• 제목/요약/키워드: transplanting time

검색결과 413건 처리시간 0.03초

생육중기 벼 군락 내 기온의 연직구조 (Air Temperature Profile within a Partially Developed Paddy Rice Canopy)

  • 윤영관;윤진일;김규랑;박은우;황헌;조성인
    • 한국농림기상학회지
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    • 제2권4호
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    • pp.204-208
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    • 2000
  • 벼 군락의 기온 연직구조에 관한 연구는 일반적으로 출수 이후 등숙기에 완전히 형성된 군락을 대상으로 한 것이므로 병해충 예찰모형의 구동 등 실용적으로 많이 요구되는 생육중기의 미형성 군락에 관한 정보를 보완하기 위해 이앙 후 한 달째부터 출수 직전까지 기온을 연속 측정하였다. 별도의 차광 혹은 환기장치가 불필요한 직경 0.003mm E형 미세선 열전대를 관개수면 위 l0cm부터 100cm까지 10cm 간격으로 10개를 설치하였으며, 비교를 위해 150cm 위치에 1개를 추가설치 하였다. 자료는 10초 간격으로 측정하고 그 10분 평균값을 취하였으며 분석은 한 시간 단위로 수행하였다. 맑은 날 자료에 의하면 일출 이후 초관부(최대엽면적 부위) 기온은 외기온과 거의 같은 비율로 상승하나, 그 아래쪽으로 갈수록 태양고도가 높아지기 전까지는 온도 상승이 상대적으로 지연된다. 오후에 태양고도가 낮아지기 시작해도 군락 외부와 초관부의 기온은 관측노장의 일 최고기온 발생시각까지 상승을 지속하나, 그 아래쪽 기온은 상승폭이 둔화되며 수면 부근에서는 외기온 상승폭의 10%에 그쳐 오후 내내 거의 일정한 온도를 유지한다. 외기온의 하강이 시작되면 위치와 무관하게 같은 비율로 냉각되나, 일몰 후에는 초관 하부의 냉각이 지연되면서 자정 무렵에는 상하 중립인 구조를 갖는다.

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수도(水稻)에 대(對)한 가리추비(加里追肥)의 효과(效果)와 NK-복비(複肥)의 비효(肥效) (Effect of Potash top dressing and NK compound Fertilizer on Paddy)

  • 오왕근;김우진
    • 한국토양비료학회지
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    • 제10권2호
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    • pp.79-84
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    • 1977
  • 수도(水稻)에 대(對)한 가리추비(加里追肥)의 효과(效果)를 재확인(再確認)하고 추비용(追肥用) NK 복비(複肥)의 필요여부(必要與否)를 검토(檢討)하고자 수도품종(水稻品種) AKIBARE를 가지고 몇가지 시제(試製) NK 복비(複肥)의 비효(肥效)를 단비(單肥)(요소(尿素)와 염화가리(鹽化加里))와 대비(對比)하여 포장시험(圃場試驗)을 하였으며 이 시험(試驗)에서 얻어진 결과(結果)는 다음과 같다. 1. 수도(水稻)에 대(對)한 가리추비(加里追肥)의 효과(效果)는 현저(顯著)하여서 무가리구(無加里區)의 수량(收量)에 대(對)하여 가리(加里)를 전량기비(全量基肥)로 시용(施用)한 구(區)의 수량(收量)은 유의성(有意性)있는 증수(增收)를 못하였으나 염화가리(鹽化加里) 또는 NK 복비(複肥)를 기(基)(2/3)추(追)(1/3)비(肥)에 분시(分施)한 구(區)에서는 유의성(有意性)있는 증수(增收)를 하였다. 2. 소두대(小豆大)로 조립(造粒)한 NK복비(複肥)는 비효(肥效)가 늦어서 수비(穗肥)로 했을때는 증수효과(增收效果)가 적고 유효분벽비(有效分蘗肥)로 했을때는 증수효과(增收效果)가 있었다. 3. 수도(水稻)에 대(對)한 추비용(追肥用) NK 립상복비(粒狀複肥)는 더 세립(細粒)으로하여 용해(溶解)를 촉진(促進)하거나 아니면 수비기(穗肥期)보다 일찍 시용(施用)해야 할 것 같다.

