• 제목/요약/키워드: Dry periods

검색결과 503건 처리시간 0.027초

Secondary Drying Effects on Garlic Quality after Low Temperature Storage (마늘의 저온저장 후 2차 건조가 품질에 미치는 영향)

  • Ning, Xiao Feng;Kang, Tae Hwan;Park, Jong Won;Han, Chung Su
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제42권9호
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    • pp.1452-1460
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    • 2013
  • The purpose of this study was to investigate secondary drying effects on garlic quality, and to define the optimal secondary drying conditions for garlic preservation. The secondary drying tests used garlic that was naturally dried once and stored at low temperature. After secondary drying, the garlic was stored in a warehouse at room temperature. Tests were performed at different low-temperature storage periods (60, 105, 150, 195, and 240 days), secondary drying temperatures (35 and $40^{\circ}C$), drying times (1, 2, 3 days), and room temperature storage periods (15, 30, and 45 days). The results were compared with a non-secondary drying condition control. In general, the $40^{\circ}C$-2 days dry conditions showed the lowest weight-loss rate (5%) and rotting rate during room temperature storage. The sprouting rate increased by 20% during the initial 15 day-room temperature storage, along with a small increase after 30 days of room temperature storage. Increases in drying temperature and the period of secondary drying conditions caused a decrease in firmness. In addition, the sprouting rate was 10% higher, and rotting rate 5~10% higher, for the non-drying condition, compared to drying conditions. Based on our results, the $40^{\circ}C$-2 days drying condition is the optimal secondary drying condition for garlic storage.

Improvement of Herbicide Use in Crop Production. X. Interpretations in Tank - mix Use of Aciflurofen and Haloxyfop - methyl for Weeding on Late - season Cropped Soybeans (Glycine max L.) (제초제(除草劑)의 사용법(使用法) 개발(開發)을 위한 연구(硏究) - X. 만파대두(晩播大豆)의 잡초방제(雜草防除)를 위한 Acifluorfen과 Haloxyfop-methyl의 혼용효과(混用效果) 해석연구(解析硏究))

  • Guh, J.O.;Lee, K.;Kim, D.K.;Hong, S.H.
    • Korean Journal of Weed Science
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    • 제5권1호
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    • pp.73-84
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    • 1985
  • 25 tank-mixed combinations between Haloxyfop-methyl at 0, 0.05, 0.1, 0.15 and 0.2 kg ae/ha and Acifluorfen at 0, 0.082, 0.163, 0.245 and 0.326 kg ai/ha were applicated at post-emergence on the late-season cropped soybean(Glycine max) fields predominated by grasses and assessed on the weeding efficacy. A most abundant weed species on the experimented fields were found at September (25 species). The broadleaved weed species and sedges were successively and proportionately emerged by the control rate of grass species. From the mono-treatment of each herbicide, Haloxyfop-methyl was recognized as a highly selective one between grasses and soybean, and Acifluorfen between broadleaf weeds and soybean, respectively. By combined application with both herbicides a synergistic weeding efficacy was detected on total weed species, however antagonistic or additive on each weed groups. Among other traits of soybean, stem dry weight was influenced by weed competitions during October, number of pods per plant during August and seed yields during whole periods. For most effective and reasonable weeding, no less than 0.4 kg ai/ha of each herbicides should be applicated in combinations.

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Weed Occurrence and Competitive Characteristic under Different Cultivation Types of Rice(Oryza sativa L.) - 5. Competition Period of Rice and Weed (수도(水稻) 재배유형별(栽培類型別) 잡초발생(雜草發生) 양상(樣相)과 경합특성(競合特性) - 제(第)5보(報), 잡초경합(雜草競合) 한계기간(限界期間))

