• Journal of Nutrition and Health
• /
• 제36권10호
• /
• pp.1030-1035
• /
• 2003

농업생명공학 산업의 발달과 더불어 유전자변형 농산물(GMO)이 개발 및 유통됨에 따라 농약, 노동력의 절감 및 식량난 해결에 도움을 줄 수 있는 반면, 독성, 알러지 유발, 항생제 내성 등 식품으로 섭취될 때 인체에 미치는 영향에 대한 문제가 국제적으로 논의되고 있다. 우리나라 농촌진흥청에서도 여러 유전자 변형 농산물이 개발되고 있으나 일반화에 앞서 그 안전성이 검토되어야 할 것으로 생각된다. 따라서 본 연구팀은 쌀이 우리의 주식인 점을 고려하여 우선 안전성이 검토되어야 할 시험재료로 선정하였고, 영양성분 측면에서의 실질적 동등성과 취약 계층에서의 안전성 검토를 위해 영양성분 분석 후 유전자 변형 쌀을 성장기 흰쥐에게 6주간 급여하였다. 특히 항생제 저항성 유전자마커가 현미에 있을 수 있다는 보고를 고려하여 유전자 변형 품종의 백미밥과 현미밥을 모종인 일품의 백미밥 및 현미밥으로 나누어 처리한 후 실험식이를 급여하였다. 그 결과 시험재료의 영양성분 함량에 큰 차이를 보이지 않았고, 실험식이를 급여하였을 때 모든 실험동물에서 임상적 증상, 조직의 외형이나 무게 및 혈중 영양성분 함량 등의 측면에 차이가 없었다. 그러므로 본 실험에 사용된 유전자 변형 품종(제초제 저항성)은 도정 정도에 상관없이 백미와 현미 모두 6주간 급여시 성장기 실험동물에 어떠한 부정적 영향도 미치지 않은 것으로 보인다. 그러나 유전자 변형 식품의 안전성에 대해 좀 더 보완된 in vivo 실험법의 확립과 1년 이상 장기간의 급여에 따른 영향 검토도 필요하고, 본 연구의 시험재료는 단지 제초제 저항성 품종의 백미와 현미에 대한 것으로 유전자 변형 목적 및 대상 식품의 다양성에 따른 안전성은 다시 검증되어야 할 것으로 생각된다.

• 한국식품영양과학회지
• /
• 제33권5호
• /
• pp.810-814
• /
• 2004

본 연구는 농촌진흥청에서 개발된 유전자 변형 식품의 영양적 안전성을 검토하기 위하여 수행되었다. 발이 우리의 주식인 점을 고려하여 우선 안전성 이 검토되어야 할 시험 재료로 선정하였고, 유전자 변형(제초제 저항성) 쌀의 실질적 동등성 구명을 위해 일반 및 미량 영양소의 함량을 분석하였으며, 대표적 취약 계층인 노령기 모델에서 유전자 변형 쌀을 가지고 안전성을 검토하였다. 특히 항생제 저항성 유전자 마커가 현미 에 있을 수 있고 열처리시 변화될 수 있음을 고려하여 유전자 변형 품종의 현미 및 현미밥과 모종인 일품의 현미 및 현미밥으로 배합한 실험식이를 8주간 급여하였다. 그 결과 시험재료의 영양성분 함량에 큰 차이를 보이지 않았고, 실험식이를 급여하였을 때 모든 실험 동물에서 임상적 증상, 조직의 외형이나 무게 및 혈청 생화학적 지표에 차이가 없었다. 그러므로 본 실험에 사용된 유전자 변형 품종(제초제 저항성 )의 현미와 현미밥 모두 노령기 실험동물에 어떠한 부정적 영향도 미치지 않은 것으로 보인다. 그러나 유전자 변형식품의 안전성에 대해 종 더 보완된 in uiuo 실험법의 확립과 장기간의 급여에 따른 영향검토가 필요하고, 본 연구의 시험재료는 단지 제초제 저항성 품종의 현미에 대한 것으로 다른 유전자 변형 식품의 안전성에 대해서는 계속적인 확인 실험이 있어야 할 것으로 생각된다.