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경량기포 콘크리트 부산물 시용이 잔디의 생육에 미치는 영향 (Effect of Autoclaved Lightweight Concrete on the Growth of Zoysia Japonica Steud)

  • 육창수
    • 한국토양비료학회지
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    • 제31권4호
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    • pp.368-372
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    • 1998
  • 한국산 잔디를 미사질 식양토에 경량기포 콘크리트 부산물(ALC)를 2.0, 4.0, $6.0Mg\;ha^{-1}$의 처리구별로 시용하고 재배하였을 때 잔디의 생육상태, 무기양분의 흡수와 수량 및 시험후의 토양의 화학적 성질변화에 미치는 영향을 포장시험에 의하여 조사한 결과는 다음과 같다. 잔디 이식 180일 후의 지상포복졍의 총길이, 지상포복경수 및 지상포복경수당 길이는 ALC $2.0{\sim}6.0Mg\;ha^{-1}$구에서는 증가하였고 $8.0Mg\;ha^{-1}$구에서는 감소하였다. 잔디 수확후의 생체중과 건물중은 ALC $6.0Mg\;ha^{-1}$구에서 가장 많았고 $8.0Mg\;ha^{-1}$구에서는 오히려 감소하였으며 ALC 처리구간에 유의성이 인정되었다. 수확기에 잔디의 무기성분 중 Si와 Ca는 ALC 처리량이 많을수록 높았고 기타성분은 차이가 크지 않았다. 시험후의 토양의 pH는 특히 ALC 시용량이 많을수록 pH는 5.7~6.4까지 상승하였으며 Si는 $19{\sim}28Mg\;ha^{-1}$ 수준으로 높았다.

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얌빈 생육과 괴경 수량에 영향을 미치는 재배요인 (Cultural Practices Affecting the Growth and Tuber Yield of Yam Bean (Pachyrhizus erosus L.))

  • 남효훈;권중배;이중환;손창기;서영진
    • 한국자원식물학회지
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    • 제32권1호
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    • pp.38-44
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    • 2019
  • 새롭게 도입된 얌빈의 국내 재배기술 확립을 위하여 육묘조건, 적심, 적화, 재식밀도 등의 재배요인에 의한 생장과 수량반응을 조사한 결과는 다음과 같다. 얌빈은 P.E. 하우스내에 전열 온상을 설치하여 평균 $22^{\circ}C$로 유지하여 30일(적산온도 $650^{\circ}C$) 육묘하면 건전묘 생산이 가능하였다. 트레이 규격에 따른 출현 특성의 차이는 없으며, 셀 크기가 클수록 묘 생장량이 증가하지만 육묘효율, 이식작업의 편의성을 고려하여 128공 트레이가 적합하였다. 7월 하순에서 8월 상순에 120 cm 높이에서 적심을 하면 수량이 23% 가량 많아지며 8월 하순에서 9월 상순 사이에 적화를 하면 괴경수와 괴경중이 증가하여 수량이 32% 가량 많아진다. $50cm{\times}30cm$로 정식하였을 때 관행 $100cm{\times}30cm$보다 수량이 30% 증가하였다. 적심, 적화, 재식밀도 최적조합처리는 무처리에 비해 경제적으로 107%의 이익적인 요소가 발생하였다. 이상의 연구 결과 얌빈의 최적 재배기술 적용을 통해 국내에서 새로운 소득 작목으로서 유망할 것으로 판단된다.