  • Im, I.B.;Guh, J.O.
    • Korean Journal of Weed Science
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    • 제15권2호
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    • pp.105-114
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    • 1995
  • Differences in critical period of weed competition were investigated among five types of rice(Oryza sativa L.) cultivation. Increase in weed-free period resulted in 1-2 days delay of heading date in machine transplanting and direct-seeding as compared with complete weed-free plot. When weedy period increased, there was no difference in heading date in transplanting cultivations. In direct-seeding, however, weedy period of 7-10 weeks after seeding(WAS) resulted in 4-7 days delay of heading date, whereas further increase in the weedy period caused rather 5-6 days advance in heading date. Weed-free period did not significantly affect yield components in conventional hand transplanting. In machine transplanting with 30-day-old seedling decreases in percent ripening and 1,000-grain weight were caused by weeds emerged within 4 weeks after transplanting(WAT). All yield components were decreased due to weedy period in machine transplanting with 10-day-old seedling. In direct-seeding weedy periods caused to decrease in number of panicles, number of spikelets, percent ripening, and 1,000-grain weight were 8-9, 4-5, 3-4, and 8-10 WAS, respectively. The critical periods of weed competition were determined as the following. In conventional hand transplanting weed-free must be maintained for either 4 weeks after transplanting or the rest period after 8 WAT. In machine transplanting with 30-day-old seedling weed-free must keep for either 5 weeks after transplanting or the rest period after 8 WAT. In machine transplanting with 10-day-old seedling weeds must be removed for either 5 weeks after transplanting or the rest period after 7 WAT. Weed-free must be kept between 5 and 7 WAS in flood direct-seeded rice and between 6 and 9 WAS in dry direct-seeded rice.

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Effect of Cornstarch-Based Absorbent Polymer on the Growth of Cool Season Turfgrasses in Sand-Based Mixture (옥수수 전분이 주성분인 토양보습제 첨가가 모래 배양토에서 한지형 잔디의 생육에 미치는 영향)

  • Choi, Joon-Soo;Yang, Geun-Mo;Ahn, Sang-Hyun;Cho, Yun-Sik
    • Asian Journal of Turfgrass Science
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    • 제22권1호
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    • pp.75-84
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    • 2008
  • This study was carried out to examine the effects of cornstarch-based absorbent polymer (CAP) on the growth of cool season turfgrasses in sand-based soil mixture. Kentucky bluegrass + perennial ryegrass mixtures seeded at May 18 in 2006 on sand-based soil mixture. Sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$, sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) mixtures were compared. Ground coverage of sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) treatments showed 50% at a month after seeding. But the coverage of sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$ resulted in 36.7%. Mixing of CAP with sand was considered to be efficient method for increasing ground coverage as much as peat. Dry weight of turfgrass tiller at sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) were also significantly higher than sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$ mixtures at a month after seeding. Soil water retention at the sand + CAP $20g{\cdot}m^{-2}$, sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) mixing were lower than sand + peat (5%, v/v) and sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v) during the dry periods. From the results, the mixing of CAP with sand is useful to increased ground coverage of kentucky bluegrass and perennial ryegrass.

Effect of Developmental Stages on Glucosinolate Contents in Kale (Brassica oleracea var. acephala) (생장단계에 따른 케일 내 글루코시놀레이트 함량)

