contained water all the times and in case of large-scale farming especially. Most of rice culture was transplanted in the end of the Chosun dynasty because transplanting was continuously spreaded in the three southern provinces of Korea. Under these circumstances, transplanting technique was improved from the early to the end of the Chosun dynasty by weed control, fertilizing, water management, and quadratic transplanting. Based on these techniques, agricultural productivity was improved 5 times by that time. 'Kunpanongbeob' was created and developed properly for Korean conditions that is dry in early season and flooding in late season. This was successively developed and established into transplanting technique of nursery seedling.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.223-229
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• 1992

Very recently, the cultural pattern of paddy rice in Korea was transitted in a short period, and resulted as earlier in season and more in fertillizer application among others. Specially the weed emergence in paddy fields was drastically increased as affected by change of cultural pattern into early planting and into direct seeding methods. Of course, the direct-seeding in row seeding induced more weeds than in broad-cast direct -seeding. By maintaining the water level with saturation of the paddy surface induced more weeds, relatively more annual weeds than by deep in water level, respectively. Relatively more annuals in number of species and in emerged quantity comparing with perennials was caused by the shifting of cultural methods from transplanting to direct seeding. The severe weed competition damages were mainly resulted due to the shading by taller plant heights of weeds than crop during the whole growing seasons. Conclusively, accepting of direct seeding methods in paddy rice culture in Korea, the present bases for weed control methods ought to be naturally and effectively improved to meet the newly made weed problems.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.176-180
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• 1996

In order to estabilish a labour-saved and environmental protected paddy rice system in Southern Korea, new system, called no-tillage paddy system, was proposed and investigated from 1988 to 1996. Under the no-tillage paddy system, occurrence pattern, control value and regrowth of water foxtail each treatment(herbicides and application dates), and occurrence of volunteer rice plant in application dates of herbicide were investigated. The growth of water-foxtil was markedly increased from middle of May and no. of tillers and dry weight of water-foxtail increased up to 3rd crop year in no-tillage. Glyphosate application for control of water-foxtail was 20 days before transplanting. And when the soil under the no-tillage paddy system in May 1 and May 10 application of herbicide machine-transplanted with 8-day-old seedlings missing hills were increased compared to April 20 and early growth stages of machine transplanted of rice in April 20 applications of herbicide showed increased plant height, no. of tillers of rice, occurrence of volunteer rice plants from the shattered seeds were 1,600plants/10a and decreased in May 10 compared to April 20 and May 1.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.266-271
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• 2010

This study was conducted to improve weeding effect by rice bran farming technique. In the weeding effect experiment by application timing control of rice bran and soybean cake, weeding efficacy was the highest at the treatment of conventional application of rice bran. The treatment of soybean cake with rice bran was unfavorable, but Echinochloa crus-galli occurred little at the treatment of soybean cake at 5 days after transplanting, so it is thought that further study about inhibitor of early E. crus-galli occurrence in soybean cake is necessary. Cultivating weeder was effective at the treatments of rice bran and soybean cake together, of which weed occurrence was more than conventional rice bran, and precise experiments about cultivating weeding time and method will be necessary.

• Korean Journal of Weed Science
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• v.11 no.3
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• pp.174-177
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• 1991

This study was conducted to determine the influence of dithiopyr on growth of transplanted rice with different transplanting depths and the amount of $^{14}C$-dithiopyr adsorpted in the root and shoot of rice plants under paddy soil conditions. The growth rate of transplanted rice was lower in 0 and 0.25cm of transplanting depths with exposed basal stem than in 1 and 2cm of the depths in control plot. In the growth of transplanted rice treated with dithiopyr, plant hight and dry weight were significantly inhibited in 0 and 0.25cm depth plots but not affected.in 0.5, 1, 2 and 4cm depth plots, and roop length were influenced in 0, 0.25 and 4cm depth plots but not in 0.5, 1 and 2cm depth plots. The amount of ratioactivity in shoot and root of rice plants as affected by $^{14}C$-dithiopyr were the highest in 0 and 0.25cm depth plots and decreased in over 0.5cm depth plots. However the extent in amount of distributed radioactivity in the plants among the different transplanting depths was narrow gradually with the growth of plants. Therefore, injury of transplanted rice by dithiopyr is little in over 0.5cm transplanting depth with burried basal stem and the inhibition on rice plants with extreme shallow transplanting such as 0 and 0.25cm depths should be due to more adsorption of dithiopyr.