하우스에서 재배된 새싹인삼의 재배시기별 생육, 유효성분 및 물성의 변화 (Changes in Growth, Active Ingredients, and Rheological Properties of Greenhouse-cultivated Ginseng Sprout during its Growth Period)

  • 성봉재;김선익;지무근;이희철;권아름;김현호;원준연;이가순
    • 한국약용작물학회지
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    • 제27권2호
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    • pp.126-135
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    • 2019
  • Background: The ginseng ginsenosides, which have various physiological activities, are known to be more abundant in the leaves than in the roots, and the consumers' interest in ginseng sprout as a functional vegetable has been increasing. Methods and Results: The aim of this study was to investigate the effects of growth period on growth properties, active ingredients and rheology of ginseng sprouts cultivated in a non-heated greenhouse equipped with a shade net for 60 days, starting from the end of May to the middle of July. The chlorophyll content of the leaves decreased, but their length and width increased with increasing cultivation days. In particular, growth increased significantly until 40 days, but only slightly after 50 days. The stem length did not increase greatly from the 20 th to the 30 th day of cultivation, but increased significantly from the 30 th to the 40 th day, and then further increased gradually. The weight of the leaves, stems, and roots increased slightly, but not change significantly. After 40 days of cultivation, the total ginsenoside content increased by 1.07 times in the leaves and decreased by 0.80 times in the roots with increasing cultivation days. The leaf contents of ginsenosides $Rg_1$, Re, $Rb_1$, Rc, $F_3$ and $F_4$ increased with increasing cultivation days. The rheological properties of ginseng sprout showed the greatest influence on stem hardening with increasing cultivation days. Conclusions: Therefore, based on the growth characteristics, active ingredients and physical properties, 40 days after sowing was considered to be an appropriate harvesting time for ginseng sprouts.

등숙기 온도에 따른 쌀가루 가공용 벼의 등숙특성 변이 구명 (Effects of Temperature on Grain Filling Properties of Rice Flour Varieties during the Ripening Stage)

  • 양서영;황운하;정재혁;이현석;이충근;최명구
    • 한국작물학회지
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    • 제66권1호
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    • pp.1-7
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    • 2021
  • 쌀가루용 품종의 등숙기 온도에 따른 등숙특성 변이를 구명한 내용은 다음과 같다. 1. 고온(28℃)에서는 바로미2의 천립중이 21% 감소하면서 새누리(6% 감소)와 설갱(12% 감소)에 비해 크게 줄어들었으며, 전분함량의 감소 또한 바로미2에서 10% 이상으로 새누리와 설갱의 1~3% 감소와 대비되었다. 2. 저온(18℃)에서는 새누리나 설갱에 비해 바로미2의 등숙 속도가 매우 감소하였으며 특히 등숙 초반에 종실중의 증가가 매우 느렸다. 그러나 최종 천립중 및 전분함량은 22℃보다도 약간 증가하며 다른 품종과도 비슷한 것을 확인하였다. 3. 앞서 언급한 것처럼 쌀가루 가공용 품종 중 분질미(바로미2)는 등숙기 온도에 민감하기 때문에 추후 분질미 재배시 등숙기에 고온을 피할 수 있도록 이앙시기를 늦추는 편이 좋으며, 다만 과도하게 늦출 경우 저온조건에서 등숙기간을 제대로 확보하지 못하여 등숙이 충분히 되지 않을 수 있기 때문에 주의가 필요하다.

수도에 대한 완효성비료 METAP의 비효시험(1972) (Studies on the Controlled Release Fertilizer METAP Application on Paddy Rice (1972))

  • 이은웅;안수봉;이문희;이주열;송남현;권순목;김칠용;최병초;정현식;조병옥;이일주;박창서;고춘산;박건호;정성채;정환수;이희덕;박성태;이한생;최승락
    • 한국작물학회지
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    • 제13권
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    • pp.107-118
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    • 1973
  • 완효성 비료로서 METAP이 수도의 생육 수량 및 그 구성요소에 미치는 영향을 검토하고 그 효과를 단비와 비교하고자 농촌진흥청산하 3개작물시험장과 7개 농촌진흥원에서 동일한 설계하에서 일련의 시험을 실시하였다. METAP의 효과는 토양의 물리, 화학적 성질, 시용시기, 기상조건, 품종 및 재배법에 따라서도 다른 것 같으며 각 시험장에서 얻은 결과를 요약하면 다음과 같다. 1. 사질토에서 METAP의 시용은 수수를 증가시켜 수량이 증가하였으며 분시가 전량기비시용보다 효과가 좋았다. 그러나 해성토, 배수불량한 토양 및 비옥한 토양에서는 단비시용과 차이가 없었다. 2. 등숙에 요하는 온도가 높고, 조식에서 다수성인 품종(통일)을 비식하고 출수전후에 일조가 부족하고 온도가 낮으면 METAP시용이 등숙률 향상이나 1,000 입중을 증가시키지 못한다.

