• 한국유기농업학회지
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• 제28권3호
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• pp.417-430
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• 2020

이상기후로 인한 건조 스트레스에 의해 식물의 기공전도도와 광합성의 감소로 생장과 작물생산량이 감소하는 피해가 발생하고 있다. 이러한 식물의 스트레스를 완화하는 유용 곰팡이를 선발하기 위해 국내 농경지에서 41 균주를 분리하였으며, 발아율 검사로 2종의 곰팡이를 선발하였으며, 식물검정을 통해 최종 Trichoderma sp. GL02를 선발하였다. GL02를 고추 식물체에 처리하였을 때, 대조구에 비해 기공전도도가 증가하고, MDA와 전기전도도는 감소하는 것으로 보아, GL02를 처리한 고추 식물체는 건조 스트레스가 완화되며, 건조 후 재관수하였을 때 회복도 효과적이었다. 이러한 결과는 GL02는 고추 식물체에 건조 스트레스를 완화시키는 유용한 소재로 사용될 수 있음을 시사한다. 또한, 추후 포장 실험을 통하여 Trichoderma sp. GL02의 건조 스트레스 완화 효과가 고추 생산량과 연관이 있는지 확인해 볼 예정이다.

• 한국토양비료학회지
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• 제51권1호
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• pp.61-70
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• 2018

This study was carried out to review and compare crop cultivations upon chemical properties of paddy soil and qualitative characteristics of rice in Sejong-city from a point of view of farming extension to rice farmers and to utilize the result of the study as a basic guideline for precise agricultural practice. The pH in soils of Sejong was about 6.1-6.6 and had no difference with an average pH of paddy soils in Chung-Nam with pH 6.1. However, the average of organic matter, calcium (Ca) and available silicate in Sejong was lower than the average of them in Chung-Nam. The yields of rice were higher in 2010 than in 2011 and 2012, and the protein contents of rice were the highest in 2011 while the lowest water contents of rice in 2011. The protein contents upon regions were the highest in 2011 with 6.1%, and the amylose contents were the highest in Yeondong-myun, Jeoneu-myun, and Yeonseo-myun in 2010 while Kumnam-myun and Jeondong-myun were the highest in 2012. With the increase of precipitation, the protein content level in rice was increased while the amylose content level tended to decrease. Correlations between the chemical properties of paddy soil and the quality of rice and between level of organic matter in soil and amylose contents were negative (r = -0.507), and the correlation between the moisture contents and amylose contents (r = 0.419) and between the water contents and whiteness (r = 0.485) were positive. Because the quantity and quality of rice yield is determined by the soil characteristics, the consultation to farmers for the proactive soil analysis and for the maintenance of stable level of pH, organic matter and available silicate based on historical results of analysis is highly recommended. Also, the analysis on the effect of the weather and the soil characteristics affecting the quality and quantity of rice would be another good way.

• 한국농공학회지
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• 제34권4호
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• pp.80-96
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• 1992

This study was carried out in order to determin optimum irrigation requirements and water management practices for normal growth of dry field crops in reclaimed tidelands, and apply m planning of the irrigation projects. Desalinization experiments were performed by water management practices in the experimental field with high salt concentration, and growth experiments were conducted by irrigation point treatments using tomato and beet with relatively high salt tolerance. The results obtained from this study were summarized as follows : 1. Leaching or rinsing-leaching method was found to be effective in desalinizing the reclaimed tideland with rather high permeability. In this case, the water requirement for desalinizing the root zone layer of 40cm in depth, was estimated to be 1,200mm in depth. 2.The gypsum treatment in the desalinization of reclaimed tidelands, was ineffective in water requirements ; however, it could produce the desired effect in the facility of desalinization and the shortening of desalinization period with the sustaining permeability, in case of the desalinization by leaching method. 3.The optimum irrigation point which maintains the salt concentration within salt tolerance and maximizes the crop yield in reclaimed tidelands of silt loam soil, was found to be pF 1.6 in tomato and pF 1.8 in beet. The interval of irrigation date within 2 days was proved to he effective in both cases. 4.The optimum irrigation requirement and the water reguirement for the prevention of salt rise during the growing period after transplanting, were estimated to be 602mm(6.7mm/day) and 232mm for tomato, respectively. 5.The optimum irrigation requirement and the water requirement for the prevention of salt rise during the growing period after transplanting, were estimated to be 261mm(3.7mm/day) and 66mm for beet, respectively.

