• 한국농공학회논문집
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• 제52권1호
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• pp.33-40
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• 2010

The cemented sand and gravel (CSG) method is a construction technique that adds cement and water to rock-like materials, such as rivered gravel or excavation muck which that can be obtained easily at areas adjacent to dam sites. This study was performed to evaluate the planting properties of herbaceous plant and cool-season grass in CSG blocks that were manufactured by using CSG materials to develop environmentally friendly CSG method. The two types of CSG-0 without cement and CSG-100 with $100\;kg/m^3$ of cement were designed to evaluate compaction, unconfined compressive strength and growth of plants with cement content by using modified E compaction. To analyze growth properties of plants, germination ratio, visual cover, plant height and root length were measured in 4 weeks and 8 weeks after sowing. As the results, the germination regardless kinds of plants started within 5~7days and the germination ratio were in the range of 50~60 %. The visual cover of kinds of plants by visual rating system were in the range of 7~8 and the visual cover of tall fescue and perennial ryegrass was higher than that of lespedeza cuneata. The plant height and root length for tall fescue and perennial ryegrass in 8 weeks after sowing were in the range of 22~26 cm, 12~15 cm and 4~6 cm, 3~5 cm, respectively.

• 상하수도학회지
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• 제9권2호
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• pp.97-107
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• 1995

Today a conventional water treatment system has many problems. The ozone/GAC process, sometimes termed Biological Activated Carbon(BAC), appeared to be effective for the removal of soluble organic matters in the drinking water. The water quality of Nak-dong river in Pusan, generally shows BDOC 30-40% and NBDOC 60-70%. The pilot plant installed at the Duk-san water works that was been largest treatability(1,650,000ton/day) in Pusan. A experimental water in the pilot plant made use of the water after sand-filteration. Following results are drawn from this study. Initial adsorption velocity($DOC/DOC_o/T$) in the pure adsorption of GAG had a 0.0225, it's velocity changed to 0.006 after ozone added and the optimum ozone dose ranged of $1.4-2.0mgO_3/L$. A experimental water in the pilot plant composed with humic material(78%). Humic material composed with humic acid(20%) and fulvic acid(56%), and it's rate changed to 18 and 50% respectively after ozone added. DOC constantly decreased in the EBCTs and removal efficieny in the 15min of EBCT was 45-50%. It showed the largest removal rate of BDOC in the EBCT 5 and among the season, characteristics of removal varied. The HPC distributed over $10^6-10^7CFU/cm^3$ in the bed depth and among the season, distribution of HPC were differential.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.439-448
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• 2011

Oxalic acid is synthesized by a wide range of plants. A few of them are forage plants that can cause oxalate poisoning in ruminants under certain conditions. In this paper, the role of some agronomic, climatic and genetic factors in minimizing oxalate accumulation in forage plants has been discussed. Research indicates that the content of oxalate in forage can be controlled by fertilizer application. For example, nitrate application resulted in higher contents of soluble and insoluble oxalates than ammonium application. With an increased rate of potassium application, soluble oxalate content showed an increasing trend and insoluble oxalate content showed a decreasing trend. With an increased rate of calcium application, soluble oxalate content showed a decreasing trend and insoluble oxalate content showed a reverse trend. Other agronomic factors such as growing season, harvesting practices, plant maturity, plant species, plant variety and plant parts can also have a large effect on oxalate accumulation. However, the potential benefits of the above approaches for improving forage quality have not been fully exploited. In addition, there is still insufficient information to fully utilize means (e.g. plant nutrients, season and soil moisture) to minimize oxalate accumulation in forage plants. Therefore, more research is required for a better understanding of the interactions between oxalate and the above-mentioned factors in forage plants.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2000년도 추계 학술발표회
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• pp.18.1-18
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• 2000

• Animal cells and systems
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• 제2권1호
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• pp.55-63
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• 1998