• Journal of Crop Science and Biotechnology
• /
• 제10권2호
• /
• pp.79-85
• /
• 2007

Rice bran application just after transplanting has been increasingly practiced as an herbicide-substitute for organic rice production in Korea. However, this practice is frequently reported to be unsatisfactory in weed suppression. An experiment with five treatments that combines flooding depth, rice bran application dose, and herbicide treatment was done in the paddy field to evaluate whether rice bran application under deep flooding can lead to a successful weed control in compensation for the single practice of rice bran application. Rice bran was broadcasted on the flood water surface just after deep flooding of 8 to 10cm that was started at seven days after transplanting. In the shallow flooding plot without herbicide six weed species were recorded: Monochoria vaginalis, Echinochloa crus-galli, Ludvigia prostrate, Cyperus amuricus, Aneima keisak, and Bidens tripartite. Among the first four dominant weed species, deep flooding significantly suppressed the occurrence of Echinochloa crus-galli and Cyperus amuricus while did not suppress the occurrence of Monochoria vaginalis and Ludwigia prostrate. On the contrary, rice bran application under deep flooding suppressed significantly Monochoria vaginalis and Ludwigia prostrate while didn't exert an additional suppression of Echinochloa crus-galli and Cyperus amuricus compared to deep flooding alone. Rice bran application and deep flooding suppressed complimentarily all the six weed species to a satisfactory extent except for Monochoria vaginalis of which suppression efficacy was 31.9%. Deep flooding reduced the panicle number substantially by inhibiting the tiller production, increased the spikelet number per panicle slightly, and leaded to a lower rice grain yield compared to shallow flooding with herbicide. Rice bran application under deep flooding mitigated the panicle reduction due to deep flooding, increased the spikelets per panicle significantly, and thus produced even higher grain yield in the rice bran application of 2000kg $ha^{-1}$ as compared to the shallow flooding treatment with herbicide. In conclusion, this practice applying rice bran under deep flooding would be promising to be incorporated as an integral practice for an organic rice farming system.

• 한국잡초학회지
• /
• 제15권4호
• /
• pp.247-253
• /
• 1995

The herbicide butachlor [N-(butoxymethyl)-2-chloro-N-(2,6-di-methylphenyl) acetamide] is widely used by farmers as a tool for weed management of transplanted rice(Oryza sativa L.) in Taiwan. The herbicide did not stop germination of rice and weed seeds, but strongly inhibited the subsequent growth of young shoots and roots. The inhibition was also strong on established seedlings. However, they could recover to normal growth after the herbicide effect disappeared. Butachlor greatly decreased the endogenous indole-3-acetic acid (IAA) but increased the endogenous abscisic acid (ABA) contents of rice seedlings. Addition of lAA into growth medium (Hoagland's solution) partly relieved growth inhibition. Pretreatment of both gibberellic acid ($GA_3$) and IAA 24 hours before butachlor treatment almost completely alleviated the butachlor-interfere with GA and/or IAA metabolism or their action resulting in the growth inhibition of rice. Butachlor was readily absorbed by rice roots. During 24 hours of uptake experiment, 32% of the applied herbicide was absorbed. Pretreatment of the herbicide for 2 days did ncx affect the absorption. Of the absorbed herbicide, 80% remained in roots, only 20% transported into shoots, and more than 50% was metabolized to water soluble substances. Thin-layer chromatographic (TLC) analysis indicated that the Rf value of the most abundant metabolite was butachlor-glutathione conjugate. Rice, barnyardgrass (Echinochloa crus-galli (L.) Beauv.), and monochoria (Monochoria vaginalis Presl) seedlings contained relatively high level of non-protein thiols, while the glutathione S-transferase (GST) activity was found highest in rice, barnyardgrass the next, monochoria the lowest. The difference in GST activity among these species might be related to their sensitivity to butachlor.

• Journal of Biosystems Engineering
• /
• 제23권4호
• /
• pp.319-326
• /
• 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.

