• Korean Journal of Weed Science
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• v.4 no.1
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• pp.11-18
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• 1984

The effect of transplanting method of rice seedlings on weed occurrence was investigated at the Yeongnam Crop Experiment Station in 1983. Rice was transplanted by hand and machine and eleven common herbicides were applied. The greatest weeds were harvested from the plot that rice was not transplanted and more weeds encountered at machine transplanted plot than hand transplanted plot. The degree of weed suppression by rice plant itself was 50% for machine transplatning and 55% for hand transplanting, respectively. Simpson index and community dominance of weed species were the highest in hand transplanting and followed by machine transplanting and no rice plot in order. Rice grain yield was exponentially correlated with the amounts of weed occurrence and more yield loss exhibited at machine transplanting than hand transplanting in the same amount of weeds. In the herbicidal activity, most of herbicides performed better at hand transplanting than machine transplanting while the degree of difference between transplanting methods varied depend on herbicide used.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.246-251
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• 1983

In recent years weed flora have been changed to perennial dominance in paddy field being affected by the cropping systems and cultural practices. The perennial weeds are difficult to be controlled with annual herbicides which occupy 94% of total consumption of herbicides. The weeds competed more with rice plants in early tillering stages in machine transplanted field. For the reasonable and effective weed control, it is advisable to use single ai herbicides in hand transplanting field, but combined and mixed herbicides should be applied in machine transplanting field.

• Plant Resources
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• v.5 no.3
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• pp.187-191
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• 2002

This experiment was conducted to investigate the effects of turf grass growth to seedling rates and bed soil types. The results of this experiment were summarized as follows; the more increasing the seedling rates, the plant height and leaf length were longer, but the number of leaf and number of branch were fewer. Incase of transplanting of turf grass seedling by rice transplanting machine, it might be considered that the proper alternative bed soil was sandy loam soil with regarding to the economic aspects. The maximum seedling rate of turf grass in the seedling tray for rice was 1,000 of seedling amount due to the nutrient competition with intensive seedling. As the results indicated, it might be recommended that the proper alternative bed soil was sandy loam soil with 1,000 of seedling rates in case of transplanting of turf grass seedling by rice transplanting machine.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11a
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• pp.31-36
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• 2002

This experiment was conducted to investigate the effects of turf grass growth to seedling rates and bed soil types. The results of this experiment were summarized as follows; the more increasing the seedling rates, the plant height and leaf length were longer, but the number of leaf and number of branch were fewer. In case of transplanting of turf grass seedling by rice transplanting machine, it might be considered that the proper alternative bed soil was sandy loam soil with regarding to the economic aspects. The maximum seedling rate of turf grass in the seedling tray for rice was 1,000 of seedling amount due to the nutrient competition with intensive seedling. As the results indicated, it might be recommended that the proper alternative bed soil was sandy loam soil with 1,000 of seedling rates in case of transplanting of turf grass seedling by rice transplanting machine.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.141-144
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• 1997

Studies were conducted to investigate the incidense of insect pests in transplanted and direct seeded paddy fields in southern region of Korea. Population dencities of the rice green leafhopper (RGLH: Nephotettix cincticeps Uhler) and rice leaffolder (RLF: Cnaphalocroch medinalh Guenee) were higher in machine transplanted than in direct seeded, but the brown planthopper (BPH: Nilaparvata lugens Stal) and smaller brown planthopper (SBPH: Laodelphax striatellus Fallen) were abundant in direct seeded. However, no significant difference was found between machine transplanted and direct seeded fields in the incidense of rice stem borer (RSB: Chilo suppressalis Walker), whiteback planthopper (WBPH: Sogatella furcifera Horvath), and rice stem magot (RSM: C'hlorops oryzae Matsumura). Occurrence of rice key pests were affected more by transplanting time than other cultural practices. Later transplanting induced higher populations of BPH, WBPH, SBPH, RGLH. However, RSB and RLF caused higher damage in earlier transplanted paddy field.

• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.2
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• pp.77-86
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• 2019

To determine none top soil covering in rice seedling nursery method for the sparse machine transplanting, four different sowing methods were tested. Shoot and root length, fresh weight, leaf number and color using leaf color chart(LCC) and SPAD were collected as the data comparison of methods. The seedling height showed the highest growth according to the conventional (230g seed rate of pre-emerged seeds and top-soil covering) > high sowing density 1 (290g seed rate of pre-emerged seeds and top-soil covering) ≥ high sowing density 2(290g seed rate of pre-emerged seeds and none top-soil covering) > high sowing density 3(290g seed rate of iron-coated seeds and none top-soil covering). There was any statistical difference between groups in root length, leaf number, LCC, and SPAD values. Thus, a high sowing density of 290g for rice nursery seedling box was recommended to the sparse machine transplanting in rice cultivation with the none top-soil covering method, enabling convenient handling in transportation and machine transplanting work.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.114-121
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• 1993

Differences in need occurrence and competition were investigated among five types of rice(Oryza sativa L.) cultivation. Dry weights of weeds in between transplanting and/or seeding and heading date showed in the decreasing order of dry direct-seeded, flood direct-seeded, machine transplanting with 10-day-old seedling, machine transplanting with 30-day-old seedling, and conventional hand transplanting. A similar trend was obtained with application of weedy followed by weed-free. Weed-free periods allowed to decrease by 20% dry weight of rice were 3 weeks after transplanting(WAT) in transplanting cultivations, 5 weeks after seeding(WAS) in wet direct-seeded rice, and 7-8 WAS in dry direct-seeded rice. On the other hand, weedy periods as determined by the same criterion were 9 WAT in conventional hand transplanting and machine transplanting with 30-day-old seedling, 7 WAT in machine transplanting with 10-day-old seedling, 8 WAS in dry direct-seeded rice, and 6 WAS in flood direct-seeded rice.

• Journal of Biosystems Engineering
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• v.23 no.4
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• pp.319-326
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• 1998

A herbicide applicator attached to a rice transplanter was developed to perform herbicide application and transplanting simultaneously. The prototype machine was composed of herbicide tank, discharge device, spinner, scattering plate and power drive. The application rate of the machine could be adjusted from 10 to 30 kg/㏊ and the application swath was 1.8m. According to the field test, application uniformity showed the range of 13.6~43.9％ in terms of CV(coefficient of variation) depending on the spinner speed, application height and shape of diffuser. The best uniformity could be achieved with the spinner speed of 30.8m/s and application height of 20cm. Field efficiency of the prototype was 4.7hr/㏊. Transplanting machine has field efficiency of 4.6hr/㏊ in Korea. By attaching the herbicide applicator, field efficiency became lowed only by 0.1hr/㏊, which was counted for filling time of herbicide. Simultaneous operation of transplanting and herbicide application had a of labor saying. The weed control efficacy was measured to be 96% in field when AC140 + Stomp and Londax + YRC was applied at the 65th day after transplanting. Nonanmae was treated by manual application to be compared to.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.232-236
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• 2000

To obtain a basic information on the development of effective control strategies for weedy rice in direct seeding rice cultivation, occurrence patterns of weedy rice as influenced by different cultural practices such as cultivation method, water management, seeding time, and tillage were investigated in field or pot experiments. High occurrence of weedy rice was observed in a continuous direct seeding paddy field as compared to machine transplanted one. Based on the percent of weedy rice panicle over three years trial, high ridged dry seeding was highest with 36.9%, followed by wet seeding with 30.9%, water seeding with 14.6% and machine transplanting rice with 0.8%, indicating 97.8% reduction in weedy rice occurrence by machine transplanting rice as compared with high ridged dry seeding. Germination of weedy rice was promoted to 83-94 % when rice panicle was flooded from September 30 to October 10 for 6 days and 74-88% for 9 days on October 20. Weedy rice occurrence was also substantially reduced by delayed seeding on June 10 and intensive tillage. The results suggest that machine transplanting rice be more effective cultural practice than flooding treatment, delayed seeding and intensive tillage when weedy rice problem occurs in direct seeded paddy field.

• Plant Disease and Agriculture
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• v.1 no.1
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• pp.14-18
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• 1995

This study was carried out to investigate effect of transplanting method, environmental factor, and fertilizing level on occurrence of Pseudomonas glumae in south-west coastal area of Chonnam province. Occurrence in filed began after heading and increased gradually during 3-4 weeks. Occurrence of this disease was great at daily minimum temperature of 23-$25^{\circ}C$ and series of rainfall during early and mid. August Degree of infection by fertilization of nitrogen and by transplanting fertilizing level of 50% than standard fertilization of nitrogen and by transplanting method was greater machine-transplanting than hand-transplanting. Rate of degradation was 6.5% in case of 10% of infected panicle, 14.5% in 30%, 22% in 50% and 35.9% in 70%. We can reduce occurrence of this disease by sawing non -infected seed and balanced fertilizing in cultural practice and applying oryza 4kg/a in early transplanting or Kasugamin EC and Allta in heading stage.