The effects of inflorescence herbivory and flowering time on plant architecture and reproductive yields were examined with a perennial herbacious species, Vicia cracca, occurring in Natick, Massachusetts, USA. Natural herbivory on inflorescences was observed among the total of 157 plants during a growing season. Vegetative and reproductive characters were measured in the field as well as in the lab depending on the characters. Approximately 64% of the plants were subjected to herbivory on inflorescences. Plants were classified into three groups; unbrowsed plants, partially browsed, and totally browsed plants, according to the level of herbivory on inflorescences of each plant. Plants were also categorized by their flowering time such as early vs late flowering plants. Herbivores tended to favor inflorescences on rather small plants, resulting in a pattern of totally contact or partially intact inflorescences on taller plants. The mean number of stems, which was assumed to be a direct result of severe herbivory in this population, differed among herbivory groups. There also was a tendency that plants flowering late in the season had more nodes with more leaves, suggesting that herbivory on stem tips early in the season before flowering might have induced growth of side branches or branchlets along the main stems. Comparison between unbrowsed and partially browsed plants showed that the latter compensated for browsing in terms of numbers of inflorescences, fruits, seeds and seed size (weight), though they did not compensate in flower number. The probability of fruit production (presence vs absence of fruits) and seed weight declined toward the end of the season. These results suggest that resources are deficient at the end of the season. Almost complete reproductive failure in totally browsed plants is attributed to the destruction of inflorescence display and the disadvantage of small vegetative size of those plants. After all, in this population, a moderate level of herbivory on inflorescences did not reduce the maternal fitness of the plants. However, severe herbivory on inflorescences resulted in antagonistic interactions between plants and herbivores.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.57-61
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• 2009

Three years($2004{\sim}2007$) survey was conducted on the incidence of silkworm diseases namely, Grasserie, Flacherie, Muscardine and Uzi fly, a silkworm pest with 150 sericulture farmers in the districts of Chittoor and Anantapur in Andhra Pradesh. The data revealed that grasserie and flacherie incidence were maximum in summer season and minimum in winter season whereas muscardine was observed high in winter season in both the areas and rarely in rainy season in Chittoor and Anantapur districts. An improvement of 11.16 and 7.6 kg cocoons/100 dfls were recorded in the batches of PM xCSR2 Diseases free layings(Dfls) reared in rearing houses disinfected with 2% bleaching powder and Ankush, a plant based bed disinfectant applied as per schedule, respectively. The Uzi fly incidence was suppressed by 61.02% in batches where the integrated package was adopted for control of Uzi fly infestation.

• The Plant Pathology Journal
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• 제22권1호
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• pp.1-6
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• 2006

The population shifts of Monilinia fructicola isolates which were resistant to the fungicide benzimidazoles were investigated in four regions of Korea from 1998 to 2000. The isolation frequency of benzimidazole-resistant isolates ranged from 18.8% to 29.6% in Chongdo and from $22.0\%$ to $26.8\%$ in Gyeongsan during the same period. However, the frequency of benzimidazoleresistant isolates was less than $4.0\%$ in Chochiwon and Youngduk during the same period. Benzimidazoleresistant isolates showed cross-resistance among benzimidazoles. On the other hand, none of the isolates showed cross-resistance to diethofencarb and carbendazim. Regardless of the year, the benzimidazole-resistant isolates of $EC_{50}$ higher than 500 $\mug%$ a.i./ml were isolated more frequently in mid and late season than in early season. In an orchard of Gyeongsan that had not been exposed to any fungicides for several years, the population of benzimidazole-resistant isolate had persisted without much fluctuation for three years. These results suggest that benzimidazole resistance of M. fructicola is becoming a problem in controlling brown rot and blossom blight of peach in regions like Chongdo and Gyeongsan.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권1호
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• pp.7-12
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• 2022

