• Applied Biological Chemistry
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• v.47 no.4
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• pp.403-408
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• 2004

We studied active substances like crude cell wall components, crude protein, composing amino acids and free amino acids including orinithine cycle-related amino acids such as asparagine, ornithine and citrullin in fully ripe fruits of Korean native squash, Cucurbita moschata Poir. Crude protein content of 'Jeju 2' was the highest with $2,830\;{\mu}g/g$, while 'Sangju' was the lowest with $1,319\;{\mu}g/g$. Regarding the contents of crude cell wall components, fruit 'Kanghaw' was the highest with 2,961 mg% while 'Namhea' was the lowest with 1,582 mg%. Pectin contents of crude cell wall components were the highest in 'Kanghaw' (2,198 mg%) followed by 'Jeju 2' (2,178 mg%) and 'Jeju l' (1,461 mg%). The main contents of amino acids in squash were glutamic acid, aspartic acid, lysine, leucine and valine, which comprised to be more than 50% of total amino acid contents. Especially, in 'Jeju 2' aspartic acid and threonine were not detected. In fully ripe fruits, a total of 34 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 50% of the total free amino acids were aspartic acid and asparagine, and also all varieties were detected in ornithine, citrullin, and arginine, which are related to Ornithine cycle. There was a big difference in the contents of arginine in all varieties whereas the contents of ornithine and citrullin were very similar. 'Teaan' 29.34% was 7 times higher than 'Namhea' 4.30% in regards to arginine contents.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.1-5
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• 2011

A new powdery mildew resistant squash (Cucurbita moschata Duch.) 'Miso' was bred from a cross between powdery mildew resistant true variety 'Sangol' and powdery mildew susceptible inbred line 'Seoulmadi' at National Institute of Horticultural & Herbal Science (NIHHS). The 'Miso' variety was vigorous and highly resistant to powdery mildew. It showed white green fruit color. The variety yielded 21.3MT/ha which is 52% more than control variety.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.93-105
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• 2015

This study was performed to analyze genetic relationships of the four major cucurbitaceous crops including watermelon, melon, cucumber, and squash/pumpkin. Among 120 EST-SSR primer sets selected from the International Cucurbit Genomics Initiative (ICuGI) database, PCR was successful for 51 (49.17%) primer sets and 49 (40.8%) primer sets showed polymorphisms among eight Cucurbitaceae accessions. A total of 382 allele-specific PCR bands were produced by 49 EST-SSR primers from 24 Cucurbitaceae accessions and used for analysis of pairwise similarity and dendrogram construction. Assessment of the genetic relationships resulted in similarity indexes ranging from 0.01 to 0.85. In the dendrogram, 24 Cucurbitaceae accessions were classified into two major groups (Clade I and II) and 8 subgroups. Clade I comprised two subgroups, Clade I-1 for watermelon accessions [I-1a and I-1b-2: three wild-type watermelons (Citrullus lanatus var. citroides Mats. & Nakai), I-1b-1: six watermelon cultivars (Citrullus lanatus var. vulgaris S chrad.)] a nd C lade I -2 for melon and cucumber accessions [I-2a-1 : 4 melon cultivars(Cucumis melo var. cantalupensis Naudin.), I-2a-2: oriental melon cultivars (Cucumis melo var. conomon Makino.), and I-2b: five cucumber cultivars (Cucumis sativus L.)]. Squash and pumpkin accessions composed Clade II {II-1: two squash/ pumpkin cultivars [Cucurbita moschata (Duch. ex Lam.)/Duch. & Poir. and Cucurbita maxima Duch.] and II-2: two squash/pumpkin cultivars, Cucurbita pepo L./Cucurbita ficifolia Bouche.}. These results were in accordance with previously reported classification of Cucurbitaceae species, indicating that watermelon EST-SSRs show a high level of marker transferability and should be useful for genetic study in other cucurbit crops.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.90.2-91
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• 2003

In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichoderma harzianum YC459 (TORY), a biocontrol agent for the gray mold rot of vegetables caused by B. cinerea The mechanism for selective colonization of senescent floral tissues by T. harzianum YC459 was elucidated using fresh and senescent (Hays and 14days after flowering, respectively) floral tissues of zucchini squash (Cucurbita moschata Duchesne). The spores of T. hrzianum YC459 were produced more on agar and liquid culture media supplemented with 5％ dry powder of senescent floral tissues than fresh tissues during 15days. Mycelial growth was also much better in the media with senescent tissues than with fresh tissues. Enzyme activities of amylase, polygalacturonase and cellulase in the liquid media which might be involved in the colonization of tissues by T. harzianum YC459 were compared. The activities of three enzymes were much higher in the media with senescent floral tissues than with fresh floral tissues reaching to the maximum during 9 to 12days of incubation. Based on the results, the removal of senescent floral tissues, a possible inoculum source of the pathogen, may be another mechanism for biocontrol of gray mold rot of vegetables by T. harzianum YC459.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.198-205
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• 1999