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밭작물소비수량에 관한 기초적 연구 -토마토 및 가을배추- (Basic Studies on the Consumptive Use of Water Required for Dry Field Crops -Tomato and Chinese Cabbage-)

  • 김철기;김진한;최홍규
    • 한국농공학회지
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    • 제30권3호
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    • pp.25-37
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    • 1988
  • The purpose of this study is to fmd out the bask data for irrigation plans of tomato and chinese cabbage during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration, the maximum evapotranspiration, optimum irrigation point, total readily available moisture and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soji texture for split plot, and three levels, irrigation points with PF 1.8, PF 2.2, PF 2.6 for tomato and those with PF 1.9, PF 2.3, PF 2.7, for Chinese cabbage, soil textures of silty clay, sandy loam and sandy soil for both tomato and Chinese cabbage, with two replications. The results obtained are summarized as follows 1. There was the highest significant correlation between the evapotranspiration and the pan evaporation, beyond all other meteoralogical factors considered. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2. 1/10 probability values of maximum total pan evaporation during growing period for tomato and Chinese cabbage were shown as 355.8 mm and 233.0 mm, respectively, and those of maximum ten day pan evaporation for tomato and Chinese cabbage, 68.0 mm and 43.8 mm, respectively. 3. The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage of growing period for tomato, and at any growth stage till the late of Septemberfor Chinese cabbage. 4. The magnitude of evapotranspiration and of its coefficient for tomato and Chinese cabbage was occurred in the order of pF 1.8>pF 2.2>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7 respectively in aspect of irrigation point and of silty clay>sandy loam>sandy soil in aspect of soil texture. 5. 1/10 probability value of evapotranspiration and its coefficient during the growing period of tomato were shown as 327.3 mm and 0.92 respectively, while those of Chinese cabbage, 261.0 mm and 1.12 respectively. 6. The time that maximum evapotranspiration of tomato can be occurred is at the date of fortieth to fiftieth after transplanting and the time for Chinese cabbage is presumed to he in the late of septemben At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for tomato is presumed to be 74.8 mm and 1.10 respectively, while those of Chinese cabbage, 43.8 mm and 1.00. 7. In aspect of only irrigaton point, the weight of raw tomato and Chinese cabbage were mcreased in the order of pF 2.2>pF 1.8>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7, respectively but optimum irrigation point for tomato and Chinese cabbage, is presumed to be pF 2.6 - 2.7 if nonsignificance of the yield between the different irrigation treatments, economy of water, and reduction in labour of irrigaion are synthetically considered. 8. The soil moisture extraction patterns of tomato and Chinese cabbage have shown that maximum extraction rate exists at 7 cm deep layer at the beginning stage of growth m any soil texture and that extraction rates of 21 cm to 35 cm deep layer are increased as getting closer to the late stage of growth. And especially the extraction rates of 21 cm deep layer and 35 cm deep layer have shown tendency to be more increased in silty clay than in any other soils. 9. As optimum irrigation point is presumed to be pF Z6-2.7, total readily available moisture of tomato in silty clay, sandy loam and sandy sofl becomes to be 19.06 mm, 21.37 mm and 20.91 mm respectively while that of Chinese cabbage, 18.51 mm, 20.27 mm, 21.11 mm respectively. 10. On the basis of optimum irrigation point with pF 2.6 - 2.7 the intervals of irrigation date of tomato and Chinese cabbage at the growth stage of maximum consumptive use become to be three days and five days respectively.