Farming practices that balance environmental friendliness with biodiversity are increasingly valuable. Wild plants on farmlands compete for nutrients with crops and create a crucial microhabitat and resources for animals such as natural enemies. Investigating farmlands and their surrounding plants with limited human and material resources has become an essential aspect of evaluating the agricultural ecosystem services. This study investigated plants in six agricultural long-term ecological research sites in Taiwan from 2017 to 2020 to determine the ideal season for investigation. Cluster analysis was performed to group habitats with similar plant composition, and the species-area curves of the clusters in each season were created. The results indicated that the agricultural ecosystem could be divided into farmlands, banks, orchards, and tea gardens. The habitats were divided into farmland, bank, Chia-Yi orchard, Gu-Keng orchard, and tea garden clusters. Ground plant cover can be investigated all year with at least 18 quadrats. However, if human and material resources are limited, 10 quadrats should be the minimum for farmlands in autumn and for the other microhabitats in spring. The minimum number of quadrats is 10 for banks, 17 for orchards, and 9 for tea gardens.

• The Plant Pathology Journal
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• 제39권1호
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• pp.136-140
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• 2023

Rice panicle blast is one of the most serious diseases threatening stable rice production by causing severe damage to rice yields and quality. The disease is easy to occur under low air temperature and frequent heavy rainfall during the heading season of rice. In 2021, a rice panicle blast severely occurred in the Jeonbuk province of Korea. The incidence area of panicle blast accounted for 27.7% of the rice cultivation area of Jeonbuk province in 2021, which was 13.7-times higher than in 2019 and 2.6-times higher than in 2020. This study evaluated the incidence areas of rice panicle blast in each region of Jeonbuk province in 2021. The weather conditions during the heading season of rice, mainly cultivated rice cultivars, and the race diversity of the Jeonbuk isolates were also investigated. It will provide important information for the effective control of the rice panicle blast.

• The Korean Journal of Ecology
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• 제26권4호
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• pp.189-197
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• 2003

남한산성 지역에서 춘계단명식물인 현호색 자연집단에 대해 2년간 종자생산의 특성을 조사하였다. 개화는 4월초에, 종자생산은 5월초에 일어나 개화로부터 종자생산까지는 30일이 소요되었으며 생식기관의 수가 감소하는 시기는 낙화 및 결실기 사이가 가장 큰 것으로 나타났다. 개체 당 생산하는 꽃의 수는 1∼13개, 종자의 수는 0∼76개, 열매 당 종자의 수는 0∼20개이었다. 한 개체 내에서 열매 당 종자생산량은 가장 아래에 위치한 꽃이 11.8개로 많았으며 상부로 이행할수록 급격히 감소하였다. 동일한 개체가 생산하는 종자의 수는 매년 큰 폭으로 변하였으며 작은 개체는 다음해 많은 수의, 큰 개체는 적은 수의 증자를 생산하였다. 생육초기 개화체의 비율은 개체의 크기(괴경의 부피)가 증가할수록 증가하였으며 가장 작은 크기 계급인 <100 ㎣에서 5.0%(1999)∼5.4%(2000)를, 600㎣≤ 에서 100%를 나타냈다. 한편, 각 계급별 평균 꽃의 수는 2000년이 1999년보다 많았다. 특히 900 ㎣≤에서는 6.5개(1999)와 13.2개(2000)로 현저한 차이를 보였다. 생육후기 개화체의 비율은 <100 ㎣에서 13.3%이었고 500 ㎣≤ 에서 100%이었다. 따라서 생육초기보다 개화체의 비율이 다소 높게 나타났다. 괴경의 체적이나 건중량의 크기에 따른 열매의 수 및 종자의 수는 대체로 증가하였지만 경향성은 뚜렷하지 않았고 동일 크기계급 내에서도 개체마다 편차가 심하였다. 한편, 엽면적이 증가할수록 열매의 수나 종자의 수는 뚜렷이 증가하였다. 따라서 종자의 생산량은 생육기간동안 광합성량과 관계가 깊은 것으로 볼 수 있었다.