Cucurbitaceous vegetable crops grown in greenhouses in Korea were surveyed from 1995 to 1997. Incidence of Sclerotinia rot was as high as $30{\sim}70%$ at its maximum on Cucumis melo var. reticulatus (netted melon), Cucumis sativus (cucumber), Cucurbita moschata (pumpkin) and Cucurbita pepo (summer squash) but relatively low on Citrullus lanatus (watermelon) and Cucumis melo var. makuwa (oriental melon). Symptoms of Sclerotinia rot developed on stems of all the cucurbits, fruits of five cucurbits except C. lanatus, petioles of two Cucurbita spp. and leaves of C. moschata. A total of 126 isolates of Sclerotinia sp. were obtained from the lesions and identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The fungus was very frequently isolated from stems and fruits of the cucurbits but rarely from petioles and leaves. Six isolates of the fungus were pathogenic to six cucurbits tested although there was some difference in virulence among the isolates to some of the hosts. C. lanatus was the most susceptible to the isolates, whereas C. melo var. makuwa was the most resistant. C. melo var. reticulatus and C. sativus were relatively susceptible to the isolates, and C. moschata and C. pepo relatively resistant.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.614-622
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• 2014

Melons (Cucumis melo L.) are generally grafted onto Cucurbita rootstocks to manage soilborne pathogens such as Monosporascus root rot and v ine decline (MRR/VD) and Fusarium wilt. However, g rafting onto Cucurbita rootstocks reportedly results in the reduction of fruit quality. In this study, the resistance to MRR/VD, yield, and fruit quality of melons grafted onto melon rootstocks were evaluated under greenhouse conditions. Eight melon rootstocks (R1 to R8) were used and the inodorus melon 'Homerunstar' was used as scion. Melon rootstocks R1 to R6 were selected based on resistance to MRR/VD under greenhouse conditions. Non-grafted 'Homerunstar' and plants grafted onto squash interspecific hybrid 'Shintozwa' rootstock (Cucurbita maxima D. ${\times}$ C. moschata D.) served as controls. Grafted melons were cultivated in the greenhouse infested with Monosporascus cannonballus during two growing seasons (summer and autumn). The responses to MRR/VD, yield, and fruit quality differed depending on the rootstocks and growing season. The melons grafted onto 'Shintozwa' exhibited less severe disease symptoms and higher survival rates than non-grafted melons in both seasons. While the melon rootstocks in the summer cultivation did not increase the survival rate compared to non-grafted melons, the melon rootstocks R1 and R2 in the autumn cultivation led to higher survival rates. The melon rootstocks resistant to MRR/VD increased the percentage of marketable fruits and marketable yields. Grafting onto the melon rootstocks caused little or no reduction of fruit quality such as low calcium content, fruit softening, and vitrescence, especially in lower-temperature autumn season. Accordingly, these results suggest that grafting onto the melon rootstocks may increase the tolerance to MRR/VD and the marketable yield without a reduction of fruit quality.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.251-266
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• 1990

Extrafloral nectaries have been shown in many studies to promote mutualistic interactions between plants and insects(usually ants) that visit the glands. The insects gain sugars, water and amino acids secreted by the extrafloral nectaries and benefit the plants by reducing the damage caused by plant's inseet herbivores. Little is known about the occurrence of extrafloral nectaries in plants growing in Asia. To learn about the occurrence of extrafloral nectary bearing plants in Korea, living plants and herbarium material were examined for the glands. In addition, the cover of plants with extrafloral nectaries and the proportion of woody plants with extrafloral nectaries were measured in three forest communities on Kangwha Island. 131 species of plants belonging to 53 genera and 30 families were found to have extrafloral nectaries. These 131 species comprise about 4.0% of Korea's flora, a highet percentage of extrafloral nectary bearing plants than occurs in the studied areas of North America. Extrafloral nectary bearing plants occupied 7, 23 and 55% of the covers and comprised 15, 21 and 15% of the woody plants in the three different forests, a significant level of occurrence. Many important Korean crop plants were found to have extrafloral nectaries including : sesame (Sesamum indicum L.), squash (Cucurbita moschata Duchesne), sweet potato (Ipomoea batatas Lam), persimmon (Diospyros kaki Thunb.) cotton (Gossypium indicum Lam.), mung bean (Phaseolus radiatus L.), red bean (Phaseolus angularis W.F.), peach (Prunus persica (L) Batsch.), plum (Prunus salicina Lindl.). Many of these cultivated and wild plants may receive protection by ants and other beneficial insects that visit their extrafloral nectaries.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.770-776
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• 2013

