• 한국응용곤충학회지
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• 제60권4호
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• pp.463-471
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• 2021

열대식물인 인도멀구슬나무(Azadirachta indica)는 병해충과 방제와 의학적인 목적으로 오랫동안 이용하였다. 본고에서는 님제의 활성성분인 아자디라크틴의 해충에 대한 곤충생장조절, 기피, 섭식저해, 산란억제 등 다양한 작용기작과 국내 이용현황에 대하여 고찰하였다. 국내 유통되는 친환경유기농자재 중에서 님제 제품은 총 57종이었다. 그중 효능효과가 표시된 자재는 7종이었고 평균 아자디라크틴 함량은 0.38%로써 세계적으로 유통되는 평균 함량 2.1%와 비교할 때 약 5.5배 낮았다. 국내에서 님제의 방제효과에서 진딧물은 실험에서 다소 변이는 있었으나 대부분 90% 이상의 방제효과를 보였다. 꽃매미 약충에 누적살충률은 73~77%를 보였고, 총채벌레에 대한 방제가는 50~72% 범위로 살포효과가 인정되었다. 노린재와 나방류에 대한 방제효과는 대체적으로 낮았다. 본고는 유통되는 님제품의 이해와 실험자료의 해석에 필요한 주요한 정보를 제공해줄 수 있을 것으로 기대된다.

• Horticulture, Environment, and Biotechnology : HEB
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• 제59권6호
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• pp.805-813
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• 2018

Vanda is an aerial tropical orchid native to Thailand and nitrogen (N) fertilizer is mainly used to promote its growth and quality. However, little is known about the characteristics of N absorption and assimilation in Vanda. The objective of this study was to determine the appropriate source of N for Vanda cultivation. In this experiment, shoots and roots of Vanda 'Ratchaburi Fuchs-Katsura' were sprayed weekly with 100 ml of $^{15}N$ tracer solution (1) 10 mM of $^{15}NO_3{^-}$, (2) 5 mM of $^{15}NO_3{^-}$ plus 5 mM of $NH_4{^+}$, (3) 5 mM of $NO_3{^-}$ plus 5 mM of $^{15}NH_4{^+}$ and (4) 10 mM of $^{15}NH_4{^+}$. The results indicated that plants fed with a combined N fertilizer gave the highest of $^{15}N$ use efficiency ( $^{15}NUE$) of about 21.8%, 30 days after the first feeding (DAF), compared with those fed sole sources of $^{15}NO_3{^-}$ (21.0%) and $^{15}NH_4{^+}$ (16.6%). However, a sole nitrate fertilizer or combination fertilizer did not significantly affect the total N and labelled N content. Alanine was a major amino acid found in leaves and roots at 7 DAF, whereas glutamine was mainly found in stems. At 30 DAF, tyrosine and alanine became major components in the leaves, and glutamine decreased in stems when plants were fed with a single $^{15}NH_4{^+}$ source.

• The Plant Pathology Journal
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• 제37권6호
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• pp.607-618
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• 2021

The pepper anthracnose fungus, Colletotrichum scovillei, causes severe losses of pepper fruit production in the tropical and temperate zones. RAC1 is a highly conserved small GTP-binding protein in the Rho GT-Pase family. This protein has been demonstrated to play a role in fungal development, and pathogenicity in several plant pathogenic fungi. However, the functional roles of RAC1 are not characterized in C. scovillei causing anthracnose on pepper fruits. Here, we generated a deletion mutant (𝜟Csrac1) via homologous recombination to investigate the functional roles of CsRAC1. The 𝜟Csrac1 showed pleiotropic defects in fungal growth and developments, including vegetative growth, conidiogenesis, conidial germination and appressorium formation, compared to wild-type. Although 𝜟Csrac1 was able to develop appressoria, it failed to differentiate appressorium pegs. However, 𝜟Csrac1 still caused anthracnose disease with significantly reduced rate on wounded pepper fruits. Further analyses revealed that 𝜟Csrac1 was defective in tolerance to oxidative stress and suppression of host-defense genes. Taken together, our results suggest that CsRAC1 plays essential roles in fungal development and pathogenicity in C. scovilleipepper fruit pathosystem.