  • Lee, Heon-Hak;Yang, Si-Chang;Lee, Min-Ki;Ryu, Dong-Ki;Park, Suhyoung;Chung, Sun-Ok;Park, Sang Un;Lim, Yong-Pyo;Kim, Sun-Ju
    • Horticultural Science & Technology
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    • 제33권2호
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    • pp.177-185
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    • 2015
  • The aim of this study was to investigate the amounts of glucosinolates (GSL) in kale at various development stages. Kale varieties 'Manchoo Collard' and 'TBC' were cultivated from 20 February 2012 to 3 July 2013 in the greenhouse at Chungnam National University. During the cultivation periods, samples were harvested at 35, 63, 91, 105, 119, and 133 days after sowing (DAS) and the amount of GSL quantified by HPLC. Ten types of GSL (progoitrin, sinigrin, glucoalyssin, gluconapin, glucoiberverin, 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, gluconasturtiin, and neoglucobrassicin) were observed in 'TBC', whereas nine types of GSL (the same as above, except glucoiberverin) were identified in 'Manchoo Collard'. The amount of total GSL in 'Manchoo Collard' was comparatively higher at 133 DAS (mean $8.64{\mu}mol{\cdot}g^{-1}$) and lower at 35 DAS ($1.16{\mu}mol{\cdot}g^{-1}$ dry weight, DW) of cultivation. In the case of 'TBC', the amount of GSL was higher at 91 DAS (mean $13.41{\mu}mol{\cdot}g^{-1}$) and lower at 35 DAS ($0.31{\mu}mol{\cdot}g^{-1}$ dry weight, DW). Sinigrin was the most abundant GSL (57% of total GSL) in 'Manchoo Collard' at 133 DAS and was also highest (44%) in 'TBC' at 91 DAS. Together, progoitrin, sinigrin, glucobrassicin, and gluconasturtiin, the precursor of crambene, allylisothiocyanate, indol-3-cabinol, and phenethylisothiocyanate accounted for 94 and 78% of GSL in 'Manchoo Collard' and 'TBC', respectively. Our results demonstrate that the amounts of GSL, which have potential anti-carcinogenic activity, change during development in kale.

Effect of Mixed Liquid Fertilization on Growth Responses of Cherry Tomatoes and Soil Chemical Properties (생초미생물혼합액비의 시용이 방울토마토의 생육반응과 토양화학성에 미치는 영향)

  • Park, Ji-Suk;Lee, Min-Jin;Lee, Seo-Youn;Kim, Jong-Sung;Lee, Tae-Kyu;Ro, Hee-Myong;Kim, Sang-Jun;Jeon, Seung-Woo;Seo, Sang-Gug;Kim, Kil-Yong;Lee, Geon-Hyoung;Jeong, Byung-Gon
    • Horticultural Science & Technology
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    • 제33권2호
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    • pp.268-275
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    • 2015
  • We evaluated the effect of mixed liquid fertilizer (MLF) on growth responses of plants and soil chemical properties. To do so, a pot experiment with cherry tomatoes (Lycopersicon esculentum var. cerasiforme) using loam soil was conducted for 81 days in a temperature-controlled glasshouse, and four N fertilization treatments were laid out in a completely randomized design with three replicates: control (C), chemical fertilizer treatment (CF), and two rates (MLF-0.5 and MLF-1.0) of MLF treatment. Soils were periodically sampled and analyzed for pH, EC, total N, inorganic N and total C, and growth characteristics of cherry tomatoes were measured. During the experimental periods, the pH of MLF soils was higher than that of CF soils. Soil total-N content increased right after CF-application and ultimately decreased to the level of the control (C) soil, while MLF-application slightly increased the level of soil total-N and this level remained unchanged throughout the experiment. The levels of soil inorganic N content increased after application of CF or MLF, but the initial increase disappeared in 56 days after transplanting (DAT). The dry weight of shoots and roots increased in CF or MLF plants, while the number of fruit increased only in MLF plants. Whereas soluble solid contents were higher in MLF plants than in the other (C and CF) plants, the titratable acidity was not different among treatments. However, no consistent effect of N treatments on major elements of the organs of cherry tomatoes was found. The amounts of N taken up by plants were 0.91 g for CF, 0.61 g for MLF-1.0, 0.43 g for MLF-0.5, and 0.25 g for control treatments, resulting in greater N efficiency for CF than for MLF.