• 한국잡초학회지
• /
• 제12권3호
• /
• pp.230-260
• /
• 1992

The paper was reviewed the research results on weed dynamics and effective control methods in direct-seeded rice crop. Direct seeding method resulted in drastic increment of weed growth compared to transplanting method and also changed in troublesome weed flora. Two to three fold more weeds were harvested at the direct seeded rice and weed flora of dominant species shifted toward $C_4$type grass weeds. Some of the important troublesome weeds in direct seeded rice were Echinochloa crus-galle, Oryza saliva ssp spontanea, Leptochloa chinensis. Setaria viridus. Digitaria adsendens, Sesbania exaltata, Aeschynomene indica, Algae, etc. Yield loss due to weed competiton was about 40-60% for water-seeded and about 70-100% for dry-seeded rice while these for transplanted rice were about 25-35% for mechanical transplanting and about 10-20% for manual transplanting, respectively. Integrated weed management concept was neede to approach weed control effectively. Several cultural technologies were very effective to suppress the weed growth. These were tillage operation, water management, seeding date and seeding rate. Crop residues of barley, rice, wheat, oat and italian ryegrass were also effectivly suppressed the paddy weeds particularly to Potamogeton distiuctus, a perennial broadleaf weed. A pathogen of Epicoccosorus nematosporus identified from Eleocharis kuroguwai was an excellent potential bioagent to control the most troublesome perennial sedge weed of E. Kuroguwai without arising any detrimental effect. The herbicidal efficacy of this pathogen was as high as bentazon herbicide. Plant growth regulator of paclobutrazol (pp-333) was another possible alternative to reduce the herbicide use. In current, herbicide exhibited the most conspicuous results to control weeds in direct-seeded rice even though the application technologies were not fully established. Recommendations for herbicide application were suggested for in both water-and dry-seeded rice in USA, Japan and Korea, respectively. To make better and comprehensive recommendations further studies on weed ecology and herbicide development were emphasized.

• Journal of Biosystems Engineering
• /
• 제41권4호
• /
• pp.294-303
• /
• 2016

Purpose: This study aimed to evaluate the profitability of four selective mechanization systems in rice cultivation. Methods: Field experiments were conducted in the farmers' field during the wet season (June to November) of 2015 in Bangladesh. Mechanization systems were applied to evaluate four different selective levels (treatment) in eleven consequent operations. Seedlings were raised in a traditional seedbed and trays for manual and mechanical transplanting, respectively. Land preparation, irrigation, fertilizer, pesticide, carrying, and threshing and cleaning operations were performed using the same method in all the experimental plots. The mechanical options in the transplanting, weeding, and harvesting operations were changed. The mechanization systems were $S_1$ = hand transplanting + hand weeding + harvesting by sickle, $S_2$ = mechanical transplanting + Bangladesh Rice Research Institute (BRRI) weeder + reaper, $S_3$ = mechanical transplanting + BRRI power weeder + reaper, and $S_4$ = mechanical transplanting + herbicide + reaper. This experiment was performed in a randomized complete block design with four replications. Power tiller, rice transplanter, BRRI weeder, BRRI power weeder, self-propelled reaper, BRRI open drum thresher, and BRRI winnower were used in the respective operations. Accordingly, the techno-economic performances of the different technologies were calculated and compared with those of the traditional system. Results: The mechanically transplanted plot produced 6-10% more yield than the hand transplanted plot because of the use of tender-aged seedlings. Mechanical transplanting reduced 61% labor and 18% cost compared to manual transplanting. The BRRI weeder, BRRI power weeder, and herbicide application reduced 74, 91, and 98% labor, respectively. The latter also saved 72, 63, and 82% cost, respectively, compared to hand weeding. Herbicide application reduced the substantial amount of labor and cost in the weeding operation. Mechanical harvesting also saved 96% labor and 72% cost compared to the traditional method of harvesting using sickle. Selective mechanization saved 15-17% input cost compared to the traditional method of rice cultivation. Conclusions: Mechanical transplanting with the safe use of herbicide and harvesting by reaper is the most cost- and labor-saving operation. The method might be the recommended set of selective mechanization for enhancing productivity.