• The Plant Pathology Journal
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• 제33권6호
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• pp.543-553
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• 2017

Sesame (Sesamum indicum) is an important oil seed crop of Asia. Yields can be negatively impacted by various factors, including disease, particularly those caused by fungi which create problems in both production and storage. Foliar diseases of sesame such as Alternaria leaf blight may cause significant yield losses, with reductions in plant health and seed quality. The work reported here determined the incidence of Alternaria species infecting sesame seeds grown in the Punjab, Pakistan. A total of 428 Alternaria isolates were obtained from 105 seed samples and grouped into 36 distinct taxonomic groups based on growth pattern and morphological characters. Isolation frequency and relative density of surface sterilized and non-surface sterilized seeds showed that three isolates (A13, A47 and A215) were the most common morphological groups present. These isolates were further identified using sequencing of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA) and the Alternaria major allergen gene (Alt a 1). Whilst ITS of rDNA did not resolve the isolates into Alternaria species, the Alt a 1 sequences exhibited > 99% homology with Alternaria alternata (KP123850.1) in GenBank accessions. The pathogenicity and virulence of these isolates of Alternaria alternata was confirmed in inoculations of sesame plants resulting in typical symptoms of leaf blight disease. This work confirms the identity of a major source of sesame leaf blight in Pakistan which will aid in formulating effective disease management strategies.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.96-103
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• 2007

Plant growth-promoting rhizobacteria (PGPR) have the potential to be used as microbial inoculants to reduce disease incidence and severity and to increase crop yield. Some of the PGPR have been reported to be able to enter plant tissues and establish endophytic populations. Here, we demonstrated an approach to screen bacterial endophytes that have the capacity to promote the growth of pepper seedlings and protect pepper plants against a bacterial pathogen. Initially, out of 150 bacterial isolates collected from healthy stems of peppers cultivated in the Chungcheong and Gyeongsang provinces of Korea, 23 putative endophytic isolates that were considered to be predominating and representative of each pepper sample were selected. By phenotypic characterization and partial 16S rDNA sequence analysis, the isolates were identified as species of Ochrobacterium, Pantoea, Pseudomonas, Sphingomonas, Janthinobacterium, Ralstonia, Arthrobacter, Clavibacter, Sporosarcina, Acidovorax, and Brevundimonas. Among them, two isolates, PS4 and PS27, were selected because they showed consistent colonizing capacity in pepper stems at the levels of $10^6-10^7CFU/g$ tissue, and were found to be most closely related to Pseudomonas rhodesiae and Pantoea ananatis, respectively, by additional analyses of their entire 16S rDNA sequences. Drenching application of the two strains on the pepper seedlings promoted significant growth of peppers, enhancing their root fresh weight by 73.9% and 41.5%, respectively. The two strains also elicited induced systemic resistance of plants against Xanthomonas axonopodis pv. vesicatoria.

• 한국농공학회논문집
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• 제62권3호
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• pp.85-94
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• 2020

Since the salinity of irrigation water is a critical constraint to the production of certain vegetable crops, salinity was considered as one of the most important factors of irrigation water. The purpose of this study were to monitor and assess the effects of saline irrigation water on strawberry and red radish growth in protected cultivation. One control and three treatments, which were differentiated according to the level of salinity in irrigated water, were employed for each vegetable to assess the effects of the irrigation with saline water. Monitoring has shown that using irrigation water with salinity above a certain level causes excessive accumulation of sodium (Na⁺) in both strawberry and red radish. Increased Na+ content was analyzed to be able to decrease the sugar content in strawberry. In addition, the salinity higher than the threshold level of irrigation water was found to reduce the growth and yield of strawberry and red radish. This study could contribute to suggest criteria for safe use of saline water in protected cultivation, although long-term monitoring is needed to get more representative results.

• 한국농공학회지
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• 제32권1호
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• pp.72-86
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• 1990

This study was carried out to get the basic information of irrigation plans for upland crops such as the optimum irrigation level and the project water requirement. Red peppers and cucumbers were cultivated in PVC pot lysimeters filled with 60cm deep clay loam soil. Four tensiometers were installed in each pot to measure the soil water pressure head. Six levels of irrigation were used. The results obtained from this study are summarized as follows: 1.The optimum irrigation level. The irrigation level of FC-PF2.7 was found to be the optimum level for both red pepper and cucumber with respect to the yield and the weight per fruit. In case of FC-PF2.7, total ET during the irrigation period were 1005.2mm for red pepper, and 429.6mm for cucumber, respectively. 2.soil moisture extraction patterns. Average soil moisture extraction patterns (SMEP)during the irrigation period were from 1st soil layer 43% : 32% : 16% : 9% for red pepper and 39% : 34% : 15% : 12% for cucumber, respectively. The extraction ratio of the upper soils showed very large values during the early stage of growth and decreased largely during the middle stage, and became larger in the last stage. 3.The project water requirement. Among the reference crop evapotranspiration(ETo) computation methods presented by FAO, the Penman method was found to be the best. The effective rainfall was computed by a modified USDA-SCS curve number equation. Availability ratios of the total rainfall during irrigation season were 59.2% for red pepper and 48.9% for cucumber, respectively. Net project water requirement of design year are 837.3mm for red pepper. and 502.Smm for cucumber, respectively.

