• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1256-1266
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• 2009

Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

• 로봇학회논문지
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• 제11권1호
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• pp.1-8
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• 2016

In this paper, we propose a new algorithm of the guidance line extraction for autonomous agricultural robot based on vision camera in paddy field. It is the important process for guidance line extraction which finds the central point or area of rice row. We are trying to use the central region data of crop that the direction of rice leaves have convergence to central area of rice row in order to improve accuracy of the guidance line. The guidance line is extracted from the intersection points of extended virtual lines using the modified robust regression. The extended virtual lines are represented as the extended line from each segmented straight line created on the edges of the rice plants in the image using the Hough transform. We also have verified an accuracy of the proposed algorithm by experiments in the real wet paddy.

• 한국농공학회지
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• 제17권2호
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• pp.3772-3777
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• 1975

This paper reports on the analysis of the distributions of probable days being good for mechanical rice harvesting and the method of determining the capacity of rice harvesting machinery for the given harvesting duration. In the analysis of the probability distribution of days being good for rice harvesting, the daily rainfalls above which mechanical field work may be impracticable were specified and their frequency of occurances was analyzed by using the weather records during past twenty-one years measured at five different locations. The conclusions being drawn from the analysis are as follows: 1. The distributions of probable workable days in different region and harvesting duration are very distinct and are different to set a uniform trend (refer to Fig. 1-4). 2. The occurance of probable days being good for mechanical field work under 66% confidence level are quite variable by region and by ten-day period. The analysis indicates that the probable workable days may range from 7.5 to 8.5 days of 10-day span within optimum harvesting duration (refer to Table 1). 3. Based on the probability distributions analyzed, the optimun capacities of harvesting machinery required for different harvesting areas and harvesting start-date were estimated as a function of operating duration (refer to Fig. 5 and Table 2)

• Journal of Plant Biotechnology
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• 제38권1호
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• pp.94-104
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• 2011

Salt stress is a major environmental factor influencing plant growth and development. To identify salt tolerance determinants, we systematically screened salt sensitive rice mutants by use of the Activator/Dissociation (Ac/Ds) transposon tagging system. In this study, we focused on the salt sensitive mutant line, designated SSM-1. A gene encoding a NAC transcription factor homologue was disrupted by the insertion of a Ds transposon into SSM-1 line. The OsNAC075 gene (EU541472) has 7 exons and encodes a protein (486-aa) containing the NAC domain in its N-terminal region. Sequence comparison showed that the OsNAC075 protein had a strikingly conserved region at the N-terminus, which is considered as the characteristic of the NAC protein family. OsNAC075 protein was orthologous to Arabidopsis thaliana ANAC075. Phylogenetic analysis confirmed OsNAC075 belonged to the OsNAC3 subfamily, which plays an important role in response to stress stimuli. RT-PCR analysis showed that the expression of OsNAC075 gene was rapidly and strongly induced by stresses such as NaCl, ABA and low temperature ($4^{\circ}C$). Our data suggest that OsNAC075 holds promising utility in improving salt tolerance in rice.

• 한국농공학회지
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• 제35권2호
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• pp.73-80
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• 1993

A simplified physiologically-based dynamic model, SIMRIW was selected for predicting the growth and yield of rice. The applicability of the model to the rice cultivars and weather conditions in the Republic of Korea was evaluated. Parameters of the model were calibrated using actual rice yields in Suweon region and an optimization scheme, Constrained Rosenbrock Algorithm. The simulated results from the calibrated model were in good agreement with the field data. The model with parameters calibrated for Suweon was applied to other five regions for the evaluation of transferability, but the simulated results fell short of satisfaction. However, the model is found to be applied to real-time prediction of the growth and yield of rice crop, which is believed to be useful for timely rice crop management, agricultural policy making, and optimal irrigation water management.

• 농업과학연구
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• 제48권1호
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• pp.59-71
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• 2021

This study investigated the extent to which rice producers from the Ayeyarwaddy Region of Myanmar could improve their productivity if inputs were used efficiently in rice cultivation. To achieve this objective, simple random sampling was used to collect data from 300 rice growers in the study area. Data were analyzed with the translog stochastic frontier approach to understand the production efficiencies. The study further estimated the influencing factors that affect the efficiency levels of rice farmers. The empirical result reveals that the average technical, allocative, and economic efficiencies were at 76.11, 47.85, and 34.15%, respectively. This suggests that there is considerable room for improving rice production by better utilization of the available resources at the current level of technology. This study suggests that strenthening agricultural training programs and adoption of improved rice varieties may reduce overall inefficiencies among rice farmers in Myanmar. Factors like age, household size, education, farming experience, farm size, rice variety, training, and off-farm income have a significant impact on increasing/decreasing farmer's efficiency. Efficiency can be improved by establishing farmer field school programs to increase the scale of operations. The government should encourage young educated people to participate in paddy production and also intervene to reduce input prices and control the quality of seeds.

• 한국작물학회지
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• 제68권2호
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• pp.35-46
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• 2023

The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15^th for early and mid-maturing rice and July 5^th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30^th.