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밭작물 소비수량에 관한 기초적 연구(III)-고추 및 가을 무우- (Basic Studies on the Consumptive Use of Water Required for Dry Field Crops (3) -Red Pepper and Radish-)

  • 김철기;김진한;정하우;최홍규;권영현
    • 한국농공학회지
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    • 제32권1호
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    • pp.55-71
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    • 1990
  • The purpose of this study is to find out the basic data for irrigation plans of red pepper and radish during the growing period, such as total amount of evapotranspiration, coefficent of evapotranspiration at each growth stage, the peak stage of evapotranspiration, the maximum ten day evapotranspiration , optimum irrigation point, total readily available moisture and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soil texture for split plot, and three levels ; irrigation point with pH1.7-2.0, pF2.1-2.4 and pF2.5-2.8, at soil texture of sandy soil, sandy loam and silty clay for both red pepper and radish, with two replications. The results obtained are summarized as follows. 1.1/10 exceedance probability values of maximum total pan evaporation during growing period for red peppr and radish were shown as 663.6 mm and 251.8 mm. respectively, and those of maximum ten day pan evaporation for red pepper and radish, 67.1 mm and 46.9 mm, respectively. 2.The time that annual maximum of ten day pan evaporation can he occurred, exists at any stage between the middle of May and the late of August for red pepper, and at any stage between the late of August and the late September for radish. 3.The magnitude of evapotranspiration and its coefficient for red pepper was occurred large in order of pF1.7-2.0 pF2.1-2.4 and pF2.5~2.8 in aspect of irrigation point and the difference in the magnitude of evapotranspiration and of its coefficient between levels of irrigation point was difficult to be found out due to the relative increase in water consumption resulted from large flourishing growth at the irrigation point in lower water content for radish. In aspect of soil texture they were appeared large in order of sandy loam, silty clay and sandy soil for both red pepper and radish. 4.The magnitude of leaf area index was shown large in order of pF2.1-2.4, pF2.5-2.8, and pFl.7-2.0, for red pepper and of pF2.5-2.8, pF2.1-2.4, pFl.7-2.0 for radish in aspect of irrigation point, and large in order of sandy loam, silty clay, sandy soil for both red pepper and radish in aspect of soil texture 5.1/10 exceedance probability value of evapotranspiration and its coefficient during the growing period for red pepper were shown as 683.5 mm and 1.03, respectively, while those of radish, 250.3 mm and 0, 99. respectively. 6.The time that the maximum evapotranspiration of red pepper can be occurred is in the middle of August around the date of ninetieth to hundredth after transplanting, and the time for radish is presumed to be in the late of September, around the date of thirtieth to fourtieth after sowing. At that time, 1/10 exceedance probability value of ten day evapotranspiration and its coefficient for red pepper is assumed to be 81.8 mm and 1.22, respectively, while those of radish, 49, 7 mm and 1, 06, respectively. 7.Optimum irrigation point for red pepper on the basis of the yield of raw matter is assumed to be pFl.7-2.0 for sandy soil, pF2.5-2.8 for sandy loam, and pF2.1-2.4 for silty clay. while that for radish is appeared to be pF2.5-2.8 in any soil texture used. 8.The soil moisture extraction patterns of red pepper and radish have shown that maximum extraction rates exist at 7 cm deep layer at the beginning stage of growth in any soil texture and that extraction rates of 21 cm to 35 cm deep layer are increased as getting closer to the late stage of growth. And especially the extraction rates have shown tendency to be greatest at 21cm deep layer from the most flourishing stage of growth for red pepper and at the last stage of growth for radish. 9.The total readily available moisture on the basic of the optimum irrigation point become 3.77-8.66 mm for sandy soil, 28.39-34.67 mm for sandy loam and 18.40-25.70 mm for silty clay for red pepper of each soil texture used but that of radish that has shown the optimum irrigation point of pF2.5-2.8 in any soil texture used. 12.49-15.27 mm for sandy soil, 23.03-28.13 mm for sandy loam, and 22.56~27.57 mm for silty clay. 10.On the basis of each optimum irrigation point. the intervals of irrigation date at the growth stage of maximum consumptive use of red pepper become l.4 days for sandy soil, 3.8 days for sandy loam and 2.6 days for silty clay, while those of radish, about 7.2 days.