• Current Research on Agriculture and Life Sciences
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• 제31권2호
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• pp.124-130
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• 2013

환경변화 중요성과 유전적 안전성은 최근에 증가추세의 형질전환 작물에 인식되고 있다. 본 실험은 건조저항성 형질전환체 작물의 유전적인 안전성과 환경변이에 따른 농업적인 특성을 분석하였다. 내건성 형질전환체인 CaMsrB2-8, 23과 모품종인 '일미' 및 일반품종을 대조구로 GM필드에서 작물학적 생육특성을 조사하였다. 농업적인 생육 특성에서 CaMsrB2-8, 23 계통은 모품종인 '일미'와 년차간, 지역별 평균으로 표현형은 유사하였다. 수량에서 년도별, 지역별 차이는 있지만 통계적인 유의성은 없었다. 현미의 미립특성에서 CaMsrB2-8, 23은 모품종인 '일미'와 차이를 보이지 않았다. 현미의 화학적 성분 분석에서 CaMsrB2-2 계통의 전분과 단백질함량은 모품종인 '일미'보다 일반품종인 '일품' 화학적 성분함량이 유사하였다. 본 실험결과에서 내건성 형질전환체인 CaMsrB2-8, 23는 GM 작물의 후대에서도 유전적인 안전성과 함께 수행될 수 있을 것으로 사료된다.

• 농약과학회지
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• 제5권1호
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• pp.1-11
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• 2001

2000년 기상의 특징은 봄철의 극심한 가뭄과 여름철의 이상고온 및 저온현상, 장마기 두차례의 태풍 및 가을철 집중호우에 의한 침수로 요약된다. 벼는 전년에 비해 잎 이삭도열병이 심하게 발생하였으며, 세균성벼알마름병, 깨씨무늬병이 전국적으로 발생하여 문제시되었다. 고추는 역병과 탄저병이 생육후기에 심하게 발생하여 큰 피해를 가져왔으며 토마토는 일부지역에서 시들음병이, 오이, 수박은 CGMMV, 흰가루병, 급성위조증상, 딸기는 흰가루병이 심하게 발생하였다. 마늘은 파종기의 잦은 강우와 겨울철의 많은 강설로 흑색썩음균핵병이 대발생하였고, 봄감자는 가뭄에 의하여 바이러스병이, 가을감자는 집중호우에 의한 침수로 무름병, 풋마름병이 심하게 발생하였으며 고구마는 여느해와 마찬가지로 덩굴쪼김병의 발생이 심하였다. 사과 배의 병해는 예년에 비해 발생이 경미하였고 맥류의 붉은곰팡이병은 봄철의 가뭄으로 발생이 거의 없었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.1300-1304
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• 2008

The fact that soil loss causing to increase muddy water and devastate an ecosystem has been appearing upon a hot social and environmental issues which should be solved. Soil losses are occurring in most agricultural areas with rainfall-induced runoff. It makes hydraulic structure unstable, causing environmental and economical problems because muddy water destroys ecosystem and causes intake water deterioration. One of three severe muddy water source areas in Soyanggang-dam watershed is Jawoon-ri region, located in Hongcheon county. In this area, many cash-crops are planted at illegally cultivated agricultural fields, which were virgin forest areas. The purpose of this study is to estimate soil loss with current land uses (including illegal cash-crop cultivation) and soil loss reduction with land use conversion from illegal cultivation back to forest. In this study, the Sediment Assessment Tool for Effective Erosion Control (SATEEC) ArcView GIS system was utilized to assess soil erosion. If the illegally cultivated agricultural areas are converted back to forest, it is expected to 17.42% reduction in soil loss. At the Jawoon-ri region, illegally cultivated agricultural areas located at over 30% and 15% slopes take 47.48 ha (30.83%) and 103.64 ha (67.29%) of illegally cultivated agricultural fields respectively. If all illegally cultivated agricultural fields are converted back to forest, it is expected that 17.41% of soil erosion and sediment reduction, 10.86% reduction with forest conversion from 30% sloping illegally agricultural fields, and 16.15% reduction with forest conversion from 15% sloping illegally agricultural fields. Therefore, illegally cultivated agricultural fields located at these sloping areas need to be first converted back to forest to maximize reductions in soil loss reduction and muddy water outflow from the Jawoon-ri regions.