• 한국작물학회지
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• 제50권spc1호
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• pp.94-98
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• 2005

경북 지역 농업기후 지대를 미질 및 식미치를 근거로 하여 다시 세분화된 지대를 설정하고자 2002년부터 2004년까지 3년간 경북 전 지역에서 가장 많이 재배되고 있는 품종 중 중만생종인 일품벼, 주남벼, 남평벼, 중생종인 화영벼, 조생종인 오대벼를 재배하고 있는 논 513개소의 쌀을 수집하여 분석 조사한 결과를 요약하면 다음과 같다. 1. 지대별 식미치의 평균은 동해안 남부지대가 67.6로 다른 지대에 비해 약간 낮았으며, 완전미 비율은 동해안 남부지대 및 동해안 중부지대가 각각 $87.3\%,\;88.2\%$로 낮았으며 변이계수도 각각 $8.2\~8.3\%$로 높았다. 단백질 함량은 동해안 중부지대가 $8.0\%$로 다른 지대에 비해 약간 높았고, 변이계수도 $8.8\%$ 높았다. 2. 특정지역을 세분하여 쌀 품질을 조사해보면 전체 평균의 변이계수보다 높게 나타나는 지역과 낮게 나타나는 지역으로 뚜렷하게 구분된다. 변이 계수가 크다는 것은 특정 지역 내에서도 쌀 품질의 세분화된 지역간 차이가 심하므로 고품질 쌀 생산을 위해서는 세분화된 벼 재배 구역 설정하여 적지적작의 정밀농업이 필요하였다. 3. 식미치를 근거로 세분화된 지대의 쌀 품질 요인에 대한 연차 간 변이계수는 기존 농업기후지대의 변이계수보다 상당히 낮아져, 세분화된 지대별 고품질 쌀 생산을 위한 특정 지역의 정밀 기술 개발 및 보급의 기초 자료로 활용할 수 있을 것으로 사료되었다.

• 한국응용곤충학회지
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• 제4권
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• pp.1-6
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• 1965

In Korea the most important plant industry is the rice-growing but she has not yet attained self-sufficiency with regard to rice which is the basic food of Korean. In the past, various measures of increasing rice production have been tried with some success but the increasing rate of did not show the sufficient result. Judging from experiences, disease control may be the most important factor which has influence on increasing of rice production in Korea. During the past 60 years three periods divided by the transition of rice diseases were noted, and especially the recent transition attracted much attention . That is, sheath blight and stripe which were minor diseases in the past have promptly spread all over the country and caused heavy losses to rice plant, and also local outbreak of bacterial leaf blight and dwarf were noticed. Various environmental factors are related to such transition of rice disease. Above all, cultivated varieties susceptible to these diseases, increase of application of nitrogenous fertilizer, earlier transplanting and density of transplanting are considered to be lucre closely related to the development of these diseases and successive development of blast. On the other hand. application of forage fungicides such as organic mercury compounds specific to blast contributed to reduce prevalent area if blast in spite of wide spread of susceptible varieties and increase of application of nitrogenous fertilizer. These facts were confirmed by Korean investigators At the present which various diseases to control coexist in the same region, no one variety resistant to all of these diseases is provided and cultural practices for the control of these diseases often do not produce sufficient yield of rice. it is emphasized that a role of pesticides is very great.

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1322-1330
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• 2010

Three types of nuruk were made from rice, wheat, and a rice-glasswort (6:4) mixture. Nuruk, makgeolli, and vinegar were manufactured with rice nuruk (RN), wheat nuruk (WN), and rice-glasswort nuruk (RGN). The variable region of 18S or 16S rDNA amplified with genomic DNA extracted directly from nuruk-, makgeolli-, and vinegar-making cultures was analyzed via temperature gradient gel electrophoresis (TGGE). The sequence of the 18S rDNA variable region extracted from the TGGE gel for nuruk was 99% homologous with Aspergillus sp. and that for the makgeolli-making culture was 99% homologous with Saccharomyces sp. and Saccharomycodes sp. The sequence of the 16S rDNA variable region extracted from TGGE gel for the vinegar-making culture was 98% homologous, primarily with the Acetobacter sp. The eukaryotic and prokaryotic diversities in the nuruk-, makgeolli-, and vinegar-making cultures was not significantly altered by the addition of glasswort. Prokaryotic diversity was higher than eukaryotic diversity in the nuruk, but eukaryotic diversity was higher than prokaryotic diversity in the makgeolli-making culture, on the basis of the TGGE patterns. No 18S rDNA was amplified from the DNA extracted from the vinegar-making culture. The diversity of the microbial community in the process from nuruk to vinegar was slightly affected by the type of raw material utilized for nuruk-making. The saccharifying activity and ethanol productivity of nuruk, polyphenol content in makgeolli, and acetic acid and polyphenol content in the vinegar were increased as a result of the addition of glasswort. In conclusion, the glasswort may be not simply an activator for the growth of microorganisms during the fermentation of nuruk, makgeolli, or vinegar, but also a nutritional supplement that improves the quality of vinegar.