The aim of this study was to investigate the antioxidant and anti-cancer activities of squash leaf extract (SLE) in vitro. The total polyphenol and flavonoid levels of SLE were 263.4 mg gallic acid equivalent/100 g and 73.6 mg quercetin equivalent/100 g, respectively. The radical-scavenging activity of SLE at the concentration of 300 ${\mu}g/mL$ was 69.4%. SLE significantly inhibited human cancer cell growth (by 60.6-87.9% in HCT116 colon cancer cells and by 73.4-86.4% in H1299 lung cancer cells at the concentrations of 37.5, 75, and 150 ${\mu}g/mL$) and attachment (by 28.4% in HCT116 and by 16.8% in H1299 at the concentration of 150 ${\mu}g/mL$). SLE also altered nucleus morphology and increased nuclear staining intensity (by 42.8-58.2% in HCT116 and by 25.5-32.9% in H1299 at the concentrations of 37.5 and 75 ${\mu}g/mL$), indicating its apoptosis-inducing activity. These results demonstrate the antioxidant and anti-cancer activities of SLE in vitro.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.211-221
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• 2012

The fourth leaves (younger leaves) amongst extended 4-upper leaves in 18 squash cultivar were the highest tolerance to the paraquat application, followed by third, the second, and the first leaves (older leaves). The forth leaves in Joongangaehobak showed more than three times higher tolerance to the paraquat application than did the first leaves. When the combining of water extract from the fourth leaves with paraquat were applied to the leaves and stems of maize, the paraquat phytotoxicity in maize was reduced compared to the paraquat application alone. Therefore, this study continued to investigate if the phytotoxicity inhibitor exist in the fourth leaves. The water extract in the fourth leaves were isolated by silica gel column chromatography, Sephadex LH-20 column chromatography, TLC, and HPLC, and the substance in the extract was speculated as a malic acid by identifying through NMR. The mixture malic acid and paraquat were applied to the maize to verify the application effect of malic acid on paraquat toxicity. The 100 ${\mu}M$ of paraquat application alone showed 62% of paraquat toxicity to the corn leaves, while the combined application of 100 ${\mu}M$ paraquat with malic acid at 0.1, 0.3, 0.5, and 1.0% did not show the symptom.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.39-39
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• 2020

호박(Cucurbita spp.)은 박과 호박속 식물로 원산지는 열대 남아메리카로 추정되며 1년생 혹은 다년생 초본으로서 우리나라를 포함한 전 세계에서 널리 분포하고 있다. 호박은 비타민A와 비타민C가 풍부하고 이뇨작용 효과가 탁월해 피부를 좋게 하고 부기를 빼주는 것으로 보고되고 있다. 본 연구에서는 농업유전자원센터에서 보유한 호박속 자원의 내력과 형태적인 특성을 그룹화하여 자원 활용을 위한 기초자료를 제공하고자 하였다. 농업유전자원센터에서 보유한 호박속 등록자원은 총 5종(C.pepo, C. moschata, C.maxima, C.argyrosperma, C .ficifolia) 1,640자원으로 주요 원산지는 한국 589자원(35.9%), 미국 122자원(7.4%), 러시아 79자원(4.8%), 멕시코 49자원(4.2%), 터키 56자원(3.4%)이었으며 국내 원산의 경우 강원도에서 수집된 자원이 66자원으로 가장 많았다. 전체 1,640 자원 중 재래종은 733자원(44.7%)을 차지하였으며 다음으로는 육성품종이 133자원(8%)으로 많았다. 생장형이 조사 된 301자원 대부분이 덩굴성이며 준왜성 16자원, 왜성 14자원이 있었다. 호박은 과실 모양과 색, 잎 모양, 줄기 모양 등 생육 특성이 매우 다양하게 조사 되었으며 과경 등 몇 가지 특징은 완벽하지 않지만 종(species)을 구분하는 간이적인 지표로 사용되는 것으로 조사되었다. 흰가루병 저항성 자원은 조사 된 1,170 자원 중 우리나라 재래종인 참호박(IT104575)을 포함한 7자원이 조사되었다. 293개 자원의 과실당도는 2.2~15.4brix까지 다양했으며 당도 12brix 이상 자원은 IT200650을 포함하여 6자원이 조사되었다. 본 연구에서 조사된 호박속 자원의 내력 및 생육 특성은 육종소재의 기초 정보로서 이용되고 있으며 자원 내력정보의 보완, 형질과 기능성 물질 분석 등 추가적인 연구를 통해 연구소재의 기초 정보로서 활용의 가치가 더 커질 것으로 보인다.