• 한국잡초학회지
• /
• 제16권1호
• /
• pp.28-35
• /
• 1996

갈대방제용 선택성 제초제를 스크리닝하기 위한 대조약제로서의 tetrapion의 특성을 온실 및 포장실험을 통하여 조사하였다. 1. Tetrapion을 처리한 식물은 잎이 휘면서 황화되고 생장이 억제되는 증상을 나타내었는데 처리농도가 높을 때에는 식물체 전체가 고사되었다. 2. Tetrapion은 목화를 제외한 모든 작물에 심한 약해를 일으켰으며 벼에 대해서는 직파 벼나 이앙벼의 경우 모두 약해를 일으켰다. 3. Tetrapion의 효과는 광엽 잡초보다 화본과 잡초에 대해 크게 나타났다. 4. Tetrapion은 경엽처리시보다 토양처리시에 더 우수한 효과를 나타내었다. 5. 포장실험시 tetrapion의 갈대방제효과는 처리시기와 포장의 토성에 따라 큰 차이가 있었으며 40kg/ha 이상의 고농도로 tetrapion을 처리하였을 경우에 갈대가 효과적으로 방제되었다. 이러한 결과는 억새의 경우에서도 유사한 경향이었다. 6. Tetrapion은 온실에서 키운 갈대에 대해 토양 및 경엽처리시 모두 우수한 방제효과를 나타내어 갈대방제용 제초제의 스크리닝에 사용할 수 있는 대조약제로서의 가치가 있었다.

• 농업과학연구
• /
• 제40권3호
• /
• pp.183-189
• /
• 2013

This study was conducted to evaluate the efficacy of herbicide mixtures of benzobicyclon and carfentrazone-ethyl in direct-seeding flooded rice. The efficacy of benzobicyclon mixtures and carfentrazone-ethyl mixtures was greater than that of pyrazosolfuron-ethyl + pyriminobac-methyl GR. Herbicide mixtures with benzobicyclon controlled average 97% and herbicide mixtures with carfentrazone-ethyl controlled average 95% 60 days after application. When compared with untreated control, no visual injuries were detected at single and double dosage of herbicide mixtures. The yield of rice increased in both benzobicyclon and carfentrazone-ethyl treatments when compared with pyrazosolfuron-ethyl + pyriminobac-methyl GR. Based on these data, combinations of these herbicides can be applied to provide effective weed management in rice field.

• 한국작물학회지
• /
• 제48권1호
• /
• pp.1-7
• /
• 2003

In spite water direct seeding cultivation of rice has advantages in terms of laborsaving and cost-down, it demonstrates uneven seedling establishment and difficult weed management. To select an applicable mat for mulching system of water seeded rice, weed occurrence, growth and yield performances of rice, and soil temperature were evaluated in several kinds of biodegradable mulching material. Field studies were conducted at the experimental farm of National Crop Experiment Station in 1999 and 2000. Among the mats tested in 1999, Safer-mat had the greatest effect on inhibiting weed occurrence and Lawn-mat demonstrated the least efficacy of weed control (EWC) value. In Safer-mat treatment, Ludwigia prostrata was the dominant weed species but Echinochloa crus-galli was not observed. Different kinds of mulching material from the mats studied in 1999 were tested in 2000. Biodegradable polyester (PES) coated on the recycled paper for newspaper press (RP) treatments showed similar or higher EWC values than non-mulched broadcast seed rice with 2 times of herbicide application (BC-herbicide) and Safer-mat that was the most effective mat on preventing weed appearance in 1999. Immediately after mat mulching on the surface of paddy soil, five pregerminated rice seeds were manually sown in each 3cm-hole formerly punctured at 30${\times}$14 cm spacing in 2000. All the 3 kinds of mulching material tested in 2000 had better seedling stand than BC-herbicide treatment. Rice yield in PES coated with 10 thickness on RP (PES10 $\mu\textrm{m}$＋RP) was a little higher than in BC-herbicide treatment but the former produced less panicles in unit land area than the latter. PES10 $\mu\textrm{m}$＋RP demonstrated a great effect on raising soil surface temperature than non-mulching treatment throughout the period of seedling establishment.