• 한국자원식물학회지
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• 제34권6호
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• pp.555-565
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• 2021

Melon fruits are a year-old plant in the family Cucurbitae and are the most cultivated fruit in tropical countries. Melon flesh is an important source of anti-cancer, antioxidant effects, attracting attention as a functional food. We investigated the morphological properties, β-carotene content, and cucumisin activity of seeds of 58 melon genetic resources. Melon resources have shown various morphological properties. Melons grouped by morphological properties were the five groups. β-carotene content varied between 82.34 mg/kg, 86.75 mg/kg, 25.56 mg/kg, 86.25 mg/kg, and 54.65 mg/kg. Between β-carotene, cucumisin activity and other quantitative fruit morphological properties, the color of the pulp and the firmness of the pulp had a significant amount of correlation between the β-carotene content. However, cucumisin activity and β-carotene content had significant negative correlation, and the color of the fruit and shape of the fruit had significant negative correlation with β-carotene content and activity of cucumisin. Our study vindicated that high diversity in melon morphological characters of genetic sources that provide beneficial baseline data for the future and in the activity of β-carotene and cucumisin, and these results could predict indicators of β-carotene content by the length of leaf, the width of fruit, the length of joint, and the length of seed, and collectively the morphological properties of melons could help predict indicators of β-carotene content and help develop functional sarcoma and farmhouse cultivation.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.46-46
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• 2020

Finger millet is more nutritious than other and millets and widely cultivate in tropical regions of the world. Furthermore, it is more tolerant against biotic and abiotic stresses such as pest, drought and salt. For this reason, finger millet is one of the putative crops to introduce and cultivate on reclaimed land and prepare the global climate exchange in Korea. In present study, genetic diversity and structure of different populations of finger millet from Africa and South Asia was examined at molecular level using newly developed EST-Simple Sequence Repeat (EST-SSR) markers. In total, 46 primers produced 292 alleles in a size range of 100-500 bp and mean Polymorphism Information Content (PIC) and Marker Index (MI) were 0.372 and 1.04, respectively. 46 primers showed polymorphism and 21 primers were identified as having a PIC value above 0.5. Principal coordinates analysis and the dendrogram constructed out of combined data of both markers showed grouping of finger millet accessions to their respective area of collection. The 156 accessions were more classified into four groups, such as three groups of Africa collection and one group of Asia. Results of present study can be useful in identifying diverse accessions and management of this plant resource. Moreover, the novel SSR markers developed can be utilized for various genetic analyses in this species in future.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.233-238
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• 2007

Intestinal helminths and schistosomiasis among school children were investigated in an urban and some rural communities of Ogun State, southwest Nigeria. Fecal samples of 1,059 subjects (524 males, 535 females) aged 3-18 years were examined using direct smear and brine concentration methods between June 2005 and November 2006. The pooled prevalence of infection was 66.2%. Ascaris lumbricoides showed the highest prevalence (53.4%) (P < 0.001) followed by hookworms (17.8%), Trichuris trichiura (10.4%), Taenia sp. (9.6%), Schistosoma mansoni (2.3%), Strongyloides stercoralis (0.7%), Schistosoma haematobium (0.6%), and Enterobius vermicularis (0.3%). The prevalences of A. lumbricoides, hookworms, Taenia sp., S. mansoni, and S. stercoralis in the urban centre were similar (P > 0.05) to those in the rural communities. The fertile and infertile egg ratios of A. lumbricoides in the urban centre and the rural communities were 13: 1 and 3.7: 1, respectively. Each helminth had similar prevalences among both genders (P > 0.05). The prevalence of A. lumbricoides increased significantly with age (P < 0.001). The commonest double infections were Ascaris and hookworms, while the commonest triple infections were Ascaris, hookworms, and Trichuris. The study demonstrates the need for urgent intervention programmes against intestinal helminthiases and schistosomiasis in the study area.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.986-993
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• 2001