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밭작물소비수량에 관한 기초적 연구(II)-마늘 및 오이- (Basic Studies on the Consumptive Use of Water Required for Dry Field Crops (2) -Garlic and Cucumber-)

  • 김철기;김진한;정하우;최홍규;권영헌
    • 한국농공학회지
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    • 제31권3호
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    • pp.41-56
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    • 1989
  • The purpose of this study is to find out the basic data for irrigation plans of garlic and cucumber during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration and the maximum evapotranspiraton, optimum irrigation point, total readily available moisture, and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soil texture for split plot, and three levels ; irrigation points with pP 1.7-2.1, pP 2.2-2.5, pP 2.6-2.8, for garlic and those with pP 1.9, pF 2.3, pP 2.7, for cucumber, soil textures of silty clay, sandy loam and sandy soil for both garlic and cucumber, with two replications. The results obtained are summarized as follows 1.There was the highest significant correlation between the avapotranspiration of garlic and cucumber and the pan evaporation, beyond all other meteorological factors considered, as mentioned in the previous paper. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2.1/10 probability values of maximum total pan evaporation during growing period for garlic and cucumber were shown as 495.8mm and 406.8mm, respectively, and those of maximum ten day pan evaporation for garlic and cucumber, 63.8mm and 69.7mm, respectively. 3.The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage between the middle of May and the late of June(harvest period) for garlic, and at any stage of growing period for cucumber. 4.The magnitude of evapotranspiration and of its coefficient for garlic and cucumber was occurred in the order of pF 1.7-2.1>pF 2.2-2.5>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF2.7 respectively in aspect of irrigation point and of sandy loam>silty clay>sandy soil in aspect of soil texture for both garlic and cucumber. 5.The magnitude of leaf area index was shown in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 for garlic and of pF 1.9>pF 2.3>pF 2.7 for cucumber in aspect of irrigation point, and of sandy loam>sandy soil>silty clay in aspect of soil texture for both garlic and cucumber. 6.1/10 probability value of evapotranspiration and its coefficient during the growing period for garlic were shown as 391.7mm and 0.79 respectively, while those of cucumber, 423.lmm and 1.04 respectively. 7.The time the maximum evapotranspiration of garlic can be occurred is at the date of thirtieth before harvest period and the time for cucumber is presumed to be at the date of sixtieth to seventieth after transplanting, At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for garlic is presumed to be 65.lmm and 1.02 respectively, while those of cucumber, 94.8mm and 1.36 respectively. 8.In aspect of irrigation point, the weight of raw garlic and cucumber were increased in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF 2.7 respectively. Therefore, optimum irrigation point for garlic and cucumber is presumed to be pF 2.2-2.5 and pF 1.9 respectively, when the significance of yield between the different irrigation treatments is considered. 9.Except the mulching period of garlic that soil moisture extraction patterns were about the same, those of garlic and cucumber have shown that maximum extraction rate exists at 7cm deep layer at the beginning stage after removing mulching for garlic and at the beginning stage of growth for cucumber and that extraction rates of 21cm to 35cm deep layer are increased as getting closer to the late stage of growth. 10.Total readily available moisture of garlic in silty clay, sandy loam, sandy soil become to be 18.71-24.96mm, 19.08-25.43mm, 10.35- 13.80mm respctively on the basis of the optimum irrigation point with pF 2.2-2.5, while that of cucumber, 11.8lmm, 12.03mm, 6.39mm respectively on the basis of the optimum irrigation point with pF 1.9. 11.The intervals of irrigation date of garlic and cucumber at the growth stage of maximum consumptive use become to be about three and a half days and one and a half days respectively, on the basis of each optimum irrgation point.

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