A Comparison of Dry Matter Yield and Nutritive Value in the Mixture Swards associated with Festulolium braunii(Festuca pratensis Huds. × Lolium multiflorum Lam.) (Festulolium braunii (Festuca pratensis Huds. × Lolium multiflorum Lam.)를 조합한 혼파초지의 건물수량 및 사료가치 비교)

  • Lee, In Duk;Lee, Hyung Suk
    • Journal of The Korean Society of Grassland and Forage Science
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    • 제19권4호
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    • pp.317-324
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    • 1999
  • This study was conducted to evaluate the dry matter yield and quality of mixture swards associated with Festulolium braunii(Festuca pratensis Huds. ${\times}$ Lolium multiflorum Lam.). The experiment was arranged in a randomized block design with four mixture types: A(control); orchardgrass(seeding rate 60%) + tall fescue 20% + Kentucky bluegrass 10% + white clover 10%, B; orchardgrass 60% + tall fescue 20% + Festulolium braunii 10% + white clover 10%, C; orchardgrass 60% + Festulolium braunii 20% + Kentucky bluegrass 10% + white clover 10%, and D; orchardgrass 30% + Festulolium braunii 30% + red clover 40%. This study was carried out from Sept. 1996 to Dec. 1998 at Chungnam National University. The DM yield of D mixture type was higher than that of other mixture types(P<0.05). Compared with A(control) mixture type, the DM yield of the B mixture type which substitutes Kentucky bluegrass with Festulolium braunii was higher, but the C mixture type which substitutes tall fescue with Festulolium braunii was lower than that of A(control) mixture type. The content of CP, NDF, ADF, hemi-cellulose and cellulose among mixture types shows no significant differdence. Howerever, the DMD was not significantly different among mixture types in 1997, but the DMD of C and D mixture type were significantly higher than those of other mixture types in 1998(P<0.05). On the otherhand, the yield of CP and DDM in D mixture types was higher than those of the other mixture types(P<0.05). In botanical composition, the Festulolium braunii percentage of B, C and D mixture type with mixed Festulolium braunii wasd highly maintained, especially D mixture type was ranging from 40% to 60% in experimental periods. Following the above result, It is the most favorable mixture method for Festulolium braunii to make use of top grass like orchardgrass + red clover. It is also recommened to substitute bottom grass like Kentucky bluegrass with Festulolium braunii rather than with tall fescue in A(control) mixture type.

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Human Impact on the Environment of Highland Central Mexico during the Pre-and Post-Conquest (멕시코 중부 고산 지역에서 스페인 식민 통치 시기를 전후하여 일어난 인위적 환경 변화)

  • Park, Jung-Jae
    • Journal of the Korean Geographical Society
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    • 제40권4호
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    • pp.428-440
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    • 2005
  • There is currently no agreement among archaeologists, environmental historians, and paleoecologists as to the relative significance of pre- and post-Conquest human impact on the environments of Highland Mexico. This paper presents the results of pollen, microscopic charcoal, dung fungal spore, isotope, and magnetic susceptibility analyses on ca. 4m sediment core. The coring site is Hoya Rincon de Parangueo, one of the seven maar lakes in the Valle do Santiago. Amaranthaceae pollen, one of important disturbance indicators and Zea mays pollen obviously indicate two periods of agricultural activities. The first period begins ca. 400 B.C. and ends ca. A.D. 850. The second begins around A.D. 1550 and continues to the present. During the first period, the degree of agricultural activities was related to periodical sunspot cycles and the most intense activities were present between ca. A.D. 150-ca. A.D. 400. The abrupt increase of $\delta^{18}O$ around 280cm may reflect that an important transition to a dry phase took place around A.D. 450. People probably stopped cultivating crops due to dry conditions prevailing since ca. A.D. 450. The second period, the post-Conquest, exhibits a dramatic increase of sporormiella, dung fungal spores resulted fron the introduction of cattle. Low Poaceae frequency and charcoal production and high $\delta^{13}C$ values, magnetic susceptibility, and organic contents all indicate the arrival of the Spanish. Most importantly, it seems that mesquite (Prosopis juliflora) could have benefits from declined fire frequencies caused by cattle grazing. The study area is now entirely dominated by woody plants like mesquite, which clearly demonstrates that serious vegetation change occurred in the study area.