In balance experiments with rats either 25 or 50% of the casein protein in the control diet was replaced with one of the following eight sun-dried tropical biomass products: water spinach plants (WS) (Ipomoea aquatica Forsk), leucaena leaves (LL) (Leuceana leucocephala), duckweed plants (DW) (Lemma minor L.), groundnut foliage (OF) (Arachis hypogaea L.), trichantera leaves (Tric) (Trichantera gigantea), indicago leaves (Ind) (Indigofera hirsuta), mungbean foliage (Mb) (Phaseolus aureus), and cassava leaves (CL) (Manihot esculenta Crantz). The experiment included 102 rats with six individuals per treatment group. In three of the 16 biomass treatment groups, feed intake and weight gain of the rats were unacceptably low, and therefore they were excluded from the statistical evaluation, The crude protein (CP) content of the biomass products varied between 20.9% (Tric) and 33.2% (DW), whereas the content of NDF varied between 18.5% (Ind) and 32.2% (DW) of dry matter (DM). The total content of essential amino acids (g/16 g N) was comparable with that of alfalfa meal, except for GF and Tric, which were inferior. Between plant species, differences in dietary digestibility of organic matter (dOM) and CP (dCP) were observed (p<0.001). Also, the replacement level negatively influenced dOM and dCP (p<0.001). The lowest values for dOM (p<0.001) were observed for diets including biomass products with the highest content of NDF (OF, Tric, Mb, LL). Digestibility of CP was negatively affected by level of protein replacement. Significant (p<0.001) differences were found in N-retention and biological value among diets with different biomass products. The most favourable overall results were obtained for DW, WS and CL. The main factors affecting the nutritive value of the diets tested were their NDF content, dCP and AA profile of the biomass. Also antinutritive component(s) may have influenced the process of digestion and metabolism of some of the biomass products.

• 한국토양비료학회지
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• 제20권2호
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• pp.123-129
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• 1987

수도(水稻)의 축산폐수(畜産廢水) 피해(被害)에 대한 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)를 구명(究明)하기 위하여 사양토(砂壤土)에서 2년간(年間) pot 시험(試驗)한 결과(結果)는 다음과 같다. <시험(試驗) 1> 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)(1985) 1. 수도수량(水稻收量)은 상시담수구(常時湛水區)가 간단관수구(間斷灌水區) 보다 많다고 개량제(改良劑) 시용(施用)으로 증수(增收)되는 경향(傾向)이였으며 개량제중(改良劑中) Zeolite와 규회석(硅灰石)이 효과(效果)가 좋았음. 2. 고중(藁重) 및 식물체중(植物體中) 질소함량(窒素含量)은 시용질소(施用窒素) 및 폐수관개량(廢水灌漑量)이 많을수록 증가(增加)하였으나 개량제(改良劑) 시용(施用)으로 감소(減少) 하였음. <시험(試驗) 2> 규회석(硅灰石) 시용효과(施用效果)(1986) 3. 수도수량(水稻收量)은 규회석(硅灰石) 시용량(施用量)이 증가(增加)할수록 증수(增收)되었으며 규회석시용(硅灰石施用)에 의(依)한 증수원인(增收原因)은 등숙율(登熟率) 및 수당입수(穗當粒數)의 증가(增加)에 있었고 질소시용량(窒素施用量)이 3g/pot (관행(慣行))구(區)에서는 규회석(硅灰石) 60g/pot 시용(施用)이 적량(適量)으로 생각되었다. 4. 불임수수(不稔穗數)는 시용질소(施用窒素) 및 폐수중(廢水中) 질소농도(窒素濃度)가 증가(增加)됨에 따라 증가(增加)하는 경향(傾向)이었으며 규회석시용(硅灰石施用)으로 크게 감소(減少)되었다.

• 한국응용곤충학회지
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• 제57권2호
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• pp.77-85
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• 2018

국내 분포조사가 되어 있지 않은 긴꼬리가루깍지벌레와 붉은몸긴꼬리가루깍지벌레를 대상으로 3년간(2015~2017년) 281지점의 관엽식물과 666지점의 과수를 조사하였다. 관엽식물의 경우 긴꼬리가루깍지벌레는 34지점에서 발견되었고, 붉은몸긴꼬리가루깍지벌레는 87지점에서 발견되었으나 과수에서는 두 종 모두 발견되지 않았다. 분포조사를 통해 채집한 긴꼬리가루깍지벌레와 붉은몸긴꼬리가루깍지벌레는 실내사육하며 온도별 발육특성을 조사하였다. 긴꼬리가루깍지벌레 암컷 약충은 $14^{\circ}C$에서 정상적인 발육을 하지 못하였으며, $16^{\circ}C$에서는 361.4일로 발육기간이 가장 길었으며 $32^{\circ}C$에서는 39.0일로 가장 짧았다. 긴꼬리가루깍지벌레 암컷 성충수명은 $28^{\circ}C$에서 71.7일로 가장 짧았으며, 산자수의 경우 $32^{\circ}C$에서 177.7마리로 가장 많았다. 붉은몸긴꼬리가루깍지벌레 암컷 약충은 $12^{\circ}C$에서 정상적인 발육을 하지 못하였으며 $14^{\circ}C$에서 184.9일로 발육기간이 가장 길었으며, $28^{\circ}C$에서는 21.5일로 가장 짧았다. 붉은몸긴꼬리가루깍지벌레 암컷 성충수명은 $28^{\circ}C$에서 51.5일로 가장 짧았으며, 산자수의 경우 $28^{\circ}C$에서 143.8마리로 가장 많았다. 세대순증가율($R_0$)과 내적자연증가율($r_m$)은 긴꼬리가루깍지벌레는 각각 $32^{\circ}C$에서 162.3, 0.127이며, 붉은몸긴꼬리가루깍지벌레는 각각 $28^{\circ}C$에서 98.3, 0.139로 가장 크게 나타났다. 따라서, 긴꼬리가루깍지벌레와 붉은몸긴꼬리가루깍지벌레의 최적 온도는 각각 $32^{\circ}C$와 $28^{\circ}C$로 판단되며 국내에서의 월동은 불가능한 것으로 보인다.

• 한국응용곤충학회지
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• 제22권2호
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• pp.52-66
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• 1983

The brown planthopper, N. lugens (Stal), has become a serious pest of rice in tropical Asia during the last decade. At high pest density, its feeding damage causes 'hopperburn' or complete wilting and drying of the rice plant. It also transmits grassy and ragged stunt virus diseases. The estimated losses caused by the pest in tropical Asia exceed $US\$300$ millions. While cultivation of resistant rice varieties has proved to be highly effective against the pest, their long-term stability is threatened because of the evolution of prolific biotypes which can destroy these varieties. At present, identification of biotypes is based principally on the differential reactions of host rice varieties to the pest and on host-mediated behavioral and physiological responses of the pest. Recent findings of morphological differences in adult rostrum, legs, and antennae, body parts that possess receptors for host plant location and discrimination, and cytological differences in N. lugens populations maintained as stock cultures strongly complement other biotype studies. So far, three N. lugens biotypes have been identified in the Philippines. Biotype I can survive on and damage varieties that do not carry and genes for resistance, while Biotype 2 survives on resistant varieties carrying Bph 1 gene and Biotype 3 on varieties carrying gene bph 2. However, none of these biotypes can survive on varieties with genes Bph 3 or bph 4. Several varieties which are resistant in the Philippines are susceptible in India and Sri Lanka as the South Asian biotypes of N. lugens are more virulent than Southeast Asian biotypes. To monitor the pest biotypes in different geographical regions and to identify new sources of resistance, an International Brown Planthopper Nursery has been established in many cooperating countries. The evolution of biotypes is an exceedingly complex process which is governed by the interactions of genetic and biological factors of the pest populations and the genetic makeup of the cultivated varieties. While the strategy for sequential release of varieties with major resistance genes has been fairly successful so far, the monegenic resistance of these varieties makes them vulnerable to the development of the pest biotypes. Therefore, present breeding endeavors envisage utilizing both major and minor resistance genes for effective control of the pest.