Composting of Compostable Wet Household Wastes Using Waste Newspapers as Humidity Amendment (수분개선제로 폐신문지를 이용한 가정쓰레기의 퇴비화)

  • Yun, Eun-Jin;Park, Ju-Won;Seo, Jeoung-Yoon
    • Korean Journal of Environmental Agriculture
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    • 제19권1호
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    • pp.32-37
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    • 2000
  • Because the household garbage had high water contents, it is difficult to compost it without an additive. Therefore, this study was performed to investigate possibility of using the waste newspapers as a humidity conditioner for the household garbage composting. The maximum temperature was $66.0^{\circ}C$ in spring, $69.2^{\circ}C$ in summer, $60.9^{\circ}C$ in fall and $56.0^{\circ}C$ in winter for composting periods. The seasonal pH value reached around 8.5 after 1 week and then repeated fluctuation at the narrow range in spring and fall, while it was stabilized at the range of $8{\sim}9$ after increasing to 8.5 after 1 week in winter. The water content was reduced little in winter, while decreased significantly in the other seasons. The water content after 8 weeks was 22.2% in spring, 47.6% in summer, 25.5% in fall and 72.5% in winter. The mass was reduced rapidly during the first week of each season, but it did not show much decrease. The volume reduced after 8 weeks to 59%, 32%, 27%, and 34% in spring, summer, fall and winter respectively. Organic matter content decreased over the four seasons. Nitrogen contents were in the range of 0.7% to 2.2% during the four seasons. The contents of inorganic compounds based on dry matyter were in the range of $0.94{\sim}2.59%\;P_2O_5$, $1.23{\sim}1.87%\;CaO$, $0.37{\sim}0.46%\;MgO$, $0.55{\sim}1.98%\;K_2O$. Concentration of heavy metals(Hg, Cd, Pb, Cu, Cr, Zn, As) based on dry matter were less than the limiting value of the by-product compost.

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Effect of Nitrogen Application Level and Regrowth Period on Composition of Fatty Acid in Tall fescue and Bermudagrass (질소시비 수준 및 재생기간이 톨페스큐와 버뮤다그라스의 지방산조성에 미치는 영향)

  • Park, Hyung-Soo;Hwang, Kyung-Jun;Park, Nam-Gun;Kim, Young-Jun;Jeong, Ha-Yeon;Jo, Nam-Chul;Ko, Moon-Suck
    • Journal of The Korean Society of Grassland and Forage Science
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    • 제29권1호
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    • pp.43-50
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    • 2009
  • Two experiments were conducted to evaluate the effects of nitrogen (N) application level and regrowth period on the fatty acid (FA) concentration and forage production of tall fescue (Festuca arundinacea Schr.) and bermudagrass (Cynodon dactylon (L.) Pers.). N was applied at 0, 50 and 100 kg/ha, and swards were cut after regrowth periods (15d, 30d and 45d). Concentrations of Individual FA were determined by gas chromatography. FA composition of tall fescue contains a high proportion ($87{\sim}88%$) of total FA contents as palmitic (C16:0), linoleic (C18:2) and linolenic acid (C18:3). The FA composition was not affected by N application, but a longer regrowth period significantly (p<0.05) decreased the composition of linolenic acid (C18:3) and increased those of linoleic acid (C18:2). The FA composition of bermudagrass was not affected by N application, but a longer regrowth period significantly (p<0.001) decreased the composition of linoleic (C18:2) and linolenic acid (C18:3). Linoleic and linolenic acfd of tall fescue were higher than those of bermudagrass. Dry matter (DM) yield of bermudagrass was significantly (P<0.05) affected by N application level and regrowth period. DM yield was higher at high N application and was higher at longer regrowth period. The crude protein concentration was higher at high N application and was low at longer regrowth period. Application of nitrogen fertilizer Increases dry matter (DM) yield and crude protein (CP) content of bermudagrass. These studies demonstrate opportunities to affect the FA concentration and composition of FA in forage through management strategies, which could affect milk FA composition.